> Hi All, > > In cleaning a dirty trackball mechanism in a duo 230, I managed to > separate the tiny plastic "wheels" from the thin wire "axle" they > turn on. It happened without great pressure being applied, to both of > the rollers in the trackball housing. Both plastic "wheels" appear to > have splits in them, and rattle about inside the housing.
I have had the trackball mechanism completely apart and have discovered that the wheels are rubber (or seem to be) and they simply slide onto the shafts. If yours seem like plastic and are split my guess is that it is old, hard rubber. Anyway, I had considered how one might replace them if need be. What I would try to find would be some very small rubber tubing. I have some small tubing but not quite small enough. Anyway, if you had a small piece of tubing you could cut a 1 mm length off the end of the tube. Slide it onto the shaft. Now put a small rubber O-ring over your short tube, to become the new wheel. If you cannot find a piece of rubber tubing small enough, you may be able to build up the diameter of the shaft by putting one or more "layers" of heat shrink tubing over it. The idea is simply to build up the shaft with available materials until you have a rubber wheel of the approximate correct diameter. An O-ring as the final "layer" should give a surface quite similar to the original rubber wheel. UPDATE! I just looked through my box of O-rings and the smallest one looks to be very close to the correct outside diameter of the trackball wheel. Its inside diameter is small enough that it appears I could use 2 or 3 short sections of heat shrink tubing to build up the shaft to accommodate it. If done carefully, I think the heat shrink tubing, when heated, will naturally create a little "rim" of sorts on its ends, to keep the O-ring from ever slipping off the ends. You might be able to manufacture the little wheel on a small shaft from your junk box etc. Then slide it off your shaft and onto the trackball shaft. This way you could experiment with procedures without running the risk of damaging the slotted disk which is permanently attached to the actual trackball mechanisms wheel shaft. I read somewhere of a guy who made a replacement wheel from a slice of a pencil eraser. He poked a hole in the center of the slice somehow. But to install it he cut the slice along its radius then slipped it over the shaft (instead of sliding onto the end of the shaft) then glued the slit. This is an interesting idea but I don't know how one would put a hole in the center of the 'eraser slice' that would be 'true'. The entire mechanism comes apart such that you can slide something onto the end of the shaft. It takes a delicate touch to deal with the little 'hair-like' springs, but I can do it so I know most people could, as I am not very steady, am somewhat clutsy, all thumbs etc. I compensate for these attributes by being slow and cautious. Greg ---------- Duo/2400 List, The friendliest place on the Net! A listserv for users and fans of Mac subportables. FAQ at <http://www.themacintoshguy.com/lists/DuoListFAQ.shtml> Be sure to visit Mac2400! <http://www.sineware.com/mac2400> To unsubscribe, E-mail to: <[EMAIL PROTECTED]> To switch to the DIGEST mode, E-mail to <[EMAIL PROTECTED]> Need help from a real person? Try. <[EMAIL PROTECTED]> ---------- Dr. Bott | 10/100 Ethernet for your 2400 is finally here! MPC-100 | <http://www.drbott.com/prod/mpc100.html> NineWire | If they are cool enough to host this list... Digital Solutions | ...you should check them out! http://www.NineWire.com/ Midwest Mac Parts ][ <http://www.midwestmac.com> After-market parts for Macs. ][ 888-356-1104 ][ MacResQ Specials: LaCie SCSI CDR From $99! PowerBook 3400/200 Only $879! Norton AntiVirus 6 Only $19! We Stock PARTS! <http://www.macresq.com>
