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Thermistor's not working.
I installed a mk2b on my printer after accidentally breaking the factory glass. I have the machine flashed over to repetier firmware and i'm repetier host. I have installed and printed with an E3d V6 extruder on the da vinci. My first print with this new extruder I stopped a print after a bad start to the first layer and pulled the extruder to the far right to clean it with a wire brush. Being an IDIOT I started brushing the extruder nozzle and brushed right over my soldered connections to the heat bed. The lights flashed and I was presented with inaccurate temps for my extruder and heat bed.

After that mistake my display shows my Hot bed sitting at 149 when cold and my EXTRUDER WILL warm up but it will not display the correct heat. My bed will not even activate because the machine thinks it's already 149 degree's. I was hoping i could just replace a diode or resistor but i can't see anything on my motherboard that looks damaged. I thought maybe there was a short in the mk2b heat bed, but my Thermistor on the extruder isn't operational either. I traced the wires back to the motherboard and can't find any burnt up connections. I'm at a loss right now and hoping i won't have to figure out how wire in a new motherboard. If anyone has seen a problem like this or heard of anything like it please point me in the right direction.

I'm ordering some more Thermistor's to replace and if by some miracle replacing them works i'll write that off as an easy win. Otherwise i'm not sure where to start to get my Thermistor's in working order again.

Ouch! It is very bad that!
The risk is whether the analog inputs of the Arduino Due that have blown.
Look here on the motherboard:[Image: davinciboard_2014-10-23.jpg]
I don't see any visible damage. I have some Thermistor's and a new mk2b in the mail heading to me right now I have a sneaking suspicion that i might have blown out my Thermistor's. Thank you for your reply I will update my status by the 28th, I'm hoping it will be an easy fix.

Which thermistors did you order for replacement?

I need to figure out how to adjust Thermistor settings in the compiled .bin file.
If anyone has replaced their thermistor with success, please share details of the part you used. I put in what I thought was a 100K 2.5 mm that isn't working. Registers 114 C but easily melts ABS, suggesting it is way off. I shut it down immediately to make sure I didn't get a burn out.

Did you modify the thermistor tables in the firmware?
did you ever find a resolution to this? I also had to replace my thermistor and have been having trouble with it not reporting correct T. I used a RioRand 100k ohm NTC thermistor off Amazon. When I do a heating cycle it reports 200C but the hot end is smoking and apparently much hotter. I'm on stock firmware so I don't know if there's a way to update the table. Does anyone know the stock thermistor?
I found a thermistor that works great, I can heat up to 220C without any burning. I will post a link to it one sec.

*edit* here it is:

I have the same issue with Aaron in the first post. Any other with same problem find the solution for this?
Its the table. I learned a little bit about the 3950 beta 100k thermistors. They work backwards to what the davinci thermistor uses in tables. The 3950B 100k NTC resistors use high resistance for low temperatures and low resistance for high temperatures. I own a 3950B 100k NTC thermistor and I am trying my hardest to get the table right.

I generated a table today that I am going to try, so the table below should be used at your own risk. If you use the table you need to watch the hotend and make sure it doesnt over heat. I have a laser heat gun so I can monitor my heater.

EDIT* My table is wrong, the 3950B thermistor has a max adc of 1023, so I need to tweak it.
smh - some peoples' children...
This is the only post i've seen from you trying to help people. In fact every post I see you post things is just either complaining or being "mrknowitall"
Really? All of your posts are complaints and stupid questions. Plus you're using MY TABLE CALCULATOR.

Last time I try to help you, asshole. Cheers!

There needs to be a 3d printer abuse hotline... someone needs to save those machines from you before they're nothing more than scrap metal.
Not to blame you but your table sucks IMO. It is way too simple to generate a correct table value. You have no input for adc
ADC is very important. If my thermistor can't go over a certain resistance then the calculator needs to know this.

Stupid questions, thats how ignorant and non helpful you are. I just owned my printer and got into 3d printing so I am happy how far I have came/learned. I am far from stupid and just because you are selfish in helping new people to the field shows how selfish and ignorant people can be with knowledge. I believe any knowledge should be shared to the public and even if its a "how to tie my shoe question" I am willing to help. So if you are not going to be helpful to people and give vague answers on this forum or just complain about people posting the same questions then LEAVE!
You don't need to input ADC, the da vinci ADC was already factored in. Showing how stupid you are. Please fuck off. Learn WTF you're talking about before you try to criticize.

I'm sorry I've invested over 20 years in electronics and have a degree in computer engineering. That didn't come to me for free. Plus I grew up working around my father's business, with plastic extrusions machines worth millions. I'm happy to provide pointers, but I'm not going to hold your hand and wipe your ass for you. Take some initiative and learn something... honestly you don't come across as very intelligent.

You only half read/understand advice given to you... jump to conclusions... fuck things up... then blame everyone but yourself (blame xyz, blame your ebay extruder, blame me, etc)
But what do I know, your NTC must be backwards.... must be completely different from the 2 3950s I have here in use... ROFL

Let me know your address before you throw the printers out the window, I'd be happy to collect the spare parts.
I don't even specialize in electronics. I also don't need to use profanity language when I am angry. Why? I respect people. I can respond in what I specialize career wise but I think that is unnecessary. I don't need to give a 20 year bio to prove that I am not intelligent. I've been into 3d printing for one month, one month. Understanding electronics is not that difficult. I just don't want to waste time doing this as I need the printer for rapid prototyping.

And yes greentech extruders are junk. I would be surprised if you thought they weren't junk. IMO an extruder shouldn't need screws grinded down to function correctly.

I am done arguing with you because you are just attacking new users to 3d printing. All you do on this forum is attack.
And the Davinci factored in ADC is 279? or around there. Why on a max adc table of say 1023 does the values never go above 1023?

Yet for davinci the values can range 1000-4000ish

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