The Life in Steel

Boring Head - doing it right (for me)

2010-05-16T19:45:00.001-07:00

I decided to stretch my machining skills by making a boring head that would extend to bore up to 3" diameter holes. I found the plans on the web created by Joe Worthy for an engineering program - unfortunately I have lost the link.

As a learning experience it was a success and the good news was that the many mistakes I made -- several of which are part of the final result -- do not interfere with the function.

The first issue encountered was figuring out how the boring head actually works, something obvious to the designer but not to me. Next up were improving my techniques for centering, for measuring, and for milling dovetails and removing broken taps. Then there was deciding when a component had so many mistakes it should be discarded and redone rather then fixed. Painful but not too difficult because it is something done in sculpture all the time.

The most creative challenge, however, was modifying the plans to fit the materials I had available. I well understand that it is not in my character to be a good machinist but I have been trying to do the best I can. It was a kind of breakthrough to successfully figure out how to change a design and make my machining skill limitations work for me rather than try to overcome them. Working with strength rather than overcoming weakness is something I practice as well as teach and, as is so often the case, seeing it in yourself is much harder than seeing it in others.

There is someone who posts on one of the lists I read with the signature, "If you can't do it right then don't do it at all." There is a truth in that however there is also a truth in getting it done even if you can not do it right.

I love it when a plan comes together!

2010-01-15T19:23:00.000-08:00

I wanted to make a set of fire place tools and was inspired by some parts made by King Architectural Metals. They are called baskets and are traditionally made by blacksmiths to demonstrate their skills. These are machine made and I thought they would make nice handles. The photo shows all the ingredients; some sheet metal, a basket, some 1/2" EMT left over from a project, and a steel ball which is also from King.

Although EMT is galvanized and one needs to take care of the fumes when welding the inside dimension is 1/2". This works nicely with the basket which is designed to fit into a 1/2" diameter.

I had the design pretty firmly in mind and so did not make any plans. The next photo shows the results, exactly as I had pictured it. While my welding still needs a lot of improving my grinding has gotten pretty good to compensate.

One thing leads to another - Ring Roller interlude

2009-11-12T20:47:00.000-08:00

Some friends asked me to design a gate that incorporated calligraphy in the design. I thought I would do the calligraphy inside a circle and I started working on a prototype. I usually make circles by wrapping some 1" x 1/8" bar stock around a cylinder of some kinds a piece of pipe ora paint can for small ones or a trash can for big ones. This circle was about 12" in diameter and nothing in the shop was the right diameter. I thought about cutting a piece of MDF in a circle but didn't want to cover all my machines to protect them from the sawdust.

'It's only a prototype' I thought and being lazy, I quickly made the circle using my Diacro #2 bender. This is a beautiful piece of equipment for making precise, discrete bends. I made a small bend every 1" around the circumference and while my friends liked the design, all I could see were the bends, each one a precise angle. I did not want discrete bends, I wanted a smooth circle. In short, I needed a ring roller!

My first stop was the web where I saw lots of expensive ring rollers for sale, and some cheap imports. I went to Harbor Freight prepared to buy one but when I actually saw the way it was made -- not well -- I could not bring myself to purchase it. I wound up designing and building a ring roller with enough capacity to handle up to 1 1/4" wide bar stock, 1/8" thick. Several trials, about five weekends, and I had some education in how to design and fabricate (or rather, how not to d & f). Just as important, I had a new tool and some rings.

I took pics of the design and will post them eventually - too many to put on this blog. As for the gate, I am still working on the overall design.

Three steps backward but four foward!

2009-09-13T20:04:00.000-07:00

Every year I make a ceremonial bowl. As a result when I discovered rotary tables I became enamored. Not only could I make gears but I could finish bowls. Apart from that, they are beautiful machines.

I looked at rotary tables, used a big one on a Bridgeport, and realized the only practical size was an 8" table which can hold a piece that is 5" - 6". They weigh 70 to 80 pounds which is about what I can lift onto the mill. After lusting for about a year I got finally nabbed a nice used table. Perfect - except most of my bowls are larger than 8" and I needed at least a 12" table.

A solution is to extend the size of the table by finding a big disk of plate steel and fastening it to the table. The only problem is that I did not have the steel and, depending on the thickness, it too could weigh another 70 pounds. Because my acquisition of a rotary table was aligned with the Universe (apologies if this is too California) I soon came across a posting by someone who had a similar problem and solved it with an extender. This is four pieces of rectangular steel, each with a protrusion that fits exactly into one of the slots of the table. It has some countersunk holes so it can be fastened to the table, and sticks out a few inches so a large work piece can be held down.

The progression is bowl -> rotary table -> project. The project consisted of four pieces of steel, exactly the same size, with a protrusion that just fits the slots in the table, and countersunk holes right down the middle to hold it down with T nuts. I also drilled an tapped two additional holes so I could screw in pieces from a clamping kit. I can not tell you how many mistakes I made. At least three major mistakes and they were so embarrassing that is all I am going to say about them. Fortunately, I found a way of fixing all of them and making it all work.

The first photo shows the extender in action. There are three extenders (hidden) that are used to hold the various clamps and the mill is cutting a nice arc in 1/4" plate. The work piece itself is about 18" long.

The next photo shows how one of the extension pieces fits in the groove. There are two countersunk holes for bolts that fit the T nuts. The last photo shows this piece turned on its side and one T nut is shown. The extensions convert the 8" table into a 12" table.

Lost Foam Casting 2 - Foam, Surfaces, and Sand

2009-08-13T19:45:00.001-07:00

What foam to use? Almost all foam sold in building supply stores contains fire retardant. The right property for home insulation but the wrong property for casting. The fire retardant makes it hard to cut with a foam cutter and increases the thermal mass which in turn increases the risk of a short pour; i.e. a pour where the aluminum freezes before vaporizing all the foam.

Styrofoam pieces sold at craft stores work fine however the grain is coarse and the price is wrong. The best foam is from packing materials such as boxes that contain appliances, electronics, or computers - fine grained foam, no fire retardant, free.

Surfaces and sand: I like foam casting because it is quick. Make the piece, plonk it in some loose sand, pour. This, however, leaves a rough surface with embedded particles of sand. I like this surface for some of my art but it is terrible for anything that will be machined.

The topic of surfaces depends upon the sand. Using fine sand such as petrobond or green sand will produce a surface that matches the foam surface.

When you use a tool such as a grinder, rasp, or even sandpaper not only does it leave foam dust everywhere but the surface is coarse. A hot wire tool such as a foam cutter or an inexpensive soldering iron seals the surface as it melts foam. Other techniques I have read about, but never tried, are dipping the piece in molten wax and coating with latex paint. Reportedly these leave a smoother surface however as these materials get exposed to molten aluminum they burn.

4 holes, 4 pieces of steel, 4 machinists

2009-08-12T20:45:00.000-07:00

I am making a kind of tool which consists of four bars of steel, each with four holes drilled in it. The holes do not need to be precisely located but they do need to be on center and straight. 4 holes, 4 pieces, no problem.

