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Lufkin 212 depth micrometer

pw777

Plastic
Joined
Sep 12, 2011
Location
Belgium
I recently obtained an old Lufkin depth micrometer no. 212, and I have some questions/problems with it:
  • the lock nut doesn't work. Is there any way to fix it? I don't see how I can dissassemble it
  • the adjustment wrench is missing. It's a friction wrench as you can see in the bottom right in the picture below (picture taken from Lufkin catalog no. 7). I can't find this part anywhere separately. Do you guys have any useful pointers?
  • How can I find out approximately how old this thing is? There is a piece of paper glued to the inside of the cover of the wooden box, mentioning "PATENTED AUG. 1ST, 1922 JAN. 5TH, 1926" so my first idea was that it dates maybe from the late 20's or early 30's but this micrometer must have been produced during a long period because it is listed in successice lufkin catalogs, from no. 7 (I don't have an earlier one) up to no. 9 (I don't have no. 10), and no longer in no. 11. There are no dates in the scans of these catalogs.
Thanks
Patrick
 

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Oh, but it does work, runs smooth, is accurate enough for me and returns to zero. So right now I don't really need the spanner. But besides being useful I like older tools to be complete, so if I can find the missing spanner cheaply, I would be happy. And the fact that the lock nut doesn't work doesn't bother me much. It's just that if there were a simple fix that I could carry out myself then I would go for it.
 
pw777 - several of our employees have Lufkin-brand micrometers in their toolboxes, and they appear to be well-made. Since I do the calibrating, I've found them to be right on the mark.

Nice find, and good luck with it. I don't think you'll be disappointed.
 
Something like spark plug pliers will be a good replacement for your missing wrench. The back cap usually comes off pretty easily to change rods.

I wouldn't worry about the broken lock. It's not of all that much use in a depth micrometer. If you do what to take a look, start disassembling the mic from the rear, including sliding off the sleeve. The 1926 patent is for your (broken) lock. You can probably go the the USPTO web site, download an image viewer, and get a diagram.

As for age, if yours is satin chromed it's fairly recent (say, late 40's to 60's when the company closed).
 
I found the patent and the drawings show how the lock nut works, but not how it is fitted to the micrometer. I'll see how easy the sleeve comes off, if it doesn't move I will leave it alone. I'll borrow a spark plug plier from my neighbour who repairs motorcycles. The back cap indeed comes off easily.

As for the age: it is not chrome plated so it must be older.

Thanks
Patrick
 
Several years ago as i was passing through Flint, MI on my way back to Canada from Kentucky, I had the opportunity to pick up an old Kennedy chest half filled with mostly junk. (it was the box I wanted...the junk was bonus)Not being the type to throw stuff out, I'm sure I still have all of it. Of the stuff that I had no clue as to it's use, was the little bugger pictured below. I too have a Lufkin depth gauge, but it's the 513F and it came with 2 wrenches that look nothing like that. PM me with your address and I'll send it to you.

Mike


Picture002a.jpg
 
This is a double tool.

The toothed part on the end is a regular spanner.

The curved portion is a tension wrench designed to fit around the barrel of a micrometer or similar.

- Leigh
 
That's indeed the part that I'm looking for. I've sent you a PM.
Thanks, Patrick

Several years ago as i was passing through Flint, MI on my way back to Canada from Kentucky, I had the opportunity to pick up an old Kennedy chest half filled with mostly junk. (it was the box I wanted...the junk was bonus)Not being the type to throw stuff out, I'm sure I still have all of it. Of the stuff that I had no clue as to it's use, was the little bugger pictured below. I too have a Lufkin depth gauge, but it's the 513F and it came with 2 wrenches that look nothing like that. PM me with your address and I'll send it to you.

Mike
 
More Lufkin depth micrometer questions.

This sounds like a "happy ending" story :) My favourite kind.

Hi all, I have a Lufkin 513 depth mic which I purchased second hand. It is complete with box, wrench and extension. It worked fine until it got , I suspect, wet. I dismantled it in order to clean off some surface rust, lubed it with WD40 and when I was happy it was dry I tried to re assemble it. The thimble will screw onto the sleeve about a quarter inch, until the scales meet at about the 1" mark but then it gets tighter and eventually, a couple of turns later it jambs. Someone told me that these need some downward pressure in order to engage the anti backlash device in the thimble. I cant feel it and certainly cant see it. I have downloaded the two patents quoted on the shoe but neither seem to relate to my thimble arrangement though the one does relate to the locking mechanism. Does anyone know how to open up the thimble to expose the internal threads that engage the sleeve? I suspect that the thimble comes apart where the "knurled" part meets the "scale" part but a fair level of force using two chucks as wrenches has so far not produces any result. Any ideas would be welcome. I know its not worth a lot but curiosity has me going now and I hate to be defeated by a "chunk of iron".
Twistit
 








 
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