Making Parallels

I have loads of parallels in pairs, and they are essential for use with a mill, but have never used any with a lathe. 

The only way I can think of making any requires the use of a surface grinder, if you haven't got one just buy them ready made, new, or used.

Edited By old mart on 20/06/2020 15:17:52

Never ever needed to load a short, large diameter work-piece with clearance from the chuck face or to just protrude from the jaws? Easy with a couple of parallels.

Harold Halls book "Milling a complete course" has a chapter on making your own parallels. Seems to work quite well.

Peter

What a coincidence, This afternoon I started making my first pair following HH's book, then come in and see this thread for the first time.

Adrian

Axminster sell 95mm parallels and Proxxon 100mm parallels.

Sherline set 7506 2 1/2" long parallels.

Martin C

Sherline item added

Edited By Martin Connelly on 20/06/2020 17:33:48

The approach by Tom Walshaw [Tubal , Cain, often wondered where he got that name from, or why ] seems like a real down-to- earth way. Good to see that someone else uses the hammer to solve problems !

There was a tip in MEW a bit back about using the hardened stainless steel calibrated slide of a digital caliper or machine table readout. These are indeed very accurately ground and can be cut to length using a parting disc on a small angle grinder. When your caliper packs up recycle it as a set of parallels.

According to Wikipedia Genesis 4:22 says that Tubal-cain was the "forger of all instruments of bronze and iron" . As a result it's been used by a number of people which then causes some confusion.

Martin C

Tubal Cain was also described as 'The first artificer in metals'

In an old copy of ME LBSC had an enquiry from somebody who used the pseudonym Tubal Caine

He really took the mickey out of him by starting every paragraph with something like "Tubal Cain (with the 'E'……..)"

It really was very impolite of him!

Edited By Nick Clarke 3 to get rid of those damn smileys

Edited By Nick Clarke 3 on 20/06/2020 18:12:31

Andrew, I would use bar stock for your parallels, they will be good enough for most purposes, and if you accidentally drill or mill into them, you will not damage your cutting tools. You can buy enough material for a couple of sets of any size, and offcuts never go amiss. Mark them up when you get them so you always use a pair from the same original stock. You can get a lot of bar stock parallels for the price of the hardened and ground sets.

Chris Gunn

Make your own. Preferably with thinner stock than Harold Hall suggests. I made some of his, (I think from 8mm thick bms).

Very useful on the mill, but have had several occasions when I could do with thinner ones.

A version of his spring loaded one is very useful in the drill press, using one of his upgraded cheapo vices to near toolmaker standards.

Mike

OK I'm convinced. I'll do some shopping with Metals4You (??) or a better alternative?

Very impolite indeed, being that the Old Testament would have been originally written in Hebrew or Aramaic or some such Middle Eastern language with it's own script, then translated into Greek, with its own script, then into Latin before being finally translated to English a millennium and a half later, when spelling was largely arbitrarily assigned by each writer. So neither Cain nor Caine is any kind of original spelling of the name or even close to it.

Just goes to show that supercilious dilettantism was around long before internet forums made it accessible to the masses.

Key steel from bearing or engineering supply shops etc works very well. It is made to closer tolerances than most plain mild steel sections. I don't think it's ground finish, but certainly measures up as very parallel with normal mike etc.

I've had to make a few parallels myself recently. In three cases "make" meant modifying parallels I'd bought but discovered that their edges were far from being 90 degrees to their sides. In the case of one 2mm thick parallel, one of its edges was about 20 degrees off from 90.

All of the pairs in question were certainly matched pairs for height, but the sloping edges meant they either fell over in the vice when setting up a job or buckled inwards when work was being tapped down.

Has anyone else noticed this sloping standing/supporting edge problem with sets they've bought?

I have half a dozen pairs of HSS tool blanks which I use as parallels when required. I don't know how accurate they are, other than that my measuring kit shows the individual pairs as identical.

Hey there. We at ME ain’t no masses.

But we do know that all biblical characters were white skinned and spoke in English. 😉

Hey there. We at ME ain’t no masses.

But we do know that all biblical characters were white skinned and spoke in English. 😉

I was given a large piece of 1/8 thick gauge plate,thin parallels are useful when setting small thin pieces of work up in the vice,I still work imperial, so if you have say piece of 1/4 square material and want to remove say 1/32 then what is required is a narrow parallel but with height 3/16 below the top of the jaws,so I made a series or pairs of narrow parallels where the height below the jaws was more important than width this allows me when dealing with standard stock to be able to set up this material with a good grip on the work with enough protruding above the jaws to allow machining,very useful fo machining parallel keys and similar work, A toolmaker friend used to use aluminium bar for parallels to save damaging small cutters,he just fly cut them in pairs,just make sure the vertical head is trammed truly vertical. Hardened and ground Industrial parallels were used as they maintain accurracy over years of use and withstand lots of beating down of jobs onto the parallels with a lead hammer,nothing wrong in using soft parallels.

I have a selection of parallels which I have collected over the years. Although most of them are hardened and ground they are wide ranging from .75mm thick to 2 inch and some are buttons which are very usefull. I also hsve a set of adjustable parallels from Starrett which I bought when I was a bit younger and still use regularly to measure slots and use as parallels as well. The round button parallels are very usefull as you can bolt through them as well as spread them about to suit castings etc.

David