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How do I free up a micrometer carriage stop?

Lucaselef

Aluminum
Joined
Mar 19, 2015
I've got a micrometer carriage stop for a Heavy 10 that is stuck. I couldn't move the adjusting wheel at all so I started taking it apart. Ive got it apart except for the bronze bushings, main shaft and adjusting wheel, but even after soaking in purple power and pb blaster I can't get it free. I'm wondering if the carriage was crashed into it at some point. Any tips for how I can disable and check it out?
 
You most likely have corrosion between shaft and bushings. I've had atleast one stuck that way. Once fully a part you can clean it out nice and it will work nice.

One funny thing though, I pretty much never use the micrometer portion. I simply unlock the whole assembly from bed and move to where I want and lock it down. Which is probably why the get stuck, :D. Years of coolant or humidity working to lock it up.

If its like mine, you need to fully remove dial lock screw. Then dial just pulls off. Dial has a key or pin that spins shaft. The shaft is threaded in main housing.
 
That's the problem. I can't get it apart to clean it. The shaft and dial adjuster are seized together. If I install the key between the shaft and housing then I can't move the adjuster even the tiniest bit. If I remove the key then the shaft and adjuster just spin together as one unit. Anyone have any pics of one apart so I can try and understand what's going on inside?
 
The barrel is just threaded in the center something like 9/16” 20tpi. The ends are turned down to 7/16” if I remember correctly. One end has the key slot to keep the center barrel from turning. The number dial threads off the shaft and the shaft pulls out one side then the number dial drops out. It’s pretty simple but works when not frozen.

If the dial turns with the key removed then the the locking shoe under the thumbscrew isn’t frozen in place. I don’t think a crash by the carriage would have enough force to make the threads jam that tight. Dropping it might though. Check the ends of the barrel and collar for damage from a drop to concrete. If there are no signs of damage then probably corrosion. penetrating oil or maybe heat would free it. There are felt wipers on both ends of the casting, they probably won’t like the torch treatment if you go the heat route.

I have pictures of one apart somewhere, I will try to post them this weekend.

Hope this helps.

Ben
 
Ben, that helps a ton. I was thinking of ways to put a little more force on it without damaging the knurl, but wanted to make sure I wasn't missing something first. I'll soak it tonight and maybe try heat tomorrow. Thanks!
 
Make sure that the brass shoe isn't jammed in the locking hole.

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I stood it on end and soaked it in wd-40s version of pb blaster over night. Today I was able to get it to move and got the shaft pulled out. Thanks for the help everyone.
 
I don't believe that that is a South Bend stop. Unless it is a really old version, SB micrometer carriage stops looked like the pictures above from the mid-1930's on.

Most of the stop pictured is identical to my 1945 Heavy 10 - I assume they came together as it matches the pictures in the SB parts list that has the correct serial number entered as well. Lock screw is a replacement though, original is a knurled one, not what appears as the cap screw and nut in the above picture.

Mine was very tight - somewhat due to crud and old dried up oil. I eventually had to chase the threads to get it to work smoothly.

Dale
 








 
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