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[Newbie] Vise pressure

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dale3943

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I am looking at buying a two ton arbor press which has me wondering how much squeezing pressure my 5" vise can generate. I've found a vise is a good way to press small jobs together but the force generated seems to be fairly minimal. Could anyone please point me towards somewhere i could either look up or calculate the vise pressure information.
Thanks

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Moderatemixed

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Just to add to your post, I had wondered the same. In the end I bought a 3 ton arbour press (a Greenfield). I have an Emmert, a Wilton and a Richards Wilcox bench vice, all of which can (and have) been used for various “pressing” operations, and have slightly different thread forms related to their intended purposes. I believe that it comes down to the screw vs rack and pinion and the leverage etc. You could work it out with a Machinery’s handbook if you broke the mechanical elements down. That said, as I understand it, the vice is for work holding (primarily) and as such the screw is designed to hold whereas the rack and pinion is just a couple if opposing levers..... It’ll be interesting to hear what the “pro’s” have to say though. Cheers


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ErichKeane

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Kurt lists their workholding force on the website. I don't have info for the 5" (since Kurt only has a 4 and 6 on their website), but these are the numbers for those:



Torque Ft. Lbs.D40
101653
202923
304103
405241
506513
607807






Torque Ft. Lbs.D688
10512
201487
302464
403440
504415
605391
706367
807342
 

RJSakowski

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It depends entirely on the thread pitch and the length of the lever. The screw is an inclined plane and it is possible to calculate the mechanical advantage from basics. I prefer to take a more simplistic approach. Using the fact that force times distance applied by me is equal to force times distance equal to force times distance at the jaws.
My main shop vise has a 4tpi lead screw.so the jaws move 1/4" with each complete revolution. With an 8" lever, my arm moves through a distance of about 50" (8 x 2 x 3.1416). My mechanical advantage is 200 to 1. If I apply my 200 lbs. to the lever, I am looking at 40,000 lbs. at the jaws. Now this is a simplistic view and doesn't take into account friction but the point is that there is a tremendous amount of available force.
I have used the vise for pressing bearings and for broaching holes. The biggest problems are the short working distance and keeping everything aligned in the process.
 

benmychree

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I would look at the myriad of bunged up vises that were at one time, "top of the line", the bent handles, cracked slides, etc. the question is, do I want to keep my vise in good condition by treating it to the level that it was designed for, or take the chance of breaking something or springing it out of alignment; vises are for workholding, presses are for pressing. Also note that a lot of more modern vises are much less robust than their ancestors.
 

randyjaco

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Get the proper tool for the job. Your vise was not designed to be a pressing tool. You might as well use a hammer :eek:
 

MalR

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Jan 2, 2018
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I made a small load cell by connecting a mini 4-ton hydraulic cylinder to a pressure gauge then tightened the cylinder in my 4-1/2” vice. At what I regard as max torque - my weight on the handle - it reached 1 ton.

Mal
 
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