# Howdy - new A250 Owner. Suggest Start-up Tasks?

**URL:** <https://forum.snapmaker.com/t/howdy-new-a250-owner-suggest-start-up-tasks/8155>\
**Category:** Snapmaker 2.0 (3-in-1)\
**Created:** [August 7, 2020, 5:43pm UTC](https://forum.snapmaker.com/t/howdy-new-a250-owner-suggest-start-up-tasks/8155 "2020-08-07T17:43:21Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![Atom](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.snapmaker.com/atom/32/5608_2.png) [@Atom](https://forum.snapmaker.com/u/Atom)\
**Post date:** [August 7, 2020, 8:04pm UTC](https://forum.snapmaker.com/t/howdy-new-a250-owner-suggest-start-up-tasks/8155/2 "2020-08-07T20:04:41Z")

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@rtrski

> [@rtrski](#):
>
> Calibrate extruder? (Can I do this thru Luban with USB connection? I have a link for a tutorial for the commands and running a 100mm extrusion test.)

yes here is a link to a thread that covers this: [Extruder Calibration a must - #22 by Atom](https://forum.snapmaker.com/t/extruder-calibration-a-must/7724/22)

> [@rtrski](#):
>
> Anyone know what sort of amps this thing draws when heating bed and extruder and printing? I plan to build my own new patch cable into the PSU with a 120VAC current monitor inline, but in the meantime concerned about having both it and my computer (1200W PSU) running simultaneously on a typical US 15A breaker. If not actively printing I’m sure it’s fine.

on the PSU it says input amps is about 4, i would assume a max 5A draw at 120VAC to be safe. that said you should be fine as i have ran my PC (1400W PSU), ender 3, SM2 A350, and other various smaller electronics at the same time on a 15A circuit and have yet to throw a breaker. (not that i would recommend having that much on the same circuit)

> [@rtrski](#):
>
> Benchy or some other first print test.

i would test with the kickstarter test, i find it to be good and it is what all3dp uses to test all the printers they review. it can be found here: [https://github.com/kickstarter/kickstarter-autodesk-3d/tree/master/FDM-protocol](https://github.com/kickstarter/kickstarter-autodesk-3d/tree/master/FDM-protocol)

> [@rtrski](#):
>
> Suggestions for first steps after firmware update?

i would remove the hot end and check for debree (has been a problem for some) and while it is out i would apply some thermal paste to the thermister or the thermister hole for better temp control.

additionaly i would adjust the retraction down (most people on here recommend 1mm) i have found 2mm works well for me. but i have not adjusted my K value yet.

I would also adjust your K value as well if you have time. here is some info on how to do that:

> [@Improving Print Quality](https://forum.snapmaker.com/t/improving-print-quality/6827/13):
>
> "As of this moment it is a slow process to calibrate K value but possible if you have the time to do it. I used the gcode generator at this link to make a test file [https://marlinfw.org/tools/lin\_advance/k-factor.html](https://marlinfw.org/tools/lin_advance/k-factor.html)
> 
> Unfortunately as the SM2.0 currently doesnt respond to M900 Kx.xx commands, you cannot use the gcode generator above to automatically test multiple K values at once. However, it is still useful as a test print. Because of this, it does not matter what k values you set using the generator.
> 
> Once you have the g-code generated, try printing it. This will be done with K0.22 as this is the SM2.0 default. You can evaluate the print performance with reference to the visual guide at this link [https://marlinfw.org/docs/features/lin\_advance.html](https://marlinfw.org/docs/features/lin_advance.html).
> 
> Once you have determined whether you need to increase or decrease your K value from the initial test you will need to change the setting on your printer before running the test again. To do this, connect to the printer over usb. Once connected, type into the command line M503. This brings up the printer saved settings and you should see one of the lines says M900 K0.22.
> 
> To change your K value type into the command line M900 K0.xx (I suggest jumping right to K0.08 as this is what I found was the best setting). Type M500 to save this value. Restart your printer by power cycling and re-connect over USB and type M503 again to double check your new K value has been set. Now re-print the g-code and re-evaluate.
> 
> Rinse and repeat until you are satisfied that you are printing consistent line width!
> 
> Hope this helps."

> [@rtrski](#):
>
> Select a better bed calibration (4x4 or 5x5 recommended?)

i use 4x4 and find it works well enough for me, but that will depend on how flat your build surface is.

> [@rtrski](#):
>
> Luban installed on PC (3.8.0).

if you are familiar with other 3d printing software (cura, simplify3d, etc.) i would recommend using them as the Luban slicer is just about worthless. in fact Luban is probably the worst part about the whole printer (but that may change with time)

good luck, happy making, and let us know if you run into problems (or not 🙂 )  
-Atom

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