According to the book, the proper way of drilling a hole is to use a spot drill, then to drill a relatively small diameter pilot hole, and then to drill the full diameter hole. There will be a machine screw put in the hole so I also need to drill a countersink so the top of the screw will be flush with the bar of steel. Let's see -- 4 holes, 4 pieces, 4 drill bits - that comes out to 64 separate operations.

I made a pilot piece and discovered it is a pain to change from spot drill, to pilot drill, to full size drill, to countersink. The other way is to do all the spot drilling, change to the pilot and do all of them, then do all the full size drilling, and then all the countersinks. This too is a pain because it takes awhile to keep lining up each operation on center. And there are 64 operations.

Which is faster - or might there be a different and better way? The books, at least the ones I have, are no help for this basic a question. It takes experience - and so I turned to my favorite machining forum on the web. One reason it is my favorite is that if I am polite even the dumbest question is answered.

I asked, and I got four different and better alternatives to the two methods I had inquired about. With one basic question I received insights that will serve me in my future machining. Throughout my adult life I have learned to value experience and here was yet another proof.

This started me musing on book learning vs. experience, and how this particular body of knowledge is vanishing. Manual machining is almost dead due to computer controlled machining. My lathe is sixty years old and works fine now but in another forty years it will either be scrap or be in a museum. As for today's machinery - which are almost all too big to fit in a home shop - there are already 3D computer printers that print solids. It is fairly easy to see that printing metal, nanotechnology, or something else will whisk away today's computerized machining equipment if not within twenty years, certainly within forty years. Manual machining knowledge is destined to become a tiny niche, much the way there are a very few people who preserve the knowledge of making wooden wagon wheels.

Machining is very interesting to me, and I am so appreciative of experts who share their knowledge, it makes me sad to think of the future. Then I realize this is not knowledge of eternal truth, it is knowledge of the real and material world. Its very nature is to change, perhaps to die, perhaps to morph into something else. The proper response is not sadness but gratitude and enjoyment and even as I type this I am back in that place, in those emotions.

This weekend it's back to the shop. One of those new suggestions would reduce the 64 operations to 20. Hmm....

Lost Foam Casting - 1 Foam Cutter

2009-08-07T20:36:00.000-07:00

All of this treatise on lost foam casting of larger pieces will begin with the same title so, if you are not interested, you can skip these blogs.

The first thing one needs is a foam cutter. A hot wire is superior to cutting, sanding, or grinding foam to a desired shape. It leaves a clean, sealed edge The only downside are foam vapors which can not be good for one's health so I wear a mask when I cut.

There are tons of plans for cutters on the web and the prevailing aesthetic seems to be to make them as much as possible with scrap from your shop. You need a power source, a wire that can get hot, and a way to hold it together.

Power source: A/C is dangerous although some folks use bell transformer. I had a computer power supply that had enough power but shut off as soon as I connected it. My theory is that it was smart enough to sense a short circuit and shut off to not damage the computer. I wound up buying an inexpensive battery charger that puts out 10 amps at 12 Volts. Beware, the more expensive automatic shutoff models do not work because you can not control them. Get the less expensive fixed charge model that produces at least 8-10 amps. I have seen very inexpensive models that put out only 2 or 4 amps and they are not enough.

Wire: Since I weld, I have MIG wire available. Inexpensive, easy to replace, lasts a surprisingly long time. If you do not weld you can get a small spool at Home Depot. I use .023 or .025 wire; .030 works but needs more power to get hot enough so I prefer thinner wire. You do not need expensive wire such as nichrome.

Hear Control: A light dimmer works fine with the battery charger.

Assembly and wiring: As the wire gets hot, it will stretch. In order to keep it tight, the top arm of the cutter is on a pivot (a bolt) and there is a spring at the back to keep it pulling upwards. The bottom picture shows this assembly and a black alligator clips from the battery charger. The red clip is connected to the bottom of the post to a piece of lamp cord that runs underneath the base.

Lamp cord runs from the top out across the arm, and is wrapped around a bolt - you can see it in the top picture. The MIG wire is twisted on to the other side of the bolt. At the bottom there is a hole in the base for the MIG wire to pass through to connect around another bolt to the lamp cord.

To provide clearance for the wiring on the bottom, I glued some wood strips to raise it about an inch.

Bill of Materials: scrap wood; four bolts and nuts; battery charger; light dimmer; outlet box for light dimmer; about 4' of lamp cord; plug; MIG wire.

Design Feature and Flaw. In the middle picture you can see that the top arm is angled. The spring is off to the side so it tilts the arm. As a result the wire is not perpendicular to the base. I will fix this some day but it is only an issue when cutting a very thick piece of foam.

The feature can be barely seen in the bottom photo - a line of holes extending at 1/2" intervals from the wire to the front of the base. These holes are just big enough for a small finish nail. When I want to cut a circle, I run the nail through the center of the foam and put it in the appropriate hole. Turn on the power, rotate the foam, and you have a nice disc of foam.

Casting failure on the way to success

2009-08-02T19:24:00.000-07:00

I did a lot of work in July and took lots of photos with the idea of writing about my adventures with lost foam casting. There is a lot of good material in the backyard metalcasting forum however I seem to have gone beyond what others have posted about -- although I am sure others have succeeded at what I am attempting.

Now that the hook is baited, what am I attempting? To make bigger castings. My goal is to be able to make a piece with as much aluminum as I can handle myself - about ten to twelve pounds.

With small pieces, lost foam is a piece of cake. You make the foam piece, hot glue a sprue and a vent, plonk it in some loose sand, and pour away.

When the piece gets bigger, everything changes. There is too much thermal mass for the molten aluminum to vaporize the foam. Acetone dissolves foam but then the loose sand collapses into the void. The first technique I tried was to put the piece in petrobond sand, ram it up, and then drip the acetone. Acetone and the vapors are very flammable - probably explosive - so I do this the day before pouring so the vapors have a good time to escape. . There is a flask with petrobond in the photo above sitting in the wagon and you can just see the red color of the sand. No explosions so far

When the piece gets bigger than the flasks on hand the options are to build a bigger flask or do something else. My pieces are often odd shapes, my petrobond is limited, my space for flasks is limited, so I opted for the something else - investment casting. This is simply investing, i.e. coating, the piece with a liquid material that becomes solid. Contemporary investment materials are expensive and require firing in a kiln. The process is designed for lost wax rather than lost foam so it will not work. As a result I have been trying a material that worked for sculptors for centuries - sand and plaster. In the photo above I am pouring a small piece in this investment.

So far the investment casts have mostly failed, however I am learning from each failure so it has been a positive experience. More to come.

Full circle

2009-06-10T20:26:00.000-07:00

One of the machinist forums I read had a posting from someone who made a Geneva drive. The disk at the top rotates and the pin, which you can just see at the top left side, catches in the one of the grooves of the elegant piece at the bottom. As it catches the groove it turns the bottom piece, which then pauses until the next groove is caught. There are some animated illustrations of how it works on Wikipedia.

