Thin Parallels?

[Bo’sunParticipant @bosun58570]

I’ve failed to find any 1/16″ or 1.50mm thick parallels, but there seem to be several 1/32″ sets available.  So I thought I’d ask, “what are they like to use”?  Given that work pieces may well have chamfered corners.

My ARC 2mm “precision metric parallels” work just fine, but stacking them can be awkward, and something just a little thinner would be useful at times.

[JasonBModerator @jasonb]

Consider the wavy ones which squash right down.

[mark costello 1Participant @markcostello1]

Strap banding works well within it’s range.

[Neil LickfoldParticipant @neillickfold44316]

I have taken to just getting Ali extrusion that is 1.5mmthick or 1.6mm thick. In NZ can get from Mitre10 20×1.6mm flat bar in 1m lengths. And some other sizes. I just mill them to suite what I am doing at the time. If you drill into them, it’s no big deal. I use a lot of ali safety plates in my vice by the jaws. Especially when holding something and want to go to the side of the part. Just double sided tape to the steel jaws using 6mm thick extrusion.

I sometimes run a 3mm cutter down the the middle of the 2 ali pieces, leaves a 1.5mm edge parallel to the run of the mill table. Add a spacer at the bottom so the part is held parallel. Its like an easy 1 off soft jaw for the vice.

I use an old well used set of gauge blocks for the milling spacer, bought for this purpose. The good set is used like they should be.

Neil

[Clive FosterParticipant @clivefoster55965]

+1 for Jasons suggestion of wavy parallels. Even working at 12 inches to the foot scale mine are get regular use.

Never trusted the very thin solid parallels because they are so easy to bend if you are careless for a moment.

The wavy ones are designed to bend. Hafta accept that they won’t last for ever tho’.

Much to be said for Neils consumable parallel made in situ to suit the job.

Clive

[mark costello 1]

On mark costello 1 Said:

Strap banding works well within it’s range.

Good tip, I’ll have to remember that.

[DiogenesParticipant @diogenes]

In a similar way to Neil I sometimes use ali ‘soft jaws’ in the vice, tho I made a ‘flippable’ pair to screw on.

I think the ‘little’ side has steps something like 1 1/2mm square and the ‘big’ side is probably something like 2 1/2mm – I only skim them for ‘critical’ work and then sparingly, but they’ve done at least two years to get to the dims. above.

As with all ali. fixtures you do have to be careful about dings, knocks, embedded chips, etc., and inspect carefully before mounting work.

I only put them up when I need them, but wouldn’t be without them.

 

[David George 1Participant @davidgeorge1]

I have a set of small parallels which were made from gauge plate hardened and ground. They were made whilst at work in a toolroom but they were sent to a professional hardening company which means there was little distortion whilst being hardened and I had a surface grinder to finish them on. these are 0.032″ x 0.985″ x 3″    0.0625″ x 1.125″ x 3″   0.125″ x 0.375″ x 3″    0.187″ x 0.375″ x 3″

 

These are absolutely essential to me and especially the thin ones which I use  with a spring between them to hold them in place whilst loading as they tend to fall over otherwise. You can buy gauge plate which is ground already and doesn’t have to be hardened for the use that model engineers and as long as they are cut from the same piece of material will be more than adequate. I have a few parallels which are just gauge plate cut to size length wise and are just as useful you just have to check them for dings and dents with a fine stone occasionally as any swarf could damage them in use.

David

[Charles LamontParticipant @charleslamont71117]

Hadn’t thought of the spring. I think that’s worth the Tip-of-the-Month thread (even though I don’t use very thin parallels much).

[Bo’sunParticipant @bosun58570]

Thanks for the suggestions everyone.  I like David’s idea of using a spring, or springs, to support thin parallels, but I rarely seem to have any the right size, especially when the parallels are close together.  In such cases I use “closed cell” foam mat (cut from a sleeping mat) that can be easily trimmed to size.

[PeteParticipant @pete41194]

I just use a single drop of thin oil on the back side of each parallel. If your mill vise also has jaws in decently ground condition and there clean. 14-15 psi of positive air pressure holds the parallels in place and they never fall over even when the vise is opened or closed.

[John HinkleyParticipant @johnhinkley26699]

When I started this hobby some few years ago now, I bought cheap digital calipers to match my abilities. Inevitably, they didn’t last long and ended up in drawer.  After reading a “reader’s tip of the month” in MEW, I repurposed a couple of them by going at them with a Dremel and cutting disc, ending up with two thin parallels from each caliper of approximately 80mm x 20mm x 2mm, which served me well.  I could cope with the occasional “ding” by dint of carelessness as there was a ready supply of replacements waiting in the drawer.

John

 

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