So now that people are getting their printers together and getting their first prints done I thought it would be good to start a discussion where we can help each other figure out the best settings for prints.
So I've now printed almost a half dozen benchy's but still haven't had much luck.
Here's where I am so far.
One of these is not like the other. It's not the calibration cube.
So I've tried:
Backed off on the flow rate.
Double checked the extruders steps per mm.
I thought it could be the filament. I swapped from the blue to the red. No difference.
I thought that maybe both spools were sub par so I got a known good spool of Tecbears PLA. No difference.
That brings me to the last benchy on the right. That is printed with the blue PLA that came with the printer. Except, it wasn't printed on the AXIS printer. Doesn't appear to be anything wrong with the filament :(
Some thoughts on things to try:
Fix lead screw and lead screw coupler. There seems to be some odd pop every now and then. At the moment I don't think it's the biggest contributing factor but if everything else was fine I'm sure it would show up.
Fix lead screw wobble. Mine processes around around. Probably in a 1-1.5cm diameter at the top. Such much so that it almost skates off the bracket.
Make new build plate guides. They're either too tight or too loose and the plate wobbles.
The y-axis guides on the gantry. These suffer the cause the same problem as the build plate.
The y-axis gantry itself. It doesn't seem stiff enough. I can watch it sway in the x-axis direction when there are multiple quick moves of the build plate. I'm not sure how to address this. The problem is pronounced when the print head is out towards the end of the gantry.
Part cooling. I'm not really thrilled with it. Cooling isn't a huge thing but I noticed results when changing a set up on my other printer.
The hotend. Not really thrilled with this either. I have one I've pulled off an Ender 3. It looks like it might fight the spacing of the two bolts that the belt are attached to. I haven't measure yet.
I'm kinda grasping at straws here. Thoughts are welcome.
Oh, I also tried setting up the printer in PrusaSlicer. Here's the first benchy:
Some layers at the bottom look good. Then it gets off as it goes up. I'm not too concerned with the stringing. That's something I've yet to figure out how to fix in PrusaSlicer no matter the printer. One thing I thought about when this was pulled off the printer. I think adding clips might help. It's kinda easy to move the build plate. I wonder if that's causing slight layer shifts. This might be especially true with what I consider to be fast travel moves.
Welp, I'm able to print pretty well finally, I think. In the end, it comes down to the eccentric guides are VERY finicky, I think. The TINIEST adjustment makes pretty large impacts, I think. Lots of "I think" because I certainly don't know for sure... I'm just happy to be getting some consistent prints.
In general - I ended up not doing much beyond the instructions that made a difference. I had to follow the "special - oops you might have gotten wrong parts" instructions and extend the heater element and thermistor wires myself. I initially used the 3rd eccentric guide instead of a fixed guide for the z/y axis attachment, but I did get a replacement that I put on, today.
Even with the 2 fixed and 2 eccentric guides now, it is still painful to adjust, but I think I got it after about 20-30 minutes of turning the eccentrics VERY slightly each while having a level on the y-axis boom, and turning the z-axis screw (from lower/stepper part of the coupler) to see how each adjustment felt - easy to turn, then with a bright light above the unit, carefully watching the shadow against a straight edge to see if it moved side to side while transitioning turning from up to down and back again.
The bright light, shadow, and straight edge is the the same thing I did with the x-axis that helped me quite a bit there adjusting those eccentric guides. In the end, I was happy with the very slight movement on transition up/down versus how hard it was to turn the z-axis. Maybe I could get it even better... but the print quality is good enough to make me happy. No more wavy edges on the archway on the benchy! Yay!
If anything, I think my shadow & straight edge method to adjust the eccentric guides is about the most important thing I can contribute to the "what else can I try" list of things that people have suggested. Keep making minute adjustments to the eccentric guides until you don't get shadow shifts when changing directions, and things move easily while turning by hand.
So, what have I done differently from the instructions to get the results I'm getting?
1) $2 - Replaced the z-axis coupler with an all aluminum one; the plastic and then the plastic+aluminum one didn't seem to work well for me. This is really the only thing I changed that wasn't in the kit or instructions that I believe made a difference to get acceptable prints.
