Mhackney's Rostock Max

[mhackney]

And a little quicker than the 250mm tall vase!

At this point, I pretty much have the Rostock dialed in and its becoming pretty predictable to me. There is always tweaking based on a specific part's geometry, print goals (cosmetic, utilitarian), plastic used, etc. I am making prints much nicer and bigger and smaller than I can on my H-1 and I have it very dialed in.

[cambo3d]

hey micheal how about i just copy all your settings instead of going through all this calibration .. probably wont work but worth a try.. =p

[mhackney]

Actually that is not a bad idea. It might get people in the ball park. A couple of caveats:

stepper motor acceleration, speeds and current can be affected by your mechanical setup (i.e is your build tight, loose or just right!)
temperature measurements are affected by how you install your thermistor
material settings depend on your specific filament

[ApacheXMD]

For temperatures, maybe you could post temps measured from your thermocouple rather than target thermistor temps. And then we all could aim for those numbers?

I know hotend temperatures are material dependent as well, but like you said, it would probably get a lot of us close.

[mhackney]

All the temps I'm reporting are calibrated and are within .5 deg C of the thermocouple measurement.

[cambo3d]

what happened to your dual extruder setup? did you get it working?

[mhackney]

Still in progress. One thing I've learned here is not to post information pre-maturely. It causes an inrush of emails and PMs and even posts asking for more information and details. It's better to get everything sorted and complete and then post!

cheers,
Michael

[xnaron]

The more I read your thread the more enlightening this is. You have veered away from stock in some respects like the heater cartridge and the power supplies. I'm trying to replicate your results but I haven't been able to. I have had issues trying to hold the temp on the hotend after I turn the fans on. This is happening without the heated bed turned on. I think I will try a heater cartridge. Is this the one you used? http://www.ebay.com/itm/New-3D-Printer- ... 337eae85ed

thanks,
Brendin

[mhackney]

xnaron, the heat cartridge is a nicety but certainly not a necessity. If you have difficulty maintaining temp with fans on, you likely will with the cartridge heater too. Sounds like you have too much air flow, air directed too much at the nozzle, or both! I use a 1" fan pointed at the PEEK to cool for PLA. And off-head fans for cooling the print. I see a lot of people here and other places use what I consider way too much air flow directed at the hot zone. I'd try that first.

Yes, that is the exact unit and vendor I used.

regards,
Michael

[geneb]

I'm going to try wrapping my hot end in silicone tape to see if I can prevent the same issue that xnaron has - we're both running the same squirrel cage layer fans.

g.

[mhackney]

I know the RepRap crew wrap their JHeads in insulating tape and button it up with Kapton.

This is my 1000th post here! Wow, time flies.

[Polygonhell]

I have silicon tape around my heater block to help prevent excessive cooling from the fans, and it works very well.
I used the silicon tape because it's what I had handy for high temperature tape.

[xnaron]

I have silicon tape around my heater block to help prevent excessive cooling from the fans, and it works very well.
I used the silicon tape because it's what I had handy for high temperature tape.

Can you post a picture of it?

[Polygonhell]

I have silicon tape around my heater block to help prevent excessive cooling from the fans, and it works very well.
I used the silicon tape because it's what I had handy for high temperature tape.

Can you post a picture of it?

The blue thing is the crimp I used to connect the resistor wires together, I basically cut a slot in the tape to accomodate the wires.
The somewhat untidy trimming at the bottom is because I originally put the tape on when I had the longer original nozzle and when I swapped out the nozzle I had to trim the tape.

[mhackney]

I was printing today and noticed the hot end temp fluctuating wildly as seen here:

I shut off the heat because I thought I was on my way to a meltdown. I checked the wiring while it continued to print during the cool down and all seemed ok. So I set the temp to 190°C and turned the heater on and now seeing this:

I usually have rock solid hot end temp and nothing like this oscillation. It's been oscillating like the 2nd screenshot above for 10 minutes now.

Time to check the thermistor and connections.

[Polygonhell]

Are you running the hotend at 24V?
It's possible one or both are damaged, I'd check your resistance at the board.
If it's changed significantly then the PID values would be incorrect and you'd see what you're seeing.
I'd replace the resistors if they are damaged rather than rerunning the PID Autotune.

[mhackney]

No and never did. This is a 12V cartridge. First attempt using Slic3r 9.9 - I am printing 2 objects on the platter, the ramp up or down happens when moving from one to the other! Need to look at gcode.

EDIT: and I did retune the PID for the cartridge. I will check thermistor connections. gcode was clean with respect to temps, and since I see the big change on rapid moves, maybe there is a loose connection. Maybe even the smaller cycles can be correlated to moves within the layers - they were very regular actually.

[Polygonhell]

Yeah then GCode should be the first thing you look at, could be something odd in 0.9.9.
The other thing to look at is the potential of something applying significant cooling during the move.

