Heater pad leads question.

[dlw]

The heater pad has one short lead with a brown connector.
A long lead with raw ends. I know where the long lead goes but not the short one.
The only other connector besides the fan connectors is labeled 'Root'.

Any ideas on how the heater pad connects?

dlw

[RetireeJay]

Looking back at your other post about the main board, I see a red and black pair of wires going to a connector on the right hand end of the board. I think this may be a mistake. On my printer, the wiring from the Hot End heater is red and black; the wiring from its thermistor is white and black. Yours may be different, but check carefully. The Hot End and the Heated Bed both draw significant current, so the Heater connections are both at the left end of the board, adjacent to large (TO-220) MOSFET transistors. The Heated Bed heater on a Rev F board connects with screw terminals, and the Hot End Heater connects to a standard header right next to the screw terminals.

Then, on the right end of the board, there's a connector for the Hot End Thermistor and another connector for the Heated Bed Thermistor. That may be the brown lead you are talking about, although it seems like you may need to find or create an extension for it.

Fundamentally, the Rev F board is an evolution from the Rev D board pictured here: viewtopic.php?f=6&t=3922. Basically, the arrangement of connectors follows the same pattern. The heated bed connector is now screw terminals and they've added another fan connector. Some things have changed regarding the Z "endstop" switch (different numbered versions of the Ref F board have different options) - but essentially the old Rev D map is a pretty good guide to finding things on the Rev F board.

[dlw]

RJ, thanks for replying. Apologies for the delay.
Attached are 3 photos. On the photo of the top of heatbed, is there a thermistor there?
In photo of mainboard, the red and black wires come for the heatbed; would that be correct?

I'm trying to be very, very careful. Can not afford to keep replacing mainboards.

Thanks,
dlw

[RetireeJay]

OK, you have me confused now.

1) In your first picture, I would normally take the (thinner) black-and-white leads to be the ones for the thermistor. But the thermistor is normally located closer to the center of the bed, certainly not on a tab at the edge of the bed. Its function is to tell the Printrboard the heated bed's temperature for purposes of controlling that temperature, and the edge of the board is not a good place to monitor that temperature.

2) I can't tell much from your second picture except that there is a resistor shown (10K ohms, I think); this implies that you probably have an indicator LED on the board telling you when heat is being applied. No problem, except now it means if you want the LED to work you have to observe the correct polarity of hooking up the power leads to the board. Did the board come with any documentation?

3) This picture is really, really confusing. You seem to have a cable sleeve with two pairs of red and black wires arriving at the board. What happened to the black-and-white pair from the thermistor? Where are they? Both of your red-and-black pairs seem to be heavy-gauge wire, which implies that they are both for heater elements, i.e. one for the bed and one for the hot end. Is your Hot End hooked up in this picture? You show a red/black pair connected to the Hot End connector, but nothing connected to the Heated Bed power connector. (The way you have oriented the picture is opposite to the "left/right" orientation I use, based on having the printed legends right-side-up). Basically, for the Heated Bed, one red/black pair should be going to the green screw terminals adjacent to the Hot End connector. The other pair should be black and white from the thermistor, and should be plugged in to the other end of the board.
Also, look at the arrangement: Heated Bed Power is the green screw terminals which in your picture is above the Hot End Power. On the other end of the board, the same orientation applies: Heated Bed Thermistor is above the Hot End thermistor connection. Draw parallel lines across the board from Power on one end to Thermistor on the other end. This picture shows how the board connectors are arranged.

Printrboard Htr & Thrmstrs.PNG

[dlw]

Obtained heaterbed via Ebay for $10 and free shipping. No paperwork. The way the tape over black/white wires look, it appears added on later.
As shown, there are no other leads.
The black/white and black/red leads are stock with printer.
The black/red lead from heaterbed will go to green connector. Is polarity important?

[RetireeJay]

I guess you are on the right track, but I still don't like seeing the thermistor at the extreme edge of the heated surface. It won't return an accurate temperature for the majority of the bed. Your bed will be much hotter in the center than what the thermistor is telling you for the edge. Apparently the black/white wires that started with the thermistor get spliced into red/black wires somewhere inside the flexible tubing (a bad practice). But it's clear enough that the brown connector is intended to go on the thermistor connector on the board, and the bare ends of the other black/red pair are intended to be inserted into the screw terminals. Personally, I'd double-check with an ohmmeter. The thermistor at room temperature is in the ballpark of 100k ohms (+/- 20% to account for actual room temperature). The heated bed should measure just a few ohms.

