MK2 Heat Bed Wiring- stand alone

I've had a CubeX for about 9 months because I didn't think I had the skill to build my own and I wanted a huge build volume. I enjoyed more success with the prints than most have, I got lucky from what I read. Since then I've abandoned their material cartridges and their slicing software for standard/much cheaper Printrbot material, etc, and I'm using KISSlicer software and it's a whole lot better. I'd like to start printing reliably with ABS now which of course means I need a heated print bed so...

I bought a MK2 heat bed, a Power Supply, thermistor, 1k resistor, led's, and 12 ga braided pfte wire. My problem is that the only wiring diagrams I've found are for RAMBo boards that run the rest of the printer. What I need is just a stand-alone heated bed, correct? CubeX's don't have the ability to control a heated bed with software/bfb files, and I don't need it to turn on/off automatically (maybe down the road), I just need it to heat up to certain temp. Can that be achieved without the Arduino board, which I have from another project, or is that necessary to control the temp? I've been working on this for a few weeks with little progress and any diagrams, pics, instructions would be awesome.

Thanks for the help

nissin

You need some sort of electronics to:

1) Read the thermidor temperature
2) Set a control point for the bed
3) Adjust the power into the bed to hold that control point.

There are some pretty good > $40stand alone solutions to do this with various temperature sensors. A Mega + Ramps will run about $40. The Ramps / Mega will run with the parts you already have. The stand alone gizmo probably won't like your thermistor.

An added benefit, the Ramps understands gcode and you can move the heated bed temperature up and down as you print. That's not going to happen with a stand alone PID box.

Well, I don't exactly have anything 'stand alone' operational or even close, just a group of parts. If I go the mega+ramps route, will that run separately from my Cubex board or would that completely replace it? Ideally, I'd like to have it run separately, but if replacing the board is as easy as unplugging the motors/hotends/sensors/etc and plugging them back into the new one, I'd entertain that plan. Here's an example of a unit that has the temp set independently from the gcode file [shop.grmproducts.com], although it's super expensive.

I've done searches for this type of thing, or even a sensible wiring diagram, and I've turned up with very little. Does anyone know of a good blog/post that explains some options or methods for a heated bed without running through the main printer board?

Thanks for the help,

nissin

Do you want to manually change the heated bed temperature as the print progresses? Normally you start at one temperature for the first layer and then switch to another temperature after that It's also common to turn off the bed automatically when the print is done.

Replacing the electronic controls in the CubeX is a $40 decision. The stand alone is more work / cost than doing the whole thing. That's why you don't see any web sites dedicated to explaining how to switch out just the heated bed controls.

I'd probably opt for the varying temperature then. I've heard of people putting RAMBo's in CubeX's, but those are ~$180 ( [ultimachine.com] ). Is there another board people are using that's $40?

A Ramps 1.4 + Mega 2560 is roughly $40. I'd bet it will do the job. Don't know if it will fit inside the box....

I've looked into the RAMBo possibility and it's becoming more feasible to me, it's kind of confusing with all the different configurations. I'd wire the two Y motors in parallel, which I'll check when I take the bottom panel off because I think that's how they're wired anyway.
I just have 3 more questions:
-I have a Duo so that means I have 2 extruders, if I switch to Ramps does that mean I can only use one or can the board accommodate 2 extruders and I just haven't seen one wired like that?
-If I went with Marlin on board, that would work with KISSlicer correct?
-And I would need a separate printer interface to use with KISSlicer like Pronterface, correct?

Sorry for all the questions, but you've been a huge help. Thanks, uncle_bob

What gauge of wire is best for Mk2 Heat Bed using Arduino Mega 2560 and RAMPS 1.4?

If you go by the "official" wire gauge current charts, you could get by with 20ga for chassis wiring for a 10a draw, but that is really pushing it. I personally wouldn't use anything smaller than 14ga for the typical load. This presumes 12v 10 amp draw. If your board's resistance is lower than 1.2 ohms, then you might want to go bigger gauge (smaller number).