How to deal with a lop-sided load on a vise
|andrew lyner||08/10/2021 15:13:06|
|240 forum posts|
This must be a common problem. You have a small object that is held out to the side of a vise. You do the vise up tight but it always worries me that there's a tremendous asymmetry / twist to the load on the guides and vise frame. I often rummage around for a similar sized piece to put on the other end of the jaws and, when both pieces are held firm, I reckon I'm saving the vice from needless damage. (Ditto my Workmate.)
It would be ideal if I had a small screw jack to balance up the load. I have tried a pair of thin, reverse-tapers and that works. But is there a specific name for such a device? I'd like to have a look at some alternative approaches - or even buy something.
Every one of you who read this will have had this problem to solve. Problem is that it crops up half way through a job and never really gets my full attention.
|John Haine||08/10/2021 15:34:55|
|4279 forum posts|
Good point! I would guess that the metal body is made of iron or steel selected for strength rather than hardness, so maybe possible to provide a threaded hole at the left side (if you're right-handed) for a jack screw, with a clearance hole in the jaw piece if needed.
|Dave S||08/10/2021 15:38:25|
|266 forum posts|
Never worried about it with my metalworking vices.
A none issue in a workmate - there are 2 screws just balance the loading.
|Andrew Johnston||08/10/2021 15:46:25|
6323 forum posts
My machine vice is somewhat larger, and sturdier, than many of my workpieces, so I don't worry too much, although the manual does warn about asymmetric loading. I don't let the workshop gorilla loose under these conditions. As I am building two nominally identical engines i often have a second part to balance the load anyway.
|andrew lyner||08/10/2021 15:56:47|
|240 forum posts|
Ah yes - "jack screw" finds the sort of thing I am needing on Google. But what I am finding tend to be on the big side. It would be nice to use it for pieces of one or two cm size that could be subjected to some serious forces (not just hacksawing) And on my mini mill, vibration is always with me and some good balancing in the milling vise could help with that.
"A none issue in a workmate - there are 2 screws just balance the loading." oh yes of course - silly me - we do that all the time with a workmate. I need 'that other screw' for other equipment too.
My main problem is on my metal bandsaw which is held by a clamp with a single bolt. Short pieces cannot give a balanced load and something of identical size needs to be put at the other end. That saw is magic and it leaves a smashing finish with a good square cut. If I could use it conveniently and more often, I would be very happy.
|not done it yet||08/10/2021 15:59:59|
|6444 forum posts|
Simply have a range of bolts in different diameters. Drop in the appropriate one at the other end of the vise jaws. Problem solved?
|pgk pgk||08/10/2021 16:16:45|
|2366 forum posts|
On my machine vice I use adjustable parallels. If doing a lot of bench vice work then why not knock up some crude DIY versions?
21649 forum posts
Can't you simply tap a few different lengths of bar after facing off each end and then take another piece of the same bar, turn down and thread one end and face the other.
You then have a simple screw jack made to the size you want that can be adjusted to fill the gap between the jaws. You can also use the same thing to support the end of long overhangs etc.
Personally I don't bother and happily hold small parts at one side of the mill vice if the machining requires access to an end. My woodwork vice doe snot grip so well on the end and I simply have pieces of the common thickness boards I tend to grip with a peg through them and just drop that into the far end of the vice when needed.
Also have a look for Machinist's jack
Edited By JasonB on 08/10/2021 16:42:16
|Mick Berrisford||08/10/2021 16:41:13|
|135 forum posts|
The bandsaw problem is easily solved, think it was Neil who I first saw mentioning it a few years ago. Drill and tap the far end of the moving jaw in the middle M10 or similar. Fit a bolt and you can screw it in and out to match the thickness of the material at the front to stop the jaw skewing too much.
4827 forum posts
Nice idea, cheers
|andrew lyner||08/10/2021 17:52:10|
|240 forum posts|
Good idea Mick. Thanks for the loan of your brain!!!!
|Robert Butler||08/10/2021 18:09:39|
|303 forum posts|
If it bothers you, use thev jacking pieces from a clamping set with scrap strips to balance the work. perhaps ungainly!
|Rod Renshaw||08/10/2021 18:22:07|
|347 forum posts|
I rescued some credit card sized information "cards," made of a hard plastic just like credit cards , when the issue we had in our office was replaced by a new version and we were told to bin the old ones.
I took home a pile about 2 inches high. I drilled a hole through the stack in one corner and fitted a 2 BA nut, bolt and washer to hold them all together - with a bit of slack. I use the appropriate thickness of cards to make up a "pack" of the same thickness as the workpiece, swivelling the unneeded cards out of the way. And I use the pack on the other side of the vice as described in several posts above. I hope that's clear, the cards needed to make up the required thickness go between the vice jaws and the remainder sit just above or to the side of the jaws. All the cards stay on the bolt at all times so none get lost. It works quite well, cost almost nothing, and seems quicker to adjust than a screw jack..
Don't have to be plastic cards, could be small pieces of sheet metal all cut to the same size or even washers with an extra, off centre hole drilled in them.. Good use for off cuts?
|Mike Poole||08/10/2021 18:41:42|
3099 forum posts
I would be careful to be sure the packer or jack does not rob the grip from the job item, the better the vice the more important it will be to match the packer to the job.
|Mike E.||08/10/2021 21:09:08|
216 forum posts
Consider using a cheap leaf gage. You can adjust the number of leaves easily to suit your issue for small parts on the opposite end of your vice jaws.
|bernard towers||08/10/2021 21:15:33|
|343 forum posts|
8 or 10 mm washers slid on to a piece of 3 mm bar which rests on the vice jaws?
|Paul Lousick||08/10/2021 22:59:41|
|1868 forum posts|
I don't have a problem loading up one side of a decent bench vise. A bit different with the cheap pressed metal one on my band saw.
6085 forum posts
Anyone who didn't know the screw modification for the vice on a bandsaw should have a look at the many blogs and youtubes on bandsaw mods as you have probably missed a lot of other tweaks that are helpful.
|540 forum posts|
Another vote for adjustable parallels. If you don't want to buy a set, buy a small one (if you can buy them singly of course) and use it with suitable plain packing pieces.
|Cabinet Enforcer||09/10/2021 11:33:49|
|107 forum posts|
When cutting smaller pieces on the bandsaw I usually just use some packing pieces from the offcuts left on the saw.
However my next roundtuit will be spent on one of these, which is the most elegant solution I have seen for a bandsaw vice:
Edited By Cabinet Enforcer on 09/10/2021 11:34:39
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