my 2-3 starrett was dropped, and the shaft on the head was bent so I'm having to use a loaner browne and sharpe until I get my starrett fixed.
The only problem is that I can't figure out how in the world to adjust it.
It's about .0015" off, and it's not like the regular mics you see with the little key that you use to turn the base with. This one has no way to turn the base. to match up the zero with the head. It looks exactly like my starrett, but without the little adjuster hole.
Anyone know how to adjust this badboy? Am I just going to have to keep a mental note that everything is .0015" larger than measured?
adjusting old browne & sharpe micrometer
Moderator: Team
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Ed-vancedEngines
Can you post a pic of that mic?
All of my Browne & Sharps calibrate similar to the way a Starrett calibrates with a tiny Spanner Wrench.
I have senn a few mics years ago that you had to fully remove the thimble with the shaft attached and see if there is a nut inside of if the thimble body removes and a shim is inder it. I am just guessing. Possibly a pic could help for us to see which Browne & Sharp you have.
Ed
All of my Browne & Sharps calibrate similar to the way a Starrett calibrates with a tiny Spanner Wrench.
I have senn a few mics years ago that you had to fully remove the thimble with the shaft attached and see if there is a nut inside of if the thimble body removes and a shim is inder it. I am just guessing. Possibly a pic could help for us to see which Browne & Sharp you have.
Ed
it came with the little wrench, but it also came with this wierd looking piece that is threaded in one end but does not match up to any of the threads on the mic. The top of the head has a hole for the little wrench, but it only unscrews the thumb ratchet top.
I removed the head on this one to clean it, and there are two little collars that screw on to the top of the shaft... but they don't do anything. I tried messing with them, but they had no bearing on where the mic would stop or anything at all. I'm stumped.
mic
On the old brown and sharps the sleeve ( the numbered part) is part of the main frame. The thimble is held in place on a taper to the spindle. If i rememebr right you need to back off that nut you were talking about and then you need to free the thimble from the taper... this can be a challange if it's never been moved in it's life and the mic was used around coolant...
BUT, before i even tired to adjust it i would check that mic at 2.5000" and 3.0000" and see if the same .0015" shows up...
A micrometer that is off .0015" is a big red flag to me...It would be like an engine that dropped 20 lbs of oil pressure... something is wrong ..usually.
Keith
BUT, before i even tired to adjust it i would check that mic at 2.5000" and 3.0000" and see if the same .0015" shows up...
A micrometer that is off .0015" is a big red flag to me...It would be like an engine that dropped 20 lbs of oil pressure... something is wrong ..usually.
Keith
“If I hit you with this you’re going to be numb, that’s why they call them numb-chucks “Si Robertson
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Ed-vancedEngines
I looked at a set of Brown & Shrap 2-3 that I have with friction thimbles but they have the little hole for the spanner wrench for adjusting the sleeve.
I did see in an old set of 2-3 Starrets what looked to be and I am pretty sure is an adjusting nut to adjust how deep or shallow the thimble can set into the sleeve. Remove your thimble completely with shaft attached by just backing it out until it is free and can be pulled out. Look inside the sleeve and I'll bet you will see a nut that can be adjusted. I think that is it, but am not positive. Adjust the nut to go in slightly more or out slightly more and that hopefully will also adjust whre the numbers on the thimble line up with the numbers on the sleeve.
Look for certain all around the sleeve for a tiny hole that is very near the micrometer frame. If none is there it must have to be internally adjusted.
Ed
I did see in an old set of 2-3 Starrets what looked to be and I am pretty sure is an adjusting nut to adjust how deep or shallow the thimble can set into the sleeve. Remove your thimble completely with shaft attached by just backing it out until it is free and can be pulled out. Look inside the sleeve and I'll bet you will see a nut that can be adjusted. I think that is it, but am not positive. Adjust the nut to go in slightly more or out slightly more and that hopefully will also adjust whre the numbers on the thimble line up with the numbers on the sleeve.
Look for certain all around the sleeve for a tiny hole that is very near the micrometer frame. If none is there it must have to be internally adjusted.
Ed
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Cobra
Any red lights go off after reading this statement? I borrowed a mic that is 0.0015" off. This is no problem if you are measuring 2X4s! An engine builder is only as good as his tools! Buy new, quality measuring tools, have them regularly certified by qualified persons, (in house or independent lab), keep them clean and undamaged. I am amazed at the number of engine shops using precision tools with no documentation. When I speak of certification this is not just setting a mic to a standard.