Replace roller rubber on HP 9825 tape drive

[Tony Duell]

> 
> 
> I'm trying to repair the tape drive in an HP 9825.  The roller has melted
> (no surprise there).  It seems like I could just get a bit of silicon

No suprise at all. All HP rollers do this in the end... I've got a 9845B 
on the bench at the moment, and both internal tape drives need new rollers.

> tubing or something that has the same diameter and guage as the existing
> roller.

Indeed you can. 

The other solution is to use an O-ring, put into a groove on the metal 
hub. IIRC, the 9825 tape drive (same mechanism as in the 9815, 9831, 
9835, 9845, 9877, etc) has a somewhat complicated hub, carrying the 
tachometer disk at the lower end, so it's not going to be easy to either 
make a replacement or machine the groove in the existing hub..

 
> I know this has been discussed before but I can't find any specific
> messages (by the way, the CC archive search is broken, Jay).  Can anyone

Another place to look is on the MoHPC forum (http://www.hpmuseum.org/, 
and follow the obvious links, or do a google search with 
site:www.hpmuseum.org). This problem has certainly been discussed there.

> provide any tips or guidance so I don't have to re-learn mistakes already
> made?
> 
> Any tips for cleaning off the existing material?  Isopropyl alcohol?  Any

Yes. That generally shifts it.

> thoughts of using heatshrink tubing and applying multiple layers until it
> has the same thickness as the original roller?

That has certainly been done. Either by someone here, or by someone on MoHPC.

> 
> Thanks for any help.  This will be a candidate for adding to the knowledge
> base once I've successfully replaced the roller.

Would you be interested in the instructions for doing this (properly!) on 
a 9810/9820 magnetic card reader? If so, I'll post/e-mail them to you.

-tony