Newly assembled with some mmm issues

[Mick_geeetechi3]

Hi, I just assembled my aluminium Prusa i3 clone and had some issues upfront and would love some assistance.
1. Bed home locs. The bed homes off the plate defaulting to about 10mm away from the home corner. In x and y axis.
2. X axis movement is about 3x as far as it should be I think by steps. I have a 20x20 plate, and it seems ok on the y axis, but on the x when moving by 10mm increments it crashes into the far side at 60mm, or 6 clicks. Noting the extremity of this, I wasn't convinced it was just a calibration issue. Thoughts?
UPDATE: THE PCB was missing a jumper and therefore changed the step configuration of the driver - FIXED.
3. LCD screen. This boots ok, but sometimes i lose the visual feed altogether, and other times in displays gibberish that looks like wingdings font.
UPDATE - REPLACED. OCCASIONAL NOW.
4. Card reader on lcd back is not picking up a card. Tried 3 different ones. No joy. Need to Replace?
REPLACED - FIXED.
5. Z axis issues. The z stepper were clicking/jamming on upwards motion especially. Checked levels, adjusted angles, loosened top brackets and brass nuts, filed out top bracket holes and lubricated to limited success. Cranked the potentiometer on the z stepper and it's working with everything loosened, but worried I might cause issues long term. Replace lead screws and rods?
The rest I worked out but some of these stumped me. Have not done firmware stuff before so a little lost with that but assuming that may be the only way to resolve some of these issues.
Thanks for any help in advance.
Mick

[William]

Hi, You can 1. Check if the belt tightness is installed properly;
             2. Reconnect the lcd cable. If the contact is bad, the screen will be garbled.
            3. If you do not have an sd card, you can contact your sales staff;
            4. You can check if the lead screw of the z-axis is bent and the left and right threads are consistent. If it is inconsistent, it may cause the situation of mobile card issuance.

[Mick_geeetechi3]

Thanks for that. Tried to reconnect the LCD but still having the same issue. I have the SD card, but the reader on the back of the LCD is not identifying it. I have tried 3 different ones. Is the LCD module the issue or is it worth trying to resolder the reader or.similar

[Mick_geeetechi3]

I also ran a 50mm extruder calibration test and only ran 30mm. Is this an indicator that all of my step calibrations in my factory set firmware might be off? (Coupled with the x step issue I mean)

[William]

Hi, you can try to press the sd card slot to see if you want to read the information.And you can refer to this:https://mattshub.com/2017/04/19/extruder-calibration/

[Mick_geeetechi3]

Sorry, I am not sure what you mean by press the sd card. I have put 3 different ones in, is it a matter of applying force to see if the connections are loose?

[William]

Hi, Mick just want to determine if your card slot is loose or not, so you can't read the sd card.

[Mick_geeetechi3]

Have pushed laterally in direction of card and against the board but no change to "No sd card message"

[William]

Hi, If you still can't read it, you can contact your sales.

[Mick_geeetechi3]

Will do thanks. Any ideas or suggestions as to why the movement values are so extreme compared to the inputted values? Ie. I directed a 60mm move and it hit the far right side from home or around 200mm plus. I saw elsewhere on forums for other machines that some stepper motors have occasionally been sent out that are either 1/32 for 1/16 or vice versa, could this be it?