I’m getting very close to completing the MP3DP V2 using hardware from the V1 I bought a year ago.
I have finished the main construction and was getting ready to mount the bed (Dual power Mk3) but the previous owner mounted/glued a piece of glass to the BOTTOM of the heater, which covered the side hole I need to use for mounting. It also shows 2.9 Ohms across the 12V connections which, if I understand correctly, is not low enough to get the bed very warm.
So I need a new bed, but Ryan is out of them at the moment. I’ve been looking online but am hesitant to get any of the ones on Amazon, and RepRap is out too.
I’m open for suggestions for suppliers you have used and had a good experience (other than Ryan).
It sounds like you are on the 24v connections, you should have ~1.4ohm across the 12v. connections 2 & 3 should be shorted together for 12v operation.
Looking at aliexpress there seems to be more than one design for the Mk3 dual power - at least one with pads for a central thermister and one without so careful examination of the advert pre-purchase would be a must!..other than that I would suggest they are all of comparable quality - I have had mk2a’s in the past that resembled a banana and others that were perfectly flat, but never had one that didn’t work.
Tried to sleep last night but was a bit distracted by the bed situation. I finally got up and measured the resistance between connection 1 and the combined connections 2 and 3. Bingo! The resistance was 1.6 ohms. At the high end of the stated range (1.2-1.6) but it should still work.
I then took a good look at the clear "glass that appeared to be glued to the bottom of the aluminum plate (and it had obviously been printed on in the past) and saw that it wasn’t glass as I thought, but rather acetate. I was able to separate it from the plate without any damage to the plate, but it took a while to get all the glue off the plate.
I soldered back the power wires and temporarily installed the thermistor. Hooked it all up to the RAMPS board and got heat. I didn’t let it go all the way to 65 degrees but it was obviously getting hot.
In any case it looks like I have a functional heated bed. Dodged that bullet.
Now I can get back to mounting the bed to the speed Y-plate.