Polarity? Two "IF's": IF the heated bed has an LED indicator (which I think it does, based on seeing the 10K resistor) and IF you want the LED to light up when power is being delivered, then yes, polarity matters. Otherwise it doesn't matter. The heated bed will heat just fine regardless of polarity. Printrbot did some strange things historically with the colors of the leads for the heated bed, so I can't really tell you confidently which polarity will make the LED light up. But you are unlikely to do any permanent harm to the LED if you connect it backwards for a little while, so just experiment to find which way works for you. You can't hurt the Printrboard by having the polarity wrong.

[dlw]

Thanks RJ.
I will remove the thermistor by clipping the wires.
Order a thermistor and should be good to go as far as this part is concerned.

Still need to figure out how to attach the 400 watt power supply, and
how to print on glass... coming soon.

Thanks again,
dlw

[RetireeJay]

I will remove the thermistor by clipping the wires.
Order a thermistor and should be good to go as far as this part is concerned.

Just move the thermistor to the center of the bed by extending the wires; no need to order a new one.

[dlw]

Does it go on top of heaterpad or under the steel bed?

[RetireeJay]

As close to the actual heater as possible. I presume that would be underneath the heater, but above anything else. If there's a metal bed under the heater, it should have a "well" machined out to accommodate the thermistor and its leads. If there's no "well", then the first rule of 3D printing is that the bed has to be as flat as possible, so definitely don't create a lump or a bump. Then figure out how to make the thermistor reflect the actual bed temperature most accurately.

[blort]

Jay,

on the PBSM heated bed first party by PBHQ there is only a small well for the thermistor at the edge. even the first party product doesn't have a channel going all the way to bed center.

the reasoning is that the bed overall is a largeish hight thermal conductivity heatsink. temps at the bed are generally close across the entire build plate, and a long channel to the center would actually reduce the mated contact surface between the build plate and the head board.

yes the thermistor goes between the heat board and the build plate. it typically gets wrapped in a scrap of kapton to keep from shorting against the build plate. the pic looks like it is just using cellophane tape with a tiny bit of kapton over the thermistor bead. even if the cellophane broke down and the bead didn't sit perfectly against the heating element, you should still be in an ok temp range as long as the bead stays in the "well" surrounded by reasonably hot stuff on all sides.

if there is no well in the build plate, yes it would be better to put the bead on the heat plate than bend the heat plate while trying to sandwich the bead between the two flat surfaces. the most important bit is ti keep the bead on the hottest part to regulate against runaway, and secondly to ensure max contact surface between heat plate and build plate for best thermal transfer and equilibrium between the temp of the build plate and the heat plate. I read that you intend to print on glass. printing on glass will interfere with the use of an inductive probe ( as in the inductive probe won't work and you lose autoleveling, inevitable nozzle crash into bed) . you also won't have the thermistor well carved out of a glass build plate. Frankly I am challenged to even think of how you would use a glass plate with a PBSM to get the appropriate belt movements and support the heating element if you didn't have a metal plate. if you have the original powder coated bent metal plate, stop now. you really should reconsider heating up that bent painted sheet metal.

if you have the mic6 bed from pbhq with a thermal well and all the aluminum goodness, why use glass when you can keep your probe working and stick using kapton?

polarity on a DC heater element does not matter in the slightest. it's just a high resistance metal trace on the board between the two leads.

[dlw]

I bought the special glass because I did not think printing on the headbed was a good idea.
Nor, printing on tape on the heatbed either.

I was planning on printing on the glass with tape directly over the heatbed.
The glass will fit between the screws perfectly.

Also, the power supply, ATX 400 watts) has only four male connectors.
Printrbot has six with jumpers.
How is this handled?

20170405_135841.jpg

20170405_135841.jpg

[RetireeJay]

Also, the power supply, ATX 400 watts) has only four male connectors.
Printrbot has six with jumpers.
How is this handled?

The ATX connector in your picture has a red wire, a yellow wire, a black wire, and what may be another red wire. This is the wrong connector. There should be at least a 4-pin, and preferably a 6-pin connector coming out of the ATX with 3 yellow wires and 3 black wires. If you have the 6-pin connector from your ATX, it plugs directly into the Printrboard (Rev F).

PowerToRevFBoard.jpg

If your ATX supply only has a 4-pin connector (2 yellow and 2 black) then you need to use a special jumper to make the connection. It's physically possible to plug the 4-pin connector into the 6-pin socket, but bad things will happen if you do that.

