Paste extruder

Hi,

I'm building a paste extruder and it's almost finished.But the problem is that I had to keep the thermistor connected with the hot end since machine does't work with out a thermocouple connected with it and with out it reaching the temperature that I put in the slic3r. Since it is a paste extruder I don't want a temperature sensor, so is there any way to work it with out a thermocouple connected to the board. I mean it should print at any temperature
I tried changing

#define TEMP_SENSOR_0 0

but got the following error while uploading
"HEATER_0_MAXTEMP was not declared in this scope"

Edited 2 time(s). Last edit at 02/10/2016 08:16AM by athul.

... you can short the thermistor pins with a 10 kiloohm resistor or set the minimum temperature to 0:

#define HEATER_0_MINTEMP 0

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Viktor
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@VDX
I already set the minimum temperature to 0, but if I remove the thermocouple machine won't work(is that normal?)
What i'm doing now is that keep the thermocouple attached with the hot end , and put the temperature it shows in the slic3r (it won't be same always) and I don't want this way.
I'll try shorting with a resistor(wil it show constant temperature all the time?)

... yes, a resistor across the thermistor pins will show a constant 'temperature'.

Don't know, what's different with your setp - I have running 4 machines without thermistors with Due and RADDS - the first with the thermistor, then all without and '0-temp' defines ...

---

Viktor
--------
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I'm using printr board and in my case i'm sure that extruder won't work if I left the thermocouple disconnected . I even changed #defime TEMP_SENSOR_0 0 but arduino showed error while compiling.

If you give me your mail ID(PM) I can sent you the firmware i'm using(it's too large to attach here)

If I disconnect the thermocouple Repetier Host shows the temperature as -42 degree Celsius . Since the extruder can't reach that temperature it won't print.

And if I connect the thermocouple it'll show room temperature and print will only start If it reach the temperature mentioned in the slic3r(I can't use the exact room temperature in slic3r since it's not stable always)

... you have to set "#define TEMP_SENSOR_0 1", or it won't run!

Then you can set any temperature below min - for me "#define HEATER_0_MINTEMP 0" is enough, maybe you have to set it to "-50" or even below?

Shorting the pins with a proper resistor only sets the read temp to a 'valid' value above the predefined min-temp ...

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Quote

Then you can set any temperature below min - for me "#define HEATER_0_MINTEMP 0" is enough, maybe you have to set it to "-50" or even below?

In this case would the machine print if I put print temperature 0 degree Celsius in slic3r (or should I put -42)?

... I'm using Pronterface and Marlin4Due as firmware for my paste-dispensers - they print fine with min-temp set to 0 and with 'open' thermistor pins

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

I think for me in order to print with out thermocouple I need to put -42 or less in sllic3r but slic3r won't accept the value and I can't put 0 in sli3r since it needs thermocouple and hotend to bring temp from -42 to 0.
So I think the only solution is to use a resistor

Edited 1 time(s). Last edit at 02/13/2016 01:50AM by athul.