Starrett micrometer fix

Found this thread searching for pictures of the "Lock Ring" assembly for a Vintage Starrett No. 230 that I recently purchased on eBay. Upon receipt of the micrometer, the spindle was a little tight to turn and the lock ring was frozen in place. I put a little oil on the lock ring and it freed up and began to work. Time to give it a good cleaning and some oil. Without knowing better, I moved the lock on and off while I had the spindle out and the locking mechanism closed down tight and the spindle barely moved without considerable effort. After seeing the pictures of the parts that are in the lock ring assembly it was time to disassemble it and remedy the problem.

I suspect that what I found is the same for most vintage micrometers, years of old dried oil that looked like varnish, with plenty of dirt and grit...no wonder the lock ring assembly was frozen. What you don't see in the picture is the inner split ring, it has a slit in the sidewall making it very weak. When you apply the lock without the spindle it will collapse and it did. I used an exacto to open the gap, then verified that the spindle would fit without drag and the inner locking mechanism would still fit the outer ring. Cleaned, polished and oiled everything... it works like new.

Thanks for posting the pictures and the details, made this an easy fix.

Robert
 
There is a barrel spring for this mic. Was it present when you disassembled? You can order parts from Starrett if anything is worn.
 
The parts I found inside were the same as pictured above. What does the barrel spring look like? What does the spring do?

Thanks
 
The parts I found inside were the same as pictured above. What does the barrel spring look like? What does the spring do?

Thanks
According to the Starrett 3d parts viewer, there is a spring. SPRING, BARREL10058-01
You can call or email Starrett and they will provide parts, .pdf parts drawings and info.
The Starrett 3d viewer can be downloaded, installed and seems to work on MS Internet Explorer only. (doesn't work in Chrome).
This model has been updated and is n ow the T230XRL., using 19 parts instead of 20.

I don't know what the spring does. I don't own any Starrett micrometers. I only see it in the 3d parts viewer.
T230RL Parts:
Illustrated Parts Catalog
logo.png

Published Date: 2015-02-03

ITEM DESCRIPTION PART NO. QTY INFO

Illustrated Parts Catalog
logo.png

Published Date: 2015-02-03

ITEM DESCRIPTION PART NO. QTY INFO
Printed: 2017-12-28
boxnone.gif0OUTSIDE MICROMETER CALIPERT230RL boxshow.gif1FRAME SUB ASSEMBLYNOT AVAILABLE1 boxshow.gif2SHELL, OUTSIDE09990-01 boxshow.gif3NUT, .375-5216414-01 boxshow.gif4SPRING, BARREL10058-01 boxshow.gif5LOCK NUT , #230 ASSEMBLYPT990601 boxshow.gif6•RING, BINDER09209-01 boxshow.gif7•RING, FRICTION05324-01 boxshow.gif8•ROLL, BINDER05325-01 boxshow.gif9RATCHET ASSEMBLYPT198321 10•CAP ASSEMBLYPT994451 11••RATCHET13196-01 12••CAP, RATCHET07671-B1 13•BODY, RATCHET #23019773-01 14•PIN, RATCHET .066D X .156LPT189761 15•SPRING, .041X.061X.188X.010X6PT076731 16•SCREW, #2-64 SLOT X .204 LONGPT197721 boxshow.gif17WRENCH #3PT015261 boxshow.gif18SHELL, ADJUSTING08752-01 boxshow.gif19ANVIL07969-01 boxshow.gif20SPINDLE07585-0
 
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Thanks I have one to that's not right. I also own several Lufkin mics they have a very unique take up on the barrel threads it's like a back lash adjusters . If you take the barrel out past it don't just start tightening it back it'll jam up , you have to load the spring has you thread the barrel back in. Just trying to help not change or anything.
 
The parts I found inside were the same as pictured above. What does the barrel spring look like? What does the spring do?

Thanks

The spring is a slightly curved but flattish leaf spring that tensions the sleeve with the graduation scale against the micrometer frame.
It holds the sleeve in place but allows it be adjusted with the small wrench.

I did a picture with some screenshots from the parts viewer to try and make it clearer

Starrett-230XRL.png
 
HELP: I have a Starrett T230xrl (0-1") and the spindle/thimble will not move at all. It's been soaking in Kroil for a few days to no avail.
Otherwise it looks in perfect shape. If it could only take it apart.
 
HELP: I have a Starrett T230xrl (0-1") and the spindle/thimble will not move at all. It's been soaking in Kroil for a few days to no avail.
Otherwise it looks in perfect shape. If it could only take it apart.

I had the same problem with mine. I sent it to Precision Instrument Correction.

They fixed it and calibrated it.
 
Maybe try heating up a little in your oven try 200degrees shouldn't hurt anything at that temperature but may allow the kroil to creep in .
 
After a month in a hot garage, the thimble, sleeve, and ratchet came off. The spindle is still stuck. I don't see an area to torque with a pliers. The ratchet screw goes deep within the spindle. My garage when out to 120 degree and my wife would have a cow if it put it into the food oven.
 
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