Tips & tricks from the Pros
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Ron Covell

Question: I see that the old, traditional English Wheel frames are made from cast iron, but most of the currently produced machines have fabricated frames. Obviously, it is much easier to make a truss-style frame from tubing, but will it be as stiff as a cast machine? And how stiff does an English Wheel frame need to be, anyway?

Answer: I was fortunate enough to be able to buy an old English Wheel with a cast iron frame about 15 years ago. It's a great machine, and it's very stable and stiff. I also have a fabricated machine about the same size, and although it's a bit less rigid, I prefer the modern machine for its ease of use!

My newer machine has a kick wheel for changing the pressure, so I can adjust the pressure 'on the fly' with my foot, keeping both hands on the panel. This is a real advantage. My old cast machine has a hand-wheel to change the pressure, so I have to take one hand off the panel to make an adjustment.

My newer machine has a quick-release, so I can change anvil wheels in about 5 seconds, and the pressure setting remains unchanged. The old machine doesn't have the quick-release, so it takes about 30 seconds to crank down the screw-jack, swap wheels, crank the screw-jack up again, and re-set the pressure.

I have a nice set of 6 anvil wheels for my fabricated machine, and only 3 for the cast one. The 'in between' wheels are VERY convenient!

My old machine weighs around 1000 lbs, and it takes a fork-lift to move it. My newer machine weighs well under 400 lbs, and is on casters, so I can easily move it anywhere in my shop, or outside on nice days. I often take the machine to car shows and workshops, and it's easy to load in my trailer - it simply rolls up the ramp door.

Now, there certainly are cast machines that have kick wheels and quick releases, and often 4 or 5 anvil wheels. I'm just reporting that mine doesn't. In theory it would be possible to mount even a 1000 lb. Machine on casters and roll it around, but not with the ease of my fabricated one.

 
Built by Neal Lea

Now about the stiffness issue. Many people have a misunderstanding of the need for stiffness with an English Wheel frame.
I must say that I have used some home-made machines that weren't stiff enough, but the way they were weak
was that when pushing the metal between the wheels, the top wheel stayed in place and the bottom wheel moved along with the metal as it was wheeled. In other words, the lower wheel would move toward me as I pulled, or away from me as I pushed on the panel being shaped. The problem with this is that it causes the distance between wheel centers to change, effectively changing the pressure between the wheels. The worst machine I ever used had a frame made from an I beam - I beams are very stiff in bending, but rather weak for resisting twisting loads. The backbone of the machine was twisting slightly as I worked, making the pressure setting erratic. It drove me nuts!

Boyd Coddington's shop

With my cast machine, to increase the pressure between the wheels another 50 pounds, I might have to turn the adjuster wheel 1/32 turn. To make the same increase in pressure with the lighter, fabricated machine, I might have to turn the kick wheel 1/8 turn, or four times as much. Nevertheless, once both machines are set to the same pressure, they work very much the same! The only place where you will really notice a difference is if you try to flatten a weld by wheeling. The stiffer machine has an advantage here, but I generally crush my welds flat by planishing with a hammer and dolly, or with a pneumatic hammer, before I get to the Wheel.

Now, let's get down to the nitty gritty. There is a common perception that cast iron is inherently stiffer than steel. Well, friends, believe it or not, pound for pound or size for size, this is simply not true!

Earlier this year, I had some long conversations about many fascinating metalworking subjects with Loren Richards, one of the most savvy and innovative metalworkers I've met. He showed me an old book, published by the Lincoln Electric Company, the same company that still makes welders. The title of this gem is "Procedure Handbook of Arc Welding - Design and Practice". 

They published this book for many years, but the one Loren favored was the 7th edition, published about 1942. This is right around the time when industry was switching from casting heavy parts to fabricating them. A quick read through the book makes it clear why this change took place.

Metal Ace wheeling machine

Steel structures can be made much thinner than parts that are cast. This allows the metal to be place where it is most efficient.

But here's the kicker. A STEEL BEAM THE SAME SIZE AS A CAST IRON BEAM IS 2 to 2 1/2 TIMES STIFFER! That sure got my attention, since I had always thought that cast iron was a great deal stiffer than steel!

Getting back to English Wheels, my company is a dealer for the Right Angle (Metal Ace) line of English Wheels. My own personal machine is made to the specs of the plans that come with the kit. A friend of mine wanted a stiffer machine, so he bought a kit from me, used the basic layout shown in the plans, but doubled the main frame members, making them effectively 4" x 6". By making this one change, he created a fabricated machine that is much stiffer than my cast iron machine! Although he enjoys this additional stiffness, he has told me that many times the stiffness has got him 'into trouble' faster than he would have on a more forgiving machine.

So the way I'd sum all this up is to say that there is nothing like the romance and style of the old, traditional cast iron English Wheels. They really have a wonderful industrial look. But for day-to-day work in the shop, you can make a better machine at a fraction of the cost, by building a frame from steel tubing (or plate), and making it as stiff as you want! Working with plate, you can fabricate a machine with the same elegance as a cast machine, at a much more affordable price.


Questions:
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