Bed Leveling Every Print.

Crasoum

Is it normal to need to adjust the bed level every print, or every other print? 

I am not sure what it is, as I've double checked the screws for the Z axis and the Z-home switch. I have adjusted the springs to be as tight as possible while still allowing some adjustment for tuning.

I've also moved both the z-axis motor and the switch down a smidge so I barely have any travel to adjust with and after every couple of prints I can slide my feeler gauge under the hot nozzle and bed. I'm using a .08 mm gauge where I adjust it until I can't slide the gauge under the nozzle with maybe a 30 degree turn of the wheel (so 1/12th a turn, not a lot but just enough).

I have been doing this on a hot bed and hot nozzle so thermal expansion isn't my issue up top.

I've had the printer a week, and can't find a terrible lot about things like this, but from looking on youtube about ender 3 printers, looks like a spring replacement would be the next step. Is this correct?

Stephen Todd

I packed the bed springs on my A3s with washers to make the bed more solid with less give - just enough to move down should the nozzle hit the bed

I then set up mesh bed levelling - no problems since then

You can print "bed spring guides" from thingyverse - supposed to improve things
https://www.thingiverse.com/thing:2769200

Edit: There are two versions, depending on how much you want to compress the springs - but you only fit them to the bottom of the springs - the nut holds the top of the springs in place

Crasoum

Yea my problem isn't that the bed is warped, it's pretty level actually. When I first level it.

Once I print an item or two after that my print's (lack of) adhesion causes the print to fail so when I go to retest the gap I end up with a .12* gap or higher. The washer trick might be a good stopgap though, so thanks for that!

Oh cool I missed the spring guide comment, I'll try that too.

Stephen Todd

As you have a removable "mat" to print on, I'd simply buy a good quality (not fake) 1mm or 2mm rigid PEI sheet - people who have them say they are brilliant

I myself have the notorious black diamond "non-stick" surface - I sanded it down to a matt finish, and roller on heavily diluted PVA wood/fabric adhesive, 3 parts water, 1 part adhesive - can't get the prints off now until left for a few hours to go cold - not sure if it will work on your PVC sheet though

Crasoum

I switched to a glass print bed after almost immediately destroying the build mat trying to get an ABS print off it and cleaning it with acetone. Sooooooo I won't be doing that again. 

Note to others, don't use acetone on the build mat. I'm sure more advanced users would say duh, but I was following guidance that acetone slurry helps prints stick, and so I figured I'd try that after having prints lift after the 2nd or third print on the mat.

Then they lifted off the glass bed.

Then the searching to figure out if it was just me, or the springs. It could still be me, but I'll blame the springs currently. 

Laser8302

ABS will curl when printing in open air. Even in an enclosure it doesn't print perfectly due to the amount of shrink.

Read here for suggestions on how to succeed with ABS:
https://www.simplify3d.com/support/materials-guide/abs/

Crasoum

I made an enclosure, my prints aren't curling (much except around the X on a calibration cube, which I think is just a cooling issue where the nozzle is melting nearby layers) they are flat out failing because they end up as tiny ropes across the bed and never adhere, fall over mid-print, or they detach from the bed.

I appreciate the link, I've done a ton of reading and watching and have successfully printed with ABS a dozen or so prints. I actually used that site for a lot of reading.

 As long as I sit and watch the first layer to make sure it actually attaches and gets squished to my glass the prints run fine. My issue is after a print or two, I can slip a thicker feeler gauge past my nozzle and when that happens my print has a higher likelihood of lifting off the bed and being carried around by the nozzle in a giant blob. 

It's funny, I've cranked the speed up to 200mm/s and made successful prints, as long as I baby that first layer. But even if I print at 20mm/s after the 2nd or 3rd print they end up roping around the bottom brim/layer then getting knocked over/start becoming a spaghetti mess. 

