Figuring out how to get the thermistor values into sprinter for my qd-db extruder.

I’m did a little bit of a happy dance the other day.   I managed to get my Qd-bd extruder to poop for the first time.
I got my little wiring breakout board done, and I cut a piece of glass to used double sided tape to get it to stick to the table.   Since my rig mounts to a flat marble plate, I’m going to attempt to not use the springs to preload the table… We’ll see how that works.

Ok… In the initial pooping experiments, I used the default values in sprinter for a 100K thermistor and it seems like I couldn’t get anything to work till I was at 220C.  Soooo… those values must be in the code somewhere.

In sprinter there is a file called thermistortables.h

I made the following hacks and pasted in the values from

Ok.. I confused myself earlier but I think I understand things now.

So basically the Arduino can measure 5V and bust it up into 0 to 1023. Digital.
So what I think we’re looking at in the thermistor tables here:  is the digital value from 0 to 1023 on the left side and the corresponding temperature on the the other.
Here’s something I need to look at.
Ok.. So I have the table resistance from Qb-db now I need to figure out what the resistance is in the Ramp 1.4 Arduino.
According to this is 4.7Kohm

I played around with my tables… And started playing around with a test cube.. But no joy…  It seems like like I’m not getting enough grip with the wheel I hobbed.   I used smallest tap that would fit into an R8 collet.   I’m thinking that  was too large a radius.   I tried the qu-db gear as well and no joy as well.
It seemed like I could get plastic to extrude when I press down on the filament, but my wheel just isn’t gripping enough.
I googled a bit and found something of interest…

Sooo… I think I need to put this aside for a while.. I think I need to hob another gear with a smaller tap..   I have a lassy tapper, that could hold the tap and then hold that with an R-8…  Holding it with a drill chuck is not and option since the side load would push it out of the holder.

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