Micromake connection and leveling troubles

Been itching to get a 3D printer for ages, and finally got a new Micromake for myself for the holidays. Got it all assembled okay, but I seem to have a few... Issues, preventing printing properly.

Firstly, USB connection: It connects, Cura seems to work properly at least on the surface, but Repetier-Host and Repetier-Server throw a fit, filling the error log with things like "Error: Wrong checksum" "Resend: 1" and "Unknown command: Z0.00 I0.00". Googling didn't get me much info, but I suspect it's a baud rate issue, since it's set to 256000. I'd like to set it to something more sane like 115200 or something, but the problem is, every time the machine reboots, it always goes back to 256000 even if I select "Save to EEPROM" after changing it - and it reboots every time USB is connected or Repetier-Host/Server tries to access it, so I've yet to successfully connect at 115200 before it ends up rebooting and going back to 256000. So at present Repetier-Host and Server are useless with it, but Cura can at least connect in some respects - auto-level sorta works, printing over USB sorta works, and I don't get any errors, but suspiciously the bed leveling wizard won't go past "Connecting to machine..." - again, I suspect baud rate shenanigans that I can't correct without making changed baud rates stick.

Second, the reason I say auto-level and printing "sorta" work: I can print! Kind of. If I print something small near the center of the plate, it behaves normally, though things tend to unstick and fall over before it can finish... though that's probably because the power supply I have sucks, and I only have a spool of ABS, so I'm currently printing ABS with no heated bed which I'm well aware is bad. But that's not the problem. The problem is, the closer the nozzle goes to the "X" side (as identified by the leveling model) the more the head smushes the filament into the plate until it's pressed so close nothing comes out and it ends up spitting it all out as a blob when the pressure is released elsewhere. And the closer it goes to "Z", it seems to be lifting up just enough to not have the filament adhere properly. The letter "Y" shows both, since it's flattened on one side of the Y and unstuck on the other side. I suspect an uneven build plate, but autolevel isn't correcting for it despite a tolerance of 0.1mm and due to the aforementioned probably-baud-issues the bed leveling wizard won't help me.

TL;DR: Baud rate stuck at 256000, can't lower because it goes back to 256000 on reset and won't save. Auto-level not quite right because the sensor doesn't always click easily despite making it as sensitive as possible without it getting stuck open. Auto-level system at least sorta works, but bed leveling wizard doesn't due to connection issue.

Edited 1 time(s). Last edit at 12/30/2016 06:20PM by Jaitsu.

Update: Well, I found one major source of issues. My power supply wasn't bad, I just needed to flip a 110/220V switch that was -inside- the unremovable housing with no indication of its presence. Had to stick a toothpick through one of the cooling holes to flip it. Now it at least heats the bed to 100 C (won't quite hit 110, I may need to tighten the power contacts), and connects properly at 250000 baud, at least to Repetier Server - Cura's bed leveling wizard still won't work. But I have more issues, it seems. After seemingly leveling the bed and starting a print, I got a good, even first layer on a print... then halfway through the second/third layer, it does a z-hop and the head comes back down way too low, digs through the first layer, crashes into the build platter, retracts, and starts trying to print the rest in the air with the effector moving diagonally upward through the air. And it keeps doing that for every print at some point or other.

Hi Jaitsu,

Your stepper motor current might be too high or too low. Either one can cause this sort of issue. Try setting the voltage on the pot to around 0.45 volts, this is a nice safe current for most stepper drivers.

Well, because of the design of this thing, the board is covered with plastic except for the connection points and I can't remove the cover without completely disassembling the printer. But I did take a multimeter to the power adapter, and found out that while I have the input voltage (110V) right, now the output voltage was wrong (13.8V instead of 12V). I adjusted that down to 12V. Printing a small part right now and so far so good as far as not spontaneously jumping down, but now I'm starting to realize something else: I don't think it's moving as far up as it thinks it is each time, because models are coming out shorter than they should along the Z axis and I keep hearing the Z-probe switch clicking like the nozzle's not moving up enough to not be pressing down on the previous layer. Is there a setting of some sort to correct that?

