Hey everyone,
Curious to hear about the successful experiences of using Nylon 11 CF. Have been having a lot of failures and was curious about tips and tricks you all use to print this awesome material!
Heyo! Printing half to 3/4 of CF a day.
We use a stick on a motor which mixes the hopper every 15 mins or so. Don’t mix with a paint stick cause you don’t want to compact the powder, mixing enough to make the powder drop but not compact is key (we still use a paint stick to get the powder to drop halfway through the print). Use a time controller and high torque motor. We always fill the hopper so it doesn’t run out, if it gets too low the nitrogen starts to leak through the hopper.
CF, and apparently TPU, actually crushes into itself above the 3/4 chamber mark; so parts above that are stretched and are dimensionally inaccurate. Formlabs said they’d fix this with a software update, but no joy for a few months now.
Checkout my other post for print settings we’ve found to best prevent warping. We also always fully pack the build. Use small parts to “copy and fill gaps”. Normally getting 25-35% packing density. It’s all about holding the heat in. Don’t take it out of the printer until it reaches 50c, and then don’t unpack until it’s fully room temperature.
Let me know if you have any questions and if you ask nicely maybe I’ll share some links and STLs (it’s also just late and don’t want to find them).
p.s. don’t use the Sift fresh powder hopper, big pain. Set your sift refresh fill to 0%, it’ll fill about 2400 grams (cartridge is 1800g), put the cartridge on a scale and add ~1000g fresh powder. It’ll all fit and you can get 3 fills from one jug and that’s 40% refresh rate. And if your getting 25-35% packing density you shouldn’t have waste, unless your wasting time scrubbing your parts in the sift.
Are you listening Formlabs? 
Thanks for this detail. This is basically what I feared; that this material is very much an R&D process but being sold as a production material. Hopefully the folks at Formlabs take some of this to heart so that the potential of this material can be unlocked. The physical properties are very appealing, and if it printed reliably, it would be an unbeatable material compared to any other production method! But if it’s this finicky, we are better off printing these parts in PA12CF FDM which has similar / slightly better material properties and (surprisingly) fewer printing difficulties.
For now, we are switching our fuse over to PA12 for now and will check back in a few months.
Hi @TappAirsoft, thank you for sharing such a detailed breakdown of your experience with the material! It’s very helpful for our team to understand the specific challenges, and we’ll let you know once we have any updates to share regarding these workflows.