Woden Vice jaws

[Rorschach]

I have a very old Woden 190/7 vice, judging by the colour scheme I would say it came from a navy shop/ship. Despite it's rough condition and slightly bent tommy bar, mechanically it is quite sound, the screw runs smooth, the quick release works perfectly and it hold REALLY tight. The jaws though have seen better days, the grips are very worn and the edges are chipped, the screws are also pretty kackered and come loose from time to time and are rounded. Does anyone know if I can still buy replacement jaws for this model? Or probably more likely does anyone have some stashed away? I'd like to avoid having to make my own if possible.

 

[Mr_P]

First bit of silverline that I actually like.

http://www.ebay.co.uk/itm/Brand-New-Eng ... xym2BSHKi0

Have a set in my ward and payne metal wokers vice.

 

[Bod]

Seeing these vices didn't much change over the years and makes, it might be worth a call to these folk.
http://www.knighton-tools.co.uk/acatalo ... pares.html

Bod

 

[Rorschach]

First bit of silverline that I actually like.

http://www.ebay.co.uk/itm/Brand-New-Eng ... xym2BSHKi0

Have a set in my ward and payne metal wokers vice.

Not quite what I was after, I want to totally replace the fixed jaws in my vice.

 

[Rorschach]

Obviously no off the shelf options, anyone know if you can buy rough jaws you can drill your own holes in etc?

 

[bugbear]

Obviously no off the shelf options, anyone know if you can buy rough jaws you can drill your own holes in etc?

Many jaws are hardened,so drilling would be tricky.

However, (and conversely) engineers doing fine grade work replace their vices hardened (and teethed...) jaws with plain jaws of unhardened mild steel, to protect the work piece.

http://www.model-engineer.co.uk/forums/ ... ?th=107764

BugBear

 

[Rorschach]

I think I will likely end up having to make my own and I will probably go for mild steel, some good points in that link.

 

[Rorschach]

After some research I am definitely going to go for mild steel. While ground gauge plate would be nice it is also at least 3x the cost and for vice jaws which are only going to be beat on anyway it just seems silly, I could get several sets of mild steel and aly jaws for the cost of one set made from gauge plate.

 

[bugbear]

After some research I am definitely going to go for mild steel. While ground gauge plate would be nice it is also at least 3x the cost and for vice jaws which are only going to be beat on anyway it just seems silly, I could get several sets of mild steel and aly jaws for the cost of one set made from gauge plate.

Mild steel is easier to cut and drill too.

BugBear

 

[Rorschach]

Well I made my vice jaws up from the mild steel I ordered. The steel was nicely formed with crisp edges and it was a heck of a lot tougher than I imagined, obviously a fairly good grade. Drilling went fine, tapping was tough but I didn't break the tap, I only used about 80% thread depth, I probably could have gone less to be fair and made it easier on myself. Jaws overhang by 5mm on one side and 20mm on the otherside as per the tip I got here, Looks like they will be very useful and if I don't like the overhang it will only take a minute to chop it flush.

Thanks for the suggestions, look forward to putting them to use.

 

[bugbear]

...I didn't break the tap, I only used about 80% thread depth

Wow. Most people do 75% at most.

Machinery's Handbook (27th ed.), under the heading "Diameter of Tap Drill", says:
Tests have shown that any increase in the percentage of full thread over 60 per cent does not significantly increase the strength of the thread. Often, a 55 to 60 per cent thread is satisfactory, although 75 per cent threads are commonly used to provide an extra margin of safety.

BugBear

 

[Rorschach]

...I didn't break the tap, I only used about 80% thread depth

Wow. Most people do 75% at most.

Machinery's Handbook (27th ed.), under the heading "Diameter of Tap Drill", says:
Tests have shown that any increase in the percentage of full thread over 60 per cent does not significantly increase the strength of the thread. Often, a 55 to 60 per cent thread is satisfactory, although 75 per cent threads are commonly used to provide an extra margin of safety.

BugBear

Well it was the closest I could get. 7mm drill is what I usually use for an M8, 7.5mm is the next size drill bit I have and that would make the thread far too weak in my opinion, taking into account inaccuracy in drill size etc I think 7mm gives a pretty good thread depth for M8 and is what most people would recommend I think.

 

[MattRoberts]

Any pics?

 

[bugbear]

...I didn't break the tap, I only used about 80% thread depth

Wow. Most people do 75% at most.

Machinery's Handbook (27th ed.), under the heading "Diameter of Tap Drill", says:
Tests have shown that any increase in the percentage of full thread over 60 per cent does not significantly increase the strength of the thread. Often, a 55 to 60 per cent thread is satisfactory, although 75 per cent threads are commonly used to provide an extra margin of safety.

BugBear

Well it was the closest I could get. 7mm drill is what I usually use for an M8, 7.5mm is the next size drill bit I have and that would make the thread far too weak in my opinion, taking into account inaccuracy in drill size etc I think 7mm gives a pretty good thread depth for M8 and is what most people would recommend I think.

Good point - the difference between (marked) drill size and final hole size can be significant.

BugBear

 

[Rorschach]

Good point - the difference between (marked) drill size and final hole size can be significant.

BugBear

Yes it can, especially when using a hand drill but even when using a drill press. Only mt lathe (metal) drills as close to spot on as you can expect.
For tapping I usually look at the tap drill size, so 6.8 for an M8 and then go up to the closest drill size, 7mm unless it's thin sheet like aluminium in which case I drill to actual size or possible even one under, so 6.5mm for M8 and this seems to work well for me. If the hole is too tight for the tap I can always step up a drill size to ream it out a bit, much harder to make the hole smaller if the thread is too shallow.
I find M6 to be a pipper though, on anything but sheet or soft metals it is hard to get a good size drill, 5mm is ok for the former but for steel you will break the tap with ease (done it many times), but 5.5mm leaves a very weak thread.

 

[Rorschach]

Sorry I totally forgot about pics, added now, one with a rule for scale to show the overhang on each side. Not sure how this overhand will play out, not really needed it yet so time will tell, if I don't like it though it is only a few minutes with a thin cut off disc in the angle grinder to trim them down to size.

 

[DTR]

A bit late now, but I did the same thing with aluminium jaws:

The wider jaws are definitely a plus.

 

[Rorschach]

Well I used the overhang yesterday when fitting eyelets to some shoes. The overhand let me clamp the setting tool in a position where I could manoeuvre the shoe around it, wouldn't have got into all the places otherwise. Despite it having smooth faces, gripping a round tool and overhanging past the main body it didn't slip at all during hammering 2 dozen eyelets. So very pleased with that result. I do think I need to get myself some kind of jack or adjustable piece to grip in the opposite side of the jaws though to stop it racking too much, it was fine this time but if I needed to crank the handle down more it might have caused some trouble.