Cantilever Filament Spool Winder (MK1)

UPDATE:  I have published my Canterlever Filament Spool Winder (MK2).  This touches on every part.

The overal dimensions and shapes are much the same, so some parts from the MK1, will work fine with the MK2.  So for example, if you would like the updated handle this will work with with the rest of the parts that were already printed.  The frame, wedge nut, spool nut, and end cap are fully interchangeable between MK1 and MK2.

However, if you would like the new crank handle, you will need the crank shaft, crank handle and the gear from the MK2.

I wanted something I could attach from the side, instead of mounting the spool to a shaft and then attaching the apparatus to the winder.  Now it has fewer actions to do this.  Was there any necessity to do this? -No.  But it was a good learning experience, and it gets closer to what I wanted.

This is my first working revision.  I am “working” on another iteration.

Assembly notes:

The handle shaft can be forced through the handle proper, but may require heating to soften the end to allow it to flex.  The ring snaps over the clip, but the clip may need to be press back into shape, depending on how much you softened it.  Be sure to break apart the handle assembly into its three parts in the slicer.  Uploaded as an assembly so it is clear how it comes together.  Once assembled it is pretty secure and resists coming apart again (to the point of breaking).

The crank handle and spool shaft end cap both use the same thread profile.  While interchangable, the threading would unscrew if used to wind the spool over the top.  But you could still do it if you added a rubber band in between and didn't want the counter rotation.

The original spool shaft is a bit long (pictured). I included a version cut down by 40mm (150mm).

Design considerations:

• I have tested only one print, but it came together without any issues.
• Gears only set to counter rotate the spool, so are 1:1 ratio.
• The crank is strong enough to afix the nuts on the spool shaft, but not to torque any of them down.  Don't tighten with the crank handle in this design.
• The spool nut can have some sort of grippy materal added to prevent spool slipping, which reduces the need to torque the wing nut.  I used two rubber bands interleaved across the notches, but stick-on rubber or a TPU gasket would work too.
• Spool nuts can be configured to the ID of the spool as required, but isn't strictly necessary.  I included examples of 53MM and 56MM, since those were the sizes I needed.
• I suspect printing the frame on its “back” instead of the bottom may be stronger, due to layer adhesion strength, since the countilever design will pull up on the far side wall (from the load).  But that may only be an issue if you load up a 3KG spool.
• May or may not be able to hold a 3KG spool.  I don't have a 3KG spool, so have not tested it with this.
• The spool 190mm shaft may be too long, depending on your use case.  Recommend the 150mm version for most 1kg spools, but it may be a bit long for 500g or less.  Can be edited, or cut in the slicer to be shorted as needed.  The winder in general was designed with the flexibility of spool sizes in mind.
• The handle may be overly complex.

Future design thoughts:

• Simplify the handle design.
   
• Make the spool nut chamfered for easier mounting of the spool.
• Chamfer the wing nut screw edge to make it easier to thread.

OR

• Do away with the nuts, and figure out a springy attachment method. Alter spool shaft. (TBD)
   
• After thinking about it, seems highly unlikely anyone would put a 3KG spool on this.
• May narrow the tower section of the frame to better suite spools =<1KG.
• Make the spool shaft end cap easier to grip.
• Gears probably don't need to be so wide.
• Moderate torque can cause the crank handle screw to delaminate.  Needs reinforcement, or may change to key slots like some of the other parts already are.
• Reinforce the platform.
• May flatten the centre hole to allow a better fit for a clamp.