Odd-leg calipers ??

[WisJim]

I was recently reading through the book "The Modern Machinist" by John Usher, ca 1895, and came across a "odd-leg calipers" which looks like a real interesting tool, but I can find no mention of a tool with this name that is the same configuration as the tool mentioned in the book. The currently available tools that show up when looking for an "odd-leg caliper" online is actually a hermaphrodite caliper, which is not the same thing as shown in the old book. I'm attaching a photo of a page from the book so you can see what the calipers are like and how they differ from what we see today.
So--my question is, does anyone have a source of this style of caliper? I'd like to find one to use as it looks like it can be useful in the shop. I was thinking that I could take apart a regular outside caliper and rework it and reassemble it in this configuration, but I'm not sure if that would work well or be practical to do.

 

[Brian Rupnow]

Could you not just buy a set of internal calipers then heat one side with a torch and bend it the other way?

 

[Sprocket]

Take out the pivot and flip one leg over.
Then it could be changed back.
Doug

 

[abby]

I have two or three pairs which I never use, you could have them but unfortunately the postage would probably cost more than they are worth.
Dan.

 

[WisJim]

Take out the pivot and flip one leg over.
Then it could be changed back.

That's what I was thinking of when I mentioned reworking common calipers.

 

[wazrus]

I have a couple of pairs of 'odd leg' calipers. They used to be known - and probably still are known - as Jenny calipers: "jennies".

 

[BaronJ]

Hi Guys,

About the only time I can recall using a pair of Jenny's is when line boring and using them to set the cutter in the boring bar !

 

[WisJim]

When I use Google to search for "odd leg caliper" or "jenny caliper" all the images and available tools are actually hermaphrodite calipers, which is NOT the same thing. However, the dictionary definition appears to be describing what I am looking for.

 

[ChazzC]

When I use Google to search for "odd leg caliper" or "jenny caliper" all the images and available tools are actually hermaphrodite calipers, which is NOT the same thing. However, the dictionary definition appears to be describing what I am looking for.

Searching both Blackgates & RDG Tools in the UK for "Odd Leg Calipers" yields Hermahrodite calipers, and Guy Lautard's mentions of Odd Leg Calipers in TMBR show Hermaphrodite as well.

Zoro has these, which should easily be transformed by simply rotating flipping one of the legs:

However, at $13.28 I doubt that you'll receive Moore & Wright from Sheffield, particularly since the Country of Origin is listed as "China."

eBay has a NOS listing for 4" M&W calipers for $28+/- (from Canada), and many others (search "firm joint inside calipers")

 

[Badhippie]

Hermahrodite calipers actually have just one leg bent inward and the other leg is straight used for marking edges and perimeters and such

 

[methuselah1]

I was recently reading through the book "The Modern Machinist" by John Usher, ca 1895, and came across a "odd-leg calipers" which looks like a real interesting tool, but I can find no mention of a tool with this name that is the same configuration as the tool mentioned in the book. The currently available tools that show up when looking for an "odd-leg caliper" online is actually a hermaphrodite caliper, which is not the same thing as shown in the old book. I'm attaching a photo of a page from the book so you can see what the calipers are like and how they differ from what we see today.
So--my question is, does anyone have a source of this style of caliper? I'd like to find one to use as it looks like it can be useful in the shop. I was thinking that I could take apart a regular outside caliper and rework it and reassemble it in this configuration, but I'm not sure if that would work well or be practical to do.

Hello there- I own a copy of that same book, and I have never seen such a caliper for sale. Firm joint calipers actually come in two flavours- cheap (rivetted) and decent, the latter type having a bolt at the joint. They are still inexpensive. They can be dismantled, then reassembled with one of the legs flipped over, to produce the caliper in the illustration.

