Board connections mixed up

[chrisnasulea]

Hi,

I recently bought one of your dual extruder DIY printer kits from ebay. I finished assembling it and wired everything up. I followed the instructions rigorously but I find that some things are not working as expected.

For example:
Sending the extruder 1 heating command from Repetier Host actually heats the heat bed and vice versa.
The Z axis motors do not respond to commands.
The X axis only works in one direction.

The Y axis is the only one that seems to operate normally, though the motion may be reversed.
Also, extruder 2 is operating normally and holds temperature well.

The instruction booklet that came with the printer said I should download the full building instructions from this address:
https://www.geeetech.com/geeetech-unass ... p-927.html

I can probably figure out which wires to switch myself but I was wondering if there's something I may have missed that will make my life easier.

Please help!
Thank you!

P.S. P.S. It would have been handy to include some instructions in the package about software configuration (like the communication speed of the board) required to control the unit from Repetier or other software.

[William]

I think you should attach the wires of the photos.
We will check it

[chrisnasulea]

I solved the first part myself. The extruders and heatbed now heat up correctly. I had indeed made a mistake and reversed the thermistors for extruder 1 and the heat bed.

I am now checking motors for axes X and Z to make sure they work and I will then send you some pictures.

[chrisnasulea]

Currently the printer still exhibits the following abnormal behaviour:
1. X axis will only travel to the left (-). When I send a command to move right (+) from Repetier the motor seems to try to move but it is unsuccessful.
2. Z axis will not travel in either direction. The same thing, the motors vibrate, they try to move but it does not work.

I have attached a photo of my wiring.

Since my Y axis works normally, I have plugged each motor into the Y axis connector to make sure they work. They all do!

So, what could it be?
Maybe the drivers?
The firmware?

[chrisnasulea]

So, I ran more tests. I moved the drivers around. It seems only the Y axis driver works properly.

The other 4 drivers (X,Z, Extruder 1, Extruder 2) have issues. 3 don't work at all. The 4th one sometimes works and sometimes only turns the motor in one direction.

What can I do to get my long-awaited Geeetech printer up and running?

[_kaktus_]

Hello.


In this case you need new stepstick modules.
Try to analyze what could have caused this state of affairs.

[chrisnasulea]

Well, unless there is an issue with the PSU, I can only imagine the drivers were faulty when they arrived.

Can you think of other possibilities?

Also, can you confirm that the drivers were in fact Stepstick A4988? I can get these locally faster than it would take for you to send them.

[_kaktus_]

Hi.


After the appearance of the modules from the photo I guess that they are A4988.
If you want to be 100% sure, peel off the heat sink, then you will be able to read the marking from the chip.

One fact drew my attention.
On the photo you can see that the heat sinks are very nearby the module leads.
It is worth checking if there is a short circuit in this place.

In my opinion, it is very unlikely that the stepstick modules were factory damaged.

I have one more proposal.
It is worth checking if the order of wires is identical in each of the cables connecting the stepper motor.

[chrisnasulea]

Your solution gave me hope! I really thought "maybe I made a mistake! maybe I shorted the stepsticks and that's why it doesn't work!".

Nope!

I just spent two more hours checking things. The stepsticks all had some of that adhesive paper in between the heatsink and the leads. I moved them further away from the leads and the printer still doesn't work properly.

I also checked the colour sequence on the cables connecting the motors to the board and it is the same for every cable. They are also connected the right way to both motor and board. Unless there's some internal damage under the mesh of those cables, where I can't see, they are not the ones to blame. Also, if I move my one functional stepstick to a new position, that motor starts to function normally.

On Tuesday at noon I get 5 brand new stepsticks in the mail. I guess we'll see what happens then!

[chrisnasulea]

I have replaced all stepsticks and the motors now operate normally.

Kind of!

I think I might now have a mechanical problem. I have never had this happen with any of my previous 3D printers.

The left Z-axis motor seems to get stuck. It's like the 2 axes aren't parallel and it's struggling to turn the threaded rod.

Here is a YouTube video of the problem:
https://youtu.be/AlDCrKJOgwo

Any ideas?