# Will this work for parallels?



## tonydi (Jun 11, 2020)

I recently bought a new 3" toolmakers vise and the jaw depth is larger than the old vise I had.  I have a set of 3" parallels that I've used for years but the largest one is 7/8" tall.  Since I often mill pretty small parts I really need a pair of taller parallels.  I could buy a full set of 6" ones but I couldn't use about a third of them because they're taller than the vise jaws.  Seems like a waste of money.

I've searched around and people talk about making their own but I don't have access to all of the processes outlined (hardening, surface grinder, etc).  But I did see a couple of people talking about just buying ground stock and cutting it into pieces.

Here's a piece of O1 ground steel in 1/8" x 1".
https://www.mcmaster.com/9516K47-9516K213

Would this work, would these be easy to cut with a bandsaw or Dremel cutoff wheel?  I'm not sure I really need them to be hardened but I would like them to at least be as accurate as the parallels I currently have.


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## mmcmdl (Jun 11, 2020)

You could always just put some key stock or whatever you have below your existing parallels to raise them up .


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## hman (Jun 11, 2020)

I've cut O-1 with my 4x6 bandsaw, no problem.


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## mikey (Jun 11, 2020)

One option you might consider is to buy a set of ultra-thin parallels in 6" length. These go up in 1/16" steps, which is super-handy when you need to position a part precisely. You could use your 3" parallels for most work and use the taller ones as needed from the thin set. These thin parallels also allow you to drill very close to an edge, which can be a major advantage at times.


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## tonydi (Jun 11, 2020)

mikey said:


> One option you might consider is to buy a set of ultra-thin parallels in 6" length. These go up in 1/16" steps, which is super-handy when you need to position a part precisely. You could use your 3" parallels for most work and use the taller ones as needed from the thin set. These thin parallels also allow you to drill very close to an edge, which can be a major advantage at times.



Thanks, Mike, but that is less cost effective than the smaller sets I was talking about because almost half of the parallels will be taller than the vise jaws.

I really just need one pair of 1" and I'd be set, especially considering that I've gotten by with only 4 pairs in all the years I've had the mill.

@mmcmdl I actually tried stacking another pair of parallels under my 7/8" pair.  I ran into two problems.  One, the first time I needed to do that the part I was machining was thinner than the width of my smallest parallel so I couldn't close the vise jaws enough.  If I had some smaller material that was close enough tolerance not to affect the milling operation I'd still run into the problem that anyone who has used one of these screwless vises knows all about.  It's a bit of work to get everything situated and get the moveable jaw into a position that clamps properly.  When I was able to stack another parallel underneath the 7/8" parallels they kept wanting to fall off or tip over.  Too many moving parts and not enough hands!  

@hman  Thanks for that.  I've used W1 and it's easy to cut but didn't really know about O1.  The specs say that ground bar is +/- .001, which isn't all that good compared to the .0002" typically called out for parallels.  But I was thinking maybe that spec is for the 1/8" thickness and not width.  I'll need to check that out.

(Edited to add) Oh shoot,  I just saw this *Width Tolerance 0" to 0.005".  *Now if that's just how far it might vary from 1" on any particular bar, like one bar might be 1.000 and another 1.003 or 1.005, that's fine.  What I don't know is the tolerance on the parallelism.


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## Lo-Fi (Jun 11, 2020)

I have a set of thin parallels like Mikey suggests, I'd be quite lost without them. Definitely worth an investment even if you don't use some of them. I quite often use the larger ones on their sides as thin packing shims in setups, they're really handy.


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## T Bredehoft (Jun 11, 2020)

If you buy 12 inches of 1/16 by 1 inch O1 flat stock, and cut it in half, the two ends will be the same witdth.


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## brino (Jun 11, 2020)

@tonydi,

I believe that "Width Tolerance    0" to 0.005" " is over the entire 18" bar.
Any 3" section you cut from it will be way better than that.
I think your first suggestion/question is the best solution.

-brino


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## Alcap (Jun 11, 2020)

Reading this thread has me thinking how handy it would be to have a custom set of parallels . Since I don't have a surface grinder could I just set the steel in a vice and machine them to the size I wanted , wouldn't have as nice of a ground finish but should be able to get them parallel by milling correct ?


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## ThinWoodsman (Jun 11, 2020)

Alcap said:


> but should be able to get them parallel by milling correct ?



Think of it as the milling equivalent of making a center in the chuck - that center will be perfectly true, until it leaves the chuck


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## Buffalo21 (Jun 11, 2020)

I find the subject of parallels interesting, for the Rockwell mill with a 4” mill vise, I wanted a set of 1/8” x 4” parallels. Everyone seemed to sell 3”, 6” and larger, but almost no 4”, I did find a set of 4” ultra thin wavy ones, that I bought, I still wanted the 1/8” thick. One of the vendors had a set for about $250, BangGood had a set for $80 (plus the wait) and LMS offered a set for $45, but seemed to be out of stock, continuously (finally came in and have been ordered). I found it interesting, with all of the small mills out there that 4” parallels, were so hard to find.