Edit: Well, scratch that. Same deal. Halfway in, nozzle abruptly digs into the print, gets stuck, pulls back and starts going on a diagonal in the air. Maybe I will take it apart to get at those test points and pots. The motors aren't making any unusual noises, no ticking or anything, and X/Y movements seem fine, but Z movements seem to have a good chance of throwing it off. Either way, couldn't hurt to take a look... hell, I have half a mind to drill out some holes in the plastic housing for easier access to things in the future.

Edit edit: Maybe it's a firmware thing with Z-hops or something? I turned down the Z-hop height to 0.2mm (I had it at 1.5mm then 0.7mm because I got annoyed with the nozzle bumping things before I figured out how to properly autolevel) and it stopped doing that, also adjusted the Z-probe to make it more sensitive and tweaked first-layer extrusion, successfully printed some small parts. I may need to check if my glass build plate is perfectly level, because unless it's convex/concave or something I really can't explain the leveling weirdness I'm still seeing, it seems to get worse further from center.

Edited 3 time(s). Last edit at 01/02/2017 09:01PM by Jaitsu.

Ah ha, that's making a lot more sense now.

Your steps per mm are probably wrong, probably by a lot. What you're seeing is probably massive overextrusion due to the nozzle not going up high enough on each layer.

Here's how to diagnose it:

1) Home the printer.
2) Measure the distance that a carriage moves, when you manually move the nozzle 50mm downwards. If the problem is what I think it is, then you'll be able to easily measure the problem with a ruler. If you want to get fancy you can use a set of calipers, but it seems like you're way off.

If the carriages are not moving the right amount, then you need to change your steps per mm value. You can calculate this with the number of teeth on the motor pulley, the motor steps per full revolution, and the size of the belt. It will probably be a whole value like 80, 100, 160, or 200.

Note that this will also affect your Z height, and if you're not careful after changing the steps per mm then you'll end up with a massive head crash... so go easy, take it slow, and do a full recalibration.

It's currently (somewhat successfully!) printing out another test model, if still somewhat squished, but I'll take a look at those when I'm done and edit this post if I get said numbers before you reply again. Can you elaborate a bit on what I need to do with those numbers (teeth on pulley, steps per revolution, belt size)? Sorry if I seem a bit... clueless, the instructions this thing came with were a bit unclear at best and this is (probably obviously) my first printer.

Heck, I just hope I've got these belts set up properly at all. I mean, it works. I tried to make them 'reasonably' tight, but that's guesstimating at best; all I can say for sure is that they're tight enough to have some actual tension but not tight enough that I think they're restricting the movement of the motor.

Edit: Actually, I just measured, and at least heightwise, 50mm is 50mm according to both a ruler and the LCD. I'm really thinking something is up with how it handles z-hops ("Z hop per retraction" in Cura), because the lower I set that, the less squished my models are and the less likely they are to fail. With Z hop set to 0.2mm I just printed a model almost perfectly (except in my impatience to take it off the build plate it split, oops) aside from stringing and bad supports, but I think that's a retraction issue. Re: teeth on the motor pulley, that's... harder to find out than I thought it'd be without dismantling the thing, but that might not be my issue anyway, it seems. I'm still probably gonna open it up and check the voltages to the motors (since I suspect the issue with Z-hops is being caused by missed steps) but for the time being setting z-hops to not-crazy values seems to be at least a partial fix! I printed a dog.

Edited 2 time(s). Last edit at 01/02/2017 11:29PM by Jaitsu.

OK then, that's not the problem. Disregard my post.

I use a Z hop of 0.4mm, that seems to work well.

Good luck with your setup. You'll get there.

