Help! > Mistakes, muckups, and dangerous behaviour

An anxious afternoon

<< < (2/3) > >>

simplyloco:
Good job you are OK, you are not alone!
I was a youngster setting up a 1" end miil in a large universal vertical milling head,  and didn't realise I was at the wrong end of the cut. When I started the cut the cutter caught, dug in, and such was the force applied that it rotated the milling head out of the cutting path and I was showered with shards of HSS from the shattered cutter!!
Good job I was wearing safety glasses, but I was picking bits of HSS out of my forehead for days afterwards...

vtsteam:
I once mentioned using a hole saw to Lester, my old time machine shop owner friend, and he said "I'll never use one in my mill again." I asked why, and he said he'd broken his spindle using a hole saw on a Bridgeport clone. He said he'd forgotten to lock the table. A replacement spindle had been very difficult to find.

Charles Lamont:
The mill is reassembled and running. The tight spot and nasty noise have gone. Indeed it is perhaps running a bit quieter than before. A DTI in the taper bore shows 0.0001" movement, at least some of which seems to be due to vibration from the belt drives. It is a relief to confirm no permanent damage done.

However, the bottom end of the quill is getting warm quite quickly with a few minutes running at moderately high speed. I don't think I have the bearings too tight as the top end is not affected. Perhaps I should not have grease packed the labyrinth seal at the bottom of the spindle. Grease is being pushed out round the spindle nose. 

Admiral_dk:
First congratulations to you solving the main problem - that must be quite a relieve, to have it back running, with a very small runout and normal noises  :cheers:

All Bearings have a table from the Manufactor where you can see maximum speed (RPM) and this is always very dependent on the kind of lubrication. Here Oil-Mist allows the highest RPM, Oil the medium and Grease the lowest RPM - all related to 'Displacement of Lubrication during Rotation' ...!
So having a Bearing tightly packed with Grease will be a problem over a not particularly high RPM in many cases ....

I would have a look on one of those Manufactors who make a Bearing of the same size (or better same model) as is in the Mill and look at the Table - but the fact that Grease is already being pushed out, suggests (as you wonder) that there is way too much Grease in there now.

Optimum would be a service manual for the Old Girl .... but that is probably not likely ....

Per

steamer:
It's happened to all of us at least once.    As long as your not hurt....the rest is fixable.

Dave

Navigation

[0] Message Index

[#] Next page

[*] Previous page