FAQ

Q: How do I get help with any print troubleshooting?

You can read through several links and documentation here: bunnyPAPRdisclosuresV1

CTRL-F and search this page.

If you are a nerd (and we mean that in a good way), go to http://tinyurl.com/bunnyPAPRInternational . Join the Discord chat server (it's like Slack). Look through the `troubleshooting` channels and start in the `#start-here` channel.


If we get big, we'll do something on stackexchange. If you have high points on stackexchange, please create a tag for `bunnyPAPR`.

Q: I’m a really busy doctor. Can you please tell me everything I need to know about bunnyPAPR use, parts, and disinfection in 20 minutes? Especially the filters.


A: There are several ways to answer this question. See this link.


Q: I'm having trouble printing in PETG

You might need to adjust your print temperature, dehydrate your filament, or change the nozzle size. See tinyurl.com/bunnyPAPR, steps 15-18, and the notes on Thingiverse.

Q: Why can't I print in PLA?

PLA has difficulty with 70% alcohol which is a common cleaner in hospitals. PLA melts sometimes. PLA parts are generally considered 1-time use. The physical properties make them less durable. PETG parts can probably be used 5X as long. So, even though PLA is cheaper, it's more expensive in the long run because it's less durable. For these reasons, PLA is not recommended.

Q: My PETG print is stringy. I print fine in PLA. How do I fix this?

(answered by a bunnyPAPR maker)

short version: dehydrate your spools and don't let them re-absorb water.

long version:

I can only get 24 to 36 hours of good, low stringing print time with freshly dehydrated PETG spools. That is with the spool in an acrylic box with silica packs during printing. I'm not not in a super humid environment. RH% is 35 to 38 at my printers (when their enclosure is at room temp). A really good deal on a food dehydrator right now is https://www.amazon.com/VonShef-550W-Tier-Dehydrator-Machine/dp/B07KPLH5RX Drying the PETG is particularly helpful with the higher than usual print temps we need for good inter-layer fusion in BunnyPAPR parts.

My temperatures and processing times - ALWAYS TEST NEW DEHYDRATOR WITH SMALL QUANTITY OF FILAMENT AND DOUBLE CHECK ACTUAL TEMP WITH A SEPARATE THERMOMETER. ONCE YOU VERIFY TEMP SETTING ON DEHYDRATOR YOU CAN PROCEED TO DRYING FULL SPOOLS. My times and temps differ a bit from recommendations on the PrintDry website, but have never ruined any spools with overcooking. My experience is with 2 Kg spools. Smaller or partial spools are dryable with shorter times. Keys are to stay below filament glass transition temperature and also allow enough hours at temperature to outgas and diffuse water vapor from deep inside the spools. You cannot achieve drying with just putting a spool into a box with desiccant. Post drying, most filaments yield less stringing at higher print temperature. Also, those nasty extrusion gaps from water vapor expanding in the hot end are gone. For Priline polycarbonate (with/without carbon fiber) drying allows another 15 to 20C hotter nozzle during printing without stringing.

Temps listed here are in F because my Gourmia dehydrator only has F degrees readout and changes temp in 7F increments.

  • PETG 158F (70C) x 4 to 8 hours -- This is a bit hotter than PrintDry recommends. Initially, I dried PETG at 149F (65C), but after some 24 hour long tests showed my PETG is fine at 158F, I just dry PETG at 158F. Comes out fine and lets me process PETG at same time as polycarbonate

  • Polycarbonate 158F (70C) x 10 to 20 hours -- Makes a huge difference in stringing especially if you plan to print at high end of temperature range for better fusion. Drying a fresh factory sealed spool just 5 hours helps, but is not really long enough.

  • Silica Gel Sachets 158F (70C) x 10 to 20 hours -- These regenerate in same run as PETG and PC. They simply go in bottom of dryer.

  • PLA 149F (65C) x 4 to 8 hours -- Mid temp and relative slow water absorption allows shorter drying time.

  • TPU 129F (54C) x 10 to 24 hours -- low temperature means extended drying time. Still stringy even when dry.

  • Ninja Flex 122F (50C) x 24 hours -- comes from factory without any real humidity protection. Really low temperature requires a long time to dry. Large difference in overhang performance wet vs dry.


Updates:

5/15, 5/20, 6/29