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Bodgy
29th Sep 2005, 11:16 AM
I have two Torquemada front vises, that are far from satisfactory. when one clamps a piece of work that is relatively thin, in the top portion of the timber jaws, the front jaw top tends to flex away and consequently doesn't hold the work firmly and tears the fixing screws out of the timber jaw piece.

My solution is to weld a backing plate onto the front vise jaw that will extend almost level to the top of the bench, which forms the rear jaw.

My question is, can I successfully weld mild steel to the cast steel of the vise? The vise is a mid range model and I would presume the casting is also of a mid range quality. I have an electric stick welder only.

Greolt
29th Sep 2005, 12:20 PM
You can but it is moving into pretty specialised area. I am a boilermaker and I wouldn't bother.

Countersunk head "Unbreakos" (spelling?) would be what I'd be thinking.
Either tapped onto the cast or with nuts if tapping threads is not easy for you.

Greolt

Grahame Collins
29th Sep 2005, 07:33 PM
Your vice does not seem satisfactory to your needs. If so, I see no harm in bracing the the front jaws with a stiffeners to prevent flexing.
Are you sure that you are in fact dealing with cast steel and not cast iron.
cast iron repair is very speciliased.

A quick test is to lightly grind an area where it will do no harm.
Cast iron will throw a red spark with short sprigs, whereas cast steel is more of a yellow orange colour with much longer spark and sprigs. Another sign is the sand cast pattern that goes with cast iron. ;)

I would tend to think that your vice if a cheapy is made of cast iron.
There are cast steel vices around , but not many.
I will keep an eye on this thread and if you reckon it is cast steel can help with a procedure to weld it.
cheers
Grahame

Bodgy
29th Sep 2005, 10:56 PM
Graeme, I'll test the composition of the jaws tomorrow. I was only going on Timbecon's loose description.

On sober reflection I'd probably be better just to put a full length and height steel plate inside the jaw, bolt it securely and countersink the bolt heads into the wood facing plate.

Wood Butcher
30th Sep 2005, 10:52 AM
I was ready Sam Allen's Workbench book recently and he advises that the front jaw of the vice should be tapered to the bottom so that the effect of the jaw flexing away from the work can be counter-acted. Quick (and exagerated) diagram below explains what I mean.

Bodgy
4th Oct 2005, 12:14 PM
According to the spark test the vise is cast iron, so forget the welding. I drilled out the jaw fixing screws and replace with cup head bolts and countersunk the heads. A bit of steel plate to brace the upper, unsupported portion of the jaw, and it's fine. I also sloped the jaw face a bit, as suggested, and it seems to work as per spec. Will do same to big, end vise also.

Doesn't look real pretty anymore, tho. Function over form.

Edd
7th Dec 2005, 07:35 AM
Hello, I'm new to this forum and after reading for ages, I signed up just to offer a possibility here.
I sorta repaired a cast iron vice by mig welding it twice (the first weld cracked off due to lack of sufficient heat. If you want to weld on a vice with cast iron, first heat it to a red (dull or bright) colour with oxy-lpg or oxy-acetylene and then mig weld.

Bodgy
7th Dec 2005, 09:26 AM
Thanks for your input Ed.

The problem with what you suggest is that I (and most others here) only have stick welders. I'd luv oxy and MIG but for a dumb punter's occasional use the bottle hire fees kill it. Additionally it seems gas less MIG wire is soon to be discontinued due to toxic smoke. It never seemed to work too good either.

Hope you have fun here

Andy Mac
7th Dec 2005, 09:40 AM
Hi Bodgy,
Are you quite sure its the jaw flexing and not the guide bars? Just a thought:) !
I fixed a thoroughly buggered vice some time back after a student broke the rear jaw, in a line joining the guide holes....I think they were hammering madly onto it:eek: . I mounted a substantial plate of mild steel behind it, with new guide holes and a clearance hole for the thread, joining the two loose sections by bolting into tapped holes in the casting. Cast iron maybe difficult to weld, but as you probably know is easy to tap. It worked OK, but was replaced the next year.

Good luck!

Bodgy
7th Dec 2005, 10:10 AM
Hey Andy

My quick and dirty fix has improved the situation. You are correct about the guide bars thats part of the problem, however both vises were relatively inexpensive and you generally get what you pay for.

As my current shed is tiny, I never get to use the big end vise. I'm going to re-mount it as another front vise at the opposite (right) end of the bench. This, when used concurrently with other vise and a joining, steel backed length of timber, will probably resolve the issue of horizontal racking.

When I made my mods, I thru drilled the vise face plate. Thought about tapping a thread, but figured thru bolting stronger, easier too and I'm inherently lazy.