Aeromartin's Modified Rubber Winder (No. 5425305) - eliminating the need for wire axles

thingiverse

Aeromartin's rubber winder (No. 5425305 on Thingiverse) is very well designed and very nice in terms of ergonomics, but I was able to improve it to make it easier to make. 1) The use of music wire axles for the gears. Cutting the 2mm music wire is best done with a Dremel with a reinforced cut-off wheel, which is fine, but this re-mix replaces the wire with 3D printed pegs, which are much easier to produce and eliminates the need for cutting 2mm music wire. 2) The zig-zag bend at the end of the output shaft is difficult to do accurately. This re-mix replaces the zig-zag with a simple L-bend or Z-bend (particularly easy to do if you have a Z-bender tool, but which can also be done simply with pliers, and without need for accuracy. 3) The Face Plate's flanges on the original extend too far, they have to be filed back before the Face Plate will fit onto the Main Case. I have removed some material from the flanges so that the Face Plate will fit without need for filing. 4) The holes need to be drilled out - the ones for the screws all need to be drilled out to 2mm, the ones in the Output and Output Base need to be drilled out to 1.2 or 1.3mm to fit the output shaft. I have not addressed this, it is good to have a cordless drill when tackling this project. The new files being provided here are the Face Plate, the Main Case, the three gears and the Bearing Peg. Obtain the rest of the necessary files from the original Thing, No. 5425305. It is best to print the Bearing Pegs separately from the other parts. As with anything narrow and tall, use a wide Brim (maybe 4-5 lines). You can print many at a time. As designed, the pegs are 4.9mm in diameter and 10mm tall, if you want them flush with the outside of the case reduce the height to 9 or 9.5mm in your slicer. Also experiment with different diameters - with certain brands of filament I found I had to reduce the diameter to as little as 94% - you want a moderately easy press fit in the gears (the ridges from the layers will keep the pegs from falling out). I like PLA-F, you can probably find it on Amazon. It prints accurately, sticks well to bare glass, produces dimensionally accurate parts and drills and files easily. If you can't find it, I'd suggest some variety of modified PLA - "PLA+", "PLA Pro", etc. Problem is they're not all alike, some work better than others. I like printing with 0.8mm lines while using a 0.4mm nozzle. If you are using Cura 5, the slicer will automatically reduce the line width where needed, and these settings produce very strong parts (try finding the CNC Kitchen video on YouTube on this subject). The best source for output shaft material is music wire sold for use as pushrods for small electric RC models. Some already have Z-bends in them. I like to make diamond-shaped hooks (Peck Polymer style), they're easy to bend accurately (see photos) and the rubber motor doesn't tend to climb them as much. You can easily cut the 1.1 or 1.2mm music wire using a diamond file from Daiso - file a notch in the wire, and then bend back and forth a few times with pliers. You can also use to diamond file to deburr the tip of the wire where you will form the hook. I find 80-85mm is the correct length for the output shaft. As Aeromartin says, it's best to lube the gears. I lube the teeth and the bearing surfaces using the grease they sell for 3D printers - you can also use the grease they sell for fishing reels. My next project - modifying this winder for outdoor use and heavier rubber motors. Reduce the gear ratio to 1:7.5 or 1:6, and use a heavier 1.5mm output shaft.