Wednesday, September 1, 2010

Motor replacement

The Hornby mech proved to be very noisy. I traced the source to a loose ringfield magnet. Unfortunately one of the plastic clips that hold it all together expired as I disassembled it. Rather than drill and tap a new fixing I decided to try one of my collection of CD loading motors I have saved over the years. It fitted to the Hornby case by use of 10BA bolts and some larger washers. The fitting of the Hornby motor gear to the 2mm CD shaft I found less than satisfactory after a couple of attempts to fill with solder and drill so I replaced it with a similar sized plastic one found fitted to another CD motor. It had 2 less teeth, so there will have been a dramatic reduction in the ratio (lessening any possible improvement in low speed smoothness). However the noise level is now satisfactory. These CD loading motors have the advantage of being very cheap (all mine were salvaged) but they are still only 3 pole straight cut motors designed for nothing more stringent than to run the CD table fully in and fully out so I didn't expect any miracles. The inside of one of these loading motors is shown above.

No comments:

Post a Comment