But I printed spring guides and installed them about 30 minutes ago and am running some test prints to see how that helps me. The springs are tighter, so that's something 

So far, after getting started I have:
Calibrated X and Y steps off a couple of 150mm prints, Z axis was fine.
Calibrated E-Step. 
Calibrated  PID.
Printed about 10 temperature towers, half successfully.
and finally I have messed with Cura to build a profile to print some functional prints faster and faster until I hit 200mm/s in settings (not sure if it printed that fast, but it is set to.) Currently running a 20 mm/s print to test the springs then I'll do an 80 and 200. 

Messing around with it, it works well minus the bed level never staying put, and some light curling around my X/Y text on a calibration cube. ( https://www.dropbox.com/s/o1y7432d9bow2br/2020-03-17 18.44.16.jpg?dl=0 the X https://www.dropbox.com/s/ff71c98w7xq2lfx/2020-03-17 18.44.26.jpg?dl=0 the Y https://www.dropbox.com/s/h7n7x0a6gziiltw/2020-03-17 18.44.30.jpg?dl=0 the Z) The curling got better when I put the fan on 25% cooling (I can't seem to get it to actually spin sooner than 25%) but the X definitely has curling. But for the prints I'm doing it doesn't affect them any, they are simple geometry prints. 

Oh and I haven't dialed in bridging yet, that's on my checklist but I haven't spent enough time getting there yet. 

Crasoum

The 80 mm/s print lifted and testing the bed level it was off again, even with the spring guides and the knobs tightened as much as I could and keeping the bed level for the first print. The 20 mm/s print was fine, and using the feeler gauge after the 2nd print bodged I had a .12* gap. Looks like new springtime (or I just always have to level between prints.) 

Stephen Todd

Having had a think about this, I now suspect that it isn't the bed, but the gantry that is the problem

I have A3s, and once I sorted out the bed spring compression with packing washers, I had no more problems - but the gantry is solid, having a rigid frame holding everything in place

I'd be looking at the possibility that the gantry can be jogged up and down by hand (play), or the nozzle is not consistantly lowering to the same exact height

Crasoum

Yeap the bed guides and what they connect to have some spring, so you're likely right with the gantry I noticed that last night as I was messing around but didn't give it any mind thinking to myself "as long as it springs back to where it was it shouldn't affect my prints." So... new thing to look at. 

I marked on the guide rod where the nozzle usually stops, and the opposite aluminum rail and the nozzle stops reliably in the same spot after it hits it endstop switch. I've made sure all my top end hardware is torqued. I haven't used a in/lb torque wrench but I would place most the screws between 20-70 inch pounds, depending on the size. You know, tight until not moving without breaking the hole threads, or bolts. Looks like I'll flip it over and take a peek under the skirts to see where I can take out slop. 

Stephen Todd

Maybe a digital caliper measuring between bed and heat block will be required to see if z-axis stops at same height each time - maybe send gantry up and down 100mm or more a few times to see

I have read complaints of people with ender 3, which is the same design, complain about lack of z-axis accuracy/play with the design - I would never buy that style of printer

A3s has its design flaws, but it is rigid, and the nozzle lands in the same place each time

Crasoum

I'll give it a few shots, so far I'm resigned to level with every print.

It prints fine after baby sitting, experimenting with it today I can get it to zoom and print "OK" at up to 200mm/s

100 it prints great. But even at the slowest print (unless it's a VERY simple print) I need to relevel.

It can print like crap at 300 mm/s but that was more of a I wonder if...

You say it has the same design as the ender 3, would you say I could pop a Petsfang bullseye on it? I planned on printing one anyways to check, but if you know it'll work I can get started on it sooner before I work on some bridging. 

Stephen Todd

I'd look on thingyverse for any ender 3 improvement parts you can print

I've always suspected the design, and not taken any interest in any printer with that same design - I was suspicious the very first time I saw it

I'd also look out for any third party components sold online to improve the mechanics of Ender 3 and its clones

It may be worth looking at ender 3 facebook groups to see what people are doing to improve their ender 3 printers

Stephen Todd

It seems the standard advice with Ender 3 is fit stronger springs and don't even try and remove a print when build surface is attached to printer - use a removable build surface, and remove the print when the surface is off the printer

Crasoum

Well the carrier for the hotend is different from the E3, so unless I take out the X axis carrier and replace it with an ender one I'll need to mock up an adapted bullseye.  Or mock up a similar fantype that connects to the blower fan, since both fans look to be smaller than ender ones. Plus I'd need to make an adapter to move the wiring harness and the x-stop. Fun fun. 

