folger tech heat bed will not breach 98 c

how can I get the temp higher for this bed.. is there something I need to update in the firmware..using most up to date marlin. and cura

Did you check to make sure that you have your max bed temp in marlin and rep host is higher than 98? If you did, then make sure that you have soldered your heated bed properly. There are a pair of contacts that need to be bridged in order to reach higher temps.

both of that is done..i have 12.2v at the bed on ..

It might be hard to get past that temp if you do not insulate the bed.

I have been following the folgertech 2020 kossel thread in the delta forum, and some of the people there describe similar problems and solved it by insulating the bed by using something like cork, wood and/or mufflerbandage.

Hi,

Check your wires from the board to the bed, especialy soldering.
You need strong contact points.

Through, the PSU is chinese. Check if it delivers the right amperage.

The down side bed insulation helps the bed temperature to rise quicker.
But you should be able to reach at last 105°C with a simple bed.

Last, adjust your PID setting for the bed.

++JM

Edited 2 time(s). Last edit at 08/25/2015 07:34AM by J-Max.

If he gets 12.2 volts on the heat bed, adequate amperage is a given . . . if the PS could not supply it, the voltage could not stay up - basic physics . . .

- Tim

Edited 1 time(s). Last edit at 08/25/2015 02:18PM by tadawson.

I'm maxing out at 103 c with cork insulation under the bed.. settings in marlin are maxed out from my understanding and research (but I could be wrong)..

@tim...im going to have to disagree with you..voltage does not equal amperage or vice versa...although I will do my best to check that..what should the amperage be?

The amperage should be around 9-10A, depending on the heated bed resistance. If you own a DVM that can meter <1 ohm you can check if it's below 1.5 Ohms.

The same can be checked for the wiring and soldering, if there's a voltage drop from the solder joints to the 12V connector you'll loose power.

The higher the voltage, the less wiring will have an effect on the amount of power that can be put into the heater. It's recommended to use 1.5mm diameter wire like loudspeaker wire, or even better use very thin multi strand wire used for RC cars with silicone coating. Very low resistance and very flexible.

The best way to improve heating time and reaching higher temperature is to use a 24V PSU instead. My i3 can reach 110 degrees C in under 4 minutes, 140 degrees in 10. You don't need insulation either, saves weight and hessle. Just get a 24V 15A PSU. If you have a 12V heated bed only, that's no problem either, use the firmware PWM function to lower the total current draw just under 11A. If you know the heated bed resistance you can calculate what duty cycle you'll need to be under the 11A thermo fuse tripping point. I've been running a 12V heated bed on a 24V for a couple of months without issues so far.

Most RAMPS 1.4 are 24V compatible, you just need the PSU on the 11A terminal and adjust the firmware and you're done

I do have a dvm...I have a .2 volt loss from the ramps board to the heated bed..I'm currently using 16 gauge wire and I was going to drop it to 12 gauge this evening.. The bed I have is an mk2b (I think that's correct) and its either 12 or 24v...now as for the other stuff you wrote about...seems too far fetched for me to achieve without a little bit more of a description..

If the room temperature is chilly or there are drafts I wouldn't be surprised to see a PCB bed top out at 100c. I cranked the potentiometer on my power supply to 14V and put insulation on the bottom. Before it would take a really long time to hit 105c and now I can get 110 or 120 pretty quickly.

The fan was really loud at 14V so I put it on a pwm channel at 80% duty cycle.

Edited 1 time(s). Last edit at 08/26/2015 02:57PM by 691175002.

Even better, move the 12v wire to 24v pad on the mk2b and add a 24v psu to the 11Amps terminal, no changes in firmware needed. It may be a good idea to enable pid for the heated bed and run a self calibration command. Search the wiki for instructions.