extruder exerciser issues

Hey All,

I am attempting to activate the heater in the extruder exerciser in the reprap software and it does not seem to be working. The corresponding led on the PWM board dimly lights but the temp does not change nor does the heater get warm let alone hot. My PWM board works fine when I run just the test code for it on arduino. Also, the heater does get hot when I apply 12vdc directly to it as in the curing process for the cement. In the extruder exerciser extruder motor works in both forward and reverse and I can regulate the speed. Likewise the cooling fan works when I check the box to activate it. I am getting a temp reading of -28 C which seems odd. Could this be the issue? If so any ideas on how I correct it? I am using I believe a EPCOS 100K thermistor. I tested it using the arduino test code inserting the table for that particular thermistor on the reprap thermistor page. When running this code I got temp readings that seem pretty close to what is in my studio and when I run a heat gun in the direction of the heater the numbers jump up as I would expect. So I assume that this is correct. Does this table also need to be inserted into the arduino host software? Single_Arduino_Snap.pde I looked for something resembling the table in the code but could not find it. Being new to arduino I do not feel comfortable meddling too much. Has anyone else had a similar problem? Any ideas?

cheerio!

Hi

You need to change the table in the library file as per these instructions

1. Lookup the values for your thermistor.
2. In the ThermoplastExtruder subdirectory of your Arduino library, create a symbolic link to the appropriate file (which will be something like Thermistor_r0_100000_t0_25_r1_0_r2_4700_beta_3960.h) called ThermistorTable.h.
3. Delete ThermoplastExtruder.o (if it exists) This is the old object file and will force the library to recompile.
4. Run the host software for driving RepRap on your computer. Select Files->Preferences->Extruder_0
5. Change Extruder0_Beta(K) to 550.0, Extruder0_Capacitor(F) to 0.000003, and Extruder0_Rz(ohms) to 4837 regardless of what your actual thermistor values are. Click on OK.

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Regards

Ian

Hey Thanks Ian.... I am now extruding

I have the same problem. I am running on windows with the RRf 100K thermistor.

I do not know what
"create a symbolic link to the appropriate file (which will be something like Thermistor_r0_100000_t0_25_r1_0_r2_4700_beta_3960.h) called ThermistorTable.h." means.

Specifically the create a symbolic link part.

Sorry for my ignorance!

Andy

The term "symbolic link" is Unix/Linux speak for what Windows users would call a "shortcut" and Max OS X user would call an "alias". Another way to do it is to make a copy of the desired version of the file and name it with the desired name.


andy hall Wrote:
-------------------------------------------------------
> I do not know what
> "create a symbolic link to the appropriate file
> (which will be something like
> Thermistor_r0_100000_t0_25_r1_0_r2_4700_beta_3960.
> h) called ThermistorTable.h." means.

Quote

The term "symbolic link" is Unix/Linux speak for what Windows users would call a "shortcut"

Tragically, windows shortcuts are only a pale imitation of symbolic links. You'll have to do some copying and pasting instead, if a symbolic link is definitely what is needed here.

Hi Andy

Open ThermoplastExtruder.cpp with an editor

Check the name of the thermistor table include file.

In the latest firmware I think it is #include "TemperatureSensor.h" but in the version you have it may be "ThermistorTable.h"

Close the file.

Identify the thermistor file you need for your thermistor e.g. Thermistor_r0_100000_t0_25_r1_0_r2_4700_beta_3960.h

Open in an editor

Save as ThermistorTable.h or TemperatureSensor.h whichever is being used in your cpp file.

Close the editor

Delete ThermoplastExtruder.o (if it exists) This is the old object file and will force the library to recompile.


Run arduino software and recompile. Your thermistor data will now be used via the included header file.

I hope this makes sense.

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Regards

Ian

Many thanks Ian , That is much clearer and it worked!

Sorry for the delay in replying term started and I had to plan lessons and teach!
Andy