First, I'm a noob, I bought a reprap mendel prusa off craiglist a couple days ago. Did sprinter, pronterface and using slic3r. So far, I've got everything running and calibrated all the axis, but i'm having trouble getting the print to adhere to the glass plate. I have ABS judging by the sooty flame when I light it. (great test btw to tell ABS from PLA). I've looked and most people suggest kapton tape for ABS. so I ordered some, it will be here tomorrow. I'll be using hairspray on the glass for tonight's attempt. :) The issue I'm having is with my heated bed (MK1). The temperature is only going up to 70C. From what I read it should be 110C. I added some cardboard insulation to the bottom of the heated board to help, but I think my main problem is my power supply. Its at 350 Watt converted computer supply. It puts out 12Volts, but when I have the extruder heater on and the bed heater on it drops to 10.6Volts. I'm thinking my power supply doesn't have the juice. I have another AC/DC converter that outputs 12Volts, 4Amps. My question is can I hook them both up at the same time to the same terminals on my Sanguinololu to supply more amps? Let me know what you think. I know if it was batteries it would be OK, but with power supplies I'm not sure. https://reprap.org/forum/read.php?4,269923,269923#msg-269923 Thu, 14 May 2026 18:12:13 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?4,269923,272990#msg-272990 https://reprap.org/forum/read.php?4,269923,272990#msg-272990 That will teach me to try to reply while doing four other things at once. 8-)]]> BlackDragon Reprappers Wed, 27 Nov 2013 17:57:37 -0500 https://reprap.org/forum/read.php?4,269923,272963#msg-272963 https://reprap.org/forum/read.php?4,269923,272963#msg-272963 sheck626 Reprappers Wed, 27 Nov 2013 16:51:43 -0500 https://reprap.org/forum/read.php?4,269923,272396#msg-272396 https://reprap.org/forum/read.php?4,269923,272396#msg-272396 Maxx Mayhem Reprappers Tue, 26 Nov 2013 17:36:53 -0500 https://reprap.org/forum/read.php?4,269923,272365#msg-272365 https://reprap.org/forum/read.php?4,269923,272365#msg-272365
Look at the OP's description. He's using a 350W power supply. Almost everything I've read says you need 400W or better. Most folks user 450W or better. So he's already at a deficit. Trying to force a 350 to generate 400+ watts of power is a fire waiting to happen.

However, I've seen several solutions, that are all very safe.
1. Get the correct sized power supply. Uncle_Bob, FTW.
2. Use a second power supply. - yes, this can be done. If you move the heatbed off the controller board, and run it independently, then the 350 has enough power for the printhead and motors. Just configure your software to run like there is no heatbed. If you need some measure of temperature control, you could install a rheostat on the heatbed. It's fuggly, but it would work.

My recommendation, to keep the control and eliminate the fire hazard, get the new power supply. You'll be glad you did.

Oh, and make sure that you are plugging into an outlet rated for that power. (you won't get 30A of power from a 15A house circuit) ;)]]> BlackDragon Reprappers Tue, 26 Nov 2013 16:27:50 -0500 https://reprap.org/forum/read.php?4,269923,270336#msg-270336 https://reprap.org/forum/read.php?4,269923,270336#msg-270336 nophead Reprappers Thu, 21 Nov 2013 17:13:34 -0500 https://reprap.org/forum/read.php?4,269923,270329#msg-270329 https://reprap.org/forum/read.php?4,269923,270329#msg-270329 uncle_bob Reprappers Thu, 21 Nov 2013 16:57:37 -0500 https://reprap.org/forum/read.php?4,269923,270277#msg-270277 https://reprap.org/forum/read.php?4,269923,270277#msg-270277 sheck626 Reprappers Thu, 21 Nov 2013 15:12:41 -0500 https://reprap.org/forum/read.php?4,269923,270262#msg-270262 https://reprap.org/forum/read.php?4,269923,270262#msg-270262
Without drawing current the 0.1 Ohms between them should reduce weird things like overregulating or 'wobbling' because of wrong input-currents ...]]> VDX Reprappers Thu, 21 Nov 2013 14:35:34 -0500 https://reprap.org/forum/read.php?4,269923,269943#msg-269943 https://reprap.org/forum/read.php?4,269923,269943#msg-269943
The more detailed answer is that they are not adjustable for output. Which ever one is running the slightly higher voltage will put out all the current. You can't tweak them to be the same output voltage. If you could then a pair of low value resistors might help you share the current. More likely you still would have one hog all the current.

Better solution, use one for the 11A supply, use the other for the 5A input.

Best solution - spend $44 or so on a proper industrial 12V 30A supply.]]> uncle_bob Reprappers Wed, 20 Nov 2013 20:09:55 -0500 https://reprap.org/forum/read.php?4,269923,269928#msg-269928 https://reprap.org/forum/read.php?4,269923,269928#msg-269928 sciome Reprappers Wed, 20 Nov 2013 18:57:14 -0500 https://reprap.org/forum/read.php?4,269923,269925#msg-269925 https://reprap.org/forum/read.php?4,269923,269925#msg-269925 VDX Reprappers Wed, 20 Nov 2013 18:47:32 -0500 https://reprap.org/forum/read.php?4,269923,269923#msg-269923 https://reprap.org/forum/read.php?4,269923,269923#msg-269923
So far, I've got everything running and calibrated all the axis, but i'm having trouble getting the print to adhere to the glass plate. I have ABS judging by the sooty flame when I light it. (great test btw to tell ABS from PLA).

I've looked and most people suggest kapton tape for ABS. so I ordered some, it will be here tomorrow. I'll be using hairspray on the glass for tonight's attempt. :)

The issue I'm having is with my heated bed (MK1). The temperature is only going up to 70C. From what I read it should be 110C. I added some cardboard insulation to the bottom of the heated board to help, but I think my main problem is my power supply. Its at 350 Watt converted computer supply. It puts out 12Volts, but when I have the extruder heater on and the bed heater on it drops to 10.6Volts. I'm thinking my power supply doesn't have the juice.

I have another AC/DC converter that outputs 12Volts, 4Amps. My question is can I hook them both up at the same time to the same terminals on my Sanguinololu to supply more amps? Let me know what you think. I know if it was batteries it would be OK, but with power supplies I'm not sure.]]> sciome Reprappers Wed, 20 Nov 2013 18:30:53 -0500