Half Length Parallels?

petertha

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I find myself setting up smallish parts in the mill vice where I'm drilling through or slotting through and therefore cant have the parallel contacting the underside of part in the break-through area. I'm talking narrow-ish width parts with a single parallel setup or using 2 parallels on either jaw but insufficient clearance for drill to clear between them. If I use my standard 6" parallels with a gap in the middle, it works, but they usually overhang my (4-5" width) vice bed on either side quite a bit kind of want to cantilever the part upward under their own weight until the jaws are secured.

What I thought would be a good thing is a 6" set lopped in half. Of course they don't make them & doing this on hardened steel is probably not fun. Which tells me I must be thinking about this problem wrong! I though about just getting some ground rectangular tooling stock but for the price of a 18" stick of a specific size, I can buy an entire set of Asian parallels. Thoughts or recommendations?

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Why not? Parallel sets are cheap. Cut them with an abrasive tool, an abrasive chop saw would work great if you have one, or maybe it's time to get one if you don't have one;)

The other option would be be thin parallels, but those are expensive.
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FYI - I saw ENCO had a set of 3.5" long Import thin parallels for reasonable amount recently. I have a 4" vice so, was thinking of adding them to the collection. No need to cut long ones.
 
I actually have a set of el-cheapo... I think they are 1/32" thick parallels. Probably from same 'red-plastic-case' factory that made my 1/8" & 1/4" set. They work too & from what I can tell are ground accurate. But they don't have a lot of self 'stand-up-ability' (how's that for technical term). Part of that is my vise jaws have an undercut viewed from the side. I've heard people put some oil on the face & they tend to stick to the vise jaws better.

Anyway, maybe I will just get the abrasive grinder out, lop a scrap parallel in half, dress any burs & keep them in a separate box of hack fixes. Just thought I'd ask first in case there was an obvious old school toolmaker solution that completely flew over my newbie head.
 
Oops, posted too soon. Thanks guys I'll check those shorty's. Was not ware of those!
 
I have the 3" long parallel set from LMS and they work fine but they are 1/8" thick. You need thin parallels, 1/32" thick and those only come in 6" lengths as far as I know. There are also wavy parallels that stand up on their own and are often used singly.

If you want thin parallels to stand up and don't want to use WD-40 or something to stick them to the vise jaws then use a piece of closed cell foam between them. This will hold them tight to the jaw faces and free your hands to position the work.
 
The LMS was a good lead. Ordered the less $ import 3-inchers (over a similar USA set they also offer). You're right, they are 1/8" wide but that should work for a lot of my setup applications as part is > 1/8" parallels can be spaced apart laterally to allow a center gap clearance & still rest on the vise ways.

Got these while I'm at it - 1/16" wide & shorter length.
http://littlemachineshop.com/products/product_view.php?ProductID=3947

Awesome feedback guys, that saved me some hacks.
 
I have the 3" long parallel set from LMS and they work fine but they are 1/8" thick. You need thin parallels, 1/32" thick and those only come in 6" lengths as far as I know. There are also wavy parallels that stand up on their own and are often used singly.

If you want thin parallels to stand up and don't want to use WD-40 or something to stick them to the vise jaws then use a piece of closed cell foam between them. This will hold them tight to the jaw faces and free your hands to position the work.
I have a few feet of closed cell foam pipe insulation that I use to keep the parallels tight to the jaws. I cut off several pieces thicker and thinner that can do about anything I want. The pipe insulation is also split and the cutoffs can be twisted for some jobs. Great stuff, and it was FREE!
 
The foam is a good idea, will note that trick. I like my Bison vise a lot but one aspect is the jaw bottoms seem a bit high relative to the slide base. I don't have another vise to compare, but it kind of seems that way. So thin parallels in the smaller range like ~1/2" tall can have a tendency to roll into this gap when setting up work pieces. But if the foam was almost the same height as parallel's it probably would exert a nice soft even force.

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