Extruder Calibration a must

i think this has been covered already but worth a remention as my A350 shipped with the extruder E value of 212.21 and it needs to be 249.65

This is quite a 15% inaccuracy and results in significant under extrustion. Quite suprising the Snapmaker team didnt catch this in QA testing. Hopefully they will ship future units with an updated E value to save novices a lot of hassle.

Infact id just say change it to my value by connecting via the Serial USB (not WiFi as you wont get the data) Maximise the Console window in the Luban Workspace. Type M500 and note that the M92 line is likely to have E212.21 at the end… Type M92 E249.65 and press enter . Then type M92 and press enter to notice the value has changed to be E249.65 then press M503 to update the firmware and permanently store the new value

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Mine was off by about 11% and i’m at 238.5 ish.

Mine was E212.21 to E238.44
did you messure right @chazr33gtr?

I would double check @chazr33gtr the average tends to be ~10% out.

Agree. Need to change mine as well to 235.79

ill double check as my digital verniers are a little cheap shall we say… but certainly print quality is improved and any last tweaks can be corrected by a few percent on flow rate adjustment in CURA… whereas was miles out before.

Im still not enamoured with the extruder and might customise it to a BMG dual drive one. If I bypass the filament detect switch and solder the wires together so it thinks it permanantley got filament… that would work wouldnt it? Not bothered about filament detect as dont do prints big enough to cosume a 2kg reel in one go.

You could disconnect the switch from the pcb.
I had such an error, that no filament runout was detected, because of a loosened plug.

Sorry for the simple question, but where do a find instructions how to measure and change the e-value. Best, Johannes

Basically any you tube guide on tuning you extruder e-steps with give you the principle. My instructions at beginnning of post are how to correct the value (once calculated) in the Snapmaker firmware.

In simple terms. mark the filament 100mm from the enterance with marker or cut it with snips at that point. The heat the snapmaker print head up and send Gcode G1 E100 F300 this will extrude what the electronics think is 100mm. Measure the amount of filament left sticking above entrance of extruder.

Then a bit of maths that has been optimised for quickness
E step error = 100/(100 - bit left) (e.g. 100mm and you 9mm left then it would be (100/100-9) = 1.098
New Extruder E valuein firmware = oldvalue* E step Error (e.g. 212.21 x 1.098 = 233

Above values are jsut used as an example… just replace them with your measure values then follow the steps to change the firmware at the top of this post

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Great. Thank you for the advice! Best, Johannes

I think you have messed up the M500 and M503 code.

M503: Report Settings
M500: Save Settings

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good spot… i cant seem to alter the original post now tho :frowning:

Mine was off 14mm. Changed from 212.21 to 246.75. Ran test again and still off a couple mm’s. How accurate are we trying to be?

Also, I’m assuming we do this once and then don’t really have to worry about it? Am I correct in assuming it’s independent of what type of filament we’re using?
Thanks!
-Steve

Yes and no.

Generally you shouldnt have to change this but it depends on how accurate you want to be. Depending on what material you are using and their individual hardness/softness, very slightly different amounts can be fed due to the extruder gear “pressing” deeper or shallower into different materials. For example, soft materials like TPU might be pressed into the gear more and result in slightly less extrusion but its all marginal.

i knew there was something up with the E steps!, i mentioned it on the Kickstarter comments and people acted like i was crazy… anyone else annoyed that this is so far off out of the box?

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Not annoyed really no as e-step calibration is something you should perform on any new printer. This however does assume that you have owned a 3D printer before and know that e-step calibration is a useful thing to do out of the box!

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I ran the test made the first time did the adjustment reran and got exactly the same amount left over. My system was off by +10 MM each time. I double checked that the new estep was the same as what I calibrated it to any advice?

Have you saved correctly with M500 (connected with USB-cable) ?

M503; read the current settings
M92 Exxx.xx; set the new E-stepper value
M500; save settings
M503; check if new settings were saved

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new settings were saved and second test was run with new settings with the same result +10 mm of filament left over