2) I also didn't use the top plate for the a-axis. Technically the instructions say the z-axis top plate is optional if needed to prevent your z-axis screw from rising up. I figured they sent it, so I just put it on at the start - and I think that was a mistake. I put it on level I am pretty sure - certainly one of the many times I had it off to replace a coupling or otherwise adjust it. I had nice amount of grease/lubrication on the screw cover as instructed - in the end it just seemed to mess my prints up. I removed it completely, so now my z-axis screw is just hanging out there, in the wind, all by itself, and the printer is working so much better.
* - Soooooo what is keeping my y-axis boom arm from wobbling all around? Well, the mount to the stationary metal beam that it actually mounts to I assume... I don't think the z-axis screw is supposed to keep the y-axis from moving around contrary to all the bearing adapters and things that others have added. As from what I said above, the 2 fixed guides and 2 eccentric jobs seem to have a LOT more do with the y-axis moving around than the z-axis screw. They stated the plate was there just to keep the z-axis from rising, not to keep it "steady" or the like, after removing it, I tend to believe them. Not sure doing anything to "steady" the screw it is helping the situation... but everyone's parts and thus builds are probably different, so maybe other builds need those extra stabilizers at the top of the a-axis.
3) ~$35 = 28.50 power supply + $3.50 switch + $3 connectors/14g wire + printed PETG cover/holder - Power Supply replaced with a Meanwell 350W 24v unit. I don't think this is making any difference to the printer. I did this initially to get the heated bed to 110c (at the time I couldn't even set past 45c - but come find out that was a problem in my configuration.h file). Now in the end the power supply isn't a bad investment because I heard so many people say the power supplies that came with it were failing.
With the new larger power supply I also removed the Power MOSFET board and have the heated bed running directly from the mainboard just fine. I don't really need the 110c hot bed though as the magenetic flex sheets (and more importantly the sticker on them) doesn't seem to work for PETG, it sticks WAAAAAAY too well and I ruined a couple of sheets that way. I am not blaming MakerTech3D for this... the fact is you could never heat the bed hot enough for PETG... so, perhaps they didn't think to tell you not to use the stickers if using PETG. Or maybe I'm just doing something wrong. If I ever decide to try PETG again, I'll use some blue painters tape on top I guess or get a piece of glass or something.
4) 0.4mm nozzle tightened while hotend was hot - no idea if the .4mm is making a difference for the MakerTech PLA+ or not (not the original rolls, which I tossed, but I bought some other roles which seem fine)... I might try the 0.3mm again, or I might not. This one is finally working for me, so I'm happy. The one thing MakerTech3D just suggested today on the forums was to tighten it while hot, so that is what I did. Essentially, I pulled the PFTE out, heated the hotend to 215c, tightened the nozzle relatively tightly, then loosened "about 1/2 to 1 turn", then put the PFTE back down, then tightened the nozzle back as tight as it could go without really "over tightening" it. I think it worked fine. This is a cheap $15 hot end from Amazon that looks amazingly like the ones from MakerTech3D, but if I have another meltdown - I'll try theirs that I just ordered. I didn't replace the white tape that was on it, and still no leaks.
And so far no headend meltdowns or encasement of plastic like what happened a couple of weeks ago and "destroyed" my original hot end as it was encased in plastic. So far is this afternoon/tonight with a great XZY Cube, most of a benchy that was printing great up until the roof when I am pretty sure someone moved the bed (though the kids say they didn't, maybe it just broke loose - the brim didn't look great), and now another good looking benchy.
I'm happy. I know so many other folks have struggled. Maybe it is quality control of the parts. The bed seems to be anything but level, I'm just using the 20-point leveling and it varies (no pattern that I can make out) from -0.6'ish to +1.6'ish for me. Printed out a 75x75mm square in the center of the bed, and can clearly see where the northwest quadrant the first lines don't even meet, then as it gets closer and into the southwest quadrant the lines spread and meet and it looks great. I did have good bed adhesion for any PLA+ that was touching; but clearly can't print a solid first layer. I wonder if the bed leveling & fade height is even working... or I just need to do the 90-point leveling method described elsewhere in the forums. Meh. Will just keep trying like it is for now.
Here are some result pictures; prior results are elsewhere here on the forums, though the four benchys together the red was the first print off this printer, the blue was after a few cubes and a couple of other things, then the yellow one is the one from tonight (after the failed benchy due to bad adhesion or a kid moving the table/bed)... the green one is off a factory assembled Prusa i3 MK3S that my wife and kids use mostly.