MadModder

The Shop => Tools => Topic started by: jcs0001 on February 12, 2017, 04:27:54 PM

Title: miniture dividers
Post by: jcs0001 on February 12, 2017, 04:27:54 PM
I bought these a few days ago at a local thrift shop.  They are small versions of dividers that I use fairly regularly.  A 6 in. (150 mm) scale has been included in the photo for reference.
(http://i1192.photobucket.com/albums/aa327/jcs0001/IMG_0008_6.jpg)

The large compass on the top right appears to be hand made - it is quite well made with no name on it.  It is a standard size.

The inside and outside dividers are Moore and Wright and the small straight divider is a Starrett.

The question I have is what were the small ones used for - model making or something similar?

Thanks,

John.
Title: Re: miniture dividers
Post by: awemawson on February 12, 2017, 04:40:03 PM
I have the identical twins of the Moore & Wright inside and outside calipers - been in my tool drawer near the lathe for at least 20 years  :bugeye:
Title: Re: miniture dividers
Post by: Chuck in E. TN on February 12, 2017, 06:23:14 PM
I don't have a clue as to their designated purpose in life, but I too, have the same small outside calipers. I set them to the target diameter when turning small bar stock on my lathe. For example, when threading and I need to make an undercut for threading tool to run out into. Mine were in the tool box I inherited from my late father, who was an industrial electrician/repairman.

Chuck
Title: Re: miniture dividers
Post by: Pete W. on February 13, 2017, 05:23:59 AM
That smallest pair of dividers is often stiffer than a larger set and so is better for marking out small features such as spaces or circles. 
Title: Re: miniture dividers
Post by: jcs0001 on February 13, 2017, 12:43:49 PM
Gentlemen, thanks for the replies.  They are quite nicely made and a real addition to my tools whether I use them or not.  For now they are beside my small taig lathe as it's likely they will be useful there.

Andrew - You've had them 20 years but have you ever used them??? :wave:

Chuck - that sounds like a good use.

Pete - makes sense to me.  Will try them out when needed.

The compass is very nicely made but the pencil holder was too large.  I made a brass spacer yesterday and epoxied it into place so that the pencil now fits very nicely. 

John.
Title: Re: miniture dividers
Post by: awemawson on February 13, 2017, 01:02:43 PM

Andrew - You've had them 20 years but have you ever used them??? :wave:


John.

Oh Yes - on those difficult bits where a 'digital vernier' won't fit. I love the 'quick release nuts' - very clever design.
Title: Re: miniture dividers
Post by: AdeV on February 13, 2017, 03:41:43 PM
'quick release nuts'

OK, now you've got me... how do they work? Both in practice & is there a design out there one could make?

I don't think I've got quick-release nuts on anything...

...well, except maybe [censored]  :lol:
Title: Re: miniture dividers
Post by: awemawson on February 13, 2017, 04:17:22 PM
Basically it's a nut that is tapered on the outer surface, and split along the axis of the thread into two halves. These fit into a female tapered 'outer' that grips them together so they thread to tighten. However when loosening the two halves relax and you can slip the nut along without turning it. If you take the pressure off the nut by compressing the limbs of the caliper the same happens. Makes adjustment over long distance very rapid.
Title: Re: miniture dividers
Post by: jcs0001 on February 14, 2017, 05:20:58 PM
Interesting about the quick release nuts.  My larger set of dividers has them but none of the three small ones appear to have such a thing.  Maybe I got the "budget" set.

John.