Design Concept:

THIS IS AN UPDATED VERSION

1) I designed new arms for an already (in my humble opinion) awesome spool pusher design by "shinzuriki". I printed the modelers project and all went well. Every feature is well designed and implemented. I did, however, run into a problem as when I loaded a larger spool (200mm), the front roller was pinched between the spool flange and the lid of the CFS. After taking a look at the situation, I opted to elongate and curve the arms to follow the 200mm flange diameter. Although not necessary, in order to maintain "balanced" pressure on the spool flanges, I also printed them for the back roller. Contact is maintained and interference is no longer an issue, no matter what the spool diameter is (not mini-spools, of course). Also, I doubled up on EACH of two rubber bands thus effectively doubling the pressure while (hopefully) doubling the life of the bands as in theory, each now carries half the load. The thing is not a beauty aesthetically speaking, but in a pinch (and with full intention of future beautification) it suits the purpose beautifully, and it prints nicely.

2) After testing the new arms with the original rollers, I discovered that the rollers can tilt into and between the flanges on the wider flanged spools so... I redesigned the rollers by simply adding keeper caps on each end. The .3mf file for printing the NEW rollers (and alternatively the keeper caps for anyone who has already printed the original rollers and does not wish to reprint them) is contained in this project file. You can easily glue the keeper caps on the rollers if you have already printed the rollers! There are no longer any issues with this CFS Spool Pusher which again I must give accolades to the creator for designing. Thank you, "shinzuriki"!

3) Further testing of this enlightened me to another situation. When loaded spool is on the smaller side (in this case 194mm) and the filament is running low, the reduced weight of the spool on the drive rollers of the CFS unit causes slippage. My solution to this (while ultimately utilizing a spring in lieu of the rubber bands) is to add more rubber bands! I now have four (4) doubled up (figure eighted) rubber bands in place and the increased pressure more than suffices. Again, I will be upgrading to a spring mechanism in the near future, but for now... if it ain't broke, don't fix it!

4) Proof that testing is important... feed works perfectly down to an empty 194mm spool with the additional band pressure, but retraction is slipping still. Temporary fix, yet another doubled rubber band if it will fit else weighted spool center. Can't wait for the springs to put an end to this saga. I hope you appreciate my keeping you informed about a work in progress.

5) I have modified the rubber band hook such that it will accept more or larger rubber bands. I rounded the end as well to reduce chaffing of the bands. Additionally, I moved the hooks a bit further toward the rollers so that the use of the same rubber bands will result in increased pressure on the spool as the span is increased between them.

Purpose:

To eliminate an interference problem while maintaining functionality.

Printing Suggestions:

Look, I'm not going to pull punches here... PLA is much more useful in situations like this than most makers seem to give it credit for... and it is typically cheaper than alternatives and faster to print. That being said...

1) The CFS unit is NOT heated, so no worry of deformation (melting).

2) Although the jury is still out, I see these, made of PLA, holding out for longer than I will live. Friction wear? Come on, man!

3) I use Silicone Lubricating Grease with PTFE for friction contact areas, and so, I will be using just a bit between the rollers and their corresponding roller grips, just because.

Assembly Instructions:

Simply attach the new arms to the original base per the original model. There is no difference (model-wise) between this project and the original, except for the arms and print settings which I geared toward part strength.

"Problems really don't exist... because solutions do."

(CCS Interpretations)

Think about that, and have an AWESOME rest of your day!