This is my build log for the MIDI Player motor build I have made.

Here is a shot of the motor after removing it from its mounting plate in the player:

I managed to almost buckle the shaft mount of the Can while banging out the rotor shaft as I wasn't sure how they got it in there. Lesson learnt, remove the little backing plate from the rear and take off the copper clip holding the shaft in place.

I punched out the centre brass sleeve from the stator and wound it up with 15 turns of 30 gauge:

Removing the Rotor revealed what I thought was a plastic face with a flux ring mounted in it. Cutting away the plastic revealed that there was a whole metal Rotor there but it had been pancaked both sides in plastic - so I cut it all away - straightened the shaft mount and polished it up. A bonus was all those 'cooling holes' were already there to keep both plastic sides together!

Next I mounted 8 3x3x0.5mm magnets I had purchased from olmodfrom RCGroups a while ago - I knew they would come in handy one day.

I went to another LHS yesterday and found some metric tubing perfect for the job - so still no lathe work done. 4mmODx3mmID aluminium tubing for the stator mount and 1.5mmODx1mmID brass shaft sleeve.
AUW so far is 1.7 grams.

 

The bearings arrived this morning so I wasted no time installing them into the stator shaft. I almost thought they were too small when I saw them as I have only seen the flanged type.

I hooked up the finished motor to a CC 10A esc and 2 cell 340mah kokam. The motor absolutely screamed at up to half throttle with the 2.5" gws prop and even faster with the cut down prop - I didnt dare throttle up any higher! It got hot, which is to be I expected as I have wound this for a one cell 90mah cell. Now that I know it runs great, next I will test it on the BLC-1 esc and 90mah cell and see how it performs.



AUW for finished motor is 1.78 grams!!!

So far I have had to increase the winds to 28 turns as 15 turns was just too dang hot! The motor runs cold but I can't run it WOT as the blc gets too hot. And that was testing on a 210mah lipo. I tested it on a 145mah lipo and it couldn't deliver top end current at WOT, so I am still too hot for the battery and ESC. I may have to step down in wire size and throw a bunch more turns on it as it has sufficient revs at half to 2/3rd throttle for my needs. Full throttle was just crazy. So I think I will try for ~50 turns of 30gauge and see how that goes next. AUW with extra turns put it at 2.0 grams. This shouldn't move too much with the new wind. I think for now I will run 160 mah lipos as I have a bunch of them that have yet to be used.

Final progress is I tried 36 winds of a paired 30 gauge wind and it was still drawing too much current for the esc. The motor ran fairly warm. I wound 36 turns of the orginal gauge and that was a real tight fit. I had to squash the coils down to get the Bell back on! It still runs the ESC hot at WOT and the motor was stone cold with these windings. My only conclusion is the airgap is requiring a decent amount of current to get things going.