Taking the plate off and putting it back on helps, but I still need to level between a few prints. Just is how it is for me it seems until I get new springs.

Stephen Todd

The 30mm part cooling fan fitted to AGAurora printers are totally inadequate - I have an additional 40mm fan and duct blowing from the front - only way I could get good prints - 30mm rear fan has 3 way cooling duct, and front fan has single fan duct providing most of the cooling

24 volt power supply is something JGAurora got right, but the original A3s power supply was under rated and burnt out in days, so I got a higher current rating one, and no problems with maintaining temperatures now

Laser8302

What's your first layer thickness set to? I usually use 0.22 to 0.27mm to account for the bed. (That, and I also use a BL touch clone with UBL and probe 3 points before each print.) I still have to babystep the first layer a bit each print. I always watch the first layer go down. It's no big deal but if you have one corner getting messed up, it's either the way you are removing your parts from your bed or possibly your X-axis tilting. Also check your Z motor couplers to make sure they aren't stretched.

Crasoum

Yea the way I was taking the prints off didn't help any, but the springs and screws just aren't good for keeping tight too, so it's a compounded issue of me scraping my prints off the bed on the printer, as well as just the motion of me beating it with high speed prints to see what could be done. 

I've since printed all day without having to level  other then some babying on the first layer. I slowed down to 40mm/s and 80mm/s 

Yea I see the fans are.... Puny. Right now I'm checking out some A3/A5 shrouds to see if they fit, the OG A3 (I think, I can't find the thingaverse print now) doesn't but the dimensions are a good start for me to hack on if the A5 doesn't fit. I'll likely order bigger fans soon, unless I have some 24v in my junk box, which I might now that I think of it. But then I have to make fan mounts, and if I'm doing that I might as well give the mouse a cookie... Which is to say I would likely give myself plenty to hack on. 

Crasoum

I took off the rubber o-rings for my Z-axis, at the suggestion of some youtube videos I watched, it doesn't seem to have changed much here or there. I also lubed all the rods with superlube, but that's more to keep things from binding.  But the coupler seems fine too, but I'll take a closer look later if I happen to get more failed prints. 

Crasoum

So I spent a couple hours and managed to mock up a replacement shroud, but it's way too close to the heating element and the hot end, so I'll have to change the dimensions slightly, but it fits which was the hardest thing to mock up, as the Magic has a completely different fan shroud then the other JGAurora/JGMaker printers. 

Also printing all day I tried to adjust my bed for my last print and I couldn't, so I went looking under the bed and one of the nuts had worked its way mid spring. So yea it's a spring thing, or a nut thing. Or both. 

Stephen Todd

I forgot to say I double nutted the nuts that are under the bed - I do it with anything that vibrates - simply get extra nuts and screw them on tight - stops the original nut working loose - but you could use lock washers under the original nuts instead - there is also "loctite", but I never use the stuff

Crasoum

Yea I honestly thought about double nutting the first time I found problems, but wanted to experiment. I guess my hypothesis was right. 

That or gnomes are trying to sabotage my 3d prints. 

Crasoum

So yea the nuts were the issue. Tightening them up helped a lot, double nutting them made it so the bed stayed as level as it was ever going to be. 

With how the clips are the areas not clipped are a little higher than the areas clipped, but if I put clips near the bottom the extruder rams over them. But I imagine mesh leveling would fix this issue when I get around to it. 

https://www.thingiverse.com/thing:4252819 is the shroud if anyone needs one. I don't know if it works better than stock. I do know on my machine the air hits just below the nozzle like it should, and it hits from both angles fine. My prints seem to come out better, but then again it could be selection bias. 

Crasoum

Sides bolts came loose with all my futzing and made me start going mad too, so tighten those up too if someone else comes across this problem in the future. The bolts that hold the Z-axis aluminum extrusions.