First build problems

Hey everyone,

I've just completed the build of my prusa i3 with parts i've collected on aliexpress and ebay. So not really from 1 seller.
I've uploaded the Marlin firmware, changed some parameters like motherboard 33, thermistor values.
So far i am able to connect my printer with pronterface, and to move the axis a little.
One problem I have is the smart controller display is only showing white squares.
Another concern is i've used a 20 kohm thermistor for the heatbed, and only a 10 kohm is selectable in the configuration.h. This gives me a temperature of 7°c where it should be around 23°C. The thermistor on the hotend is giving the correct value.
Allso the fan on the hotend is connected to D9 on RAMPS, but doesn't start when i'm heating the hotend.

I'm still waiting for my glass plate and springs to level my bed to really start printing.

Any ideas to solve this?

For the display, try swapping and/or rotating the connectors. I have found that different manufacturers do not have a consistent approach to the display connections. Not sure what to suggest about the thermistor apart from swapping it for a standard one.

Could you provide picture, and some other information such as hot end type you're using and specs?

Allready tried swapping the cables, no succes. However i've allready seen the display working with hephestos firmware, but this gives me other problems (no connection from pronterface)...
I prefer Marlin firmware.

About specs:

Frame i've used: [www.benl.ebay.be]
Extruder: [www.benl.ebay.be]
Electronics: [www.aliexpress.com]
Power supply: [www.aliexpress.com]
Steppers: astrosyn 17pm-k502-g3st

Pics from my build:

D9 is for second extruder. Extruder fan is connected directly to 12 volt power.

OK, will change that!
The display problem is solved, had to uncomment my type of display in marlin configuration!
I am ready now for leveling of bed, and testprint!

Okay, it's actually dependent on the motherboard you choose, D9 actually can be either for second hotend or print fan that has pwm. for extruder fan, just hook it to either 12v input terminal (not the one 10A input based on the ramps diagram). Mine got almost everything hooked up, hotend fan at 12v output to the left of x axis stepstick, print fan at D9 controlled by pwm from gcode generated by slicers

Ok, just 1 major problem before i can start printing. My extruder doesn't move (it does e very little bit) en is making a lot of noise.
I've tried moving the stepper to the pins of the x axis, where it works perfectly,
I've also switched the stepper driver with another one, which stays the same.
This way I figured out it is not a electrical or mechanical problem.
It has to be something in the configuration, but I can't figure out what exactly.
Any ideas?

https://youtu.be/sCFc1rp-3ak

Increase the current in stepstick by turning clockwise on potentiometer on it, don't turn it a lot, because the current are quite sensitive to slight turn, this might help, also try to loosen the extruder tension spring

I think this is unlikely, because I've tried the extruder on the pins of the x axis with the stepstick of the x axis, with no changes at the spring tension. This way it worked perfectly.
After that i've put the extruder back to it own pins (E0) but switched the stepstick with the one from the x axis (what worked on the other pins), en this gives me the same problem.
Could it be that only the extruder settings require a higher current? I'm a bit scared changing the current on the stepstick to damage it. No more spare ones...

The seller i bought pieces from provided me the firmware they recommend, and everything works. It had to be some setting in Marlin. To bad i don't know which one.

Did my first prints, and it works. However the extruder seems to be making a lot of noise, and is trembling a lot (what's causing inaccurate prints). I've made some videos, one while working, and the other one opened, with no tension on the spring, and no fillament.
[www.youtube.com]
[www.youtube.com]
I've tried messing around with the potentiometer on the stepper driver, no changes...
I've tried changing the axis steps per unit, but that has probably nothing to do with this issue.

Did you install the jumpers under your stepper driver? Lots of people forget them. If you don't know what im talking about then they are probably your problem.

Yep, that was the problem, find out yesterday thanks to some people on this forum. Everything works fine now. Thx for all the help!! Learned a lot in this build!

Edited 1 time(s). Last edit at 10/26/2015 03:26PM by Nicken83.

Where do I find the doco for the jumpers under the drivers? My replikeo came with one jumper connector. I didnt install any.

[reprap.org]
It's actually really simple, if you have a RAMPS and 1/16 steps drivers for your steppers, you need to install all the jumpers (3 under each driver).