satman49 wrote:

Probably a silly question ,but can the bed be powered by external sourse? If so how would you regulate the temperature?

You can easily take the current bed output and feed it into a relay/SSR then pipe independent power into the relay to be switched to the bed, this leaves the stock pid controller in charge of maintaining temperature while using a separate power supply.

That's kind of how I have mine set up.  Different Heat Pad so my external source is AC but the SSR switches it on and off per the output of the board.  Takes a little tuning but heats up super fast.  My motivation was to remove the load from the board and stock power supply.  Before all my new stuff arrived I actually ran my stock bed with a standard 12v relay and a separate 12V supply and it definitely worked better than stock.  It was a cheap test to perform using a $6 automotive relay and a motor cycle battery as the power supply.  All stuff I had laying around.

Probably a silly question ,but can the bed be powered by external sourse? If so how would you regulate the temperature?

You can easily take the current bed output and feed it into a relay/SSR then pipe independent power into the relay to be switched to the bed, this leaves the stock pid controller in charge of maintaining temperature while using a separate power supply.

Probably a silly question ,but can the bed be powered by external sourse? If so how would you regulate the temperature?

Yes, but then you would have to use another system to regulate it . Probably a PID controller box, since those are widely available for $15-22.  But you still want to run the same voltage to it, not AC.

I had the exact same problem few months ago, bed would only heat up to about 50°C and not any further.  In my case, it was the bed heater.  I replaced it with a QU-BD and never looked back.

Here is a quick check to eliminate the faulty wiring (I assume the extruder heater is working OK, because he said he can print stuff).

Swap the bed heater and Extruder heater wiring on the board. Then in RH click the extruder heater.  Since the bed is now plug in the extruder heater connector, it should start heating the bed.  You should see the temp climb up on the bed heater.

If there's nothing wrong with the bed, it should warm up to 90-100°C. Turn it off manually.  You don't want to leave it on, becuase the thermal cut-off won't work correctly with the heater bed plugged into the extruder connector.

At least this will tell you if your bed heater is good or bad. 

Good luck.

P.S. don't forget to put everything back to normal after the test.

Sorry I didn't read closely.

Why are you apologizing?  You had a valid thought.

The circle is complete because we are back to the first response from me that suggested a bad connection or short with the thermistor.

simmunity wrote:

Since new my Solidoodle 3 bed wont get up to 105C or even close.  Not sure why. Voltage at the board input stays at or above 12 volts.  When in manual mode on Repetier, when I try to get the bed to a high temperature, it gets to around 50c, then turns off both extruder and bed heater after a couple of minutes.  This has been going on since I bought it around this time last year, got frustrated, put in on the shelf, but I need to use it now.  Prints were warping and popping off.  Why would the bed heater not get to 105C.  I need to make an enclosure, but that won't fix the bed heater problem.  Is this a common issue?  Is it a defective heater or control board?  Any ideas?

Assuming you don't have an issue with your PC (sleep mode kicking in) You most likely have a bad connection or a short on one of the thermistors.  What errors is R-H showing when this happens?

And the circle is complete

The thermistor connection is most likely loose maybe among other things. I would check the temperature log in RH and see if the temp for the bed or hotend ever got outside of it's temp range. (<3C or >215C for extruder , <3C or >115C for bed) A loose connection will read below 3C causing an emergency shut off and going above the top end for the extruder or bed will also cause the emergency shut off.

I don't know what the top end limit for the extruder is any more. They may have bumped it up since I have had to deal with it.

This.

We are working on replacing the current wiring set up.

^With respect to what Ronsii said:

I personally have an older SD2, so mine was just an aluminum resistor. Yours can be a pad. I dont know how common the problem would be with the pad. But all you have to do is measure the resistance of it. This can be done without taking apart the bed.

Why would bad resistance throw a M999?

I personally have an older SD2, so mine was just an aluminum resistor. Yours can be a pad. I dont know how common the problem would be with the pad. But all you have to do is measure the resistance of it. This can be done without taking apart the bed.

I have seen heating pads made like this for other kits but I am not sure if the SD ones are made this way... as I haven't had any of mine fail(yet ) so no heating pad postmortem...

I should note, my heater didn't fail until after about 13 months of running it near 90C.

Eventually I replaced the whole shebam with 2.4 ohms of nichrome wire. I applied two layers of thin kapton, added my wire in a zipzag form, then two layers of kapton, then a layer of aluminum (to reflect), then more kapton, then the standard insulation.

Regards

I guess my minor agitation is that I've spent many hours fiddling with this machine, had to align the carriage after shipping, had to figure out that I need to use an acetone and ABS slurry on the kapton bed to get adhesion, and other unstated but essential details to get it to work at all.  Their web site and PR conveys a different image leading me to expect it to just work only to find out it is like my IMSAI 8080 computer from 1976, a very early product and design that is in its infancy still and not really consumer ready.  I am fine with that as an engineer, but just sayin...

I wish Solidoodle made an enclosure kit, but can make something pretty myself, as that seems critical to making larger prints.  The rest seems like it is just an electrical problem that I have to fix.  Again thanks for the support :-)