Sets of parallels

[Chris MateParticipant @chrismate31303]

Hi, my new vice jaws are 29mm high. The place I usually buy stuff from has two sets of parrallels 1/4" & 1/2" thick. However the hights confuse me a bit, most of the set will be too high for the jaws.

Is this normal, meaning you can use those that too high for vice with the clamping set to the table as well-?

Or should I just buy individual parallels(in pairs) from another shop less than 29mm only for vice-?

Contents include:
-1 Pair of 3/4 X 6 X 1/4″ (Hole: 5/16&Prime
-1 Pair of 7/8″ X 6 X 1/4″ (Hole: 5/16&Prime
-1 Pair of 1″ X 6 X 1/4″ (Hole: 5/16&Prime
-1 Pair of 1-1/8″ X 6 X 1-4″ (Hole: 3/8&Prime
-1 Pair of 1-1/4″ X 6 X 1/4″ (Hole: 3/8&Prime
-1 Pair of 1-3/8″ X 6 X 1-4″ (Hole: 7/16&Prime
-1 Pair of 1-1/2″ X 6 X 1/4″ (Hole: 7/16&Prime
-1 Pair of 1-5/8″ X 6 X 1/4″ (Hole: 1/2&Prime
-1 Pair of 1-3/4″ X 6 X 1/4″ ((Hole: 1/2&Prime

[Chris MateParticipant @chrismate31303]

[Speedy Builder5Participant @speedybuilder5]

Its fairly obvious that the set is not for you, there are other sets out there. Its a matter of looking around.

[JasonBModerator @jasonb]

I have several vices collected over time some with taller jaws than others so get to use most of my 1/2" to 2" set, I also regularly use the taller ones for packing up work mounted directly on the mill table or lathe cross slide so although the bigger ones may not get used so often they can be useful to have.

The 80mm versatile that I use on the CNC has the shortest jaws and I just keep one of the economy sets by that which do for most jobs and save having to fetch the main set from the other workshop, only ground on the two edges but that's all you use.

If your vice is reasonably small as the 29mm jaw height suggests you are mostly going to be working on smaller parts so I would suggest the thinner of the two as you will find with a thick parallel in place you can't close the jaws down on it unless additional side packing is added. The wavy parallels are good in this respect as you can squash them right down to almost nothing.

[HOWARDTParticipant @howardt]

Parallels should match width of jaws as well as fitting within the height. Sets usually either 4 or 6 inch, some can be bought as 1/8 th thick set so tend to be lower height.

[not done it yetParticipant @notdoneityet]

I think those that Arceuro sell are metric, but should suit jaws that are metric high.🙂

[BazParticipant @baz89810]

Warco do a nice set that are 100mm long and range from 5mm to 25mm high in various thicknesses.

[Tony Pratt 1Participant @tonypratt1]

You have to buy parallels to suit your particular vice.

Tony

[JourneymanParticipant @journeyman]

You could try these *** LINK *** haven't used myself but might be worth a go!

Going a bit 'off piste'  as it were, I wonder if 3D printed parallels would be any good. Of course these would not be precision or long lasting but might suffice for the odd job and 3D printing can be surprisingly accurate with a good set-up.

John

Edited By Journeyman on 14/12/2021 09:21:45

[Chris MateParticipant @chrismate31303]

Thanks for the advice, I think I settle for 3mm x 150mm 12.5Kg set as example a dealer send me, however the 150mm is not right, so I am trying to get 100mmx 3mm set from them from Vertex(Same as vice).

(I can see I will need the 1/4" or even 1/2" later on for use with the clamp set directly to mill table. In this case I want to make a see through Glass top for lathe with 25mm thick aliminium piece milled to fit a square glass on top with integrated catch plates beneath that to catch the oil and deliver it to the spindle bearings as I have now a mocked up system working with a wood frame and seperate catch plates, no moving parts or bolts that can come loose and fall in gearbox.)

[JasonBModerator @jasonb]

I use 6" on sin my 4" vertex all the time what is not right about that? Also use them in my other 90mm and 80mm and even the 35mm vices when they come out.

Rather than 3D printed ones to get you out of trouble any bit of flat bar or tool bit will do, I managed for quite a while like that.

I'd look for something that allows you to hold work 1mm to 1.5mm below your vice jaws as it's often useful when working on small parts, I'd find the 25mm high set a bit limiting in 29mm jaws.

 

Edited By JasonB on 14/12/2021 09:50:57

[BazyleParticipant @bazyle]

Posted by Journeyman on 14/12/2021 09:15:41:

I wonder if 3D printed parallels would be any good.

Edited By Journeyman on 14/12/2021 09:21:45

I think a decent bit of hardwood would be better. Especially off an old well seasoned furniture. Worth having some around that you can mill down when you want to set something small and need a support just below the jaws.

I think 3D printing might be better for making a compliant (squidgy) custom jaw to grip an awkward shape.

[David CauntParticipant @davidcaunt67674]

Chris.

I made a set of parallels but then found I needed thinner parallels so bought a set of Precision Wavy Parallel 8pc Metric Set from Arc…. They get used all the time.

Dave

[Nicholas FarrParticipant @nicholasfarr14254]

Posted by HOWARDT on 14/12/2021 07:21:35:

Parallels should match width of jaws as well as fitting within the height. Sets usually either 4 or 6 inch, some can be bought as 1/8 th thick set so tend to be lower height.

Hi HowardT, I can't se why they have to match the width of the jaws, as long as they are long enough for the work envelope on the piece you are machining on, where's the problem and like JasonB says, I've got a pair of those that he linked to, at the moment, which are longer than the jaws and the piece they are holding to the correct height.

