Starrett Divider

[thiggy]

I am curious about how this divider was used, and it's function.  The flat plate on the side with the large adjusting wheel does not move independent of the main leg of the divider.  As you can see, the one on the opposite side does swing up separately from the back leg.  The patent date is May 21, 1895.  Do any of you machinists out there know what this was called and how it would be used?  Thanks

[Bill Houghton]

Never seen a divider like that.  Inside and outside calipers of that design are used when you need to measure, say, inside a hole that's got a shoulder at the top of a smaller diameter than the location you need to measure.  Set your caliper, loosen the secondary nut, swing the "loose" leg aside, then reset it out where you can measure the setting.

I'm puzzled as to why you would never need to do that with a divider.

[wrenchguy]

sailors used dividers 4 navigating with charts.  others would use it 4 layout work.

[Billman49]

Never seen a divider like that.  Inside and outside calipers of that design are used when you need to measure, say, inside a hole that's got a shoulder at the top of a smaller diameter than the location you need to measure.  Set your caliper, loosen the secondary nut, swing the "loose" leg aside, then reset it out where you can measure the setting.

I'm puzzled as to why you would never need to do that with a divider.

Maybe an old pair of inside calipers turned into a pair of divider - I am also puzzled (as above)..

Navigation dividers are usually brass/bronze to resist salt water corrosion (with steel points) and often with a curved section to the legs, allowing one handed adjustment...

[wvtools]

It is called a transfer joint caliper.  You can make a measurement, fix the short leg, loosen the long leg, move the calipers away from the work piece, then go to another part of the work piece and check to see if it is the same size.  Or you can use it when you are trying to duplicate a part that you have.

[thiggy]

Thanks for the tool name wvtools.  After getting the name, I googled it.  I don't see any dividers of that type, only inside and outside calipers.  Is it likely that an outside caliper was reground to divider points? 

[mikeswrenches]

thiggy, if you go to the DATAMP web site and enter the pat. Date it will bring up your tool.  Follow the link under the picture to go to google patents.  Yours do not appear to follow the patent.

 I have a pair also, but they are calipers rather than dividers and they are made like the patent drawing shows. The fine adjustment makes sense on any of the tools, i.e. calipers and dividers, but having. the leg come loose on dividers makes no sense at all.  Having it come loose on inside calipers makes a whole lot of sense.

Are you sure they haven't been modified?

Mike

[wvtools]

I would also guess they have been reground.  They came in standard sizes.  I can check my old Starrett catalogs.  How long are they?  Measure from the center of the joint to the tip of the legs.

[international3414]

[thiggy]

Total length is 10 3/8".  Upon close examination, I think that the points have been reground to form a divider rather than inside caliper.  Thanks to all for your comments which helped clarify this curiosity.  I may let it go next garage sale.