After reading comments of admiration on the machining skills one person asked what use anyone would have for such a thing. I wondered myself and checking Wikipedia discovered the purpose is to change a continuous rotary motion into an intermittent rotary motion. It was first used in clock and watch making where you need to convert a continuously wound spring into intermittent ticks.

Kind of interesting but what caught my attention is that this drive is also used in CNC machines (aka computer driven mills and lathes). Aha! I had a morsel of machining knowledge that my more experienced confreres perhaps did not know. I zipped back to the forum to post and discovered someone already posted they had been using one on a lathe. "I had no idea that's what that was called. Turret on big Warner Swasey VTL uses that for indexing the tools."

Visual inspection.

2009-05-19T20:37:00.000-07:00

My day job has been intense the past few months but a month ago I did get some time in the shop. I did some clean up chores and was finally ready to do some art. Plugged in my trusty foam cutter and it did not heat up. Got out the multimeter and everything seemed fine so I decided my power source, an el cheapo battery charger, had died. I was getting 12 volts, but the multimeter does not measure amps so I concluded something was wrong and I needed a new power source.

Another week and I scored a laptop charger - 15 volts and 4.6 amps or 69 Watts. Close enough to my battery charger which is 12 volts and 6 amps or 72 Watts. Plugged it in and nothing.

Now there is absolutely nothing to foam cutter circuitry. My cutter is a piece of MIG wire, tensioned by a spring, that goes to two terminals. Hook up the battery charger and the wire turns red - what could be simpler? The laptop charger by itself produced 15 volts, but when connected to the cutter produced 0 volts! Then I remembered when I first built the cutter several years ago I tried to use a power supply from a computer. It too did not work and I concluded that the power supply 'saw' the foam cutter as a short circuit and shut itself off. Maybe the laptop charger was smart enough to do the same thing. Another week at work went by.

Back in the shop, I remembered a posting on the Miller welding site. Someone had a problem with their welder, lots of people chimed in with solutions, and it finally turned out there was a loose connection. The guy with the problem had wasted everyone's time trying to analyze the problem and one of the experts in frustration posted, 'Never ask for help until you have performed a visual inspection!'

I carefully examined the foam cutter. Everything was fine. Then I looked at the battery charger and noted that the ground clamp had some corrosion. I was ready to throw the thing out so, what the hell, I cut off the clamp and hooked up the bare wire to the cutter. Mirable Dieu, it worked perfectly.

One step backwards, one step sideways, I was finally ready to make some art. So I did, went to take some pictures, and the camera batteries and the two sets of spares were all dead. Maybe the universe is trying to tell me something.

Bruce, Imogen, and me

2009-02-17T20:25:00.001-08:00

If you do not know him, Bruce Beasley is an internationally exhibited sculptor who lives in Oakland. The picture shows him standing by one of his smaller bronze sculptures. Awhile ago I heard him speak at a retrospective exhibit at the art museum in Oakland.

He wandered through the exhibit which was arranged more or less chronologically talking about what he was thinking when he made various pieces. The amazing thing I discovered was we think alike about the creative process; how a stray thought or image comes to awareness, gets developed, changed, and finally manifested. How the resulting piece of sculpture triggers others that refine, develop, and take the original impulse into new directions.

Now to Imogen Heap, a more or less pop singer and music creator from the UK. I like her voice and, even more, I like the way she creates most of the accompaniment by playing bits and pieces on a piano and using sampling to create a larger sound.

Last week I came across her web site filled with video blogs. In this vblog she rambles on about a song on an album she is creating and talks in almost exactly the same way about creating music as the way I think about sculpture. I know nothing about music but there was instant communication about the creative process. I felt that if I were working in music that I would be working in exactly the same way that she does.

Does this pretty random sample of three make a trend?

Pouring again

2009-02-07T15:21:00.000-08:00

What a relief to get back to casting and art! The first photo shows three castings right out of the furnace. One is a shallow round bowl and the other two are pieces of art. To be more precise, a blob and a piece of art. I also cast a rectangular bowl which is not in this photo. The blob in the middle actually came out the way I designed it but now, I can not imagine why I thought it was any good! The nice thing about aluminum is you can always melt down and recycle your failures.

The next photo shows the rectangular bowl in the mill. I like the contrast of highly machined surfaces with the rough surface that results from sand casting. Those long lines at the bottom of the bowl are caused by the end mill and are variations of, perhaps, several millionths of an inch. You can not feel them - the bottom is perfectly smooth to the touch.

The last photo shows the finished rectangular bowl and the bottom of the round bowl. There is a tremendous joy in using all the machines; saw, lathe, mill, grinder, and wire brush and having them all work in a harmonious way to make the pieces that I envisioned.

Weldors, machinists, and diversity - Part 2

2009-01-30T14:44:00.000-08:00

One problem with horizontal band saws is the vise that holds pieces of metal that are being cut. It does not work well and it only holds pieces of metal that are at least 4 or 5 inches long. What do you do when you want to cut a piece that is only 2 or 3 inches long?

Machinists have three solutions. One is a kind of vise jaw extender. It sits inside the vise, but is longer and extends right out to where the saw cuts. The second is to use milling clamps, which all machinists with a mill have on hand. You have to drill and tap holes in the table of your saw and then you can bolt the clamps down to hold the metal you want to cut in place. The third is a pretty neat idea which involves putting a smaller vise inside the larger vise in such a way that the small vise sticks out to where the saw cuts. The photo shows the small vise holding an odd shaped aluminum casting. The jaw of the saw vise itself is on the Left side of the small vise.

The weldor's solution was to take a piece of angle, drill a couple of holes through the angle into the bandsaw base to make a small shelf that sticks out. Then he just used a Vice-Grip 'C' clamp to hold the small piece of metal. This probably took ten minutes.

The weldor may have thought of this solution because weldors have lots of these clamps in their shop - it is the most used method of holding pieces of metal together to be welded or ground. On the other hand, machinists do not have these kind of clamps in their shop. Even if they did I think they would be uncomfortable with the lack of elegance. These clamps do not hold as well as a machinists vise or milling clamps which are designed to exert thousands of pounds of force. Of course the Vice-Grips hold just fine for the bandsaw but I that might well be irrelevant to a machinist.

I was explaining this to my wise wife who told me there is a lot of research on how people form mental models, and how difficult it is to think 'outside the box.' It is one of the strengths of diversity she said.

Maybe I should join a jewelers forum, and an auto body forum, and a sheet metal forum, and ...

Weldors and machinists - Part 1

2009-01-29T21:11:00.000-08:00

I have mainly learned everything about metal work from trial and error, and the web. I am a member of a welding site, machining site, and horizontal band saw site. When you work in metal you need to cut it. For several years I used a chop saw which uses a big, thin, movable grinding wheel that grinds through the metal. Works just fine but it throws metal sparks, dust, and grit everywhere. Worse, it is not very precise -- especially when cutting angles that have to fit together.

