ST3Di Modelsmart 280 - Duet Maestro repair/upgrade

Blacksheep99 · 6 Jan 2021, 13:44

@jay_s_uk said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

Either way to be honest.
My preference is to use the correct voltage fans but other people are happy with buck converters

I think I side with you. I'll order some fans

Veti · 6 Jan 2021, 13:47

ok thats inline with a 100k ntc thermistor.

but which one is not as easy to determine.

can you put the thermistor at 100C using a known good temperature measuring tool?

i.e here is a beta 3950 resistance table.
https://www.keenovo.com/NTC-Thermistor-R-T-Table.pdf

Blacksheep99 · 6 Jan 2021, 13:55

@Veti said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

ok thats inline with a 100k ntc thermistor.

but which one is not as easy to determine.

can you put the thermistor at 100C using a known good temperature measuring tool?

i.e here is a beta 3950 resistance table.
https://www.keenovo.com/NTC-Thermistor-R-T-Table.pdf

I'm not sure how I'd go about that especially with what I have available at the moment. Am I daft thinking i could try suspend it in some boiling water and measure it then?

Veti · 6 Jan 2021, 13:58

can you post a picture of the thermistor in the hotend?

Blacksheep99 · 6 Jan 2021, 13:59

@Veti said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

can you post a picture of the thermistor in the hotend?

I'll try. I've a work call now but will do it after.

thanks for your help.

A Former User · 6 Jan 2021, 14:41

How was the original board configured - maybe you can borrow some info from there?

Blacksheep99 · 6 Jan 2021, 14:42

Best I can manage at the moment. I'll have to take the shroud off etc.

Blacksheep99 · 6 Jan 2021, 14:46

@bearer said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

How was the original board configured - maybe you can borrow some info from there?

Pics.

Blacksheep99 · 6 Jan 2021, 14:49

This other board was below the touch screen.

A Former User · 1 Jun 2021, 14:53

Ouch / RIP. No immediately obvious easy way to get anything from that, the main cpu on the motion controller had seen better days indeed.

(there is what looks like a 8 pin soic flash chip, but might not be worth while extracting it if settings are in the other cpu's flash / eeprom)

Blacksheep99 · 6 Jan 2021, 14:52

@bearer It didn't smell too great when that happened

Blacksheep99 · 6 Jan 2021, 14:53

@Veti said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

ok thats inline with a 100k ntc thermistor.

but which one is not as easy to determine.

can you put the thermistor at 100C using a known good temperature measuring tool?

i.e here is a beta 3950 resistance table.
https://www.keenovo.com/NTC-Thermistor-R-T-Table.pdf

I have an infrared thermometer gun (for the pizza oven). How about in the oven and use that to read the surface temp of it?

A Former User · 6 Jan 2021, 14:57

if the oven temp is stable then it should work if left long enough for temperature to equalize on the board and oven; i prefer to use water with crushed ice and boiling water for a 2 point calibration as its more stable and water conducts the temperature better than air (but water does have its own challenges)

A Former User · 6 Jan 2021, 14:59

Also as you'll tweak the print profile it doesn't matter if you print at 210 or 215 as long as you get consistent results - i.e. precision is more important than accuracy unless running a print farm.

Blacksheep99 · 6 Jan 2021, 15:10

@bearer said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

Also as you'll tweak the print profile it doesn't matter if you print at 210 or 215 as long as you get consistent results - i.e. precision is more important than accuracy unless running a print farm.

That's a good point. It will be run as a lone printer.

Veti · 1 Jun 2021, 15:37

@Blacksheep99 said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

I have an infrared thermometer gun (for the pizza oven). How about in the oven and use that to read the surface temp of it?

that will work for the bed, but for the hotend there will be a temperature difference between the nozzle and the surface.

maybe its possible to replace the thermistor with a known one. thats why i asked for a picture.

@bearer said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

Also as you'll tweak the print profile it doesn't matter if you print at 210 or 215 as long as you get consistent results - i.e. precision is more important than accuracy unless running a print farm.

yes the problem is that the difference between a semitec 104gt2 and a b3950 setting is more than 20C at 200C

Blacksheep99 · 6 Jan 2021, 15:47

@Veti said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

@Blacksheep99 said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:

I have an infrared thermometer gun (for the pizza oven). How about in the oven and use that to read the surface temp of it?

that will work for the bed, but for the hotend there will be a temperature difference between the nozzle and the surface.

maybe its possible to replace the thermistor with a known one. thats why i asked for a picture.

@bearer said in ST3Di Modelsmart 280 - Duet Maestro repair/upgrade:
 Also as you'll tweak the print profile it doesn't matter if you print at 210 or 215 as long as you get consistent results - i.e. precision is more important than accuracy unless running a print farm.
yes the problem is that the difference between a semitec 104gt2 and a b3950 setting is more than 20C at 200C

I'll take the hotend out tonight and see if it can be ID'd.

Blacksheep99 · 6 Jan 2021, 17:50

Not sure these help?

Blacksheep99 · 6 Jan 2021, 17:52

The endstop/probe. 12v, is that an issue?

JamesM · 1 Jun 2021, 18:32

It could just be a simple microswitch that is rated to handle 12 volts in which case it won't matter if you only use 3.3 volts. You'll need to just use an ohm meter on the wire ends to see if it that style switch. If it only has two wires I would suspect it's just a normal microswitch.