[dlw]

If your ATX supply only has a 4-pin connector (2 yellow and 2 black) then you need to use a special jumper to make the connection. It's physically possible to plug the 4-pin connector into the 6-pin socket, but bad things will happen if you do that.

There is a four pin with 2 black and 2 yellow.
How do I make the jumper or where can I find one?

[RetireeJay]

There is a four pin with 2 black and 2 yellow.
How do I make the jumper or where can I find one?

https://printrbot.com/shop/4-to-6-pin-power-extension/

[dlw]

Wiring problem???

12.23v from power supply.
New main board.
Pressed reset button.
No green light. Power is on when photo taken.
Cura does not see it.

Any help appreciated.
dlw

20170412_095504.jpg

[RetireeJay]

If the green light doesn't come on, then generally I'd say the board is not receiving power. However, the green light is actually wired to the 5V supply that's generated on-board. So if you have 12V coming in to the board but the green light doesn't come on, then suspect something is shorting out the 5V supply. Try unplugging everything except the incoming 12V power and see if you can get the green light to come on. If it does, then plug in one thing at a time until you find what makes it go out. (Turn off the power every time you make a change to what's plugged in or not plugged in, so there won't be transients caused by plugging in or unplugging an inductive load).

[dlw]

The green light never came on when unplugging the connectors one at a time on the new board or the old board.
Both boards bad???

[RetireeJay]

Are you sure that 12V is actually present on the board?

[dlw]

Yes, I checked with a voltmeter by inserting leads in all 6 opening on the female power plug.
When checking ohms, I get a reading of "1" across each connection.
I think that means dead shorts.

[RetireeJay]

If you had dead shorts, then no power supply would deliver 12V.
That said, all the black wires are supposed to be shorted to each other, both on the cable from the power supply, and on the board. In similar fashion, all the yellow (or red) wires are supposed to be shorted to each other.
The red or yellow wires are supposed to be at +12V compared to the black wires. From your photograph, it appears that you have somehow wired the power from the ATX to go through the barrel connector on the chassis. Perhaps you have the polarity backwards? This would not be good; there's a pretty good probability of damaging the board if you connect it backwards.
It would be far, far preferable to plug the 6-pin yellow/black connector from the ATX (if available) directly into the board, bypassing the barrel connector. It should look like an earlier picture I posted.

[dlw]

Big mistake in posting. The original power supply is connected in that photo, not the ATX
However, it was the same with the ATX and wiring adapter from Printrbot.

[RetireeJay]

So referring to my photo posted on the 5th, the three pins of the power supply plug that are closest to the edge of the board (black wires) are Ground, and the three pins that are away from the edge of the board (yellow wires in my case) are +12V. (Printrbot's adapter may give you red wires instead of yellow, but ultimately the wires coming from the ATX power supply are coded yellow for 12V; red is for 5V.) Is +12V what you measure? Polarity is important.

If you have +12V on the inner pins relative to the board-edge pins, and you still don't have the green light coming on when everything else is unplugged, then it's very curious indeed. Especially if that happens on two different boards!

[dlw]

Well, well... with the old mainboard installed with the original power supply: the light is green.
The new power supply only shows .15vdc on the 20vdc setting and 1 on the 200vdc setting.

[RetireeJay]

Are you aware of the need for a jumper to make an ATX supply come alive?

On that big connector in the third picture you posted on the 5th, you need to jumper the green wire to any nearby black wire. This is how ATX supplies can be controlled by software: when you press the "on" button on your desktop, you temporarily connect the black and green wires, which then get connected steadily by a software controlled switch; when you tell your desktop computer to shut down, it breaks the connection between the green and black wires.

[dlw]

Purchased the jumper from Printrbot that was suggested. There is no green wire on it. No, I did not know about the green wire.

The printer is working for the moment with original parts.
However, when using Cura to level the bed, clicking up and down work opposite.
Click up, Z goes down. Click down, Z goes up.

Attached are a photo of the wiring diagram for 'Simple' and a photo of the actual wiring.
I traced leads X, Y, Z and E. They are correctly installed as per the diagram.
The colors are correct.
All that is different is the cable to the power connection. It on has 2 wires, red and black.
The Z stop connecting wire are different colors.

[RetireeJay]

Even though you have followed the instructions for plugging in the Z motor connector correctly, your motor is still running in the wrong direction. Just unplug the connector from the board, turn it around, and plug it back in with the blue wire where the EDIT: red (green according to the diagram but not the photo) one was, etc. That will fix the direction of the motor.

