Thread wire measurement consistency

I despise using 3 wires: even in very experienced hands, it is easy to get wrong readings. I *much* prefer using a thread micrometer. I get bang on results, every time.
 
SLK001 said:
Unless you are measuring in exactly in the same place each time, expect variations.
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That's why I made the fixture. Now it is exactly the same place, to within a thousandth. DRO's are nice. My manual measurements were not consistent, thanks to the fixture, they are.

I don't care what the measurement is, but I care a lot that it is the same. That was the point of the original post. Fixed my problem.
 
Dabbler said:
I despise using 3 wires: even in very experienced hands, it is easy to get wrong readings. I *much* prefer using a thread micrometer. I get bang on results, every time.
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Someday I'll get them. For now, my MacGyver fixture will have to do.
 
I don't understand why use 3 wires instead of just one?
Once again Joe Pie to the rescue!
 
mikey said:
Are you using quality thread wires or imports? Pee Dee is a good brand and the wire diameter is typically consistent.

One thing that I recall helping, back in the olden days before I discovered thread micrometers, is that using the friction or ratchet mechanism causes inconsistencies in the readings. I found that ensuring the faces of the spindle and anvil were in good contact and then taking my reading without tightening further (without engaging the friction or ratchet) was the most consistent. I took hundreds of readings like this so I know it works. You might try it.

Then, when you get sick of manipulating things and doing calculations and searching for your wires in the chip pan, buy a good thread mic and be done with it. They are direct reading so no calculations, nothing to drop and you get to keep more of the hair on your head.
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Mikey and other posters are right; go with PD, B & S, any good brand. Cheap wires are soft, deform and bend easily in addition to being inaccurate.
Three wire measurement is a bit easier using two rubber bands over the three. One on each side to hold the wires, freeing your fingers up to work the mic.
Hope that's clear.
 
Bone Head said:
Mikey and other posters are right; go with PD, B & S, any good brand. Cheap wires are soft, deform and bend easily in addition to being inaccurate.
Three wire measurement is a bit easier using two rubber bands over the three. One on each side to hold the wires, freeing your fingers up to work the mic.
Hope that's clear.
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That's a good idea, especially with the thicker wires. Frees up a hand, and should make it a lot easier. Really felt like a three ring circus trying to manage everything.

I'll look for some better wires as well.
 
aliva said:
Check Stan's method of using 3 wires.
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Things are a lot easier that way, on a bench, with wire holders, than on a lathe! The idea is: Use a fixture or two to reduce some degrees of freedom, so one can concentrate on the measurement. Message received!
 
aliva said:
Check Stan's method of using 3 wires.
Click to expand...

Of course it's simpler to do on a bench. The main reason for doing it on a lathe is to not lose your alignment, so that if you're too big on the PD, you just take another cut. If you take your work off the lathe, you've lost your alignment/reference and have to pick it back up again once you are done measuring. Getting the work back in position is not the easiest thing and once you've also lost your reference, so you'll have to take a "referencing" cut to restart your threading.
 
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