I went down a rabbit hole in trying to figure out how to eliminate the idler gear in the maslow 4, and as part of this I started modeling the spool, and then needed to do different ones at different sizes…
So I created a doc where you enter the number of teeth in the gear side of the spool, and the length of belt that you want to have fit on the spool, and it creates it
I flip the belt over to the teeth are against the spool, and make the spool be a spiral out so the next layer of the belt lays nicely on the first, no bump in the additional belt layers. This also puts less strain on where the belt is anchored to the spool, so you can risk unspooling more of it
manufacturing this may be a hassle (3d printing it you have to worry about the overhangs over the big teeth, making a mold for injection molding has lots of detail) but I figured this is useful enough, not just for the maslow, but for anyone doing belt spools, that I split it out into a separate document to make it easier for others to copy.
I like how you’ve added the belt teeth to your design.
Why do you want to remove the idler gear? Is it because of the extra stifness?
I’ve reduced the outer diameter of the geararm which should allows for room to add bearings to the idler gear. See pictures below
besides ‘the best part is no part’ (simplicity, reduced cost)
it allows the spool to be larger (100mm vs 82mm inner diameter), which allows for a larger diameter spindle and/or bearings to be put in place to improve durability
It should make it far harder for the belt to get caught in the gears, possibly allowing the elimination of the belt guard
Ok seems fair. When eliminating the idler gear, the belt gear will turn in the other direction. I would suggest to put the belt notch in the opposite direction or you could possibly rewire the dc motors. Also you might need a bigger gear to provide for enough clearance but this will also change the belt feeding speed.
Ok seems fair. When eliminating the idler gear, the belt gear will turn in the other direction. I would suggest to put the belt notch in the opposite direction or you could possibly rewire the dc motors. Also you might need a bigger gear to provide for enough clearance but this will also change the belt feeding speed.
It really doesn’t matter, this is a DC motor, so just reversing the wires to it
will have it spin the other way (and it has to spin both ways anyway, so it
could also be a config fix)
