A little expertise needed!

[Dixieblade57]

My son in law works for a company that does maintenance for several hospitals. He recently had to replace a drum on a electrocardiograph machine that rolls out the paper, the only thing wrong with it was it had lost its stickiness and therefore its ability to roll out the paper.
So he comes into the house the other day carrying it and says you got any use for this, (he knows I am a packrat)! The light bulb went on and I am thinking this will make great rollers for my platen for my KMG clone I am building.
This thing is very heavy. This makes me think it is probably a solid stainless steel drum with approx. a 1/8” rubber cover. It is probably 1 1/2" diameter and approx. 10" in length.

Pictures below
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OK here is my problem. How do I:

A. What (bit or bits) should I use to drill this because this is medical grade SS

B. How do I find dead center and keep it centered?
I am thinking maybe this needs to be done on a metal lathe to get it centered exactly!
Getting off center a little bit will lead to vibration, of the rollers.

Any thoughts on cutting this into sections and drilling center would be greatly appreciated. I know we have several machinists on the forum, maybe some of them have some ideas on what I have in mind!

 

[EZ Cad Blades]

Dixieblade57,
I'll weigh in. Seems like a reasonable enough idea. If it were mine I think I'd first try to figure out if it has been hardened. Probably not, but ... you never know just by looking, right? You can check it with a file for hardness. If the file cuts it pretty easily, no problem; you should have no trouble cutting it using a band saw. If, on the other hand, it is hardened the file will "skate" across the surface rather than cut it. Can still be worked, but only using carbide tooling which may be more costly than it's really worth. Your call on that one completely. If it is relatively soft and you cut it into pieces on a band saw, and the the next step would be, as you already surmised, to take it to the lathe. If you have access to one you could machine out pockets to receive a bearing in either end (I'd recommend a press fit). If it were my project I'd probably cut it in sections large enough to leave enough on each end to chuck up on in the lathe, then I'd indicate it to make certain it was running true before any machining. You'd need to clean off the rubber, obviously. Hope this helps.

BTW: Nice find! :thumbup:

Larry