Unanswered Hot end losses Temp. and print stops

At first I couldn't even get it to power on. No fans, no lights, nothing. Tilted it slightly and it powered up. Leveled it and it LOOKED like it was ok, but the print head temp simply will not maintain.

Heats to 210/50 fine then I can watch the temp in MatterControl drop like a rock. Within the first layer or two it goes from 210 to 208 to 205. Once it dips below 200 the printhead stops moving. The first print the head was actually stuck to the object and I had to break it loose.

2nd print cycle, the electrics started freaking out as it neared 210. The LEDs were flickering and the target temp was bouncing all over.

Quit MatterControl and re-started print cycle number 3. This time I let it sit at 210 for some time, it didn't even finish the calibration.

Errors from log (last error just repeats over and over as long as the print is active.)

<-ok T:209.9 /210.0 B:50.0 /50.0 T0:209.9 /210.0 @:127 B@:127 [51.807]

->N21 T0*9 [51.823]

<-echo:Active Extruder: 0 [51.838]

<-ok [51.838]

->N22 G90*32 [51.854]

<-ok [51.870]

->N23 G92 E0*118 [51.885]

<-ok [51.901]

->N24 M82*47 [51.916]

<-ok [51.932]

->N25 M107*18 [51.979]

<-ok [51.995]

->N26 G0 F9000 X131.946 Y111.699 Z1.299*43 [52.010]

<-Printer stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting) [52.026]

<-ok [52.026]

->N27 G1 Z1.299*74 [52.057]

<-Printer stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting) [52.073]

 

It doesn't appear to be software or temperature related. I set up Cura per the instructions above, it runs a little bit hotter. 220/70.

Everything heats up fine, it begins printing, but the temp drops the whole time it's printing. When it went from 220 it hit 212 and stopped, even though that was 2 degrees hotter than where MatterControl started.

I'm trying a different file this time. Could be my test file was just corrupted, even though it looked fine in the software.

EDIT: Tried a different file, same issue.

 

It is likely a hardware issue. A loose wire, fan blowing on the heater block, something along those lines.

Pre-heat to 210 and then enter M106. This will turn your fan on so you can see if it is the parts fan that is causing the temperature to drop. Make sure you let the heater come up to temp before entering M106.

 

Sometimes that happens when the thermistor is loose. It will still register a temp change but the nozzle will actually be much hotter than what's being read. When the print begins the filament going through the nozzle causes the temp to drop as power is being pulled away.

Are you able to heat it up to like 280? You might need to flash the new firmware first to allow you to get that hot.

Could also be a fan issue but I've seen that less

 

Thanks Mike, I posted my own "Day 1 Tale of Woe" thread and that seemed to be the consensus there as well.

I'm going to see if I can find a repair video for it and contact support as well.

My fear is two-fold:

1) The problem started with the printer not even powering on which is concerning and makes me think there may be a deeper electrical problem.

2) It gives me the heebie jeebies attempting a repair like this on a machine still under warranty. I don't want to do anything to void that.

That being said, it doesn't go anywhere NEAR 280. The software says the max is 250 and it barely gets to 210. Most times if I let it sit a few hours it will hit 207/208 but like I say, it takes hours to get that hot.

I don't know if the time it takes to heat up also indicates a problem. When I got it close to 220 I let it warm for 1/2 a day.

 

A couple thoughts on the matter

There is potential that something is wrong with the power supply though it seems a tad unlikely. If you own a multimeter you can measure the voltage input to the ramps after you enable the heater.

As for the warranty they're pretty lax. Though I'd open the channels of communication with robo to start getting help from them.

The heat up time is alarming a few ideas.

If you measure the resistance across D10 to see what the resistance is and check the connection to make sure it's secure.

If that comes back good and the power supply is outputting the correct amount then it's almost certainly the thermistor is loose. Remove the boot around the hot end and press in the thermistor so it's making solid contact with the metal. Then try again

 

I am also having similar problems. I was in the process of printing a battery bracket for an ebike project. After a hot end removal to clear a jam the black rubber nozzle cover broke apart. Not knowing this was not decorative but helps hold the thermistor in place I removed the remaining rubber cover. I popped the thermistor into the hole for it and made one more print no problem. Like the others it drops in temp and stops printing right after it gets started. I'm getting errors as seen in the screenshot. I did not realize the thermistor wires were touching the hot end. I do see evidence of the insulation melted and the copper inside slightly exposed on the thermistor wires.. The wires are not broken as tested by an ohm meeter. I'm getting slightly over 100ohms on the thermistor, if I can trust my equipment. The wires were taped up and what I could salvage from the rubber cover was replaced to help hold in the thermistor but it still stops printing. At this point even if something was damaged from my own stupidity and lack of experience I'd like to get back up printing as soon as I can. A fresh firmware upgrade was just done. I'll set up an appointment with robo3d support. I have used there Skype service and it worked out well. Brian worked out my problems. Any help would be great as I just got started and I'd hate to lose my momentum over this.

 

Also hopefully the thermistor is reading 100kohms and not 100 ohms.

Keep an eye on the temperature or use a different software like repetier host to monitor the temp graph for any drops that are giving you those errors

 

Thanks Mike and Mark for your help with suggestions. I double checked with my ohm meeter and it does read 100k ohms not just 100 ohms like I first misread and wrote in my initial post above. Have a Skype meeting with support at 6pm eastern time, we shall see what happens. Any one know where to get reccommended replacement parts like stock hot ends, thermistor,rubber cover. I'm one to swap in new parts if I think that might cure some issues. Not interested in the v6 upgrade at the moment, and i'm fine with matter control for now, it did work for me to just print which is where id like to get back to. Looking at a chart or graph at my temperatures dropping would make me go "now what?"

 

Any thoughts on the possability of drilling and taping the standard hexagon hot end to take the screw in thermistor? No firmware changes needed in doing this i'm guessing. You know guessing tho...

 

Ok i was told by robo3d support Jerry that I need to replace the rubber boot and thermistor so iv'e filled out the online form and its a wait and see situation now. Printed solid thanks for the link to the standard hex hot end. As soon as I get back up and running i'm due to order the samples packs of the carbon fiber and more importantly the stainless steel infused filament. The ebike photos of the battery mount in white abs are just test parts/prints, someday to be altered and reprinted in??? I see the V6 is on backorder, any idea when you will be in stock with them? Mark thanks for your input on the screw in thermistor. I don't see the rubber boot, pressure fit, stock robo solution a long term way to go for holding that important part tight to the hot end.