Up 3D printer modification

 UP!3D is my first 3d printer, it works great out of box, but after all these years(about 10years!), it start to show problem.

The head unit cables are broken internally, the heater is not stable, temperature could drop when printing. 

So, find the pin outs and redo external wires is what I did:

Blue and red for heater, black and yellow for temp sensor.

Motor 4 wires

Later on, the heat bed is having the same issue, So, I did the same thing with heater and sensor(PTC100)

This time, I want to do more, the heat bed of this up 3D is not very efficient, it would take 40min to heat up to 90-100 degree. So I order some new voron 0.1 heat bed and aluminum plate.  I ordered 12V version, since I "believe" the original one is 12V, since the power supply for the whole system is 19V. But, in reality, it's a 24V one, and connected directly to 19V, controlled by a N channel at low side.

I also removed the NTC came with, since afinia system use PTC100

I powered it with power supply and takes about 6A at 12V

If I power it with 19V, it would be 9A, I'm sure some thing will be burned.

I was thinking about getting a DCDC to get 12V from 19V power supply, but 6A DCDC converter is quite big, and I'm not sure if the original 19V power supply is good enough. 

I end up with adding a 110V AC to 12V DC power supply to do the job.

Since the main board of my 3D up is using N channel most to do the PWM control on power negative side. I feed to 12V power to the heat pad, and connect both negative ground together.

But soon I found out that the original one N channel mosfet is not strong enough, it get hot at only 4A, with 5A it heated up to 90 degree.

 so I add another one bigger N channel mosfet, even with 6A it only heated at about 25/6 degree.

The mosfet is mounted on the metal housing, to reduce the heat.

This is how I fix the new panel on the old structure.

It back to work again!

The advantage is it's SW, nothing to worry, nothing to turn.