magikk Posted May 19, 2018 Share Posted May 19, 2018 Hi everyone,after a few months and a few cans of PB blaster then Kroil penetrating oil i finally got the screws moving in the Fisher double screw vise. Unfortunately the top screw was broken in half.what would be the best way to repair this. From what I've been able to find out on the web my options are brazing it( I've been practicing but not too good yet) or weld with nickel or cast rods but I'm not good with a stick welder.if welding would be better i may have to go to a pro and have them do it.never thought I'd get it loosens up.thanks Mike Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 19, 2018 Share Posted May 19, 2018 Do you really expect useful suggestions without even posting a picture of the break? You'll get all kinds of suggestions from guys who've never held a stinger or torch let alone messed with cast. Are you sure it's cast? Heck I don't even know what you mean by "screw." Pin, block, Male, female? We need to have a better idea of what you want to know to be able to offer meaningful suggestions. Without knowing more all I can suggest is have a pro do it. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Nobody Special Posted May 20, 2018 Share Posted May 20, 2018 With fisher doubles , it's a steel screw, and the thread box is machined into the cast iron. From Josh Kavett (aka Fisher museum guy's) words of wisdom. Either way, if you're not good at brazing or welding, take it to someone who is. Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 20, 2018 Share Posted May 20, 2018 I didn't mean to come across so short, it's a valid question but we still need to know more to offer useful help. I blanked on one of the terms for the female threaded half, Box is right, not block. We still need some pictures. We'll help, honest. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
magikk Posted May 20, 2018 Author Share Posted May 20, 2018 I had thought I read somewhere about them being cast. Glad it’s regular steel should be a easier fix I hope. Thanks mike Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 20, 2018 Share Posted May 20, 2018 Looks like it was pretty crystalized for a while before it broke, the end has been beaten down it shouldn't be shiny. Those screws take a lot of torque, I don't know how much a braze that size will take. I've been out of the welding trade a long time and things change. Were it mine I'd probably try brazing after talking to the guys at the welding supply about the break and the kind of stresses it'll be under. In the mean time I'd be looking for another one, maybe even pricing having one machined. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
magikk Posted May 20, 2018 Author Share Posted May 20, 2018 The shiny parts I wire brushed to clean things up a bit. The break fits pretty close together. I doubt I ever find another one of these vices. At least not one I would pay what I’ve seen them selling for. Getting one machined would another option like you said. Hopefully i can get to a welding shop tomorrow and see what they say. When I got it I wasn’t even sure I’d ever get it loosened up. Thanks Mike Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 20, 2018 Share Posted May 20, 2018 It's a different shine than wire brushing produces. The surface texture shows a section at the lower left in the picture that looks similar to chewing gum and becomes rougher and more gray as you look upwards and towards the right. The initiation point of the break (where it started) is the lower left, probably where the thread stops. As the crack grew, the ends of the screw were hammered against each other maybe by vibrations made in use, say hammering or perhaps just tightening and loosening the jaws. If you have it welded you'll need to have it machined or use a file to clean up the threads. A parts vise or machine shop is probably your most economical bet, time and money that is. You're welcome Mike, my pleasure. Wish I had better ideas. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
magikk Posted May 20, 2018 Author Share Posted May 20, 2018 Ok I see what u mean now looks almost like it’s been peened. And flattened out. Well I kind of felt bad I had thought I broke it getting it apart. I gave it a few whacks with the hammer. If I can get it welded. I don’t mind spending some time with a file or maybe even the dremel tool trying to get the threads cleaned up and usable. The vise is dated 1913 it will be nice to get it back into service. I find gathering up the old tools a nice addition to the hobby. And thanks again. the knowledge base on this board is very much appreciated. Mike Quote Link to comment Share on other sites More sharing options...
beaudry Posted May 20, 2018 Share Posted May 20, 2018 If it was mine , I'd cut the threaded part off of the handle end just where the threads start and the threaded part maybe 1/2'' back to get to clean metal. Bevel and clean and degrease thoroughly and weld it together with mig or stick, setting it up straight in line clamped in a piece of angle iron. Protect the rest of the threads with a piece of sheet metal to make clean up easier The screw will end up a few inches shorter , but you are unlikely to use the vise open more than a few inches 99% of the time anyway. Keep the threads cleaned and oiled Quote Link to comment Share on other sites More sharing options...
jeremy k Posted May 20, 2018 Share Posted May 20, 2018 Clamp it in a piece of heavy angle iron, lining up threads as close as you can - then grind out the accessible area - weld, then turn over and do the same for the other side, this will be the best way to get the threads aligned and stay aligned during welding - you may have to tweek it a touch to straighten after all welding is done, but it shouldn't be much. Then touch up the threads with an angle grinder with a cut off wheel to get into the threads/ or file etc. Quote Link to comment Share on other sites More sharing options...
beaudry Posted May 20, 2018 Share Posted May 20, 2018 I really doubt that the screw is cast iron. I suspect that it is just a low carbon steel and won't require any special heat treat either before or after welding. Unless you get perfect alignment on the threads when welding it in the middle of the threaded section , I suspect that you will have it binding and wearing at that area for the rest the life of the vise. Quote Link to comment Share on other sites More sharing options...
beaudry Posted May 21, 2018 Share Posted May 21, 2018 Just for interest does anyone actually know how that thread was originally formed ? Would it be possible to form it by rolling it hot through some kind of a die ? It doesn't look like it was cut on a lathe with that slightly rounded profile to the threads or maybe that is from wear. Quote Link to comment Share on other sites More sharing options...
Smoggy Posted May 21, 2018 Share Posted May 21, 2018 The thread may well have been turned to that profile given the date of manufacture, rather than just wear. As stated even if perfectly joined the likelyhood of some level of deformity will result in binding, which may or may not be acceptable. You can only try and if it don't work out it's find or make a replacement. Quote Link to comment Share on other sites More sharing options...
magikk Posted May 21, 2018 Author Share Posted May 21, 2018 Hi again guys and thank for all the advice.I just got done welding the screw and after grinding it looks pretty good.I have a bit more work to do with the file and hopefully tonight I'll get a chance to see if it'll screw in. I hope there is some slop in the screw box on these since I'm sure it will be off some.When I thought it was cast it kind of scared me a little. Not to much of a stick welder but OK with a mig. Thanks again Mike Quote Link to comment Share on other sites More sharing options...
Judson Yaggy Posted May 22, 2018 Share Posted May 22, 2018 On 5/21/2018 at 1:40 AM, beaudry said: Just for interest does anyone actually know how that thread was originally formed ? The threads on mine (all 4, I have 2 of them) are clearly turned. There are obvious lathe tooling marks. The interesting thing is that it's not an acme, but rather some sort of buttress thread. Quote Link to comment Share on other sites More sharing options...
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