Half Length Parallels?

This may be a bad idea for reasons I don't know. I have a mill, but no place to put it and absolutely no experience with it, mill vises, or parallels.
Why not magnetize thin parallels so they stick to the vise?


Steve Shannon, P.E.

I have never used one or even seen one in person but you can buy magnetic keepers on Ebay.
http://www.magkeepers.com/
 
I would think that cutting parallels in half would cause them to warp, though not much in the wide plain.
Have made numerous sets of soft parallels with whatever dims. were needed on the surface grinder.
So long as you don't try to beat them into the vice they work fine.
 
I use an old magazine spring from a Remington 700 to hold parallels apart. It's shaped like a "W", and has a wide range from 1/4" to 3".
 
Hello, in his Milling book in the workshop practice series Harold Hall shows a good method for making your own parallels. I think it would work very well for anybody, its not difficult so anybody could make any size/thickness. I Am puzzled by the gap at the base of the jaws of the vice - I understand why its there but why does it have to be so wide ?
 
Re gap at base of vise jaws, cant answer that. A wild guess is maybe related to the jaws being a prismatic shape? ie. if designed to clamp vertical depth of X (about 1.5" in my case?) then the fat end of jaw insert becomes quite thick if extended to the very base. I know many vises typically have rectangular jaws so same thickness all the way down. Maybe someone has a better answer. All I can say is this vise is very satisfyingly accurate. Not just in terms of squareness & parallelism. I did the same clamping lift/distortion test I've seen displayed on other vises & it varied from zero to 0<.0005"under load. Negligible in my shop.
 
Why not try adjustable parallels? The small ones are less than two inches wide. I use these most of the time now except when the part I am putting in the vise is too thin.
 
Hi Swarfmaster. Maybe these sketches better illustrate. Black = vise base, blue = parallels, grey = part, orange = through drill. When 6" length parallels overextend the vise bed, they kind of want to flop down based on cantilever center of gravity. So shorter parallels are preferred because they similarly come in matched pairs & incremental width pairs just like the bigger brothers. 29$ for a 10-pair set of 3" is reasonable to me.

I guess a pair of shorter length adjustable parallels might do the same job. The disadvantage is maybe less contact area with part & vise because upper/lower wedges are extending and possibly interfering with each other depending on the setup. I think my own adjustable set is nominally 3-4" long probably would work. Guess I never thought of that. :)

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