[mhackney]

[img]http://www.myinkproject.com/wp-content/ ... -robot.jpg[/img]

I discovered my "wild temperature oscillation" problem. It was, as predicted, a loose thermistor. The silicone (Permatex Ultra Copper) had peeled off the hot end allowing the thermistor to slide in and out of its hole. An easy fix BUT if I was not attending the printer and the thermistor dislodged completely, a meltdown and fire might have ensued. So please be careful out there folks, and watch closely and don't print unattended.

[Eaglezsoar]

[img]http://www.myinkproject.com/wp-content/ ... -robot.jpg[/img]

I discovered my "wild temperature oscillation" problem. It was, as predicted, a loose thermistor. The silicone (Permatex Ultra Copper) had peeled off the hot end allowing the thermistor to slide in and out of its hole. An easy fix BUT if I was not attending the printer and the thermistor dislodged completely, a meltdown and fire might have ensued. So please be careful out there folks, and watch closely and don't print unattended.

Perhaps wrapping the hotend with silicone tape after the Ultra Copper dries would provide an added layer of safety.

Carl

[mhackney]

Yes, I have not done this in the past but this time I wrapped with Kapton tape to keep it in there.

I thought when I ordered a batch (20) of the cartridge heaters I saw a similar cartridge thermistor or thermocouple on eBay. But now I can't find them. Anyone seen these?

[Av8r RC]

Sounds exactly like an almost disaster I had about a week back. I was removing my hotend to take some measurements to install my Budaschnozzle. I heated up the hotend to extract the filament. Then proceeded to disassemble the hotend platform. And as I unplugged the thermistor it pulled out of the high temp silicone.

Maybe we need to come up with a better solution than silicone for this.

[Eaglezsoar]

Sounds exactly like an almost disaster I had about a week back. I was removing my hotend to take some measurements to install my Budaschnozzle. I heated up the hotend to extract the filament. Then proceeded to disassemble the hotend platform. And as I unplugged the thermistor it pulled out of the high temp silicone.

Maybe we need to come up with a better solution than silicone for this.

Another solution is epoxy like Arctic, but you would have a bear of a time getting the thermistor out if needed.

Carl

[mhackney]

Well, I replaced the broken thermistor in the hot end. I also added a 4 prong locking connector for the heater and thermistor to make it easier to remove the hot end assembly in the future.

Now, when I connect, in the Repetier Host status bar (bottom of the window) I see the hot end thermistor come up set at 0°C then immediately drop to -20°C. I do not see any display for the heated bed. The LCD display shows a lock icon then def/o° Bdef/0°

I swapped the hot end thermistor to the 2nd port on the RAMBo and changed the pins.h file to use this port for hot end one, same result. I also tested the thermistor and wiring all the way back to the connector to RAMBo. I am seeing the proper resistance for the hot end and heated bed resistors there. This -20° reading is what is displayed when no thermistor is hooked up at all.

I aslo swapped the hot end and heated bed thermistors and tested them one at a time in each port. Same result, no heated bed display, -20 hot end display.

I fear that I fried all of the thermistor ports on the RAMBo although I don't know how that could happen for the hot end 2 port since nothing was connected to it at all.

Just noticed the log pane in RH shows:

< 7:31:16 PM: extruder 0: temp sensor defect
< 7:31:16 PM: heated bed: working
< 7:31:16 PM: Printer set into dry run mode until restart!


Any ideas anyone?

[Eaglezsoar]

Well, I replaced the broken thermistor in the hot end. I also added a 4 prong locking connector for the heater and thermistor to make it easier to remove the hot end assembly in the future.

Now, when I connect, in the Repetier Host status bar (bottom of the window) I see the hot end thermistor come up set at 0°C then immediately drop to -20°C. I do not see any display for the heated bed. The LCD display shows a lock icon then def/o° Bdef/0°

I swapped the hot end thermistor to the 2nd port on the RAMBo and changed the pins.h file to use this port for hot end one, same result. I also tested the thermistor and wiring all the way back to the connector to RAMBo. I am seeing the proper resistance for the hot end and heated bed resistors there. This -20° reading is what is displayed when no thermistor is hooked up at all.

I aslo swapped the hot end and heated bed thermistors and tested them one at a time in each port. Same result, no heated bed display, -20 hot end display.

I fear that I fried all of the thermistor ports on the RAMBo although I don't know how that could happen for the hot end 2 port since nothing was connected to it at all.

Just noticed the log pane in RH shows:

< 7:31:16 PM: extruder 0: temp sensor defect
< 7:31:16 PM: heated bed: working
< 7:31:16 PM: Printer set into dry run mode until restart!


Any ideas anyone?

How about reinstalling the arduino firmware.
Something could have become corrupted.