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AC Motor and Alternator Test Platform (New Motor/Pulley)

Took carbednotch's recommendation and upgraded the AC-Motor for higher horsepower and RPM output. (1HP, 3450RPM) Even upgraded the main pulley ...

Quincy QT-5, 3HP, Large Motor Pulley

Reeves Drive In Action

diameter. At the same time, the motor pulley comes closer together and pushes the belt up onto the larger diameter - so the motor pulley increases ...

Quincy QT-5, 3HP, Small Motor Pulley

Threaded Pulley for MakerBot CupCake Extruder

All along, I’ve been having trouble with the filament feed on my CupCake extruder. Regardless of how closely I position the idler wheel to the drive pulley, the slightest blockage at the extrusion nozzle (even sometimes removing the text extrusion with needlenose if I get too close) causes the timing pulley to ream out a pulley-sized divot from the soft ABS.

There’s then no way for the extruder to move the filament — forward or backward — until I get pliers and apply considerable force to the filament at the intake to move the divot past the pulley.

In April last year, nophead tested different drive methods and found the threaded pulley (as above) to provide the strongest grip on ABS. (Search in page for “The final test was a threaded pulley” to see his technique and results.)

nophead isn’t the first to use this technique to manufacture a threaded pulley and I’m not the first to copy his notion of using it on a RepRap, but I’ve lost my links to many of those who have done it before.

At any rate, I installed one on my CupCake this weekend and the results are considerably beyond my expectations. Here’s the story.

I got in touch with my friend Mike Smith from Pittsburg (as opposed to my father-in-law Mike Smith from Hugoton) works in the university’s technology center where he has access to all kinds of machines, has a metal lathe at home, and for fun does things like hand-rewind the coils on CD-ROM drive pancake motors to make new motors for small electric RC aircraft. I described what I was after and asked whether it was something he’d be willing to take on.

My project piqued his interest — he sounded amenable and asked for more information about dimensions. I offered repeatedly to take apart my machine and confirm the pulley and motor measurements, but he was satisfied with the dimensions I found on the existing timing pulley’s datasheet. Within a matter of days Mike had machined me two beautiful threaded pulleys and sent me the pulleys and the following information about their manufacture:

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