The green wire on the big ATX connector is part of the power supply. It has to be connected to ground to make the ATX supply come on. This is completely separate from the jumper needed to connect the 12V power to the board.

smATX Connector green wire jumpered.jpg

[dlw]

I am about ready to throw this thing out in the yard.
Now, When clicking 'Resume', the the Z motor keeps running to the top and stalls.
Makes a fairly noisy grinding noise.

Also, the color of the wires on my unit do not match those of Printrbot's diagram.
When turning over the Z connector, blue does not replace green, it replaces red. No idea what this means.

Will try and make green jumper.

[RetireeJay]

Also, the color of the wires on my unit do not match those of Printrbot's diagram.
When turning over the Z connector, blue does not replace green, it replaces red. No idea what this means.

Don't worry about that. The electrons don't care what color the insulation on the wire is.

However, when using Cura to level the bed, clicking up and down work opposite.
Click up, Z goes down. Click down, Z goes up.

HOLY COW!!! I JUST CHECKED OUT CURA "BED LEVELING" ON MY PRINTER AND I REALIZED THAT THE CURA PROGRAM, BUILT ORIGINALLY FOR ULTIMAKER PRINTERS, ASSUMES THAT THE BED MOVES UP AND DOWN, NOT THE PRINTHEAD!!! SO WHEN THEY SAY "UP" THEY REALLY MEAN "DECREASE THE SPACE BETWEEN THE PRINTHEAD AND THE BED" - WHICH ON A PRINTRBOT IS A "DOWN" MOTION!

So... I was wrong to say reverse the motor plug. It was OK to begin with. Please return it to the previous state.

[dlw]

OK, jumper is installed as is the 400 watt power supply.
Corrected Z lead.
Trying to print.
After extruder heats up, there is smoke. Probably because printer is not printing.
Cura says it is printing on com 9.
Device manager list an unknown device.
Trying to find if 9 is correct port. Or, which port is.

[RetireeJay]

If Cura finds the printer and can control it, then you're good. It seems that the port number assigned to the printer by your computer's Operating System can be somewhat arbitrary, but that doesn't matter. My port is 30, even though there's nothing occupying numbers between 5 and 29! But it works just fine.

Yikes! Smoke!

I'm guessing the smoke is coming from the Hot End? What does Cura report for the temperature of the Hot End? It should not go over your setpoint by more than a few degrees at most; for example if your setpoint is 210 then any temperature above 220 would indicate a significant problem with the temperature control. Similarly for the heated bed; if you have the setpoint at 70 then it should never go above 80 or so. If either of your temperatures it totally uncontrolled - just going up and up - then either there's a short or a bad component on your board.

If the temperatures are in normal range and properly controlled, then maybe the smoke is just some kind of contamination that's getting burned off. Normal PLA, ABS, or other plastics don't smoke at the correct printing temperature, even if they are sitting in the nozzle for a while without printing. But PLA can "char" or become hardened and create a jam; don't let it sit in the nozzle at printing temperature for a long time without moving.

[dlw]

Extruder temp is set at 208. Cura reports 190 and didn't go higher.
Currently:
No smoke, extruder is hot, 190, I guess.
When running the leveling setup, when I click on 'Resume': the printer halts and remains there.
I think the smoke came from leftover filament in the extruder.

[dlw]

Forgot:
Clicking on 'Finish', a dialog box opens prompting me to print.
Click on 'Print', and nothing happens with the printer even though it is supposedly printing on com 8.

[RetireeJay]

If the extruder temperature is supposed to be 208 and it's actually only at 190, then the printer is going to wait "forever" for the extruder to reach the setpoint temperature. The print won't start until it's been stable at setpoint for 10 seconds. That's because the default G-code for setting the Hot End temperature includes a provision to "wait for the Hot End to reach temperature before proceeding".

If you have a fan cooling the extruder heatsink, check the orientation of the fan to make sure no part of the airflow is blowing directly on the hot part of the extruder. It's amazing how much some blown air can suck away the heat.

If Cura is communicating with the printer at all, don't even think about what port you're on. It may be 8, it may be 9, it may be 29; no matter. If you have communication, you're good to go.

[dlw]

Improvement; extruder up to 191.... then stalls.
Fan never comes on.
Starts smoking after a while.
No filament to melt since it is not feeding filament.
Smells very hot.

[Mooselake]

What happens if you set the print temperature to, say, 185?

