[JohnToner]

I have sets of Chinese parallels in 1/4" and 1/8" that I've used for the past 8 or 10 years, no problem (except that they are only parallel w/i ~ half a thou as they were from the day I bought them. I've had good intentions to grind them, but as with my other good intentions, never got around to it.

John

[mike sr1]

I have sets of Chinese parallels in 1/4" and 1/8" that I've used for the past 8 or 10 years, no problem (except that they are only parallel w/i ~ half a thou as they were from the day I bought them. I've had good intentions to grind them, but as with my other good intentions, never got around to it.

John

Those "Roundtuits" are hard to find I must admit ha!

[FuriousGeorge]

The 5/8" parallels have bowed by about 15-20 thou in the middle (image below), and I have no idea how. The weird part is that they were all fine out of the box, but after very minimal use, they are completely out of whack.

Does anyone have any thoughts on 1/8" vs 1/4" parallels? Most of my work is rather small, so 1/8" parallels seem to make more sense, but I'd rather not waste my money if they'll just warp like my old ones.

[mike sr1]

The 5/8" parallels have bowed by about 15-20 thou in the middle (image below), and I have no idea how. The weird part is that they were all fine out of the box, but after very minimal use, they are completely out of whack.

Does anyone have any thoughts on 1/8" vs 1/4" parallels? Most of my work is rather small, so 1/8" parallels seem to make more sense, but I'd rather not waste my money if they'll just warp like my old ones.

The pic didnt come thru George.
If they are out edgeways you would have to do some super hammering to bend them in that direction. I could see it if there was something in the vise under the parallel when it was hammered down.
I make sure everything is clean and that they sit square to the stock before clampning, then hit the part to seat it. Are there any visible dings in the surface of them?
What are you using to check them, that needs to be a machined surface mill table etc.

[twocik]

George,

Harbor freight parallels ?

[FuriousGeorge]

Mike,

Sorry about that, lets see if this pic works. There are a few minor scratches in them, but no major dings. My guess is that some grit got between them when I put them back in there case. Maybe not the best scenario, but I certainly wouldn't expect it to warp a parallel to the degree I'm seeing.

I have measured them by placing them on a stone, holding down the ends and putting a feeler gauge under the middle. Some are as much as 8 thou off this way, which is totally unacceptable.

[IMG][/IMG]

twocik,

I wish I got harbor freight parallels, maybe they still woulda warped, but I would have been out a bit less money!

[Steve Seebold]

Mike,

Sorry about that, lets see if this pic works. There are a few minor scratches in them, but no major dings. My guess is that some grit got between them when I put them back in there case. Maybe not the best scenario, but I certainly wouldn't expect it to warp a parallel to the degree I'm seeing.

I have measured them by placing them on a stone, holding down the ends and putting a feeler gauge under the middle. Some are as much as 8 thou off this way, which is totally unacceptable.

[IMG][/IMG]

twocik,

I wish I got harbor freight parallels, maybe they still woulda warped, but I would have been out a bit less money!

You can put a spring between them that will serve a dual purpose. It will straighten them out and it will hold them in place.