¶ Your First Print
If you've never used a 3D printer before, try doing a very simple first print. Even if your goal is to print all the pieces to a life sized articulated Darth Vader, starting small will help get you acclimated to using the printers and their tools.
Start with the defaults - stick with the nozzle that's installed on the printer, probably 0.4mm. Use PETG or PLA filament, those are the easiest to work with.
Try printing Benchy as your first model. Use the slicer to scale it down so that it takes 11 minutes rather than 45. Try rotating it in the slicer. Try duplicating it. It's a good benchmark (get it?) for printers and an easy model to work with so that you can get used to the slicer.
¶ Choosing Filament
Unless you have specific requirements for a different filament, you'll almost certainly want to use PETG or PLA.
PETG is a good general purpose filament. Most of the filament we have is PETG.
PLA is also general purpose but has a lower melting point. Items printed in PLA may droop even inside a closed car in the summer.
ABS is a durable filament that's good for things being kept outdoors. So is ASA. Both produce gasses that give some people headaches so we avoid using them unless necessary.
Please see Prusa's Material Table for more information on different filaments.
Some filaments (for instance, carbon fiber or filaments with embedded metals or wood) may wear down print nozzles quickly. Some filaments may require assistance to adhere properly to the print plate, or may adhere so strongly that they may damage the plate. If you're using any kind of unusual filament please be sure to research it on the Material Table page.
¶ Picking a Printer
Unless you have a large printer that won't fit in one of the smaller printers or need to use multiple filaments in one print, please use the Prusa MK4S printers rather than the XL. We try to keep the Prusa XL available for jobs that require it.
If none of the Prusa MK4S printers are available or you need the features of the XL then please use the Prusa XL.
Several of the printers have a secondary outward facing display and printer monitor in their enclosure. The displays will show the currently loaded filament type and nozzle size to help you locate a suitable printer. During printing the display should show the remaining time although this has proven buggy.
¶ Connecting to a Printer
We use PrusaLink to connect to printers over the network. You must be at CTRLH to do this.
Each printer has a sign over it that has its name, model, and a QR code for PrusaLink on the printer. The QR code is for a URL that has PrusaLink's credentials embedded in it. The URL will look like
http://maker:PASSWORD@prusa-1.ctrlh
Your phone's camera application should be able to decode the QR code.
We don't currently support PrusaConnect. We've had a lot of issues with printers being available on it reliably, and there are many problems using it in a multi-user environment like ours.
¶ Printer Name Doesn't Work
The printers have names like prusa-1.ctrlh and prusa-xl.ctrlh. We use the names to avoid dependencies on IP addresses which may change over time.
You must use PDX Hackerspace's local name servers that are assigned by DHCP for these names to resolve. Names in the .ctrlh domain will not be work with any other name servers. If you override name servers on your device to use servers like 1.1.1.1 or 8.8.8.8 you'll be unable to use these names.
If you're using the local name servers and still can't resolve the names please post to #3d-printing or #help for help.
¶ Long Print Jobs
It's okay to leave a long print job running. Please stay for the first few layers to make sure it's adhering properly to the print plate.
It's helpful to leave a plastic bag with a note on it if your print has multiple parts.
¶ Monitoring a Print
Join the #3d-printer-jobs Slack channel to see updates from the printers in real time.
¶ Completed Prints
If you need to use a printer and there's a completed print on it, please deposit the print in the white “Lost and Found" bin next to the main entrance. If the print has multiple parts it's kind to put them in a plastic bag.
If the print failed please post a photo and message about it to #3d-printing on Slack so that the person who ran it will have some idea what happened.
Likewise, look for your completed prints in the white “Lost and Found” bin next to the main entrance.
¶ Failed Prints
Prints can fail for many reasons.
Often it's bad filament. Many plastics are hygroscopic - they absorb moisture. And Portland is famously moist. This often results in the plastic stringing or turning into spaghetti. To fix this, dry the filament - you can bake it or store it for a long time in a filament drying box. Or just switch to a different filament for an immediate fix.
If the edges of the print lift up it may be cooling too quickly, which is likely to happen in the winter. Make sure the enclosure is closed.
If you're printing multiple objects try reducing the number or just printing them one at a time. Or try printing them more slowly. Try “draft” or “quality” settings rather than “speed”.
Sometimes the model itself may be defective, or may need a brim or supports. Check out organic supports in Prusa Slicer - they're effective, save filament and time, and look really creepy.
Ask for help if you still have problems.
¶ Cleaning Print Plates
If you have any problems getting your print to adhere to the plates you should try cleaning them. Even fingerprint oil can interfere with adhesion.
The plates attach to the print bed magnetically. You should be able to push them around and pry them up off the bed.
The plates are double sided. You can print on either side.
To thoroughly clean the plates, wash them in warm soapy water, then dry them and wipe them with a paper towel with 90% isopropyl alcohol (IPA, not the drinking kind).
Never use metal brushes or pads to clean the plates or you'll damage them. Acetone will destroy the finish on satin plates - best to avoid it altogether.
If plastic is stuck on the plates try heating them up and scrubbing it off with something non-abrasive.
Ask for help if you need it.
¶ What About Octoprint?
OctoPrint is open source software that provides a flexible extensible web interface for 3D printers that's generally run on small computers like Raspberry Pi's. We used to use it but as we've moved to only Prusa printers we no longer need it and are no longer using it. Any references to OctoPrint at CTRLH are out of date and should be ignored.
OctoPrint is still an excellent piece of software. We're not using it because we don't need it, not because of problems with it. If you have a home printer and need a networked interface to it, we recommend it.
¶ Getting Help
We all need help with things sometimes. If you need help with 3D printing, please post to #3d-printing or #help on Slack.