new A20M couple of problems

[ermockler]

Hi,
I got my A20M about a week ago from amazon, Everything worked great initially.
Suddenly it no longer detects the SD card. Tried 3 or 4 that I have here and nothing.
So I've been using Octoprint with a raspi 3b+. Not as good results a from the sd but ok.

Now the button no longer works at the panel, I hear it click, but nothing. Of course I pwr cycled & press the little reset button.
I was thinking just now maybe it disables this stuff while plugged into usb? I have other printers and they don't do this.

So I would guess my next step is to disassemble it & check connections? This all was pre-assembled, so if they're loose they cam this way.
Or maybe I need another LCD board? They seem cheap enough, but I shouldn't have to be buying replacement parts for a 1 week old printer.

If there any tips for getting octoprint working better in the meantime that would help. Or can I run Eazyprint on a PI?

The other little problem I have is the #2 extruder pumps out alot less than the #1. I took apart the mech and tightened it up some, and cranked up the flow on that side to workaround. 150%. They still don't seem equivalent, but closer.

Otherwise I'm very happy with the quality, much better than my other machines.

Thanks for the help!
Eric

[ermockler]

I fixed the button

[ermockler]

Thanks,
I also kind of fixed the SD card, I have to boot with it in now. Must be some broken switch that detects it's inserted, but I guess it checks upon boot too.

But it's still underextruding bad on the right #2 side. Where would these jumpers be? Hopefully not inside the base bc it's a real pain in the ass getting in there.

[ermockler]

I swapped the wires around between the extruders, so the right one is now ext#0 and left is ext#1. Same one still under extruding. So i would say that eliminates everything inside the base. I'll try cleaning out the hotend some and maybe have to bevel off a tube in there or something. I already tried tightening the spring tension previously.

[sunret]

Hi All,

I'm having a similar problem (underextrusion on one of the filaments); and also after about 2 weeks of use.

I've swapped filaments -- problem stays with the extruder, not the filament.
I've swapped bowden tubes at the output of the extruders (so they go to different hot-end inputs) -- problem stays with the extruder
Thanks to ermockler for the idea -- I've swapped the driver connector wires -- problem stays with the physical extruder

I think this eliminates hot-end issues, bowden tubes, driver electronics, cura code, and leaves only the extruder itself.
At one point I had the hot-end uncoupled from the bowden tubes, and I ran an extrusion test (so there was no back pressure) and got exactly what I expected for extruding (and then retracting) 100mm. Yeah ... we already know the problem isn't backpressure in the hot-end since the same hot-end input is fine with the other extruder, but this also implies that the faulty extruder is working fine under no-load conditions.

I've adjusted the spring tension in several different ways and nothing helps ... although some settings can make things worse!

I'm also noticing a fair amount of "filament dust" on the failing extruder (but not on the other one).

I had a similar problem after about 6 months ago with my Ender 3 (of course, it only has one extruder and hot-end). There the problem was obvious when I took the extruder apart, and the solution was the vendor's own extruder upgrade kit.

In this case, unfortunately, the equivalent Geeetech extruder kit is not available on Amazon, and I can't find it on ebay either ...

Any other thoughts? Cuz I'm not past the Amazon return limit date, yet; and I'm thinking of returning it.

Thanks in advance

[William]

Hi, You can provide your country,
Order number, email,
Will give you the corresponding extruder upgrade kit.

I hope this can help you.

[sunret]

I took the ill-behaving extruder apart; and in my case, I definitely have a crack on the lever arm. - Jay

[Jarda3d]

Extruder lever is very weak part on all Ax0M printers. Print your own with second extruder, but you need filament blocked in bad extruder otherwise you block extruder.

[sunret]

Thanks for that tip on plugging the bad extruder. I see you recommended printing the extruder levers and replacing the factory ones in a previous thread. But I didn't see ...

Do you have a favorite STL you could recommend for this part?

Thanks

[Jarda3d]

I was print 4 different and at one made very hard after-print customizations of lever and extruder anti-jamming nozzle to fit. Before few weeks I was see some new, but not print because mine are still good (ABS).

https://www.thingiverse.com/thing:4084312
https://www.thingiverse.com/thing:3456879
https://www.thingiverse.com/thing:3383435

In attachment is slightly modified lever in my second extruder. With this and playing around, your printer will print again, but it is bad because you need modify your extruder. (gcode only stl is too big).

Cutted idler version is not printed now and is modified from which I was print it and made cuts. And finally, there are license problems, I dont know from which source I vas get it...

Print it with healthy extruder using mixer and leave note, please.