Telescoping bore gauge disassembly (Lufkin)

[ckucia]

Have a set of Lufkin telescoping bore gauges. Came in a plastic pouch and I discovered I have some moisture issues in the garage. They have some light rust on them, luckily mostly on the handles. But they are old and the oil inside is a little gunky.

So I've been disassembling, lightly soaking in evaporust and then am cleaning them up - one at a time so I don't mix up or loose the little pieces.

However, within the pouch there appear to be two different designs. These were my father's or grandfather's (both deceased) so I can't ask the history.

Anyhow, on one type, the locking screw is threaded on the knurled end and the rod is smooth all the way up. On the other, it's threaded at the end of the rod that goes into the head. Both have (I'm guessing) a retaining pin that sits on top of the rod on the locking screw and goes into the head to lock the anvils.

So on the former, the locking pin is visible and I can just pull it out. On the other, the pin must be inside the head, so I can't seem to get it out to release the anvils. Tried a magnet without success and tried lightly tapping while releasing the tension on the pins while squeeing the anvils. I'm guessing the gunked up grease is keeping the pin from dropping out. I put the locking screw assembly back in the handle and it doesn't appear that it goes deep enough into the head to lock the anvils, which makes me think there's a little pin in there (that and the anvils won't come out).

Was wondering if there's a trick to getting that pin out. About the only idea I have is soaking the head in penetrating oil or some sort of solvent and hoping it releases eventually, but if I can't get it out, then I'm not sure I'll ever get out all that solvent or penetrating oil.

Any ideas?

 

[ckucia]

So a little more info and a pic.

The ones I can get apart are actually Starrett. Upper one in the photo.

The lower one (Lufkin) is where I've disassembled as far as I can, but there appears to be a little pin recessed in the head keeping the anvils in place.

 

[Kev Smith]

I know that your post is pretty old now, but I was wondering how you solved your problem and if you remember how you did?

My story is exactly the same as your story: Starrett and Lufkin... old and rusty... Evaporust... stuck anvils on Lufkin.

Any hints or suggestions?

Much obliged.
Kev

 

[ckucia]

Hi Kev,

Wish I could say I found a solution but I never did. I was able to get some shim stock cut to fit inside the recess and slide it over the pin. I tried shoving more shim stock above that to try to force the pin down and I could never get it down far enough. I tried penetrating oil without success. Didn't want to try Evaporust inside the head since that seems to have bad long-term effects on steel and I wasn't sure I could get it all out if I didn't get them apart.

Sorry I can't be more help. I just set mine aside for now the way they were hoping maybe I'd get back to them with fresh eyes and fresh ideas. Can't believe it's been like 9 months since.

 

[Kev Smith]

Thanks so much for the reply.
I'm going to keep at it and see if I can get the darn thing apart. I'll post something if I succeed.

All the best.
Kev

 

[ckucia]

Best of luck. Hopefully you'll succeed where I failed.

I searched the web using every set of terms I could think of and we seem to be the only two people to ever have this problem

 

[homerj]

My Lufkin bore gauges are slightly different (they have female threads and handle screws into the head. You're right about there being a pin inside that tube. You mentioned that the oil is gunked up. Maybe try soaking in mineral spirits? Or do you have a right angle dental pick? Come in from the side and try to get the tip of the pick between the pin and the keyway milled into the anvils? If you don't have a dental pick a whittled down tooth pick might do the trick.