September 2011 / Volume 63 / Issue 9|
Getting the best out of bench work
By Tom Lipton
I love working at the bench. Having all my parts and tools at my fingertips along with a steaming cup of coffee is truly pleasurable.
One of my favorite jobs at the workbench is designing or building a tool or small machine on the fly. I use the welding table as my chalkboard to develop ideas. Hand fitting and assembling one of your own designs and seeing it come to life on the bench is extremely satisfying.
All images courtesy of T. Lipton
A large portion of the work a machinist does centers around a workbench of some sort. There is always something to take apart, test fit or clamp down. It’s efficient to have a few tools at your fingertips when doing bench work.
Without a decent vise, a shop is not a shop. And if there’s any item that needs to be high quality, this is it.
I once built a feed auger for a briquette press. The shop had one of those inexpensive offshore vises I call “10 footers.” They look great from 10' away, but when you get close you can see all the Bondo used to fill the casting irregularities. I was using this vise to squeeze the auger flighting down onto its center shaft to place some tack welds. The vise failed as I worked on this screw and made the job that much more difficult.
The boss the handle slides through buried itself in the Bondo-reinforced front surface, reducing the clamping force by half. I responded by cranking the vise even tighter. Something had to give and it was the cheap vise. I was so frustrated I got on the phone and ordered a new Wilton vise for $350 on the spot. I ended up in a little hot water with the boss, but that vise is still in the shop and the cheap one has probably been recycled into garden gnomes by now.
Skip the swivel base in the fabrication shop. You want the vises used in these areas to be rock solid and not move at the wrong time. It’s tempting to get the swivel base, but I guarantee it will let you down at some point when you need the vise to be solid. That’s because you can’t lock it down tight enough with the little handles on the swivel clamps.
For most classes of work, use a maximum vise jaw width of 4". Larger than this and the vise becomes cumbersome to use. Try spinning the handle on a 6" or 8" vise rapidly to open it while you’re trying to position a red-hot part. If the handle doesn’t knock your teeth out, count yourself lucky.
Clamp large-diameter rounds below the vise jaws. Three-point contact makes it more stable.
Install copper jaws in all bench vises. Everybody puts protective covers over the serrated jaws anyway, so why not eliminate the marking problem? Aftermarket covers always fit poorly, which makes it a pain to grip a small, delicate part. Name one thing that would be acceptable with big teeth marks in it. It’s a lot easier to preserve your good work than restore it. Copper jaws are easy to resurface when they get chewed up.
Copper jaws in a vise can act as a heat sink for welding delicate parts. Be sure to use copper instead of brass because brass is hard and slippery whereas copper is soft and springy—just the qualities desired in a vise jaw.
Be sure to mount the vise so that a long part clears the bench below the jaws.
Many people consider vises to be low-tech items, but a cheap one can make your life miserable. Spend the money to get the high-quality vise you deserve. CTEAbout the Author: Tom Lipton is a career metalworker who has worked at various job shops that produce parts for the consumer product development, laboratory equipment, medical services and custom machinery design industries. He has received six U.S. patents and lives in Alamo, Calif. Lipton’s column is adapted from information in his book “Metalworking Sink or Swim: Tips and Tricks for Machinists, Welders, and Fabricators,” published by Industrial Press Inc., New York. The publisher can be reached by calling (888) 528-7852 or visiting www.industrialpress.com. By indicating the code CTE-2011 when ordering, CTE readers will receive a 20 percent discount off the book’s list price of $44.95.
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