An Adventure in Leg Vise Rebuilding

Article written and contributed by Tim Suter

I happened upon a very old leg vise at a garage sale, that attracted my curiosity. Naturally it was ridiculously high priced, which I questioned and received the standard qualification that "it is old". ( So am I but Iím not worth more.) Tactfully I explained that I doubted that it would bring that price as I had seen others in much better condition at venues where there were interested buyers who would never pay that much. Looking it over, it had no spring, the handle was a piece of 3/4 bar, bent over at each end and the screw moved erratically. Leaving. I decided that I would like to have it for the challenge, if the price was right. I kept my eyes on it for the next three weeks and it hadnít moved. I felt the time was ripe so, approaching the seller with tempting green in hand, I boldly asked him if he was ready to part with it for a realistic price. He asked what that would be, I said $25, he said $30. Quick as a hootie owl snatching up a June bug I slapped the green in his hand and the good, stout, young fellow even lifted it into the pick-em-up truck for the congenial old gentleman.

Getting it home I promptly tore it down for clean up and closer inspection. This was indeed an old and very interesting vise. It appears to have been made by hand, hammer and anvil, without the use of a mechanical hammer. The screw box eyes were formed by the leg stock (1 1/2" X 1 1/2") being forged out to 5/8 X 3 X 16 inches, folded over at about eight inches, the eye formed around a mandrill and forge welded back into itself, then forged to octagon to round and with the usual upset at the bottom. The jaws themselves are a separate forging, forge welded onto the top of the legs. At the bottom of the movable leg is an offset for the pivot bolt hole. It appears to have been made with two pieces of the 1 1/2" square stock 3 1/2 inches long stacked at the inside bottom of the leg and forge welded together. A possible explanation for the 1 1/2" square stock is that it was a common bar stock size

produced by wrought iron finery forges before various standard rolled bar stock shapes became readily available late in the nineteenth century. It was not uncommon for iron bars such as this to be transported to market from remote Pennsylvania mountain forges by being bent to conform and carried over the backs of pack horses. The pivot bolt is 7/8 but tapered for a solid fit into the hinge side plate, the nut was blacksmith made.

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The screw box itself was made up of nine parts. The barrel was a rolled tube 1 1/2" ID X 2" OD with a lap seam, the bell at the back was made the same with a 2" ID. These two pieces were then forge welded together at the end and forged over into a recess in the end plug. The plug itself appeared to have been made with a roll up of thin plate and simultaneously welded as it was forged to shape. The three thrust rings were forged of 5/8" square bar with a lap joint. This joint was not welded. I think the purpose was to have a tight fit but one that could be forced onto the barrel. This was all brazed together as a unit along with the female screw thread inside, and no turn lugs.

I put the screw box assembly in my gas forge and brought it up to bright orange to melt the brass, expecting to easily extract the worn and damaged screw thread. Not so, the thread was distorted and tangled and refused to come out easily, so I bumped it on the pavement several times which promptly distorted the tube to a point of no return. Now I had to take it apart to salvage the thrust rings, end plug and no turn lugs. This was more difficult than you might think. It seems to me that things that have been together a long time like it that way.

To make the screw helix, I formed that with 3/16" key stock, the dimensions came out compatible with the screw thread depth and 1 1/2" ID pipe for the barrel. I wrapped the key stock into the screw threads, carefully correcting a twist that wanted to develop as I progressed. This was done cold so the helix could spring open a bit to have a more comfortable clearance with the screw. Six foot of key stock yielded about eight inches of helix. Next I made a sleeve of .040" brass that fit snugly around the screw helix. (When soldering or brazing reember mothers admonition "cleanliness is next to Godliness") I thoroughly cleaned the inside of the pipe and the brass sleeve, fluxed them with a paste flux and put the thread helix into the sleeve.

I wanted to put the screw into the helix in order to assure a proper thread alignment. The problem would be, how to keep the brass from fluxing onto the screw. This was solved by coating the screw liberally with high temp 1500į spray paint. I cured the paint according to the instructions and ran the screw into the helix. Then the brass sleeve, helix and screw were coaxed into the pipe as a unit, it was a very snug fit. The four foot length of pipe was not cut as I wanted a good handle on a piece that would, otherwise, be awkward to handle with tongs. The eight inch depth of my forge was just right for the heat zone I needed, with the screw excess through the back door. The piece was put in the forge, the forge lit and brought up to heat along with the piece. As it came up to heat I could observe,

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at the end, the flux get fluid then the brass, next the helix come to color and finally the brass flow to the helix. This happened at a bright orange approaching yellow. I rotated the piece slowly arid soaked it at this temperature for several minutes before turning off the forge. (I wouldnít hesitate to try this in a coal forge at another time.) When it returned to a black heat, I took it from the forge and put it in my vise.

Now for the moment of truth, would the screw be free? I tried to turn it with a bar, no movement, donít panic! I bumped the bar with a hammer, again, again, a barely perceptible movement, again, more movement, a sigh of relief. Continued teasing and the screw was out. After fully cooling the screw was teased in and out several times and as the flux residue was broken up the action became increasingly smoother. The pipe was cut to length and the end forged over and into the groove of the end plug, using a torch and localized heat. A short piece of 2" ID tail pipe was forced over the 1 1/2" pipe to form the bell, forged over and gas welded to the 1 1/2' then planished to a nice transition into the contour of the end plug. The thrust rings and no turn lugs were brazed individually to the assembly with the screw back in place to assure preserving thread alignment.

I used a 3/4 X eighteen inch piece of 5160 for the new screw handle. A band of 1/4" X 1/2" was arc welded with a generous fillet at both sides then forged into a suitable ball at each end. The purest could do this in his forge by making a half round with 1/4" X 1" in a swage for the bands. Some jaw mis-alignment was corrected with heat and hammer work at the hinge lugs. The jaw spring of course was no challenge to make.

I had an educational experience, I have a good post vise from virtual junk
and best of all I had fun. Tim Suter.