Graupner Speed 600 Race modifications
22 Jan 04 - Added diagram of tag cutting position.
Timing Change For Reverse Rotation
If you want to use the Speed 600 Race motor with reversed rotation (e.g. for single stage gearbox or as a pusher) the timing needs to be reversed. The modification is actually quite simple and is as follows:
1. Release the springs holding the brushes and withdrawn the brushes.
2. Open the 2 tags that hold the backplate in position. This is much easier said than done as they are quire strong, but it can be done with a little patience. I slightly damaged the brush carriers on my 1st motor, but they were easily straightened & perfectly serviceable. This can be avoided by total removal of the brush carriers, but I haven't bothered with this so far.
3. Remove the backplate and armature from the motor and put them one side.
4. It is a good idea to back the motor with soft tissue to help stop the swarf from attaching to the magnets.
5. You will notice that the tags are cut about 6.5mm to one side of the middle of the magnets. Cut 2 new tags (with a hacksaw or slitting wheel on a drill) the equidistant the other side of the centre of the magnets. Click here for a diagram.
6. Clean all traces of swarf from the motor and magnets and reassemble using the new tags.
Sounds horrible, but probably takes as long to do as it takes me to type (and I'm quite a quick typist). If you need more assistance, please me.
Fitting Ballrace Bearings
One the motor has been opened, as above, the plain bearings are very easily pressed out and ballrace bearings can be fitted in place. The bearings I have been using are 3/8" outside diameter, 1/8" inside diameter and 5/32" thick.
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