A nicer way to cut metal is with a horizontal band saw which is quiet, much more accurate, and makes very little mess. They come in two flavors; small, really cheap, and poorly made or big and expensive. I did my research by lurking on the horizontal saw site which is devoted to methods to make poorly made saws work well and to improve them.

This is rambling background coming to the point that both welders and machinists use band saws. However their approaches to modifying and improving their band saws could not be more different.

Welders are to the point; make something that works and be done with it. It may be because many of the welding site members are professional weldors, and in many cases, time is money.
Oddly enough, their solutions, usually involve welding!

You might think this unremarkable, however machinists rarely think of welding anything! If they have to put two things together they mill them so they fit within a few thousandths of an inch, drill precise holes and tap them so they can be screwed or bolted together. Machining is a hobby for almost all the site members and many are retired. Designing, machining, and assembling an elegant modification that takes hours or even days strikes them as the natural way to do things.

That is why I was struck by a welder's elegant, simple solution to the problem of holding pieces of metal that are too small for the band saw vise. The machinists have at least three different solutions to this problem but none of them of come close to the weldor's solution. (to be continued)

Tap Troubles

2008-11-03T20:44:00.000-08:00

I am making another chandelier consisting of two pieces of fabricated steel that are joined together by four machine screws into blind holes . Since the screw holes had to line up I clamped the two fabbed pieces together, drilled the four holes through both the first piece of metal into the second piece of metal. Then I tapped the blind holes, drilled a slightly large hole in the first piece of metal, and screwed them together. All the holes were aligned just the way I had in mind.

Then I decided I was unhappy with the way the two pieces of metal were lined up. I've commented in an earlier post that one can get away with a lot in art, but less so with design. These pieces of steel were definitely design. Why did I notice the misalignment now and not before I did the fabrication? The truth is that I did notice but I was so focused on getting the piece done I just ignored the flaw thinking it was not that bad.

A half hour of cutting apart, grinding, and welding and I was again ready to join the two pieces. Two holes lined up, two did not. No problem, the welder was right at hand, so I welded the two holes shut, ground them flat, and remarked the new holes in their slightly different location.

In the back of my mind I remembered reading somewhere that weld material was a lot harder than mild steel. The first clue about this memory came when I drilled the new holes and noticed it took longer. The next clue was when I broke a tap in the first hole. Maybe the tap was worn somehow as it was part of a lot of old taps I had purchased at a closed machine shop? No, the final clue was when I broke a second tap in the second hole.

A definition of insanity I read once was doing the same thing over and over again and expecting a different result. I do this all the time on computers. Type something, it does not work. Maybe I miskeyed it, so I type it again. But I only do it twice. My typing is not that bad, and two taps in a row could not be bad either.

I am learning machining by experience. This was a pretty cheap lesson with a price of two taps and an hour or so of rework. Learning how to do it right the first time is a harder lesson to learn.

Sand casting emotions

2008-10-24T21:55:00.000-07:00

I am trying to sort out my thoughts about this video on Youtube. First there is amazement because he is doing something in 1 minute and 12 seconds that takes me well over an hour. Take a look, he is filling a mold with green sand, preparing a part that will be cast in the foundry. There is an economy of motion that comes from doing the same thing a zillion times. There is a big stack of molds and when he finishes this one, he will do the next, and the next, and the next.

The filled mold he tosses around weighs 50 to 60 pounds yet he is really hustling. Maybe for the camera but more likely because he gets paid by the piece.

If you do not know any better it looks easy. However if the sand is not just right it falls out or compresses too much. If the sprue is not inserted just right then loose sand winds up in the wrong place and ruins the final piece. When he plonks the final mold down at the end the cavity does not collapse because he has done this so many times the acceptable force is embedded in his muscles.

Sixty times faster than I can do it, sixty times. True, he has a machine to compress the sand, and an air blower for the loose sand whereas I do everything manually. True, everything is set up for efficiency; sand in an overhead compartment so he does not have to shovel it into the mold and the riddle and spruing tool are at hand. This is part of the explanation - but still - the years of repetition and experience are the real difference.

I have done that kind of manual labor in my life but it was a long time ago and I was never as skilled at that job as he is at his. I look at him with admiration and envy although I know he would switch jobs with me in an instant. At the end he looks at the camera as if to say, 'You got that bud'? I have to reply, 'No, I don't think I do and I don't think I ever will.'

75% off

2008-10-19T17:38:00.000-07:00

In the never ending project to clean up my shop I completed the cabinets I was building under my workbench. I got a bunch of magnetic catches from eBay. Now what to use for handles? They are pretty expensive and I did not want to take the time to make some.

Thenmy wife and I were in a hardware store and passed a bin filled with cabinet hardware. $2.00 each but 75% off! That is a perfect price for a shop.

Men of Steel

2008-09-16T21:28:00.000-07:00

An interesting video of building the San Francisco - Oakland Bay Bridge. From an era when men were men, steel was riveted, and OSHA had yet to be on the scene. Only a few years later Rosie was doing the riveting (and the welding), building Liberty ships at the Kaiser shipyards.

Diacro tooling

2008-09-14T16:39:00.001-07:00

Several years ago I bought a Diacro #2 Bender. This is a beautifully made machine for bending steel bar and tube. Put the piece of metal between two pins, apply some leverage, and you have a bend. The Cadillac of benders is the Hossfeld and, IMHO, the Rolls Royce is the Diacro. Of course, if I had a Hossfeld I might reverse the analogy. All of the inexpensive benders on eBay are based on the Hossfeld design because it is much easier to copy.

My Diacro came with a roller nose and no tooling. Easy enough to make some pins but the roller nose is for curves, not sharp bends. Not only do I need a standard nose, I need tons of tooling. Want to bend square or round tube? Want to make sharp 90 degree bends? Want to make spirals? All of these require tooling that, similar to mills and lathes, can easily cost more than the machine.

Over the years I have had the bender, my tooling desire has grown. Finally, with my new mill, I can make it myself. The photo shows my first project, a standard nose which is sitting on the bender. Above it, installed on the handle is the roller nose.

Doing the math, I spent a couple of thousand for a mill that I used to make a tool worth a couple of hundred. Only nine more tools to go before I am even!

Rong Fu Report (RF-45) 4 : Chips at last!

2008-09-05T21:17:00.000-07:00

I've been making chips - mild steel and aluminum - and am pretty happy. I can take big cuts in aluminum (1/2 " and 3/4" two flute HSS end mills) and decent cuts in steel (1/2" four flute). The gears make it easy to get the right speed and when I eventually figure out how to set an exact speed using the VFD with the gears it will be even better.

Since my old mill did not have a quill I was stuck with the typically inadequate translated instructions to figure out how to use it. First, the quill lock lever can block turning the quill fine feed wheel. The photo shows the lock lever in a vertical position and you can see if it gets moved any more to the right to the locked position it will run into the fine feed wheel. After a hint from a friend, I discovered the lock lever is on a spring so you can lock it, and then move the lever to another position.

