Hi, thanks for the reply.

To be clear - heating element is the only item that I connected to 18V.

The motor and all the fans are still on 12V.

I have one 18V power supply and a step-down unit from 18V to 12V.

You are aware that the motor controller is basically a buck converter right?  While you may need to convert the fan voltage, the motor control is a constant-voltage/constant-amperage PWM buck converter.

https://www.okystar.com/product-item/co … oky3497-7/

But yes, it is a lot of work. I parked this activity for a bit, but I plan to resume at some point. I started to work on an alternative approach - pellet extruder, so I could bypass making filament in a first place.

Murph, I'm not sure about the options in the UK. I was initially thinking to buy one tonne (1000kg) of PET plastic from Alibaba.com, but then I was able to get a sample of 50Kg from a PET factory in Lithuania - https://neogroup.eu/.
If I can make PET work for me, I would have to buy 1000Kg or more, but I'm not at this point yet.

I will also be experimenting with PET soon. It would seem you have found a well priced supplier of PET pellets.
Would you mind sharing your contact?

5.) Insert thermocouple into hole on hex flat of nozzle.

But given the picture that was posted by tomas0413, it doesn't look a if it's inserted into any hole. Is it just basically touching the head?

in my case it's this:

1) to be able to recycle plastic and use recycled plastic in 3D printing (not only PLA or ABS)
2) to reduce the cost of large 3D printed objects (let's say around 10kg in size)
3) The cost of PET granules per 1.3 EUR (per kg) (1.46 USD)
4) PET from www.re-filament.com (made from recycled plastic bottles) has been already successfully tested and works:
https://www.instagram.com/p/BimHp3DAu9H/
5) just general curiosity of learning something than just consuming

Keep in mind the stuff that we print with is not PET, but PETG and PETG+. So not sure if PET is even viable for 3D printing.

1. I'm able to get better results from PID on temperature stability, but it's not at the level which I'd be happy. Ideally, I'd like to achieve +/- 0.1C and in the worst case scenario + / - 0.5C. I ordered a different PID from Inkbird so that I can compare it to the Sestos.
2. I used Kapton tape to secure the thermosensor, but I didn't cover the entire nozzle. I plan to use heat insulation cotton to cover the nozzle and also use a bit more Kapton tape to secure the insulation.
3. I discovered the interesting results from 3DEVO that seem to be more or less in line with what I learned so far:
https://3devo.com/wp-content/uploads/20 … ycling.pdf

I'm trying to autotune without fans, to see if I can reach +/- 0.1C or something close to this.

I'm using these parameters at the moment:
M50 : 1500
P: 9998
t: 0
Ctl : 90
df: 0.1
oPH : 30 (I tied multiple values, 7 - the temperature only reaches 54C, 70 - the temperature overshoots by 20C or so)

Maybe someone who is able to get the stable temperature could check what values they use for: M50, P, t, Ctl, df and oPH?

1. I replaced the temperature sensor.
2. Put the Kapton tape to secure the temperature sensor.
3. Installed four fans with adjustable speed
4. I installed a 3mm stainless steel nozzle. (used to be 1.75mm stainless steel nozzle).

This time see that the best extrusion I get when I set the temperature to 230C (used to be 205C), so it's already entirely different.
I managed to extrude 1.75mm filament, which is excellent, but there will be a lot more work needed to get the width consistent.
I have a Filawinder ready but haven't tried it yet.

Also, the temperature is much more stable now, but still +/-5C. (After autotune).

I found this blog post, I'll if I need to get manual settings to get more constant temperature :
http://sestosd1s.blogspot.com/2015/04/s … aving.html

Or maybe the sensor wire had to be routed inside the insulation and insulation then could be lowered a bit?

Any suggests are welcome!

Thanks, everyone.

If you do that just make sure the wire isn't directly touching the heater band. I like to run it so that the screw that you tighten to hold the clamp onto the heater band prevents the wire from being able to touch the heater band.

-os3dp

Any suggests are welcome!

Thanks, everyone.