Has anyone been able to print with PVA successfully on the H2C dual extruder?
I have been attempting to test print with dual extruder a white PLA Benchy with PVA supports to figure out the settings, however the PVA supports continue to fail after the second layer because it separates from the base layer. Pictures of fail attached at the end.
I’ve attempted to slow down the print speed and decrease base pattern spacing. I use a glue stick to help with bed adhesion. The bed and nozzle temps are within the parameters for the PVA (Sunlu PVA on Amazon). SS of settings attached.
Any advice on how to make it work would be greatly appreciated! The end goal is to start printing PVA supports for Architectural Models.
Yes I did dry it before using my AMS Pro 2. I have a bunch of packets of desiccants in there as well.
When I was watching the first couple of layers I noticed that after the base layer was printed, the first layer of the support pattern would print, but not bond to the base layer. When the print head came back to print the second layer of the support pattern it would detached the previous layer and make a mess.
I am wondering: maybe I need to increase the bed temp for after the first layer?
I have to wonder if loading desiccant in an active dryer is causing problems. It can help when the dryer is off by scavenging water but when the Pro 2 heats and drys, if the silica gel has much water, the Pro 2 would be needing to remove water from the desiccant as well.
If you aren’t frequently regenerating the beads (maybe you are), they could actually be slowing drying and keeping the Pro 2 from hitting as low of humidity in the drying chamber.
PVA is very hygroscopic so any dryer needs to be in top form.
Absolutely correct - silica can hold up to 40% of it’s own weight in moisture, and it gives all that up easily when heated, so if you have 50 grams of saturated silica in there, turning on the dryer can release up to 20 grams of moisture into your dryer. A larger or more full roll of filament is not going to warm nearly as fast as the silica, so you’re pretty much putting your cool filament into a steam sauna. That moisture is gonna get absorbed.
As MZip said, your silica needs to be in tip top dry condition or you’re slowing down the process drastically.
Hi guys! Thank you all for your input! Just wanted to update and say that with the comments (and more research) I was able to determine:
I didn’t have nearly enough desiccant, so I bought some renewable kind
Drying the PVA with the desiccant inside the AMS wasn’t actually drying, so I pulled the filament out, dried on the print bed low and slow (35C for 15ish hours because I wasn’t at the office to flip it half way) and then swiftly loaded it back into the AMS after
Needed to turn off the part cooling fan! It was cooling the PVA way to fast to be able to adhere the layers.
Some other small changes to temperatures and speed, especially when trying to print PVA onto a PLA surface.
I’m happy to report that it is finally working! I’m still playing with some of the settings to see how efficient I can be on speed, material use, and end quality.
I’m teaching someone now how to 3D print, so I’m keeping a Excel cheat sheet for settings in case any of my user presets get override. If anyone needs a basis, these are the settings I’m currently using.