Next I could not engage the fine feed. The coarse quill adjustment is similar to a drill press - three spokes sticking out of a wheel so you can turn it easily. At the center of the wheel is a knob and I turned it all the way out thinking it would disengage the coarse adjustment. After playing around I discovered it had to be turned all the way in, engaging the coarse adjustment with the worm drive of the fine adjustment.

I spent an evening milling a chunk of 3/4" thick steel getting into the rhythm of using the power feed and the quill. What a pleasure!

Rong Fu Report (RF45) - 3: Problems, problems

2008-08-27T18:15:00.000-07:00

My old mill had a MT2 taper and the new one was R8 so I purchased a set of import end mill holders. None of them would go all the way into the quill and they appeared to hang up near the end of the groove. Either the groove was too shallow, or the pin inside the mill was too long. I sought out the help of a friend, MM. He had sent me a R8 spec and while the groove appeared pretty shallow it did, in fact, meet the specification.

We needed to tram the mill anyway so we decided to turn the head 90 degrees and take a look. Three large nuts needed to be loosened to rotate the head there was a small pin that prevented me from putting a wrench on the right hand bolt head and the nuts were tightened so much we had to use a rubber mallet on the wrench. The pin and a small nut is just visible above to the right of the large nut in the photo.

"What is this about?" I asked. MM showed no hesitation and unscrewed the little nut and pulled it out. Was it bravery on his part? Nah, just lots of experience working on mills. "It's a taper pin" he said and he carefully put it aside.

We rotated the head and there were two pins that fit inside the R8 groove to guide it. The one in the front was fine and the one in the back stuck out two hundredths. A little filing and every end mill holder in the set fit.

We rotated the mill back to apparent zero and he showed me how to tram it. It took only two tries and MM advised me, "This will never happen again. It always takes five or six tries to get it right." Before the final tightening he inserted the taper pin which fit perfectly. Apparently the Rong Fu folks tram the mill, drill a hole, and then insert a pin - a nice touch. In order to loosed the nuts holding the head in place we had needed to hit the wrench with a dead blow mallet. I think they were tightened so much at the factory so shipping would not change the tram.

Finally I was ready to make chips, but MM looked at the VFD and the motor wiring diagram and told me I had wired it incorrectly. My sequence was a plug to the disconnect, then to the VFD, which was wired to the mill switch. In other words, I was delivering 3 phase power to the switch, and then through the switch to the motor. The issue is electronic components in the switch that would eventually cause problems for the inverter, the motor, or both. In addition I could not use the inverter to change the motor speed in this configuration. The proper way was to connect the inverter directly to the motor.

The following weekend I rewired the VFD directly to the motor and discovered I could now change the motor speed with the inverter. Unfortunately this meant that the nice big red OFF button no longer worked and I had to use a tiny button on the inverter to turn the mill off. I knew there would be times I wanted a nice, big, hand off switch so I wired a large DPDT switch controlling all the power to the mill, and put it in a convenient spot. Eventually I will figure out how to wire the mill switches so they control the inverter.

Rong Fu Report (RF45) - 2: Setup and Inspection

2008-08-26T12:23:00.000-07:00

I purchased the mill through J&L Industrial and had lots of conversations with them because the trucker lost the shipment and the situation got complicated. Their customer service is first rate and I have nothing but good things to say about them. During one of these conversations one of their supervisors said that they tested and lubricated these mills and when I checked all the grease points had fresh clean grease and the oil appeared very clean.

Visually, there was one cosmetic flaw in the table casting (L side of the table in the photo) and, l0oking at the inside of the column, there was some casting flash that was easily removed. In addition I was disappointed that the table handles were plastic rather than metal but, all things considered, the mill seemed well made and at the high end of import machinery.

The power to my garage is a long heavy duty extension cord connected to a 110V, 20 amp circuit. This mill comes with either a 1.5 HP, 220V single phase motor or a 1 HP, 3 phase motor. Due to my power limitation, I opted for the 3 phase motor because I could fit a 110V VFD inverter to it. I knew that DrivesWarehouse carried a TECO that would fit these specs. I called them first and got a sales person who was not helpful in answering my questions about how to set up the VFD for a mill.

Surfing the web I found a less expensive TECO at Dealers Industrial Equipment Their sales engineer explained that the JNEV-101-H1, was both newer and had more features than the FM50-101-C and, in particular, produced wave forms that were easier on the motor. His expertise sold me so I bought the VFD and mounted it on a board with a main disconnect, a heavy duty power cord, and a 110V receptacle for the mill X drive motor.

With some trepidation, I wired the mill to the VFD and when I fired it up, the VFD came on but the mill just sat there. What had I done wrong? Finally I figured out that the '5' on the VFD display was hertz rather than amps so I cranked it up to 60hz and the mill started running - that is to say it started running backwards. An easy fix - swapped two of the three hot leads - and it ran in the correct direction.

Rong Fu Report (RF45) - 1: Moving and uncrating

2008-08-25T11:55:00.000-07:00

When I was deciding upon a mill I found reports from others very helpful. If you are interested in art and philosophy - stop reading now - this is about moving and set up.

The stand was delivered a week ahead of the mill and assembly was straightforward. The sheet metal seemed a bit flimsy to support the 800# mill however the stand was well designed to handle the weight. The stand is used for several models of mill-drills and came with instructions for an RF30 or 31. The shipping carton itself, however, had instructions for the RF-40/45. The top of the stand is a chip tray with gutters for flood coolant leading to a hole in the back where one can attach a hose. The top of the stand has 8 holes, 4 aligned for the RF30 models and a different set of 4 for the RF 40 models. There are rubber plugs for the holes that do not get used. Assembly was straightforward - no written instructions but the graphics were clear enough.

I paid extra for a lift-gate delivery so the mill was delivered to my yard. It was on a pallet, crated with mdf. The mdf was a bit scuffed, but everything was in order. I used a long 2 x 4 to pry up the crate, put some 2" pipe under it, and pushed it into the garage. A one person operation although it would have been a little easier to have a second person to place the pipe.

The next step was to uncrate the mill. It came assembled except for the table handles. The entire mill was in a big plastic bag. All of the the exposed metal had the usual grease which was covered with plastic sheeting. I removed all of this, wiped the grease off, and cleaned it further with kerosene. Kerosene is OK but not my favorite smell so I wiped everything as dry as possible and then oiled it lightly.

I started debating how to lift it with the shop crane without damaging the mill - or me! Fortunately the instruction manual had an illustration showing it should be lifted with a sling around the head.

I only had one, relatively short sling, so I put it right at the collar and when I lifted it, the mill tilted slightly to the back so I did not have to worry about it slipping out. While I maneuvered the shop crane, my wife graciously pushed and pulled the mill to align it with the bolt holes. Finally all the bolts were in place and secured, and then I remembered the 4 rubber plugs for the holes that were not used. I decided to push them through from the bottom rather than lift and then realign the mill. The way the gutters are designed I think the inside will stay dry however time will tell.

