Tapered Pin Removal

[StudioMachinist]

Breaking down my brand new 727V to facilitate getting it into my basement and was unable to remove the tapered pins (part #Z5822) holding the left side X axis leadscrew support flange onto the table.

I made a very very crude slide hammer that didn't work and my only other idea is to make a plate with holes to run bolts into the tapered pins and then 2 threaded holes for jacking bolts.

Fortunately I got the machine down there without having to remove the table and when it's cleaned up and reassembled I might make the jacking bolt part.

Anyone else run into this problem?

 

[benmychree]

You generally have only one chance to remove well seated taper pins, it consists of one really good whack with a hammer and substantial drift punch; tapping away with a small hammer just serves to peen the end over making it harder to remove, short of drilling it out, which frequently goes off center and requires reaming the hole out to fit a larger pin; been there, done that ---

 

[StudioMachinist]

You generally have only one chance to remove well seated taper pins, it consists of one really good whack with a hammer and substantial drift punch; tapping away with a small hammer just serves to peen the end over making it harder to remove, short of drilling it out, which frequently goes off center and requires reaming the hole out to fit a larger pin; been there, done that ---

I understand that in the case of a pin in a through hole, but this is a blind hole. The pin isn't a roll pen but basically a small piece of round stock with female threads on the outside.

 

[benmychree]

I understand that in the case of a pin in a through hole, but this is a blind hole. The pin isn't a roll pen but basically a small piece of round stock with female threads on the outside.

The only way to remove that kind is with a puller of some kind, either a backhammer puller or simply a screw, sleeve and a nut to back it out.

 

[Asm109]

I'm sorry but female threads on the outside is a non sequitur.

 

[benmychree]

I'm sorry but female threads on the outside is a non sequitur.

I have seen them both ways, if the threads are on the OD, all one needs to remove the pin is a nut and a stack of washers (and a wrench).

 

[StudioMachinist]

I have seen them both ways, if the threads are on the OD, all one needs to remove the pin is a nut and a stack of washers (and a wrench).

Perfect! I'll give it a shot.

 

[Nutfarmer]

Are you sure it is a pressed in pin and not a stud?

 

[StudioMachinist]

Are you sure it is a pressed in pin and not a stud?

It's a pressed in pin in a blind. Appears to be 2 on each axis leadscrew support flange. I also have these same pins on the column of my LMS micro mill.

Thanks to benmychree, I was able to remove one of them with the washer trick, the other is still putting up a fight. I'm going to return to the problem when the machine is in its final resting place (I'm building a bench) and I can use it to make some kind of jack plate.