# Half Length Parallels?



## petertha (Mar 13, 2016)

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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## JimDawson (Mar 13, 2016)

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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## sbx (Mar 13, 2016)

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.


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## bill stupak (Mar 13, 2016)

Try Little Machine Shop, they have a few different sizes.


http://littlemachineshop.com/products/product_search.php?critFast=parallels&B1=Product+Search

Bill


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## petertha (Mar 13, 2016)

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.


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## petertha (Mar 13, 2016)

Oops, posted too soon. Thanks guys I'll check those shorty's. Was not ware of those!


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## mikey (Mar 13, 2016)

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.


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## petertha (Mar 13, 2016)

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.


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## Bob Korves (Mar 13, 2016)

mikey said:


> 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!


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## petertha (Mar 14, 2016)

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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## stupoty (Mar 14, 2016)

I've used a bent cut down old hacksaw blade as a spring to keep the thin parallels against the jaws, saw it somware on the internet and lodged it in the memory for future use, good idea to run a grinder over the teath first 

If your going to cut down the parallels they might not provide such good support, I guess it depends how the slide on ur vice is designed.

Stuart


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## Billh50 (Mar 14, 2016)

I have a set of thin soft parallels that were made by just cutting up some flat ground stock. As long as I take care when using them they have been fine. I use a bent piece of shim stock or 2 springs to hold them against the vise jaws depending on what I am doing.


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## Bob Korves (Mar 14, 2016)

Banding material from tying packages to pallets is also useful as parallel spreaders.  There are different widths out there, and it is springy yet easy to bend.  I have never tried to machine it, but it would probably be easier on tools than hardened parallels.  It cuts easily with tin snips.  It bends easily for use as springy wavy parallels as well.  It is also FREE to scavenge.


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## Steve Shannon (Mar 14, 2016)

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.


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## David S (Mar 14, 2016)

I just have some pieces of low density foam rubber that I put between them.

David


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## T Bredehoft (Mar 14, 2016)

Magnets are OK if working aluminum, but steel chips will stick to everything on the mill table if magnets are used anywhere near the work.


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## Steve Shannon (Mar 14, 2016)

T Bredehoft said:


> Magnets are OK if working aluminum, but steel chips will stick to everything on the mill table if magnets are used anywhere near the work.


Thanks, that makes perfect sense, of course. 


 Steve Shannon, P.E.


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## bill stupak (Mar 14, 2016)

For spacing parallels I use these clips. They're used for metal picture frames, you can get them at a good craft store like Michael's or AC Moore. They measure about 2 3/4" and have a range of 3/4".

Bill


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## T Bredehoft (Mar 14, 2016)

bill stupak said:


> For spacing parallels I use these clips. They're used for metal picture frames, you can get them at a good craft store like Michael's or AC Moore. They measure about 2 3/4" and have a range of 3/4".
> 
> Bill
> 
> View attachment 124785



Great Idea.  And you can rivet any number of them together back to back for wider spacing. ....


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## uncle harry (Mar 14, 2016)

Steve Shannon said:


> 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.



The only flaw that I can think of is the possible PITA of attracting swarf.


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## Steve Shannon (Mar 14, 2016)

Yeah, it could end up looking like one of these:




 Steve Shannon, P.E.


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## Badspellar (Mar 14, 2016)

Steve Shannon said:


> 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/


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## tertiaryjim (Mar 15, 2016)

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.


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## derf (Mar 16, 2016)

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".


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## BillWood (Mar 19, 2016)

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 ?


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## petertha (Mar 19, 2016)

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.


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## stevemetsch (Mar 20, 2016)

How about a pair of new coins to use as your parallels???


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## petertha (Mar 22, 2016)

I received my LMS 3" long parallels today. Super fast shipping to Canada. They are very nice quality, accurate dimensionally/matching, decent wood case, good price. Exactly what I need. Thanks for the suggestion!
http://littlemachineshop.com/products/product_view.php?ProductID=1893&category=


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## Swarfmaster (Mar 23, 2016)

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.


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## petertha (Mar 23, 2016)

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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