Still, thank you very much for the advice! I'm totally new to all of this, so any help getting it working is appreciated. Still just chipping away at little fixes inching toward getting it working... right now I think my two big obstacles are Z-probe accuracy (because the effector likes to wobble slightly before it triggers and throw off the calibration, despite the effector being nice and stable otherwise and the probe being as sensitive as I can make it without it getting stuck open) and possible missed steps, which I'd bet you're right about re: voltages. I just opened it up and tested the voltages - got 0.608V on the X motor, 0.628V on Y, 0.658V on Z, and 0.772V on the extruder motor. That's... bad, I'm guessing.

The effector motors' model numbers (Micromake branding) are 17HS1538-P4130 and the extruder motor, which is actually bigger, is 17HS1910-P4130, if that helps, but all the datasheets I've found are in other languages. Here's something, at least: [i.imgur.com]

Edit: ...wait a second, that sheet is for the p4170. And I notice a correlation between current and that P-number, so it'd make sense for P4130 to expect 1.3A, so... 0.65V tops, probably better to go a bit lower. Right?

Edited 2 time(s). Last edit at 01/03/2017 08:59PM by Jaitsu.

That sounds like a slicer issue, not a machine issue if your steps per mm are ok. Forget z hop and fancy stuff for now. Enable display travel moves in your slicer and flip through the layers to see if your machine is merely doing what it's asked.

So! I think the board is toast. Turned the pot a tiny bit, measured again, now it's getting 0.1V. Okay! Turned it too far. Turned it back. 0.1V. Ozone smell, display dimmed a little. Um. Kept turning both ways. 0.1V. Motor won't turn either. Perfect. Wonderful. Well, then. 'Least a new board is only 30 bucks if need be. Do we have a hall of shame for noobs that toast their boards?

I'm gonna keep fiddling with it for a bit, mind you, since I don't SEE anything that looks bad, buuut after the display flicker and the smell, I'm gonna kinda figure I let the magic smoke out.

To answer clearlynotstefan: I checked, nothing looks strange in layer/travel view (I'm using Cura.) Horizontal lines, the printer was just abruptly going off the rails and printing diagonally. Well! Perhaps the new board I'm probably going to have to order will come better adjusted because I've acquired a bit of a fear of touching circuit boards.

Edited 2 time(s). Last edit at 01/04/2017 07:49AM by Jaitsu.

Righto! I'm back, with a new board and a healthy fear of fiddling with circuit boards without taking proper precautions. Bought a new board for the thing, put 'er back together, and... What do you know. After making some quick adjustments (default Z height is way off) I was *immediately* able to print out something vastly better than I ever managed before, on the second attempt (first was too low and squished the first layer, I think I need to fiddle with the z-probe 'distance' settings). I suspect it really was a badly-tuned board, but I'm not touching that thing with a multimeter while it's on 'til I have something to protect the surrounding components/board with.

Edit: Oh, to be fair, I am still hearing clicks from the Z-probe switch as it prints, but the print comes out fine, so I'm not quite sure what's going on there.

Edit 2: I think I'm on to something. It may be over-extruding. I noticed that with some prints, the hot end is being gradually pushed up by each layer (since it's on a hinge for z-probing) and thus gets gradually worse as it's pushed up higher, because layers are being printed too thick. The lower I set the extrusion (presently doing so by reporting 1.75mm filament as 1.9mm), the less issues I seem to have. It wasn't actually suddenly diving into the print, it's hitting a point where the hot end can't be forced any higher up to compensate for the excess thickness of lower layers, then it eventually needs to do a hop, the hop puts it so low that the hinge can't accommodate it, then it gets stuck, which makes a motor miss steps, which throws off the angle and causes all the aforementioned symptoms. Progress! (Have I mentioned the concept of having a movable nozzle for Z-probing is a really dumb idea?)

Edited 2 time(s). Last edit at 01/21/2017 09:11PM by Jaitsu.