A couple weeks ago, I greased her up the screw is comming out but not the jaws if I pull they come apart easy and screw in what part mite I need.

If it is a post vise you are talking about then it sounds like the leaf spring is either missing or needs adjusting or has simply come loose. Can you post a picture to help identify the problem please?

If you grab the jaw and pull does it move? If it is a post vise, and it does not move, loosen the pivot bolt. You can re-tighten after cleaning and lubrication.

Phil

chevelle69,
My first post vise I bought off of ebay and it was just the vise -no mount, no spring, and frozen solid. But hey, it was $40 for a 75 pound vise and I was so happy to find one reasonably cheap. I spent a week or two dumping every type of rust killer on with no luck. I eventually hoisted the thing on my forge, buried it in coal and roasted it free -works great. That being said, I do not believe that is your problem. I believe you either need a spring to take up the slack when the screw opens or you need to modify your mounting angle so that gravity works for your advantage. That is what I did with mine, it works great and I did not have to find or make a spring. If you chose to make a spring, a bit of caution, look at designs out there and make sure you put spring behind the mount. An unsecured spring would be dangerous. Also make sure the front section has some dog ears on it, otherwise it might end up slipping and causing some physical pain.

If I unscrew it it just spins all the way out the jaws don't open but I can pull apart easily with it unscrewed but can't pull open if screwed in,the part of the jaws that open on the inside of it where the screw part is seems like there should be something there to help with the jaws to open maybe not? There is nothing there hope you can under stand my bla bla bla Try this one Sorry guys that wasn't mine that was a pic I got off Internet this is mine I'll check the spring tomorrow and let ya know my findings thx.

Maybe your spring or spring system is not producing enough force to open the jaws. Unless I am misunderstanding you, it sounds like the threads on the screw and in the box are good since "can't pull open if screwed in" and that it can unscrew.

The two post vises that I have, with springs, have tension on them from the spring frocing the jaws open. Have you tried pushing the jaws together when the screw is in the open position? Is there tension created by the spring?

Your mounting is pretty short, and the spring is pushing very close to the pivot. I had this problem with my old work table being too low. Your choices are make a new spring, or find a means to move the mount up so the spring pushes a little higher, farther from the pivot.

You can also bend the spring some so it exerts more force. Since most post vise springs are mild steel this is pretty easy to do cold.

Phil

Phil, I agree the spring is really close to the pivot. My guess is that the custom mount is not holding the original distance needed for tension. The rear leg being tapered causes the tension to lesson the farther down you go as a result of the increasing the distance. Another guess is that mount is allowing for the spring to rotate on the x axis (actually a) and not hold tension, but hard to say the picture is small.

That is possible. On my workbench the mounting was low, and the spring never stayed put, but the vise was mounted to the table away from a leg so it was a whole lot less solid that it should have been.

Phil

Ok when the screw is all the way backed out, I can pull the jaws open and closed all day long with no resistence that's not good.

you need more bend in your spring or a new spring. bend the spring till it keeps tension on the front jaw leg.

The spring is supposed to be strong enough to open the jaws when set up properly. You should still be able to close the jaws easily by hand without using the screw.

Your mounting looks OK in the new pictures, but your spring is weak. Take the spring out and carefully bend it some more, cold. The spring is typically mild steel.

Phil

Is there suspose to be something on this side of the pic were I have it aimed ?

Nope. It is sloppy greasy, over greased. (you probably should remove the extra with a rag, it will collect dirt and scale, then become abrasive) The screw box is visible, the screw is visible. That is it.

Unlike a machinist vise, a post vise does not get opened by the screw, only closed. The spring does all the opening, the screw does all the closing.

Phil

Thx over greased yea I would have to agree with that

just went to the shop and checked mine. my spring is about an inch and a half above pivot point and opens fine. i agree that perhaps the spring needs attention.

I see ton's of grease/oil up on the screw but NONE on the cheeks and pivot point.

Did you remove the screw and then the pivot point bolt and take the moving leg off and cleaned off any rust on the inside of the cheeks of the pivot point and on the moving leg portion that goes between the cheeks of the pivot point? (and make sure the pivot point bolt is not over tightened---the nut is just there to make sure the bolt downs work itself out and fall on the ground NOT to tighten the cheeks!)

If the moving leg bearing faces are too rough or overtightened it doesn't matter how good a spring you have it still won't open!

(and I have seen vises where the spring has been mounted upside down with a custom made spring bracket to apply force with a longer lever arm...)

Hey guys thanks a million she's up and working I wiped of excess grease (I should had known that one) will grease the other parts I rebent the spring works great I should have known that part also but it's better to ask ?s now that I'm out of school thxs to all this is a great site ;)

Glad to hear that it is working, but your spring is in upsidedown to how mine is mounted.

So is mine upside down?

Or mine is!

So it is mounted like in picture 1 and not in picture 2? Picture 2, on the stand, is the correct way, picture 1 is upside down.

Phil

The "correct way" is the one that works in your situation.

In general the spring is mounted to fit into the mounting bracket just under the screwbox with the extended part resting on the lower section of the side of the moving leg of the vise.

I have seen them done in a variety of ways due to special circumstances---including one post vise that used a coil spring!

Making a spring for a leg vise is a common task and they can be made from mild steel as long as they are designed to not exceed the set point of the steel. (spring steel can bend farther without taking a set but can also break if not handled correctly. As new smiths are often not familiar with proper forging and heat treat processes using a mild steel bar can get a working vise a lot faster and with less frustration. You can also take a mild steel spring off and re-spring it cold if it's not quite to proper form.)

I knew I should have written "correct" with the quotes...

Phil

New people so often believe everything we tell them---why several believe I have a corporeal existence and am *not* a cyborg!