Rostock V2 thermistor fail

[cgbobio]

So yesterday I decided to reseat the thermistor since nothing else seems to have been a long term fix... Today everything seems to be going well. I ran through all the setup steps, ran the PID auto tune, calibrated the Z-height and even got the filament feeding. So now I'm slicing up the PEEK fan shroud and my printer once again goes offline with a def/0. What do I need to do to reset this? I've turned off the machine, disconnected from Repetier and then tried MatterControl as well, but the printer will not reset the error.

Beginning to think I should take up kite flying instead!

[joecnc2006]

Maybe wipe the Rambo and load the firmware on a blank board. I had a home issue where the z would raised 10mm and stop and this fixed it.

[geneb]

The def/0 means that for whatever reason, the firmware isn't getting a sane reading from the thermistor. I'd check your wiring. It appears to me like you've got an intermittent connection.

g.

[cgbobio]

Almost at wits end with this... I've wiped the RAMBo at least 10 times now and reloaded, recalibrated etc only to get the dreaded def/0 popping up just before I print. I've checked all my wires just as many times and even with a meter. I've reseated the thermistor in the head and got really good readings this morning during calibration, but then the def/0 just before I was able to print.

The first time I started up the printer I got a reading of 366 on the hot end... definitely a problem. Changed out the connectors, checked wires for shorts and retested. Got a better reading of 72.1... still not what it should be from a cold startup. More wire testing and RAMBo reloading later along with the re-taping with Kapton tape around each lead from the thermistor and got a more acurate reading of 26.0. Again with the calibration etc to get the def/0 just before testing the extruder... reseated the Thermistor and waited... Wipe RAMBo again, recalibrated again, was able to get through the extruder test and setup and finally got to slice up the PEEK fan shroud. Time to heat everything up to get the plastic flowing and guess what... def/0 again! Can't clear the error after several attempts of rebooting, removing the USB cable and powering off.

Right now I have a very impressive black paperweight sitting on my desk. I think I'll go clean my pool filter before I do something to the printer that I will regret.


UPDATE: Took apart the hot end and removed the RTV from the thermistor to find that one of the leads had broken loose. Apparently the RTV was holding it in place until heat was applied and then it no longer made contact. Ordered up a few spares and will update again when I have one installed.

[bubbasnow]

this is what everyone whos cool ends up using

http://www.ebay.com/itm/321341736569?va ... 1497.l2649

[cgbobio]

this is what everyone whos cool ends up using

http://www.ebay.com/itm/321341736569?va ... 1497.l2649

Me likey! Makes sense being that those things are so fragile!

[bubbasnow]

if your going to use that style, i sugest insted of the tubing, just spread the leads, and use kapton tape

[cgbobio]

if your going to use that style, i sugest insted of the tubing, just spread the leads, and use kapton tape

4.PNG

Good idea. I was just following the documentation since it was my first printer build. Figured it would be easy since I've assembled over 12 RC Helicopters... Problem is my big hands with little parts!

[cgbobio]

Just an update on the thermistor problem... got my new one from SeeMeCNC and installed it with the kapton tape method. Everything going smoothly and first prints look very promising. Other than the PID autotune with the new PEEK fan installed, PID autotune for the bed, the proper Z-height and horizontal radius set, the filament extruder steps per mm and the filament diameter inside slic3r, are there any other settings I should be looking at calibrating? I've used the ABS preset and bumped the heat up to 230 from 225 and have seen much better prints but I still notice a little separation between passes on some layers, specifically the PEEK Fan.

[bubbasnow]

ensure you dont have any drafts and kick it up a little bit more

[geneb]

That little gap is a slicing issue. It does it to me as well.

g.

[cgbobio]

That little gap is a slicing issue. It does it to me as well.

g.

Good to know before I drive myself crazy trying to fix it! Thanks.

[cgbobio]

this is what everyone whos cool ends up using

http://www.ebay.com/itm/321341736569?va ... 1497.l2649

Hey Bubba, do I need to change any settings in the config for this screw-in thermistor or is it plug and play after re-running the PID test? Been printing solid for a few days with the standard one and once again I am getting -18C readings... seems like that RTV holds for only so long before it breaks loose on me. Can't get the temps above 220 now...