I have made two pairs, one 16mm high and one 22mm high & 4mm thick, which are 80mm long, these were made from a scrap cast iron baffle from a lorry engine (don't know what it did, but had a nice flat section) which I just milled to the highs mentioned within a small amount, but each pair was milled together, OK, I don't profess them to be precision, but they are the next best thing and they do well for many jobs, but like Jason has said, decent flat bar will do many jobs that don't require precision work.

Regards Nick.

Edited By Nicholas Farr on 14/12/2021 12:26:15

[Tony Pratt 1Participant @tonypratt1]

3D printing is not the way to go, I can't think of anything less suitable for parallels than plastic.

Tony

[Bill PhinnParticipant @billphinn90025]

There is a 100mm-long twenty-pair set floating around out there. Arceurotrade and Amadeal among others sell, or at least sold, them. They may not necessarily be of the same quality at different suppliers.

They were the only set I used for a while, and often I obtained the height I wanted by doubling up parallels. As long as you seat the parallels and work carefully, I can't see any reason why placing parallels on top of one another to obtain a target height should be regarded as bad practice. One good feature of the set is the variation in thickness – something that, inexplicably, isn't very common with sets of parallels.

The spec. of the 20 pair set is as follows:

2mm width (5, 10, 15 & 20mm height)

3mm width (6, 11, 16 & 21mm height)

4mm width (7, 12, 17 & 22mm height)

5mm width ( 8, 13, 18 & 23mm height)

6mm width (9, 14, 19 & 24mm height)

[John HaineParticipant @johnhaine32865]

Absolutely no reason why their length has to match the jaw. Thinner ones are better, up (down that is!) to a point, as you can clamp thinner work. A tip, put a single parallel diagonally across the vice opening, put the work on top of it and carefully clamp – will work fine in most cases if the work is thinner than two parallels but thicker than 1.

I think Harold Hall explains how to make them in his book (maybe on website?), clamp steel strip to angle plate in pairs, resting on an improvised parallel, with the top of the strips above the top edge of the plate. Mill the two edges flat as one; then turn over end for end to mill the other edges. This must make them parallel, even if the one they are resting on isn't.

[not done it yetParticipant @notdoneityet]

Posted by Tony Pratt 1 on 14/12/2021 12:40:53:

3D printing is not the way to go, I can't think of anything less suitable for parallels than plastic.

Tony

Ooh, I don’t know about that. Certainly not the usual ‘starter’ plastic but there are some ‘reinforced’ filament materials available these days. As usual, the precision needs to be less than that which the part(s) is (are) being made to and certainly not less than that which would allow repeat parts in spec.

I have a set ex-Arc, but any in the future will be home-made, heat treatment/finish dependent on how long I would expect them to last.

[stuart jones 2Participant @stuartjones2]

If you 3d print with pla they will melt if you get them worm

[JourneymanParticipant @journeyman]

Well someone on Thingiverse got there before me *** LINK ***

John

[JasonBModerator @jasonb]

Another very good tip I saw in ME that the MEW readers may have missed is to write down on the rack or box where you store your parallels the depth below the jaws that each pair give rather than just their height. This saves trying one or two pairs to get that particular part just where you want it, all you do is pick a parallel that gives a depth just less than the thickness of what's being held. Must get round to doing it myself

3D printed would be handy for specific angles or as said nesting jaws.

[DiogenesIIParticipant @diogenesii]

It's not hard to make parallels with parallel long edges that 'will do' for most work, using a method I think I absorbed from ?Harold Hall;

Cut some strips of gauge plate / ground flat stock close to finished size and 'true' one long edge of each.

A couple of discs of scrap steel are bolted to a small angle plate with washers behind to hold them off the face, and the top of the discs skimmed, bringing them parallel to the table.

Without disturbing the set-up, the 'true' edges of your proto-parallels are placed across the freshly-cut tops of the discs, firmly seated and clamped, and the upper edge trued – with a little care, the end result will be as close to parallel as your machine is able to achieve..

It's possible to find quite large lumps of GFS surprisingly cheaply, and with a bit of foresight and planning , it's a quick 'Saturday Mornng' job to knock out a few pairs of different heights..

It goes without saying that there's no point hardening them, they will warp – I view them as consumable, but a generous chamfer avoids 'high-spots' if I drop or hit them and they seem hard wearing enough as is..

[not done it yetParticipant @notdoneityet]

It goes without saying that there's no point hardening them, they will warp

Agreed, but need not be a problem (and advantageous) if they are machined to final dimensions after hardening and tempering.

[BazParticipant @baz89810]

Posted by Bill Phinn on 14/12/2021 13:10:41:

There is a 100mm-long twenty-pair set floating around out there. Arceurotrade and Amadeal among others sell, or at least sold, them. They may not necessarily be of the same quality at different suppliers.

They were the only set I used for a while, and often I obtained the height I wanted by doubling up parallels. As long as you seat the parallels and work carefully, I can't see any reason why placing parallels on top of one another to obtain a target height should be regarded as bad practice. One good feature of the set is the variation in thickness – something that, inexplicably, isn't very common with sets of parallels.

The spec. of the 20 pair set is as follows:

2mm width (5, 10, 15 & 20mm height)

3mm width (6, 11, 16 & 21mm height)

4mm width (7, 12, 17 & 22mm height)

5mm width ( 8, 13, 18 & 23mm height)

6mm width (9, 14, 19 & 24mm height)

Warco are selling a set like this, see my earlier post, at about £75

[Bill PhinnParticipant @billphinn90025]

Sorry for overlooking your post, Baz.

DiogenesII, (you're a cynic?), could you say how you recommend clamping pieces of ground stock to the angle plate? I'm assuming they're like yours, i.e. without holes.

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