American Iron Guilt

2008-08-01T10:36:00.000-07:00

My Benchmaster mill is just too small for my needs. The main problems are having only 9.5" between the spindle and the table and a 1/2 hp motor. Nonetheless, I am feeling some guilt over selling my venerable Benchmaster mill (true 'American Iron') and buying an import mill. Note that I am already being defensive by using the word 'import' rather than the truth, "Chinese'. The deeper truth is Taiwanese.

Anyone who knows about machinery knows that mainland Chinese mill-drills range from total junk to merely poor quality. It is not that the Chinese can not, or do not make high quality mills. Rather the home-shop mill-drills they export are driven by price, not quality.

The mill I purchased, a Rong Fu, is made in Taiwan and has a reputation for having decent quality, albeit, not as good as American mills. Of course, there are no American mill-drills and the only smaller American mills that exist are, like my Benchmaster, 40 to 60 years old.

Without further ado, here is my rationalization.

The Benchmaster has no quill, 1/2 hp motor, limited speeds via belts, and uses MT-2 tooling. The RF-45 has a quill, 1 hp 3 phase motor, 6 geared speeds plus a VFD, R-8 tooling, twice the Z Axis , has an X Axis power feed, and like the Benchmaster has dovetail ways. It may not have the rigidity of the Benchmaster but it is not 60 years old.

Does this rationalization carry the day? I will not be happy until I am milling away with half the passes and the same precision. Meanwhile, my wife says, 'Aren't you excited about getting a new mill?'

The dispersal god is smiling

2008-07-31T21:08:00.000-07:00

I'd been trying to sell my car for a month on Craigslist. There were tons of cars for sale, people would call, never show up, then no one would call. Discouraging. Then the gods smiled, four people called, one showed up with cash. Done, done, done.

What does this have to do with metalwork? I've been trying to clean up my shop because I want to invite some fellow machinists to visit and one of them has an immaculate shop. I, on the other hand, have leaves on the floor, half finished projects all over, piles of tools, and even more piles of stuff. I know it is like cleaning before your in-laws visit, but I feel I need to do something before I have them over. And, truth to tell, I want to get a bigger mill and do not have the space.

So under the smiling deity in short order I sold an old welder I never used, sold my old foundry furnace, and sold my old mill. I've got all the space and half the money I need for the new mill. Seems like I am on a roll - but we'll see.

Greeks, Romans, and my welding

2008-07-05T10:42:00.000-07:00

I might be making this up but I recall from somewhere that the Greeks sculpted figures so they could be viewed on all sides - even if the figure could not be possibly seen from all sides. For example, the figures on the sides of temples could not be seen from the back but the sculpture was done completely. It had to do with some idea of beauty or perfection.

Not so for the Romans. If a Roman sculpture could not be seen from one angle, they simply stopped carving at the point where it could not be visible. Perhaps practical rather than perfect.

This came to mind when fixing the stand to my 4 x 6 el cheapo horizontal bandsaw from Harbor Freight. There I was sitting on the shop floor trying to weld a brace into a sheet metal corner. My new knee was throbbing, I could not see very well, and I did some of the ugliest welds possible. The welds will hold OK, but they sure are ugly. On the other hand, they were in a position where they will not be visible - unless someone turns the whole saw upside down.

I am a believer in perfection but sometimes you gotta do what you gotta do and move on.

Lovin' Lost Foam

2008-06-15T19:03:00.001-07:00

While the big piece took an hour to ram up in petrobond the little leaf pieces were just plonked down in play sand. For the right type of piece lost foam is a pleasure!

Here is one of them still hot from the mold. It is interesting to note that the foam leaflets were very fine and fragile yet the cast leaflets are much thicker. The play sand I am using is pretty coarse and very loose so my theory is the aluminum just pushed it a bit to the sides.

Learning Lost Foam

2008-06-15T18:17:00.000-07:00

Finally rehabbed enough to trust my new knee to a pour. The technique of lost foam is still a work in progress probably because I keep pushing the boundaries of my technique. As you can see there are holes in the walls - on the inner left side at the top and middle and the other right side. This piece is a 7" cube, hollowed out, and the walls are roughly 3/8" thick. Typically voids occur when the thermal mass of the foam overcomes the aluminum and it freezes before vaporizing the foam.

The pour was made from the top to the four corners so I would expect voids at the bottom. Maybe the voids near the top are due to the colder temperature of aluminum at the end of the pour. Maybe - but why the voids in the middle? Fortunately it works artistically.

Back in the shop ....

2008-04-27T16:05:00.000-07:00

I've progressed to the point where I can sit in the shop but not operate any machinery. What to do? Make some sculptures from styrofoam, natch! When I get a lot better, probably in a few weeks, I'll fire up the furnace and cast them in Aluminum.

Ever since I visited the Grand Canyon a few years ago I have wanted to make a sculpture that would convey the incredible feeling of being present there. I have tried a few pieces that have all failed and this one is the latest. It is the convergence of the Little Colorado with the Colorado at the Eastern end of the canyon. Not to scale, not very accurate, just an impression of my memory.

The styrofoam slices were cut on my homemade foam cutter - a piece of MIG wire, tensioned by a spring, and hooked up to a battery charger that you can see in the background. I cut the slices and used dabs of hot melt glue to hole them together.

While I was putting the rejected parts of the slices aside I noticed they had some pretty nice shapes. A little work with the glue gun and I had three more sculptures. These slices might be too thin to cast properly. However, unlike the first piece, I do not have a lot of time invested in them and I can cast them using a quick method with loose sand rather than petrobond which is more time consuming.

YouTube bored

2008-04-12T11:40:00.000-07:00

My rehab has progressed to the point where there is not enough pain or books to occupy my attention so I turned to YouTube - for machining videos, natch! The different flavors are very interesting. The fall into amateur, educational, and sales.

In the sales category, all the video sales ads for CNC equipment remind me of a stripper bar - at least the ones I've seen in movies and TV since I've never never been in one. (How did I miss out all these years?) Anyway, the characteristics are pounding rock music, spewing fluids, and smoke. Does this really sell stuff, Matsusura?

Tormach has a much more cerebral approach with light electronic music and commentary on the machine operations, speeds, feeds, and tooling that are being used.

I'll keep my eye out for some other good ones.

My new best friend (s)

2008-04-11T18:40:00.000-07:00

While I was in the recovery room immediately after knee surgery my surgeon walked in, said the operation went well, and patted the Continuous Passive Motion machine that had been delivered a few minutes earlier. 'This is your new best friend,' he said.

It seems that bad outcomes from knee joint replacement operations were mainly due to patients not doing the incredibly painful physical therapy. The solution; dope you to the gills, strap your leg into this contraption, and it bends your knee over and over again. There is some kind of mechanism in the plastic base, probably an acme screw, that pulls your foot up gently bending the knee and then pushes it back down. There are fleecy pads that hold everything in place, a nicely finished stainless steel structure for the machine, and controls for bend angle and bend rate.