[bubbasnow]

this is what everyone whos cool ends up using

http://www.ebay.com/itm/321341736569?va ... 1497.l2649

Hey Bubba, do I need to change any settings in the config for this screw-in thermistor or is it plug and play after re-running the PID test? Been printing solid for a few days with the standard one and once again I am getting -18C readings... seems like that RTV holds for only so long before it breaks loose on me. Can't get the temps above 220 now...

in configuration.h

Code: Select all

#define EXT0_TEMPSENSOR_TYPE 97

did you do the kapton tape method i showed above?

[cgbobio]

I did do the tape method and got several very nice prints. When I powered up today I couldn't get the hot end to heat up to 225C without it failing and then giving me a -C reading. Checked the wires and nothing was wrong. I bought one of the other thermistors figuring I'd get a second extruder to mount it in... After today's failures, figured I would try it out now. Having similar issues heating the bed and hot end with the power supply seeming to be pushed to its limits... Read Shizumas post about the same issue, he solved with a different power supply.

[bubbasnow]

sounds like its heating up, then shorting to something. id definitely give those screw in a try, take care that they are jbwelded into the brass fitting and still can come lose if any tension is placed on the wire.

[cgbobio]

Really too bad that there isn't a better way to protect those things being that they are so delicate...

Checked my configuration.h file and it was already set for #define EXT0_TEMPSENSOR_TYPE 97

Just ran the autotune again, got to about 180C then jumped to a -18C then back up to 80C then started climbing again, jumped to 210C and finally timed out.
I hate to have to continually replace these things, but I'm not sure what is happening since I have the kapton tape as a strain relief on the thermistor and the zip tie holding all the hot end wires to the hot end plate. Almost ready to get a different head altogether...

[mhackney]

The simple thermistor has been the bane of desktop 3D printing far and wide! They have caused hot end melt downs, fires and other bad things. This is one reason why some insurance companies are no longer insuring homes that have a 3D printer. The "threaded thermistor" that is available on eBay is a very good solution to this problem and easy to make your own with an existing thermistor. I've not had a single failure with these, have 4 of them on my Kraken and it is whipping around very quickly so there is a lot of stress on them!

[joecnc2006]

The simple thermistor has been the bane of desktop 3D printing far and wide! They have caused hot end melt downs, fires and other bad things. This is one reason why some insurance companies are no longer insuring homes that have a 3D printer. The "threaded thermistor" that is available on eBay is a very good solution to this problem and easy to make your own with an existing thermistor. I've not had a single failure with these, have 4 of them on my Kraken and it is whipping around very quickly so there is a lot of stress on them!

I agree, the threaded Thermistor is the way to go. I just got one and will be building a new head this week with it. for $10.00 well worth it.

[Eaglezsoar]

The simple thermistor has been the bane of desktop 3D printing far and wide! They have caused hot end melt downs, fires and other bad things. This is one reason why some insurance companies are no longer insuring homes that have a 3D printer. The "threaded thermistor" that is available on eBay is a very good solution to this problem and easy to make your own with an existing thermistor. I've not had a single failure with these, have 4 of them on my Kraken and it is whipping around very quickly so there is a lot of stress on them!

I agree, the threaded Thermistor is the way to go. I just got one and will be building a new head this week with it. for $10.00 well worth it.

Are you using thermistor table 1 or 97 in your firmware for the threaded thermistor?

[mhackney]

"1" the thermistor supplied with these is the EPCOS B57560G104F

[mhackney]

BTW, I believe the Repetier thermistor list has a typo - I can not find an EPCOS B57560G0107F000 thermister, it is a B57560G0104F000

[Eaglezsoar]

BTW, I believe the Repetier thermistor list has a typo - I can not find an EPCOS B57560G0107F000 thermister, it is a B57560G0104F000

Thanks for the info, I thought it was one but I remember a user telling others to use a type 97 and now when I try to find it, it has become hidden in the thousands of other posts. Oh well.

[cgbobio]

Installed the "new" threaded thermistor from Ebay, modified the configuration.h file and updated the firmware. Still having the same issue during the Autotune test...
This is a video of the LCD as the autotune test heats up the hot end... at around 140C everything goes crazy. Prior to this, I had a working printer with the stock thermistor that just started acting the same way... I thought I had it fixed...

http://youtu.be/cS0JoPdBcPg

[joecnc2006]

Looks like a board problem with Rambo, wonder if clearing the eeprom would help.