Harig 612 spindle jamming. - Practical Machinist - Largest Manufacturing Technology Forum on the Web

Keith Doherty · #1 (**permalink**) 11-08-2009, 12:03 PM

I live in the UK. I have recently bought a 612 which is not in the best of health. It was built in 1980 and has obviously seen better days. The problem is that I can't get the spindle out.
The motor is off (I am afraid I didn't mark the alignment) and the spindle starts to slide out, backwards, nice and smoothly but it stops with a nice metallic clonk when it has travelled about 3 1/2 inches. As far as I am concerned this is impossible as there does not seem to be anything that could possibly get in the way. My machine has a square block spindle housing and the four grub screws which lock the spindle go in diagonally from the bottom edges - I have removed these. There is no sign of anything that could cause this obstruction.

The reason I need to get the spindle out is that the dust guards have been abused somewhat and are jamming. I need to take them off to straighten them out. It is also a good opportunity to give it a good clean.

Keith Doherty

RJT · #2 (**permalink**) 11-08-2009, 06:28 PM

Make sure there are no inserts left in the set screw holes. Sometimes a soft insert is put in ahead of the set screw to prevent damage and can catch on anything when you try to remove it. RJT

Keith Doherty · #3 (**permalink**) 11-09-2009, 04:06 AM

Thank you RJT. We (my toolmaker friend and me) had noticed that there are inserts in three of the holes but the holes go upwards so gravity would have to work backwards.

Also it seemed to me (by eye) that the holes had gone past the recess in the housing but I think I'm wrong. Keith.

So now the problem is how do you extract the inserts?

RJT · #4 (**permalink**) 11-11-2009, 01:43 PM

small telescoping magnet (if they are magnetic), dental tool with a hook, or tiny crochet needles, long tweezers, all things I have used in the past. Make sure it isn't a second set screw threaded into the housing . Good luck. RJT

Keith Doherty · #5 (**permalink**) 11-16-2009, 10:59 AM

Thanks again RJT. I took the bull by the horns and tried drilling on the basis that the insert might be brass and that if I drilled carefully it would not damage the spindle or the thread. The first (small) drill showed brass and the last drill did the trick, with a little bit of "persuasion" by pulling harder on the spindle. I reckon I am good at taking things apart but this one was a killer. Keith.