When using a public 3D printer such as at a Techshop location or at a maker space consider the following tips and ideas
1) what to do every time you are about to print
2) settings stored in software by other users
3) nozzle clogging
4) PLA left in place
5) what a proper extrude command should produce
When 3D printing different users have different expectations. As a maker who enjoys rapid prototyping I encourage readers to focus on printing and using a 3D printer for at least 12 hours before even considering making a final print that must function as part of a larger design.
It is possible to get great results right away and some of the tips in this instructable will also help home users who have their own machine.
I made it at Techshop http://techshop.ws with a Type A Machines Series 1 3D Printer
Submitted by SFlettering for the Instructables Sponsorship Program
Step 1: Loading a New Model - Restart the Computer First
When loading a new model into pronterface or a similar print control software program you may already have a previous user's model and settings in place. All models are already saved if they are in pronterface and you are best off restarting the computer before you start to print.
The interface between the printer and the computer is solid and can also be reset (but that may be enough to get rid of others users custom settings.)
TIP: You may be able to logout and login again, but creating a consistent set of steps that include restarting a public computer before use is a best practice.
Step 2: Observation of Machine Status - Notice Anything Out of the Ordinary
Note if there are small imperfections in the actual print surface or on the tape as this is an indicator of issues with z-height.
Image 2: Sometimes a user left the PLA in place after a print and rather than heating up the nozzle and removing the PLA they cut the PLA off and left some behind. If you find this make sure to clean the print nozzle too as this is a good indicator of potential nozzle clogging issues. Image 2 shows the piano wire coming up from the nozzle area and cleaning out extra PLA left behind (a bit hard to see if not zoomed in on the image)
TIP: I found that many users when attempting to get the best possible z-height ended up with the nozzle so close it scraped the tape when starting the print.
Step 3: Checking the Defaults in KiSSlicer - a 4 Step Approach
When starting KiSSlicer even after the computer was rebooted I found that the print settings from previous prints were not 100% cleared out from KiSSlicer. Here the model quality was still at 150 based on a previous user's settings.
TIP: As part of your checklist when getting ready to print on a public 3D printer make sure to start with a few basic settings including
1) print temp
2) print quality
3) support options
4) raft layer choices
It could be the case that there are a set of default settings within the software that you can trust, but a step by step approach each time you are about to print is a great way to get the best consistency when printing.
Step 4: Cleaning the Nozzle - Getting Rid of Leftover PLA
To clean the nozzle focus on 2 areas
1) the area around the nozzle can be wiped off with a paper towel (I learned this from watching other users)
2) the nozzle can be clogged from left over PLA
Although cleaning the nozzle might not be required each time. When you are printing something important you will need to either print something unimportant first to clear out any PLA (especially other colors) left behind or clean out the nozzle. Nozzle cleaning is especially important when 2 different brands of PLA are used.
TIP: The nozzle when hot is very hot and can burn you. Safety First.
Step 5: Extrude for a Status Check After Cleaning
After cleaning the nozzle or when deciding if you want to clean the nozzle you can use the extrude command to check if the PLA comes out of the nozzle quickly and smoothly (note that the nozzle must be at the right temperature settings for the PLA to extrude)
TIP: Sometimes the time between the extrude command and the extrusion of PLA takes a few seconds.
Step 6: Pay Careful Attention to PLA Placement
When using a public machine you will most likely have to use your own PLA. When using your own PLA each time you will have to feed the PLA correctly. Here is an example of how PLA can come out of the nozzle even after cleaning because enough is in place, but the PLA will not feed correctly because it is not properly lined up with the track.
TIP: good practice includes double checking your PLA placement and testing with the extrude command to see if the nozzle is working at optimal levels before printing.
Having a routine to do each time you sit down to print on a public 3D printer is a great idea.
I find that it takes almost 30 minutes each time (including a 10 min test print) to be able to make sure the machine is in good repair and ready to print.