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## RJSakowski (Jun 11, 2020)

I used O1 for parallels for decades.  I didn't bother with hardening.  I still use them for various setups.  1/2 x 1", 3/8 x 3/4", 1/2 x 1/2", and 1/4 x 1/2".


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## benmychree (Jun 11, 2020)

I have a set of parallels that I use on my shaper that are 0-1, that are about 1-1/2 X 2-1/2 X 12 that I have been using for perhaps nearly 50 years now, they have gone through 3 different shapers over the years; they are not so hard of course as the real thing, but even after all those years, they are still in nice condition.


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## extropic (Jun 11, 2020)

If you search eBay for "parallels", then reorder the results by lowest cost first, you may find an option(s) that will meet your requirements.


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## tonydi (Jun 11, 2020)

extropic said:


> If you search eBay for "parallels", then reorder the results by lowest cost first, you may find an option(s) that will meet your requirements.



Thank you.  I followed your suggestion but didn't find anything that I hadn't already seen and rejected before.

However, I now have another wrinkle in what should have been a simple thing.

I went out in the garage to take some measurements and noticed the vise has this weird groove in the base right against the fixed jaw.  No idea why it's like that but it's more than 1/16" wide so going ultra thin is completely out.  And it's _really_ close to 1/8"  so even a parallel that size will probably have trouble staying up on the main vise surface.  I measured my current parallels (which work) and discovered that they aren't even 1/8" like I thought, but 5/32".   So I'd have to get 5/32" O1 bar and hope that it has good specs.

Maybe at this point I'll go back to the idea I had initially and which @mmcmdl suggested and find something to put under my current 7/8" parallels.


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## mmcmdl (Jun 11, 2020)

We improvise and get by in the shop all the time .


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## extropic (Jun 11, 2020)

It seems I don't understand your particular requirements for parallels. Good luck.

The " weird groove in the base right against the fixed jaw " is called a corner relief. It's purpose is to allow grinding both perpendicular surfaces without the wheel edge (corner) being jammed into a corner. Very common feature.


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## tonydi (Jun 11, 2020)

extropic said:


> It seems I don't understand your particular requirements for parallels. Good luck.
> 
> The " weird groove in the base right against the fixed jaw " is called a corner relief. It's purpose is to allow grinding both perpendicular surfaces without the wheel edge (corner) being jammed into a corner. Very common feature.



Ahh, ok, thanks!  In my vast experiences with vises (only had one before now) I'd never seen it.

As far as my requirements, I just need a pair about 1" tall x 5/32" thick.  I don't want to spend $50-$60 to get a 6" set for a 3" vise and have half be duplicates of what I already have and the other half be too tall for the jaw depth, just so I can get 1 pair that fits my needs.


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## Buffalo21 (Jun 11, 2020)

My milling machine vises do not have that groove, but my drill press vises do....


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## westerner (Jun 11, 2020)

mmcmdl said:


> We improvise and get by in the shop all the time




As to needing 4 hands to get a setup going- 

One drop of oil on each side of the flat of the parallel will make it 'stick' to the vise jaws. 
Some fellas use springs (compression) to hold the parallels tight to the jaws as you change out your parts.
Either approach will reduce by at least one, the amount of hands required to get set up.


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## mmcmdl (Jun 11, 2020)

Yep . Double back tape comes in handy sometimes also .


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## darkzero (Jun 12, 2020)

Buffalo21 said:


> My milling machine vises do not have that groove, but my drill press vises do....



Milling vises that have a fixed jaw that can be unbolted won't need that relief. Vises that have a fixed jaw that is one piece with the base, like the tool makers vise pictured above, will need that relief in order for grinding like extropic mentioned.


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## ThinWoodsman (Jun 12, 2020)

westerner said:


> One drop of oil on each side of the flat of the parallel will make it 'stick' to the vise jaws.


Petroluem jelly also. Works like temporary glue for wringing parts together, even when they're not so smooth. Kinda like, well, doublestick tape.


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## tonydi (Jun 12, 2020)

ThinWoodsman said:


> Petroluem jelly also. Works like temporary glue for wringing parts together, even when they're not so smooth. Kinda like, well, doublestick tape.



Yeah, I think this or the oil would work better for me.  I use some double-stick masking tape for certain jobs and it works great but often times I find myself switching parallels during the milling of a part so that would be a pain with the tape.


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## intrepid (Jun 18, 2020)

How about these from LMS?   https://littlemachineshop.com/products/product_view.php?ProductID=3946&category=
They also have a couple other 3" sets as well as 6"


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## tonydi (Jun 18, 2020)

intrepid said:


> How about these from LMS?   https://littlemachineshop.com/products/product_view.php?ProductID=3946&category=
> They also have a couple other 3" sets as well as 6"


Yeah, I saw that set and thought it would at least give me the 1" I need and I'd have other smaller sizes that I don't already have.  So I wouldn't consider it a $42 pair of 1" parallels.

