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Go to ebay. Search for Vintage Machinist Vise. Your welcome.
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Maybe - nearly 40 years ago when I started learning the machinist / tool and die trade most of the shop Bridgeports had been purchased with Bridgeport branded vises. Great iron but best used for a drag anchor. Those vises could lift a part nearly 1/8". You had to have a collection of lead or shot filled hammers to seat your parts. Delrin, UHMW and most plastics had a good chance of suddenly jumping out of the vise. To drill brass safely you needed a special flat face drill profile or it could grab, snap the drill or throw the part or both.
I have no love lost for the bad old days spending a week grinding out HSS form tools and having to cut slow with black oil to preserve the tool edge. Back then you would cringe when they told you the part needed to be 304 Stainless and not the "L" type (leaded) because the part was a component of a weldment.
The Kurt down force locking design changed the way the trade worked. You could trust a well maintained Kurt to hold accurately almost as good as your machines repeatability. So even cheap Indian, Russian and Chicom knock offs of the Kurt design can be a better choice than old domestic designs. I don't care about crappy paint which dissolves or flakes off when exposed to coolant or cutting oil. I don't care about rough casting areas which were not machined or ground - I have a Dumore die grinder and full collection of burrs to detail race engine blocks if its bad enough I'll fix it.
( before putting a vice or other heavy iron or steel object on a surface plate, stone all the contact areas which will touch the surface plate. )
The key points are:
- Base has been ground parallel and flat to jaw ways. I use a tenth reading indicator on a old style surface gage. If more than 0.0002" variation is found vice is marked for rework and out of cert.
- Solid jaw is checked to be square to jaw ways within your chosen spec. Note that the jaw can be less than 90º but not greater than 90º. When it is less than 90º the vise is commonly tightened to a known torque value with a calibrated click type torque wrench which will flex the vise to the point that the jaw is at near perfect 90º
- Solid jaw is also checked to be square to the motion of the jaw.
- Moveable jaw face should be parallel planer to the solid jaw within your chosen spec.
- Vise back bending should be tested by mounting a 6" known flat HSS tool bit in the vise square to the base clamped very lightly and a tenth reading indicator reading off the upper edge. Vise is then tightened to full working torque. Observe if the vise is flexing under torque load. (This is usually done bolted on a mill or surface grinder table.)
Note: All tests but the torque test are done with jaws removed. Torque test is done with a pre tested for flatness hardened jaw set.
Today I love working in most stainless, and keep some 4140 pre hardened handy for all sorts of needs.
Note also - I love surface plates - I have one for each workstation in my shop. For inspection I have a Mititoyo black and a Starrett Pink, most of the workstation units I bought with the 25% off with free truck shipping discount codes from Enco ( use-enco.com ) - These codes still happen about every 3 months so have your wish list ready. You will need to sign up for the Hot Deals sales fliers to get the codes and use a user name and pass when ordering online but its well worth it.