I’ve been having some issues with my Velleman K8200. It was working perfectly with Marlin until the firmware became corrupted. I’ve since installed Repetier Firmware and have everything working except for:
- the Z axis homing direction is incorrect (moves up when it should move down)
- triggering the Z axis end stop does not stop the motor
I’m certain all of the parts function and are wired up, as it was working with Marlin and I’ve been very careful to not change anything. I have sought help in another post here: http://forum.velleman.eu/viewtopic.php?f=50&t=15230&p=70757#p70757 and have fixed everything else that was refusing to work.
Here’s the details:
K8200 seems pretty standard hardware-wise
Has Arduino Mega 2560 and RAMPS boards installed
Has Repetier Firmware v0.92, controlled by Repetier Host v1.54 on Windows
All other manual controls except the ones listed above are working as they should.
Can you please check your printer shape settings?
These are the settings for the stock K8200 with marlin.
[quote=“ichbinsnur”]Can you please check your printer shape settings?
These are the settings for the stock K8200 with marlin.
[/quote]
I can confirm Repetier Host printer shape is 200x200x200 print area, printer type is Classic and XYZ homes are all set to Min.
[quote=“dislegal”][quote=“ichbinsnur”]Can you please check your printer shape settings?
These are the settings for the stock K8200 with marlin.
[/quote]
I can confirm Repetier Host printer shape is 200x200x200 print area, printer type is Classic and XYZ homes are all set to Min.[/quote]
Can it be “invert direction controls” is checked for Z on the printer tab?
[quote=“ichbinsnur”][quote=“dislegal”][quote=“ichbinsnur”]Can you please check your printer shape settings?
These are the settings for the stock K8200 with marlin.
[/quote]
I can confirm Repetier Host printer shape is 200x200x200 print area, printer type is Classic and XYZ homes are all set to Min.[/quote]
Can it be “invert direction controls” is checked for Z on the printer tab?[/quote]
Nope, invert directions for XYZ are all unchecked as well.
Hmm, i don’t know the repetier firmware by now.
Did you compile it yourself?
If so, maybe there are some settings to tweak in the firmware files for use with the Mega and Ramps.
Pin numbers for the endstops or axis settings for example.
I think we’re onto something here!
So using the M119 command, and plugging and unplugging the endstop wires from the board, I can see that X and Y are responding correctly.
X and Y both show value “H” when the endstop is hit, and when I disconnect it, but when it’s connected and not hit, it shows value “L”.
Whereas Z shows value “H” all the time, whether it’s hit, not-hit, connected or disconnected.
As far as I can tell, it seems to occur no matter where X and Y are currently. So would I be right in assuming I have to figure out where my problem with the Z endstop is? I’m guessing I’ve got 3 possibilities - 1. it’s connected to the wrong pins on the board, 2. the switch itself is faulty, 3. there’s a problem with the wiring between the switch and the board.
What should I check first, and how do I go about it?
Ah, that sounds like an endstop wiring issue.
From your writing i assume (compared the x/y endstops) the switch is normally closed, thus
whne the endstop is hit it opens the circuit. This will detect broken wires also.
I would try to disconnect the z endstop plugs from the board
and measure for continuity with a multimeter.
start at the pins of the endstop switch first.
So, if the switch shows changing continuity if pressed or unpressed it should be ok.
Then its a wiring fault. (broken wire/ bad solder joint …)
If the switch is not ok, simply replace it.
[quote=“ichbinsnur”]Ah, that sounds like an endstop wiring issue.
From your writing i assume (compared the x/y endstops) the switch is normally closed, thus
whne the endstop is hit it opens the circuit. This will detect broken wires also.
I would try to disconnect the z endstop plugs from the board
and measure for continuity with a multimeter.
start at the pins of the endstop switch first.
So, if the switch shows changing continuity if pressed or unpressed it should be ok.
Then its a wiring fault. (broken wire/ bad solder joint …)
If the switch is not ok, simply replace it.[/quote]
Excellent! Followed your steps, found a continuity issue in the Z endstop wiring, resoldered all of the connections in the circuit and it roared into life!!! Woohoo!
Thank you all for the help in solving this!!!
I fired it up to print a test cube and found it’s printing askew (as in each layer on the Z axis it builds up has moved over to the right and back a little, so it’s crooked). In any case, now that it’s working again, I figure the rest is just tweaks, so I’ll have a crack at that another day. Thank you all again! 
Nice to hear!
Happy printing!
