Bought off chinese website, here are troubles

hello,
i am new to 3d printing, and bought a Reprap kit with Huxley board. here is a picture of it



i made all the connections according the diagram and checked the connections for any error with the mutimeter. Once assemble i started the machine using the "repetier"
software and in manual mode checked all the movements. It worked perfectly fine in X, Z, and Y direction.

Then i gave it a job to do and suddenly smoke started to come out of the board where "BED" wires go. keep in mind that while connecting bed wires, there was no negative and possitive. i quickly switched off everything, then i turned on taking "BED" wires out and checked for the X,Y,Z movements and it worked fine. While the machine was on the extruder caught fire. and here is a picture of it :



After this incident, the board connects to the computer but nothing works. !

So what do you guys think happened ? how can i get it fixed ? is the extrutruder and board dead ?

Did you wire the extruder sensor (5v) and the heat elements (12v) wiring corretly? i.e you weren't pushing 12v down the 5v sensor cable to the sensor? Although i wouldn't expect it to catch fire like that, just burn the board out.
Did you check the sensor resistance (as per instructions) before powering up to confirm all the wiring?

Just some thoughts
Graham

The first issue (bed wires) probably resulted from the connectors not being tight enough. It's also possible that the wire was dirty. If you nicked the wire / cut strands when you stripped it, that's a third thing to check.

The extruder looks like it went over temperature. I would guess that the temperature sensor wiring or the sensor failed. What was the temperature readout saying as the machine operated?

"Did you check the sensor resistance (as per instructions) before powering up to confirm all the wiring?"

There were only some crappy chinese instructions with them hardly said anything about wirring . so No i did not check any thing. can i get these instructions you are refering to from anywhere now ?

@uncle bob,
the temp. on Repetier was 780 and yeah it went through over heat.

Thanks alot for input, but guys now what should i do ? can i get this thing up and running ? what should i do with it now ? i have a thesis to take care of and need it up and running.

please please help me guys ! guide me. should i get another board ? guide me so i can get it functional.

thanks

You might be able to save the hot end hardware itself, if you can replace the heater element or resistor that was used. Same for the thermistor.

Does the hot end have a PTFE tube inside? Those are easy to find and cheap.

How much time do you have?

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Yvan

Singularity Machine

is there a way i can sell this thing off as is ?

i have learned my lesson and i would simply buy a fully assembled one !

because it seems i would need to invest time in learning stuff before i can fix it like i dont know what PTFE even means

Edited 1 time(s). Last edit at 12/15/2013 01:11PM by zahmed.

Selling a busted machine is not easy...

Do you know other people who are into these machines?

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Yvan

Singularity Machine

non !

Ok then what is the right coarse of action then ? how do i fix it ?

To fix it with less than major crazy effort:

1) Get a real hot end from the people who designed it. J-Head from hot ends.com is one option. The E3D and ALU-Hotend people both have their fans. Get the whole setup with heater and thermistor. Cost delivered should be under $60 (US).

2) Check out the board, especially the hot bed connections. Solder the hot end wires directly to the board if your terminals are shot.

3) Use the DVM that I think I see on the far right to check out the power supply I think I see on the far left. Also check out the +5 on the board.

4) Make sure all the wire connectors are *tight*. Give each wire a good tug to be sure it's in there properly and then re-tighten if needed.

5) Re-check all the wiring for shorts and opens.

6) Get the heated bed running and make sure it gets up to around 100C in under 10 minutes. If it does not, it needs to be replaced ($30 or so). There are a lot of defective ones out there.

7) Check each motor and end stop for proper travel and home location

8) After the heated bed has been running a few hours re-check the bed level

9) Check the thermistor input for the hot end with a 100K resistor - make sure it reads about 25C.

10) Check the hot end FET to be sure it's not blown. Any handy power resistor in the 10 to 50 ohm range will do for the check.

If the electronics board is blown, you will have to replace it. I'd go with a Mega / Ramps 1.4 combo. The pair will be less than $40 delivered.

The used board is a Melzi board. Wiring instructions for a similar printer with this board ( RepRapPro Mendel ) can be found here RapRapPro Mendel Wiring Instructions

@ uncle bob,

thanks a lot, i will start working on each of the step you defined, and would bother kind yourself again and again for guidance along each step.

@gurz
yes, thats exactly the board, i wish i know this website earlier so i could do the wirings accordingly. where can i buy this board ? moreover how can i check if the the board i have is working or not ? "although i saw some smoke comming out"

@uncle_bob,

how can i check my parts if they are faulty or working ?

How I would go about it:

1) Your hot end is a mess, I'd just replace it. Pull it off of the printer and get a new one on order.
2) Check the power supply first. If it's not putting out +12V nothing else is going to work.
3) Check the printer via USB with your PC - does it connect at all? If so move on. If not - likely new board
4) Start with the motors, one axis at a time. Make sure each one moves when you tell it to do so from the computer.

stop, relax, get away from the printer for a bit

5) Check that everything is mechanically correct. Nuts tight, bed level, each axis moves without binding or pulling wires.
6) Check to see that the heated bed temp shows about 25C.
7) Swap the heated bed thermistor over to the extruder therm and make sure it reads 25 C. Then put it back where it belongs.
8) Try heating the bed. Watch it, make sure it does not run away, pull the power plug if it goes nuts.
9) Heated bed should start going up in temp within 30 seconds. If not check the thermistor mounting on the bed.Also check the wiring.
10) Heated bed should get to 100C in < 10 minutes. If it does not, it may be high resistance, the wires may be to small, or the board may be blown
a) touch each connection, the really hot one has a problem
b) grab the wires, it they are hot, they are to small
c) connect a amp meter in series with the bed, it should pull > 10A, preferably 12A.
d) check the power supply - is it still at +12?
11) Let the heated bed try to run for a couple hours, watch it from time to time to be sure it's still hot

take another break

12) Start going through the firmware to make sure the steps / mm and end stop locations match your printer
13) Make sure the X, Y, E max feed rates are < 300. The Z max feed should be < 4
14) Make sure the X, Y, E max acceleration is < 500, The Z should be < 10
15) It's now safe to check and see that the printer homes and that the end stops work correctly. Start with one axis at a time.

That's about all the check out other than the hot end FET. If you have a 50 ohm 5W resistor, put it on the hot end heater controls with the heater bed therm plugged into the extruder therm contacts. You should notice it getting warm in under 10 seconds.