But those are 1/8" and here's what a .125" piece of stock looks like up against the fixed jaw.  So little sitting on the vise itself seems sketchy to me. Right now I'm using 5/32" x 3" LMS parallels and that's the only 5/32" set they have.


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## mattthemuppet2 (Jun 18, 2020)

I have a 4" vise and as others have noted, most of the parallels will be too tall soI made most of my parallels from precision ground stock bought cheap off amazon. They're a mix of A36, O1, A2 and D something. Cut to length on the bandsaw and the left overs stuck in the stock drawer. I haven't hardened the ones that can be hardened as it's kind of neat being able to make a whoopsie (drilling typically) without screwing up the tool. A quick pass with a file and any burr on the parallel is gone. If any of them get too swiss cheesy I'll simply cut another one.


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## theperfessor (Jun 18, 2020)

Are the jaw pads replaceable? Rather than screw around making parallels I'd make taller jaw pads. then I would buy a cheap set of 6" parallels on Ebay or somewhere and cut them in half  and use the short ones with the factory jaws and the taller ones with the tall jaws. We make special tall jaws for our Kurt for certain jobs.


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## tonydi (Jun 18, 2020)

theperfessor said:


> Are the jaw pads replaceable?



No, if you look up at post #15 you'll seen it's all one big piece.  I think all of the screwless/toolmaker's vises I've seen are like that.

@mattthemuppet2  Yes, in fact that was the idea that started this thread!  I just wasn't sure that type of material was ok and if it had parallelism that was good enough.  I can find precision ground steel on Amazon but nothing I'd call "cheap".  I'll need to dig deeper.  I also didn't see the need to harden these either.


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## mattthemuppet2 (Jun 19, 2020)

use jungle search and be patient. I think I accumulated my various bits'n'pieces over a couple of months. 5 separated orders, came to around $40 or so.

Here's one good option if 1/8" is good:





						Amazon.com: D2 Tool Steel Sheet, Annealed/Precision Ground, ASTM A681, 1/8" Thickness, 3/4" Width, 18" Length: Industrial & Scientific
					

Amazon.com: D2 Tool Steel Sheet, Annealed/Precision Ground, ASTM A681, 1/8" Thickness, 3/4" Width, 18" Length: Industrial & Scientific



					www.amazon.com
				




I know you stated a need for 5/32, so that might take a bit longer (though one of mine, the 1/2" one I think, is 5/32), but you'll get there eventually.


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## tonydi (Jun 19, 2020)

mattthemuppet2 said:


> use jungle search and be patient.



Wow, never heard of Jungle Search!  Thanks, I'll try that out.  Even that 1/8" stuff you linked to is more $$ than the McMaster-Carr piece I originally asked about.  But as this quest has gone on, one of the things that has come up is that even these "tight tolerance" pieces have a 0.000-0.005" tolerance in the width.  So it would be a crapshoot as to whether or not I'd get something that was usable as a parallel.  Even the cheapie LMS set that I have are 0.000-0.0001".


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## mattthemuppet2 (Jun 19, 2020)

I'm not sure where you're looking, but $11inc. postage for 1 1/2ft of 1/8x3/4" D2 (or A2 or O1) is a pretty good price.

eg. https://www.mcmaster.com/88905K56-88905K132 = $32 before shipping.

The specs I founds are +/- 0.001". I generally struggle to work to less than 0.001" when milling and even on the lathe that level of precision is not trivial, so those specs are good enough for me. Only you can decide if you need better than that.


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## tonydi (Jun 19, 2020)

I need 1" wide.  That's this one and it's $22.47. The specs say "Item Width Tolerance +0.000/-0.005 inches" That's the same tolerance of the 7/8" one you linked to.

Plus, it's 1/8" wide and they don't offer a 5/32" version of that one.

I agree with you and I'd take 0.001" any day and twice on Sundays.  But that doesn't seem to be available in any tight tolerance precision ground stock.


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## mattthemuppet2 (Jun 19, 2020)

you know it's funny as I actually looked up and read the ASTM 681 (?) spec sheet for precision ground tool steel as I wanted to understand what that tolerance meant. As far as I could tell it's a "to specifications" tolerance ie. if the piece is listed as 0.750" then it has to be within 0.749 and 0.751". It's not a paralellism tolerance or a "by length" tolerance, so it could be wavy by 0.002" all the way along and be in spec. I would guess though that what it really means is that if you order a 0.750" wide piece, it will be 0.749 or 0.750 or 0.751 all the way along the piece, but if you bought a second piece they only guarantee that it would be within 0.749-0.751, not that it would be the same width. As you're buying one piece and cutting it into smaller pieces, that doesn't matter.

The Amazon listing has ASTM 681 in there, so my guess is that the width tolerance they listed is an error or for larger widths.

As I said earlier, you need to be patient if you want to get the good prices. If you need it right now that can bump the cost. For me the total came to about what a cheap import set of 6" parallels costs, but I have more confidence in the parallelism and matching of the ones I made.


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