We have a firm in the UK called Moore and Wright, who started in 1906 making Starrett instruments under licence. Their smallest current offering is the 6" model 3306, at £10.20, (that'll buy 20 cigarettes here) which you can see on a google image search. They can be readily bought in Australia for about the same cost! Starrett will inevitably have made the exact same tool in the past, but I cannot find a new price; I doubt there's any great demand; but Ebay can be a wonderful thing, and knowing the new price will prevent you from getting "tucked in".

That said, I spent my working life as an engineer, and I never had a job that required the configuration Usher describes. If you don't have firm joint calipers, treat yourself, but I'd wait and dismantle them come the day.

-Andrew UK

 

[wazrus]

Hi Guys,

About the only time I can recall using a pair of Jenny's is when line boring and using them to set the cutter in the boring bar !

 

[wazrus]

I used to use my Jennies quite a bit, especially when marking out, for lines parallel to an edge. Now I have two alternatives, one is a marking gauge not unlike the one used by woodworkers, but made from metal, the other is a vernier caliper equipped with a carbide scribing point. It may be argued that the scribing point on a vernier, due to wear, is a bit doubtful, but I've found the thing to be most useful. In fact, I now have three, as they are cheap as chips on the 'net. The carbide point 'zeros' to a roller on the moveable sleeve.

 

[holmes_ca]

I was recently reading through the book "The Modern Machinist" by John Usher, ca 1895, and came across a "odd-leg calipers" which looks like a real interesting tool, but I can find no mention of a tool with this name that is the same configuration as the tool mentioned in the book. The currently available tools that show up when looking for an "odd-leg caliper" online is actually a hermaphrodite caliper, which is not the same thing as shown in the old book. I'm attaching a photo of a page from the book so you can see what the calipers are like and how they differ from what we see today.
So--my question is, does anyone have a source of this style of caliper? I'd like to find one to use as it looks like it can be useful in the shop. I was thinking that I could take apart a regular outside caliper and rework it and reassemble it in this configuration, but I'm not sure if that would work well or be practical to do.

Could they be what I know them as, "Jenny Calipers" do a search

 

[Mike Ginn]

Interesting! In my 50 years of model making I have never used Jennies/odd leg calipers. I could use the vernier caliper for marking as per Blondihacks but guess what - I have never done that either. I think we all get used to ways of working and my methodology doesn't seem to include Jennies!

 

[ChazzC]

@WisJim
Continuing my search on eBay I found several listings by different Sellers (but all located in the same city & state?) for 5-packs of M&W 3306 calipers (with a Made in UK label on the box) at steeply discounted prices. I watched the cheapest one and sure enough received a discount offer overnight: 5-pack for $20 & free shipping. Tool Junkie that I am, I now have them coming my way. I'll post the results of my modification.


Charlie

 

[methuselah1]

@WisJim
Continuing my search on eBay I found several listings by different Sellers (but all located in the same city & state?) for 5-packs of M&W 3306 calipers (with a Made in UK label on the box) at steeply discounted prices. I watched the cheapest one and sure enough received a discount offer overnight: 5-pack for $20 & free shipping. Tool Junkie that I am, I now have them coming my way. I'll post the results of my modification.


Charlie

Should have been labelled "Sheffield England". That's where our steelmaking tradition really began.

 

[76dave]

The attached picture shows what I have always considered to be "Oddlegs". These came with a set of calipers, dividers etc, that I bought over 40 years ago. In all that time,I cannot recall ever using them.

 

[Badhippie]

That picture there from 76Dave them are hermaphrodite calipers. That’s what I have always been told and even seen them in catalogs

 

[WisJim]

The attached picture shows what I have always considered to be "Oddlegs". These came with a set of calipers, dividers etc, that I bought over 40 years ago. In all that time,I cannot recall ever using them.View attachment 142800

As I mentioned in my previous posts, these are NOT odd-leg calipers as defined by Webster's dictionary or as shown in the book that I mentioned at the beginning of this post. These are hermaphrodite calipers and they aren't what I am asking about.