EZStruder adapter for soft 1.75mm filament

[BenTheRighteous]

Awhile back I tried printing with some flexible filament and the stock EZStruder would do an excellent job of getting my hopes up by printing successfully for awhile, but then mangling the filament every time.

Relevant posts are here: http://forum.seemecnc.com/viewtopic.php?f=37&t=7147" onclick="window.open(this.href);return false;

Long story short, I ran with guanu's idea of fully constraining the filament path - I initially installed some plastic tubing that was cut to size, but it eventually wore out and since it was a pain to get just right I decided to try printing a replacement instead!

This is what I came up with: http://repables.com/r/550" onclick="window.open(this.href);return false;

The idea is the same is guanu's, you flip the EZStruder to the 3mm side, but instead of drilling your EZStruder and installing PTFE, you just slide this print into place instead!

I won't lie, this isn't the easiest print in the world because it's so tiny, but ever since I installed mine I haven't had soft filament bind up on me even once.

I tried to take some pictures but I couldn't get a good angle with my camera and it refused to focus. Next time I have my EZStruder taken apart, I'll take some and post them here.

[mvansomeren]

Since a lot of us don't have a .25mm nozzle, maybe you would consider printing a selling a few of those. I would be willing to pay for it.

If you would be willing to do that, please send me a PM.

[McSlappy]

That's cool. I had the bowden tube mod on there for some time and it worked great for TPU.
I do have some particularly soft filament right now and the issue is that it's soooo soft that it gets squished by the hobbed roller then wont fit through the opening of the bowden tube anyway

[BenTheRighteous]

Since a lot of us don't have a .25mm nozzle, maybe you would consider printing a selling a few of those.

I hadn't considered that before you suggested it...! For anyone who's interested, I'll print up a batch "soonish" (within the next couple weeks) and offer them up for sale here. They're so tiny I can't really see myself charging more than a couple bucks + shipping.

One thing is that I don't know the best way to ship them - they'll definitely need lots of padding, otherwise they'll snap in transit. So maybe one of those small flat rate boxes from usps, filled with bubble wrap?

I do have some particularly soft filament right now and the issue is that it's soooo soft that it gets squished by the hobbed roller then wont fit through the opening of the bowden tube anyway

That stinks, I wonder if there's some other mod you could try - maybe find an appropriately-sized o-ring or rubber band and wrap it over the teeth of your hobbed gear? Might provide good grip while also padding the filament. Emphasis on "might," lol.

[Eaglezsoar]

Selling them on the Forum is a great idea!
Thanks for coming up with the idea and it will help a lot of people having difficulty printing this small part.

[wcarver1]

I do have some particularly soft filament right now and the issue is that it's soooo soft that it gets squished by the hobbed roller then wont fit through the opening of the bowden tube anyway

After I ground the stock roller smooth with a spool of CF-PLA and a 27 hour (failed) print, we replaced them with these: http://store.makerstoolworks.com/extrud ... e-for-mm3/" onclick="window.open(this.href);return false;

They required a ground-up redesign of the cold end as the pitch diameter was smaller, but the tooth profile is perfect for 'squishy' stuff like Hytrel, NinjaFlex, etc. They're super aggressive on stiffer filaments though; I've had to back down the acceleration numbers on the extruder steppers and reduce the spring tension on the cold end to keep the hob from chewing into the filament on fast retracts.

I wonder if there's some other mod you could try - maybe find an appropriately-sized o-ring or rubber band and wrap it over the teeth of your hobbed gear?

Polyolefin (heatshrink)? The exterior of the tubing may have just enough surface energy to do the job...