New Rostock Max User (Has a problem)

[bhesson]

This is my first 3d printer after following the technology for two years, and i'm so glad to finally own one!!!
After a thermistor malfunction and an overheated (the PEEK and teflon melted) hot-end, I needed a few replacement parts which the SeeMeCNC team happily provided to me free of charge, thanks guys! The problem however, is that the printer now displays the wrong temp in that thermistor port.
With nothing connected it displays 22 degrees celcius, and with the heated bed thermistor plugged into it to test, it displayed 32 degrees celcius.
If someone knows what is happening that would be great! Could it possibly have been caused by the overheating?
Help please! Its been sitting in my living room useless for the last month and a half and it's killing me!!!!!!

[Polygonhell]

This is my first 3d printer after following the technology for two years, and i'm so glad to finally own one!!!
After a thermistor malfunction and an overheated (the PEEK and teflon melted) hot-end, I needed a few replacement parts which the SeeMeCNC team happily provided to me free of charge, thanks guys! The problem however, is that the printer now displays the wrong temp in that thermistor port.
With nothing connected it displays 22 degrees celcius, and with the heated bed thermistor plugged into it to test, it displayed 32 degrees celcius.
If someone knows what is happening that would be great! Could it possibly have been caused by the overheating?
Help please! Its been sitting in my living room useless for the last month and a half and it's killing me!!!!!!

If you measure the resistance of the thermistor when it's not connected to the board what do you get? It should read about 110KOhms at room temperature.

It's a little odd that you're seeing 22C with nothing connected, and it is certainly possible on a RAMPS board to damage a single input pin on the Arduino, though not by overheating the thermistor. Even if you have damaged it, there are enough thermistor inputs, that you should be able to swap to a different one, and make a small firmware change.

[mhackney]

I agree with Polygonhell, that sounds very odd. I would double check that you don't have any short circuits. Measuring the resistance of the thermistor is also a good idea. Then, hook the thermistor up directly to your board's thermistor input terminal and run launch software and connect to the printer. You should be able to hod the thermistor in your fingers and watch the temp rise. Are you using RAMPs or RAMBo?

cheers,
Michael

[bhesson]

Thanks! I don't know why i didn't think of that but changing the pin in the firmware worked perfectly! Now i just have to wait for my new parts. (waiting on USPS mail for three weeks now)
One more thing, when calibrating i can get the three carriages calibrated together using the end-stop screws, but the print-head (pen for now) is closer to the bed in the center than at the edges. I remember reading somewhere that i can change this in the firmware but i can't remember where or how to do so.

Thanks again,
Brad

[Polygonhell]

This is a good calibration guide, including the center too high/low correction
http://minow.blogspot.com/?m=0

[geneb]

When I get a chance I'll get the assembly guide updated with new calibration instructions - the paper method is a lot simpler to do than the caliper method.

g.

[bhesson]

This is a good calibration guide, including the center too high/low correction
http://minow.blogspot.com/?m=0

Thanks, this guide worked perfectly!

And just last night the replacement parts came in the mail, i have hooked averything up at this point and when i get back home today i will run the first print!!!
I will upload pictures once it is done

bhesson

[bhesson]

BTW what is the nozzle size?

bhesson

[Polygonhell]

Unless you specified otherwise it'll be 0.5mm (slightly over IME).

[bhesson]

Alright, this isn't as easy as i thought it was going to be and with this being my first 3d printer i need some serious assistance:

1. When i start the print, barely any plastic comes out (it comes out really slowly and bunches up on the nozzle)
-I tried a higher temp up to 245 degrees but i don't want to go too high considering I already burnt out an extruder
-I tried pushing the filament through manually and I was able to do it but it wasn't easy
-I just thought that part of the problem is that the extruder was a little too high off the print bed, but it still doesn't look like it's pushing out enough plastic

2. Sometimes the filament starts backing up in the extruder (instead of pushing into the tube connector it starts to come out the side)

3. Sometimes the printer stops working altogether and displays "Sleeping..." on the LCD
-Just started doing it about ten minutes ago, and after all the other problems I just shut off the printer and stopped trying to figure it out myself because i obviously don't know what i'm doing


Its late where i live and I'm going to bed but i hope to fix these problems in the morning and maybe be able to make distinguishable objects rather than stringy blobs by the end of the day.
If anyone knows the solution to these problems it would be greatly appreciated!

Thanks,
bhesson

[Polygonhell]

I'd start by verifying the temperature of the nozzle with a thermocouple, I think the current SeeMeCNC hotends are reporting higher than actual readings. However I could extrude ABS down to about 235C with mine.
If you can extrude by hand then the issue is likely slipping filament.
What rate are you trying to extrude filament at?
120mm/min is a reasonable place to start in repetier host.
It will tend to curl onto the nozzle, if you pull it clear it should extrude reasonably straight.
No idea what the sleep functionality is except perhaps the steppers turning off which they do if they don't move for several minutes.
When you say backing up in the extruder, I assume you mean getting pushed to the side or under the rollers, I fought this for a long time and finally printed a part to reduce the occurence. But I only really saw it following a large retract/resume, or trying to push filament out too fast.

[geneb]

Interesting. I'm printing at 230C right now. Go figure.

g.

[bhesson]

I'd start by verifying the temperature of the nozzle with a thermocouple, I think the current SeeMeCNC hotends are reporting higher than actual readings. However I could extrude ABS down to about 235C with mine.
If you can extrude by hand then the issue is likely slipping filament.
What rate are you trying to extrude filament at?
120mm/min is a reasonable place to start in repetier host.
It will tend to curl onto the nozzle, if you pull it clear it should extrude reasonably straight.
No idea what the sleep functionality is except perhaps the steppers turning off which they do if they don't move for several minutes.
When you say backing up in the extruder, I assume you mean getting pushed to the side or under the rollers, I fought this for a long time and finally printed a part to reduce the occurence. But I only really saw it following a large retract/resume, or trying to push filament out too fast.

Thanks for the help! I ended up bringing the extrusion speeds way down as to not put too much pressure on the extruder which solved the backup problem enough to get out a solid print.
Believe it or not i'm printing ABS at 270 degrees, which i'm going to assume is not the actual temp. (I don't have a thermocouple to check) but it works, so ya....
and in terms of the "sleeping..." it was just that on heat-up the temp passed 250 degrees which was the max set in the firmware, so that was easily fixed.
I would love to be able to print a little faster though, could you send me that part you used to help stop that back-up problem? I'm curious of how you fixed it.

Thanks
bhesson

ps. these are pics of my first completed print (as in the first to not back up in the middle of the print)

[JakeCShake]

Your first baby....pretty exciting isn't it. Congrats.....more good is to come. I have to review my failures and success and hopefully will have more to contribute soon....

[JakeCShake]

This thread may help as well..... We are all pushing for better results...

http://forum.seemecnc.com/viewtopic.php ... 6&start=40

[bhesson]

Yes!! I'm super excited for what is to come, but i still can't find polygonhell's part. If anyone could send me the .stl for it or something that would be great! I'v tried tweaking many settings, but I still can't push it out at more than 20-30 mm/s speeds without the filament coming out the side of the extruder! Otherwise, things are good, there is warping in my buildplate tho, i think ill get a piece of glass cut for that.

Thanks
bhesson

[barnett]

I got Polygonhell's extruder cap from here. I had to file the inner hole a bit until it lined up smoothly with the little hole above the rollers in the extruder. No filament jams in the extruder since that day 2 weeks ago.