Marguerite (friend #1), was my recovery room nurse. She got the fleecy pads on but struggled to figure out how to adjust the device correctly. The delivery guy (friend #2) was no help and quickly bailed. Marguerite recruited the occupational therapist (#3) and then the physical therapist (#4). No matter what they did the stainless steel bar at the end dug into my butt, and part of my leg was not supported. The machine was the wrong size they concluded. 'Don't worry' Marguerite said, 'You are moving to a room and I'll have a new one delivered.'

In my room I met my new nurse, Jensine (#5) who, in her way, was just as fabulous as Marguerite. Maybe it was the drugs but I don't think so - they were both fabulous. The new machine was delivered, set up, and I was strapped in again. The fit was much better but the bar at the end still dug into my butt. After a half hour of bending I noticed that my thigh was moving sideways in a weird way. 'It's broken,' Jensine said and sure enough one of the welds had given way. My TIG welding of stainless sure isn't the greatest but I expected a little better from the medical machine manufacturers.

A third machine was delivered, and Jensine recruited the nurse across the way (#6) to help. She took one look and said, 'The pads are on backwards." Sure enough, a little switcheroo, and I was in the bending business with no pains in my butt. Thank you, thank you!!!

Before I left the hospital my surgeon paid a last visit. 'We like patients to use these machines at home for a few weeks but your insurance doesn't cover it. Do you want to rent one on your own or just do the physical therapy exercises?" I demurred on the machine.

Theft - the chandelier saga

2008-03-26T17:56:00.000-07:00

Good artists copy. Great artists steal. This is an unsourced quote of Picasso who might well have stolen it from T.S. Eliot ("Immature poets imitate; mature poets steal"). Why this quote? Maybe I am trying to rationalize my theft because, for some reason, I am a terrible designer. I always start working on a piece thinking if it goes badly I can fix it up later. Artists can usually pull this off, can cover up, or can even ignore flaws. Designers have to get everything right in their execution.

But to the point, my wife and I were in Design Expo, the fancy Home Depot, getting some track lighting for the kitchen. I noticed a very nice looking light (Hunter-Conroy Geometry Light) and thought it would be great for the dining room ceiling. They had a sale so I talked myself into paying $200 for the light which, as seems typical of of Design Expo, was out of stock. Two months later, it finally came in and when I was installing it I noticed that one of the components was off by about 1/4" - it was not square. I tried to convince myself it would not matter - but it did. So I returned it, waited another month, and then they told me it was no longer available. At this point I had to have the light so I started thinking how to make one.

The design was four rectangles of square tube, each containing a rectangular halogen light. I could not locate a square halogen light but I could find round ones. So I changed the design from squares to linked circles. Solving the light problem I now had to figure out how to bend square tube into circles. Not sloppy circles, but nice circles. Moreover they had to be joined together nicely because in design you simply can not fake bad workmanship. This was beyond my skills, I had met my match. But I still had light lust in my heart and satisfying that lust was worth two hundred bucks.

A few weeks later we were in Design Within Reach buying a couple of chairs. I wandered around and saw a very cool chandelier. $2,600 was a little more than the $200 I was willing to spend but the more I looked at it the more I thought I could make something like it. You be the judge -- is my chandelier a copy or a theft? (Note: the pic in this blog entry is the DWR chandelier).

Postscript: after I finished the chandelier I got a new catalog from King Architectural Metals, a great resource for fancy gates and fences. They now carry square tube circles so maybe my first idea is something I can make.

Metal yards part 2 - Drops and Cut Offs

2008-03-25T19:14:00.000-07:00

The first metal yard I patronized was Alco Iron and Metal in San Leandro. I was referred there by my welding instructor, an attractive lady blacksmith, who said she got great prices with a little flirting. The best deals, she told me, were 'cut-offs' or the left over pieces when they cut something for another customer.

When I went down there I knew flirting would not work. I'm not gay and neither are the guys in the yard. But I did remember to ask for cut-offs and was eventually given directions to an area of shorter pieces, all jumbled together, and was gratified to get a discount. Service at Alco turned out to be reserved for big orders and little orders like me got short shrift from the yard guys and the counter guy. And, should you wonder, every person in a metal yard is a guy.

Several months later I discovered Naylor Steel in Hayward. Viva la difference! A much smaller operation than Alco but everything was organized. The yard guys were helpful, efficient, and even loaded up my truck. However when I asked for 'cut-offs' I got a blank look. When I explained, they said, "Oh, you mean 'drops.' " They too were neatly organized in bins according to shape and size. At the front counter is a display showing every steel shape they have in stock, measuring tapes you can borrow, and wipes to clean your hands if you forget to bring gloves.

Naylor is 20 minutes further than Alco, but they got my business.

Carhenge and my dream

2008-03-25T18:09:00.000-07:00

An email from a friend about big cubes somehow reminded me of Carhenge . It was designed by Jim Reinders, student of Stonehenge, and built by his family and friends. It is a memorial, a tourist attraction, and many people think it is a kind of joke - or at least something to smile about or perhaps smile at.

Having wandered about Carhenge several times there is also a quality of mystery about the space just like it's namesake, there is a way the dolmenic shapes organize the space of the plains, and there is the surprise of seeing an Edsel.

Wonderful things can happen when artists intersect with junk. As for my dream, it is to someday be artist in residence in a scrap yard.

Metal yards - starting with junk

2008-03-24T18:55:00.000-07:00

Just as wood comes in shapes so does steel. There are only six; bar, rod (square and round), tube, pipe, plate, and sheet. That's it. When I was a beginning wood sculptor, I would find interesting branches and roots, and then combine them with machine cut wood or plywood to make a sculpture. Eventually my technique improved so I could do whatever I wanted. My method evolved from starting with a branch to visualizing the finished piece and then making it.

When I first started to make welded sculpture I barely could weld two pieces of steel together. I could not 'see' a finished piece in my head and fabricate it. I started visiting junk yards, looking for odd pieces of steel in the same way I looked for branches and roots. To the chagrin of my neighbor, I filled my driveway with junk metal so I would always have an interesting piece to kick start the creative process.

My favorite yard was South Bay Metals in Gilroy. They had acres of treasures so every time I got down to Gilroy I would stop by. A few years ago I would never have revealed this treasure lest other artists get the good stuff. This treasure can be revealed because, alas, they were not making enough money in the scrap business and started cleaning up the yard. The acres of treasures have been reduced to just a few desultory containers. I still stop by but it is not the same.

Fortunately my technique has improved to the point where I no longer need a piece of inspiring junk to get me started. I am not as facile with steel as I was with wood but I am pretty much to the point visualizing the piece and then being able to fabricate it. And I have (mostly) cleaned up my driveway.

Finally a good picture!