I don't see any mention here of which hot end you're using and don't remember if you posted it elsewhere. You didn't switch to an E3D, which uses a different thermistor, did you? Is the thermistor making good contact with the heat block or coil (depending on hot end type)?

Kirk

[RetireeJay]

I'm with Kirk here. It sounds like your thermistor may not be in good contact with the heated part of the Hot End. If you have no fan running, there should be more than enough power to carry the actual temperature of your Hot End well beyond 250C. But if your thermistor is hanging loose off to the side, it won't know how hot the Hot End actually is.

[dlw]

I quit... for a while.
Can't even get Cura to recognize the damn thing now.
When trying to run Bed Leveling Wizard, Cura can not find the printer.
I've unplugged and replugged the power supply, power cable, USB cable. Restarted Cura.
The leads at the the hot end are all connected.
The last time it ran, the filament broke into about an inch or so above the extruder. I think its plugged.
I gonna go look for a tutorial on how to clean the extruder.
See y'all later.

[dlw]

Same as above, no change.
If anyone wants it, pay freight from 98601 plus something if possible.
Includes 400 watt power supply.
Checking with Printrbot for shipping weight now.

[dlw]

I do not know what else to do.
It has power, green light.
It is wired properly.
Cura will not find it.
I will not put any more money into it. Already bought one main board.

Any suggestions welcome.

[dlw]

OK, the printer is working... part time.
In Cura, a 'Printing on COM8' opens and reads 'Opening serial port' and stops.
Does nothing else.

Opening 'Devices and Printers', the printer is listed and says it is OK.
Tried every COM port and BAUD rate listed in Cura.

However, it just stalls at this point.

Any help on solving this is appreciated.

dlw

[Mooselake]

Can you use the device manager to determine which port? Unplug the USB cable, open the device manager, plug it back in, and see which new COM port appears.

The port speed (so called baud rate) doesn't matter. The Printrboard's MCU has onboard USB com port emulation and runs at USB speeds while ignoring the configured rate.

Pre windows 10 you might need to install the com port "driver"

Kirk

[dlw]

Port 8

Still stalls at 'Opening serial port'.

[RetireeJay]

In desperation, you can try a different program than Cura just to try to debug where the problem lies.
The very most basic possible debugging tool is a terminal emulator called "PUTTY". You won't use it to control your printer, and it does have some setup steps to get it working right, but it can prove whether or not you have communication with the board.
Read this thread, noting especially the setup steps needed to make PUTTY work.
viewtopic.php?f=18&t=4602&p=30392&hilit=putty#p30392

[dlw]

I would rather use Slicer with Ubuntu. Trying to figure it out now.

What I do not understand with Cura is; why Cura will go through the extruder adjustment, then freeze.
There has to be a connection between Cura and the printer to make the extruder adjustments.

dlw

[Mooselake]

Post your startup g code, or copy the beginning of a gcode file and post here (use the code button in the advanced editor, or [ code ] stuff [ / code ] (less the extra spaces) if you're using a mobile and don't have the pushbuttons). It's possible you're waiting for something that isn't there. Is your bed thermistor reading room or your set temp, or could it be disconnected or shorted?

Kirk

[dlw]

;Sliced at: {day} {date} {time}
;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}
;Print time: {print_time}
;Filament used: {filament_amount}m {filament_weight}g
;Filament cost: {filament_cost}
;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line
;M109 S{print_temperature} ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
G1 Z15.0 F{travel_speed} ;move the platform down 15mm
G92 E0 ;zero the extruded length
G1 F200 E3 ;extrude 3mm of feed stock
G92 E0 ;zero the extruded length again
G1 F{travel_speed}
;Put printing message on LCD screen
M117 Printing...

The bed gets so hot after a while you can not touch it. I turn it off quickly.


gcode.txt

[Mooselake]

From looking at your previous pictures, did you put the bed heater circuit board on top of the aluminum bed? I don't have a SM (or any other simple), but doesn't the heater belong underneath the aluminum bed? Can somebody with one of these comment?

Do you get what seem to be accurate bed temperature readings from Cura?

Can you post the same gcode from the file you're trying to print, so we can see both what's being filled in, and what extras your slicer is generating. Just down to the first few lines of actual print moves. I'm wondering if it's waiting for the bed (or something else) to come up to temp. Also, what are you setting your print bed temperature to?

Kirk

[dlw]

That is the g code.
Extruder temp is 200
Bed temp is 60
No aluminum bed, stock Printrbot.
Heat bed on top, thermistor underneath.

