1 Topic by megatron

  • megatron
  • Member
  • Offline
  • Registered: 2016-04-20
  • Posts: 47

Topic: 3DGreat Heated bed w/ Marlin?

Hey all. I've been using a 3DGreat heatbed but can't seem to get the onboard thermistor to read, forcing me to use an external thermistor. However that solution has been cumbersome and I now need to condense my temp reading hardware.

The thermistor tables in Marlin are reporting all over the place, ranging from -100c to as high as 1200c.

This leads to my question; Is anyone else using this board in Marlin, sprinter, ect. and if so, what are you doing to get the onboard thermistor to play nice?

2 Reply by jagowilson

  • jagowilson
  • PRINTiT
  • Offline
  • Registered: 2014-09-14
  • Posts: 1,701

Re: 3DGreat Heated bed w/ Marlin?

I can't find any info on that bed from the keywords you've provided. Can you give a product link please?

3 Reply by megatron

  • megatron
  • Member
  • Offline
  • Registered: 2016-04-20
  • Posts: 47

Re: 3DGreat Heated bed w/ Marlin?

Here it is.

https://www.aliexpress.com/item-img/Fre … 70948.html

4 Reply by carl_m1968

  • carl_m1968
  • carl_m1968
  • Member
  • Offline
  • From: Far North almost not Dallas
  • Registered: 2014-10-17
  • Posts: 6,512

Re: 3DGreat Heated bed w/ Marlin?

That bed is made for an Ultimaker. They do not use a standard thermistor on their bed. I had a clone and had so much trouble converting it that I finally bought a standard 100K thermistor and glued/taped it to the bottom of the board and wired it into my new board.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

5 Reply by jagowilson (edited by jagowilson 2017-05-23 22:57:14)

  • jagowilson
  • PRINTiT
  • Offline
  • Registered: 2014-09-14
  • Posts: 1,701

Re: 3DGreat Heated bed w/ Marlin?

Is it still a thermistor, though, obeying Steinhart-Hart? If so, we can build a rough thermistor table from the Beta values in the datasheet. It will be accurate enough for a heat bed. Carl, can you provide any model numbers for the thermistor you had?

I can find absolutely 0 information about this 3DGreat bed. The website has no English translation. http://www.3dgreat.com.

6 Reply by carl_m1968

  • carl_m1968
  • carl_m1968
  • Member
  • Offline
  • From: Far North almost not Dallas
  • Registered: 2014-10-17
  • Posts: 6,512

Re: 3DGreat Heated bed w/ Marlin?

jagowilson wrote:

Is it still a thermistor, though, obeying Steinhart-Hart? If so, we can build a rough thermistor table from the Beta values in the datasheet. It will be accurate enough for a heat bed. Carl, can you provide any model numbers for the thermistor you had?

I can find absolutely 0 information about this 3DGreat bed. The website has no English translation. http://www.3dgreat.com.

Mine was just an ordinary 100k thermistor I bought off ebay. If you mean the one that was on the bed it was measuring 59K at room temp. That's all I know and no matter what existing table I tried in Marlin it would not work right.

My printer was a CTC dual which is a copy of Makerbots and Ultimakers.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

7 Reply by jagowilson (edited by jagowilson 2017-05-24 01:24:37)

  • jagowilson
  • PRINTiT
  • Offline
  • Registered: 2014-09-14
  • Posts: 1,701

Re: 3DGreat Heated bed w/ Marlin?

Interesting. Yeah, that likely won't be an existing table. The good news is one can be created but I really can't help any further until I have a datasheet with a beta value and/or a temperature-resistance table. Give me these values and i'll see what it takes to generate such a table for Marlin.

So OP given that it's likely a common thermistor used by Ultimaker, maybe you can use that information to get a model number and/or datasheet for the thermistor.

8 Reply by megatron

  • megatron
  • Member
  • Offline
  • Registered: 2016-04-20
  • Posts: 47

Re: 3DGreat Heated bed w/ Marlin?

I'll pull it from my machine and see if the chip on the underside has any info.

9 Reply by jagowilson (edited by jagowilson 2017-05-26 21:18:33)

  • jagowilson
  • PRINTiT
  • Offline
  • Registered: 2014-09-14
  • Posts: 1,701

Re: 3DGreat Heated bed w/ Marlin?

No problem. Let me know. I did some basic research and there's a chance that it's not a thermistor, but rather a thermocouple. If that's the case you'll need an external amplifier to use it...

10 Reply by colcred

  • colcred
  • Newbie
  • Offline
  • Registered: 2017-05-29
  • Posts: 1

Re: 3DGreat Heated bed w/ Marlin?

Hi, Recently bought used Ultimaker Original updated with 3DGreat heated bed, all was working great until I foolishly updated the program (I couldn't resist) now I get Err:MAXTEMP BED, I notice the bed temperature is now showing H100/0degreese, I'm sure it used to show the now temperature first and the maximum afterwards. can anyone help?
Thank you.

11 Reply by megatron (edited by megatron 2017-05-31 20:47:46)

  • megatron
  • Member
  • Offline
  • Registered: 2016-04-20
  • Posts: 47

Re: 3DGreat Heated bed w/ Marlin?

jagowilson wrote:

No problem. Let me know. I did some basic research and there's a chance that it's not a thermistor, but rather a thermocouple. If that's the case you'll need an external amplifier to use it...


That is in fact the case with this bed. I've seen people use thermocouples on other opensource designs with some success so I'll be starting there. As to the type of thermocouple it is, I can't say, but after speaking with the manufacturer, I have a better idea on which route to take.

colcred wrote:

Hi, Recently bought used Ultimaker Original updated with 3DGreat heated bed, all was working great until I foolishly updated the program (I couldn't resist) now I get Err:MAXTEMP BED, I notice the bed temperature is now showing H100/0degreese, I'm sure it used to show the now temperature first and the maximum afterwards. can anyone help?
Thank you.

As for your post - DO NOT hijack threads by piggybacking your issue - there is plenty of space on the forums for firmware related issues and I suggest you start your own thread, or better still, looking for a thread that has solved your specific issue.

12 Reply by GunterO

  • GunterO
  • Newbie
  • Offline
  • Registered: 2017-08-18
  • Posts: 1

Re: 3DGreat Heated bed w/ Marlin?

Hello, just some info. I bought this one:
https://www.aliexpress.com/item/Ultimak … 0.0.pIXCGH
Looks identical. and the thermistor is just a 100k general version. So no tweaks needed there, and it works perfectly.
I used this for the build: https://www.instructables.com/id/Ultima … d-Upgrade/