2008-03-23T14:05:00.000-07:00

It is amazing how hard it was to take a good picture of this chandelier. The background is distracting, the colors are wrong. the light is too bright, not bright enough. My amateur photographer son got the best one - daylight with a fill in flash. And, yes, I did replace all the plastic candelabra tubes with steel. Turns out that 3/4" EMT is the perfect size.

A new knee

2008-03-15T19:45:00.000-07:00

Many years after a youthful life with several motorcycles, including one broken leg, the knee on that leg needs replacement. At a pre-surgical orientation meeting the nurse passed around a couple of knees. They are heavy suckers - maybe 3# - look like ordinary stainless but turn out to be a Cobalt - Chromium alloy. The outside surface is highly polished so it can slide on the plastic insert but the inside surface looks like unfinished casting, which I assume is deliberate in order to provide a better surface for the cement.

Orthopedic surgeons are the evolution of 'sawbones', sort-of kind-of the way folks who program CNC equipment are the evolution of blacksmiths. I think in a lot of ways blacksmiths understand more about metal than CNC programmers. Now let's see, this means my surgeon ? Well, I hope he turns out to be an artist with CNC.

Google

2008-03-13T20:11:00.000-07:00

Does Google know about 'the life in steel'? Not yet, but the phrase brought up a paper on the philosophy of the body.

The steel nails forged by traditional Japanese blacksmiths contain more impurities than modern nails produced in the smelting furnace. Yet, it has been discovered that nails taken out from structures built six hundred years ago are still without rust and in perfect condition to be reused today. This fact, which goes against the theories of science, may not in itself demonstrate the belief that everything was alive, but it does suggest how the blacksmith’s long-standing conviction of the life in steel could be poured into a single nail to become a powerful and lasting life force.

The Idea of the Body in Japanese Culture and its Dismantlement, Hiroyuki Noguchi

International Journal of Sport and Health Science Vol2, 8-24,2004 p13

Back to the shop - sort of

2008-03-13T19:53:00.000-07:00

Took a close look at the chandelier and noticed that one of the candelabra covers was shorter than the others. Hmm, what's with that? Turns out my wife left the chandelier on all day because she liked it (thank you!) and it melted one of the plastic covers that had slipped a little bit so the end was touching the bulb. At least it did not start a fire!

This is what I get for using plastic (with chrome spray paint) like the lamp parts guy told me to do. My apparent choices were cardboard and plastic but, as the name of my blog says, I'm going to find some steel.

Half done

2008-03-12T20:13:00.000-07:00

Here is a pic with about half the crystals hung, the rest are still on order. Hard to see it well but you get the idea.

Finished the grooving and more!

2008-03-10T21:15:00.000-07:00

This weekend I finished the grooves, Had some chattering until I centered the cutter very precisely and then it cut beautifully. Welded some ends on the tube - my first stainless steel welding with mig. It too worked beautifully although the welding seemed pretty hot. Might be due to using regular mig Argon mix (75% AR, 25% CO2) rather than the tri-mix you are supposed to use with stainless. I was too cheap to buy a whole tank for two minutes of welding.

The piece is going to be a chandelier and in a few weeks when I get all the crystals hung on it I'll post a pic.

Tool making and empowerment

2008-02-26T17:41:00.000-08:00

When I first learned to weld about six or seven years ago I started noticing welded joints everywhere. Fences, railings, and metal wine racks that had always been in my visual background suddenly popped out and became fascinating. I'd look at an ordinary railing and think, ‘I could make that’.

More accurately I might be able to make that with a few years of training and lots of equipment. When I really thought about it the fascination was that I now knew how it was made. I'd always done home repair kind of stuff but this was much vaster. If push came to shove, I could develop the skills to make a lot of stuff myself.

A few years later when I was struggling with making curved metal shapes I discovered the English Wheel. I had never seen or used an English Wheel but it looked like the right tool. Unfortunately they were really expensive so I started looking on eBay – and they were still expensive. However, some guy was selling the anvil wheels and I had the realization that, even with my modest welding skills, I could buy some anvils and make a wheel. I studied all the pictures I could find, made a design, bought some steel, and built my wheel.

It is hard to describe the profound feeling of empowerment in making a tool. Throughout my adult life I had been making computers dance but this was very different. Computer programming is abstract but tools change the physical world. Somehow I got in touch with one of the creative forces that contributed to the development of civilization. On top of that I could also make nice curved shapes in sheet metal!

Groove tool

2008-02-24T11:34:00.001-08:00

A few minutes with the grinder and I have the tool I need. My first custom tool bit! The holder is a Phase II.

Works fine with mild steel - stainless is next.

Quick

2008-02-22T11:58:00.001-08:00

Fast Service
from Enco. Turns out their warehouse is in Nevada so I got next day delivery with standard UPS. About $4 for a nice piece of HSS 5% cobalt tool steel and $46 for other stuff so I could get the free shipping with a $50 order promo. I really DO need all that other stuff. Off to grind my first home-ground tool bit.

2008-02-21T19:00:00.000-08:00

Groovy

I want to cut a bunch of thin grooves, about 1/2" apart, on a 30" length of 1" tube. Why would I want to do such a thing? That is a mystery that hopefully will be revealed in the future. I don't like to tell too much about a piece until it is done. However, at this moment, how hard could it be? Grab a length of tube, put it on the lathe, and cut some grooves, right?

The first problem is that my lathe (10" swing, vintage 1951) can almost, but not quite, take a 30" length of tube. OK, I'll change my design to 26". Still too long to fit in the chuck with a bull nose live center on the chuck. Hmm, maybe the new (to me) steady rest will be steady enough. Yes, I can see the smiles from all of you who know it is NOT steady enough. Wobbling away, way, way.

I then spent about 1/2 hour messing around with adjustments and a dial indicator to get it really centered in the rest. Still wobbles a bit even to my untrained eye.

All righty-rooty, change the design to 3/4" tube which will fit through my headstock. That should do it - and it does. Got the tube mounted on the lathe. This is a test piece so I just put on the first lathe tool that was at hand with an angled point.

Gee, is round tubing really round? Sort of, but not round enough to prevent the groove from being thin in some places and fat in others where the tube is slightly oval. If you look real close you can see I broke the very end of the carbide tip due to the initial interrupted cuts. By the way this test tubing was painted and the irregularity in the middle of the grooves in the picture is where the paint chipped.

Good thing I don't care how deep the groove is -- but it does have to look even. One contributor to the problem is the screw cutting tool. The triangular shaped cutting part cuts a fatter groove the deeper it goes. I need a rectangular shaped cutting tool rather than a triangle. The parting tool fits the bill but it is 1/8" wide and I want a groove that is around 1/32" wide.

Off to the industrial supply catalogs. Let's see .... groove tools, indexable groove tools, parting tools ..... Closest thing is a groove tool for cutting thin 'O' rings. Just the ticket, except for the tariff which is $43.12 plus shipping. Maybe if I wanted to do hundreds but I only want to do 40 or so grooves for a one-off. Order some rectangular HSS tool stock that will fit in my parting tool holder. Gotta make my own groove tool -- just like a real machinist. (to be continued).