Shouldn't the g code be filled in?
When a model is first loaded, it takes an nth of a second for it to appear.
Isn't that when it gets sliced?

[RetireeJay]

In Cura, after you load the STL file, the display of the object changes color a couple of times and then it displays the printing time and quantity of filament. That means it has sliced the object. If you don't see a printing time and quantity, then has Cura refused to slice the object because it finds some fault in the file (like the object would not fit inside the print volume it expects).

If you want to see the actual G-code that will be used to print the object, I think you have to go to File -> Save GCode, and then open up the saved file in a text editor. At that point, you should have no curly brackets in the code. Here's an example. It shows you in a generic way what the G-Code should look like. It's kinda random (like a 0.6 layer height!) but that's because I never actually use Cura for printing. I use Slic3r and Repetier Host. This example includes the first line of actual printing, like Mooselake requested.

Code: Select all

M190 S70.000000
M109 S220.000000
;Sliced at: Wed 26-04-2017 16:16:38
;Basic settings: Layer height: 0.6 Walls: 2.4 Fill: 100
;Print time: 15 minutes
;Filament used: 0.681m 5.0g
;Filament cost: None
;M190 S70 ;Uncomment to add your own bed temperature line
;M109 S220 ;Uncomment to add your own temperature line
G21        ;metric values
G90        ;absolute positioning
M82        ;set extruder to absolute mode
;M107       ;start with the fan off
;G28 X0 Y0  ;move X/Y to min endstops
;G28 Z0     ;move Z to min endstops
;G1 Z15.0 F9000 ;move the platform down 15mm
G92 E0                  ;zero the extruded length
;G1 F200 E3              ;extrude 3mm of feed stock
;G92 E0                  ;zero the extruded length again
G1 F9000
;Put printing message on LCD screen
;M117 Printing...

;Layer count: 153
;LAYER:0
M107
G0 F9000 X83.878 Y83.141 Z0.600
;TYPE:SKIRT
G1 F1200 X84.552 Y82.550 E0.06253

[dlw]

M190 S70.000000
M109 S210.000000
;Sliced at: Wed 26-04-2017 13:51:46
;Basic settings: Layer height: 0.25 Walls: 0.8 Fill: 20
;Print time: 33 minutes
;Filament used: 1.919m 5.0g
;Filament cost: None
;M190 S70 ;Uncomment to add your own bed temperature line
;M109 S210 ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
G1 Z15.0 F9000 ;move the platform down 15mm
G92 E0 ;zero the extruded length
G1 F200 E3 ;extrude 3mm of feed stock
G92 E0 ;zero the extruded length again
G1 F9000
;Put printing message on LCD screen
M117 Printing...

[dlw]

;Layer count: 39
;LAYER:0
M107
G0 F9000 X54.508 Y54.124 Z0.300
;TYPE:SKIRT
G1 F1200 X55.323 Y53.531 E0.05028

Sorry, I missed a few lines

[RetireeJay]

The M190 command tells the printer to wait until the bed has reached setpoint temperature. M140 would set the bed temperature and immediately proceed with the next steps in the code (regardless of bed temperature).

Heat bed on top, thermistor underneath.

Is the thermistor in contact with the bottom of the bed heater, or is there something in between so the thermistor reading lags behind the actual temperature? You say the bed gets so hot you can't touch it. Is that high heat also indicated in the Cura/Pronterface display? If it thinks the bed is still below setpoint, it will keep on sending power to the bed and keep on waiting until the bed reaches setpoint temperature. OTOH, if it thinks the bed is too hot, it will also go into a wait state for the bed to cool down. If somehow your board is unable to control the power to the bed, delivering full power all the time, you'll never get past the M109.

[dlw]

The distance between the thermistor and bed might be a half a mm.
Read where you suggested 'gouging' the bed but I'm a little skeptical to take the Dremel to it.
So, do you think 'gouging' would help solve the problem?

[RetireeJay]

We have a lot of unanswered questions here before resorting to the Dremel. Let's identify the problem more precisely before we start implementing solutions. Are we sure that the hangup is due to waiting for bed temperature to stabilize? Does the thermistor agree with your subjective opinion of bed temperature?

[dlw]

When it worked... No.
The extruder read 199.
The bed 21. Probably ambient temperature.
Printed a couple of small items, one turned out decent, the other had several problems.

[dlw]

I have no choice. I'm going to abandon the Printrbot.
Buy a kit of some kind. Rob the Printrbot parts.
Get a different main board.
Doing the research now.

Thanks for all your efforts.

dlw