This week has had its up and downs, and even more downs.
I got my 3D printer fully up and running. I even got a few test prints done. So, let’s start with what I have been doing. I’ll to try to go in order. It helps that I have been keeping a list of what I have been doing, what I have learned, and what I have plans to do in the future.
What I have learned/done
- Supports are not always needed when printing in PLA. However, there are some points when they are necessary.
- The nozzle fan wasn’t working and it took me a little bit to figure out why. The blower attachment that came with the kit sits a little high in the housing so it was interfering with the fan blades. I pulled it down just a touch and that fixed the problem. The fan is important when printing, because it helps keep the filament from getting too hot and making uneven prints. The downfall to this however is that it so that I can’t see the starting of the print because the blower is so big. Disappointing really because it actually worked well.
- I did a test print from a design I found on http://www.thingiverse.com. It was a little Star Wars Stormtrooper helmet pen cup. I didn’t scale it up though so it only fits toothpicks. Still cute though.
- One of the main things I learned with the stormtrooper print was that I installed the bed upside down. And it is also very very important to prep your print surface so that the print releases when it’s done. Because I messed up (because I didn’t know) I accidentally pulled part of the thermistor off. It made it so that the entire printer wouldn’t work until it was fixed. I panic ordered a whole new bed, because I wasn’t entirely sure as to what I had done. Once I figured that out I ordered a set of new thermistors with one day shipping. When they arrived I removed the old one and soldered a new one on. Once that was done I installed the bed again – the correct way – and the printer worked fine again. I also got some glue – I use Scotch clear glue with a meshy applicator – and prepped the surface for a new print with that and some masking tape. I’m glad the internet was there to help. I have since ordered print films that stick to the bed, but I still have to do a bit of glue prep on the surface to make sure that the printed pieces come off when they’re done.
- I got my first bunny test print done on Tuesday with my white filament. I did a 1.5mm shell with a 20% infill on a 5″ tall model. It came out fairly decently. There was a little bit of an issue with layer adhesion. I think it had something to with the temp of the filament. I think it was not quite hot enough.
- I found out through internet research that a heated bed is not needed when printing in PLA. And actually having a heated bed can cause some issues like warping at the base of your print. I saw some first hand experience in a couple of my prints. It took me a bit to figure out where in the settings I had to go to turn that off. My prints have been a lot better at the base since I got that to turn off.
- I have been doing some playing around with shell thicknesses, infills, and scaling. I found that for some prints infills aren’t really needed. Vasing works just fine (hallow on the inside). It all depends on the filament and the size and shape of the print that it being done, as well as the filament that is being used. There really is such a thing as too thin of a shell. There is also a thing as too think of a shell. I did one print that had a 3mm shell and that print just took forever. It was just too thick.
- I found out that changing the filament for my machine is a bit of a pain in the butt. Because of how it is designed it is really difficult to feed the new filament end into the tube that goes to the nozzle. I basically have to take the entire extruder fan off so that I can see in enough to feed the filament in. I have switched the filament a couple times and it hasn’t gotten easier. It’s kind of a poorly designed system.
- I had a clogged nozzle after I switched from the white filament to a black filament and ran one test print. The second print started out ok and I watched it for a bit before I had to leave. When I got back I found that the clog had happened some time shortly after I had left. So basically the entire time I was gone it had not been printing. I came back to a 3″ gap of air where I print should be. Having never had to deal with this before it was somewhat a test of patience trying to figure out how to fix it. It involved me taking the whole extruder apart. The clog was easy to fix because it was just a bit backed up in the feed tube. I figure that while I had it apart I would try a different nozzle from the five that I had ordered online. The unfortunate part was that I had accidentally ordered the wrong size. They were either too long or too short depending on how you look at it. It took a bit of tweaking to get the old nozzle back on and fitted tightly. But now I can do it without a problem because I know exactly how the extruder goes together.
- The black filament that I had switched too is crap. even with appropriate temp adjustments it just would not print well and adhere to itself. There were gaps and bad striations throughout the print. The filament got returned.
- I switched to a purple filament (again having to take the extruder fan off to see). With that I printed an 8″ bunny with a 0.8mm shell and a 10% fill to really test the shell infill parameters. This is where I really found a wobble in the threaded rods that attach to the motors and control the up/down (X) movement. They don’t fully reach the top of the frame and fit in the wholes that are designed for them. This means that the print got really bad at the top. bad to the point that there were holes and irregular printing for most of the top of the print. You could actually see through the ears of the print. There were also gaps in the print that kinda ran from bottom to top. I think that some of this had to do more with the shell thickness and not the wobble. I am going to fix the wobble before I attempt to do a tall print again. I have a part to print and I am waiting for bearings to come in the mail this weekend so that I can fix that particular problem.
- I attempted to do another taller bunny (7″). This time I rotated so that it sits in its face, rotated it 45 degrees so that it fit on the bed, and added supports to it so that the shape doesn’t warp. The print turn out nice as far as I can tell. I haven’t removed the brim nor the supports yet.
- I learned that a lighter works ok to smooth out filed or cut points, and re-add glossy shine to a print.
- I got a test print for the disgruntled bunny done. He’s cute, but the vibration echo is there.
The super shitty
- My printer is in pieces at the moment. A screw that is used to level the bed got stuck. I had to separate the hot bed from the h support frame. The only way to do so was to break the screw. Now I still can’t get the screw out. The reason for this is that it has been printing poorly and when I was trying to print a support to fix the issue the new issue arose. At first I thought it was just because of the height of the piece. Turns out there is something more than that going on.
Plans for the upcoming future
- fix the bloody hot bed.
- Do more test prints until I can get about as perfect of a print as possible.
- Test the different filaments that I have.
- Lube the bed rods.
- Try polishing a completed form. (THF?)
- Finish my sitting bunny design.
- Find a way to cool the stepper motors and the power supply. I worry about them over heating.
- Get the supports printed to reduce the wobble and the vibration markings in my prints.
So much to do to get this right. On the plus side, I was able to successfully replace the hydraulic struts for the liftgate on my car. That made me very happy.