I designed the PET bottle filament winding spool to be much smaller than the model I had, I used three stages of satellite gears to achieve a 1 in 64 reduction and as you can see in the pictures it is much smaller than the traditional one with regular gears. It is also very quiet. It has a coupling system to release the spool and be able to unwind the filament once the process is finished.
IMPROVEMENTS MADE
I incorporated a filament sensor in the guide so that it stops automatically when the PET strip is finished.
I added a system to easily anchor the filament tip to the spool.
On the back I put an adjustable limiter so that the filament does not unwind when it is finished.
I designed a front and rear crossbar to fix the side legs in the exact position and make it self-supporting.
I improved the design and dimensions of all the parts for printing. For example the reel I divided it into three parts and optimized the coupling between them.
I improved the clearance between gears to make it run smoother. The motor became 5mm further into the spool.
Materials:
Nema 17 motor
608 (any model) bearing for rear leg shaft.
4 bearings 623 (any model) for coil support
12 screws M3 x 30mm to join the three parts of the coil
4 screws M3 x 30mm to fix the front leg and 623 roulettes
4 screws M3 x 10mm to fix the motor
2 capscrews M4 x 5mm to fix the pinion to the motor
Piece of threaded rod M8 x 40mm for rear axle
3 hex nuts M8
4 or 5 M8 washers
2 M3 x 10mm screws to fix the roll limiter.
6 Wood screws to fix the coil to the machine base.
2 Shafts 6mm thick by 100mm to 120mm long (I get these from a spent toner cartridge).
-1 M8 x 100mm threaded rod at 120mm long (can be plain rod as well).
-1 M3 x 12mm screw for the filament guide wedge.
It is very important to pay attention to the order in which the parts are assembled.
1st the pinion is fixed to the motor
2º place the motor in the hole of the front leg
3º place the motor fixed part on it
4º fit the 623 bearings in the holes of the motor mounting piece (they will then be tightened in position with the leg screws).
5º color the 36-tooth crown wheel and fix it to the motor with the 10 mm M3 screws.
6º fix the front leg and the 623 roulettes to the motor mount with the M3 x 25mm screws.
7º place 3 12-tooth gears on the free carrier and insert them inside the 36-tooth ring gear as far as they will go.
8º proceed the same as the previous step with the other free carrier.
9º press the 608 roulette onto the spool carrier and insert the threaded rod shaft with the nut on the inner side.
10º place the last 3 gears on the spool carrier and insert it inside the crown wheel.
11º join the front and rear parts of the coil with the 6 conical head screws and insert it on the crown.
12º Screw the locking nut on the coil holder
13º place the rear leg on the axle separating it from the roulette with two or three washers and fix it with the other nut.
14º it only remains to fix the legs on the base of the machine, where appropriate so that it is aligned with the nozzle.
UPDATE:
For assembly with the winder, the one-tooth crown must be screwed together with the back of the coil.
Then the assembly is very simple, proceed when the long rear leg is to be fitted.
I just uploaded the Marlin used on the megaramps board and the STL files I use with the machine.