Converting old TAZ 4 extruder to flexystruder

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dutchhome
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Re: Converting old TAZ 4 extruder to flexystruder

Post by dutchhome » Wed Mar 25, 2015 11:46 am

All I can tell you is the heating resistor in the hexagon hot end has both leads on one side where the heating resistor on the budaschnozzle has one lead on each side. I'm not sure if it would be sturdy enough to put the new resistor in old hot end.

I wish I knew what is so different. When I find myself curious of the differences it is when I don't have the time to dig into the code/configuration. I think all we need to do is compare the configuration.h files in the two Marlin packages. I know the PID settings will be different, but I don't know what else.
Lulzbot TAZ 4.1
Upgraded to Hexagon Extruder
Converted old extruder to Flexystruder 1.1

Wolfie
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Re: Converting old TAZ 4 extruder to flexystruder

Post by Wolfie » Wed Mar 25, 2015 12:58 pm

According to the two arduino sketches...

Dualie and flexi both use type 7 thermisters. The Hex uses a type 5.
// 5 is 100K thermistor - ATC Semitec 104GT-2 (Used in ParCan & J-Head) (4.7k pullup)
// 7 is 100k Honeywell thermistor 135-104LAG-J01 (4.7k pullup)

I also get different Kp, Ki and Kd:
// Buda 2.0 on 24V
#define DEFAULT_Kp 14.09
#define DEFAULT_Ki 0.75
#define DEFAULT_Kd 66.00

// AO-Hexagon (24V)
#define DEFAULT_Kp 34.26
#define DEFAULT_Ki 2.83
#define DEFAULT_Kd 103.84
LulzBot Taz 5

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dutchhome
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Re: Converting old TAZ 4 extruder to flexystruder

Post by dutchhome » Wed Mar 25, 2015 1:09 pm

Nice! I was sure there had to be something like this. Completely explains why my resistor fried when I used the wrong firmware. Would be nice to add this to the menu.. To be able to choose between multiple profiles (number and types of extruders, PID configs, etc). They like to use preprocessor directives everywhere though, so it really isn't designed to allow switching configurations like this :(

That could be another weekend project.. I wonder if the space savings are required to fit everything in the Arduino board. Or maybe its a question of speed since it is a realtime system. Either way it is worth spending some time trying to understand better.
Lulzbot TAZ 4.1
Upgraded to Hexagon Extruder
Converted old extruder to Flexystruder 1.1

KosmoPi
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Re: Converting old TAZ 4 extruder to flexystruder

Post by KosmoPi » Wed Mar 25, 2015 5:11 pm

FYI, the hexagon hot end uses a heater cartridge, not a heater resistor. In my opinion this is a major improvement (it should be a little more reliable). This might be why the firmware is so different.

oppfinnarn
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Re: Converting old TAZ 4 extruder to flexystruder

Post by oppfinnarn » Thu Mar 26, 2015 3:31 am

Ok. Good info!

Then I guess it's just going with three different firmwares (hexa, buda and dual) until all the budas have become hexes.. :) I wonder if we could get a package deal on three Hexagons? :)

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do-it-for-science-
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Re: Converting old TAZ 4 extruder to flexystruder

Post by do-it-for-science- » Mon Apr 06, 2015 3:24 pm

would it be possible to create a firmware that would handle a dually setup with a budaschnozzle 2.0 and a hexagon? I already have the buda, but want to get a dual printing setup going without missing out on the high temp stuff or having to buy two hotends.
open source, open heart,

Jeff Hunt,
Renewable Energy Engineering student OIT

Wolfie
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Re: Converting old TAZ 4 extruder to flexystruder

Post by Wolfie » Tue Apr 07, 2015 1:19 pm

do-it-for-science- wrote:would it be possible to create a firmware that would handle a dually setup with a budaschnozzle 2.0 and a hexagon? I already have the buda, but want to get a dual printing setup going without missing out on the high temp stuff or having to buy two hotends.
I had hoped so. But, without rewriting a lot of code, no. The code references defined values rather than variables. And there is no provision for denoting values for one extruder from another as far as resistor/element type. From outward appearances, it seems that the code was written with only a single extruder in mind. Then later patched for multiple extruders.

Like you, I wanted to combine them. Without nearly a complete rewrite of the marlin software, its simply not going to happen.

What I would like it to have been done like... Store the heater types, the PID values, etc in EPROM. Then allow them to be defined per extruder and stored as a "Tool Head" setting. Lets say you drop in a hex single extruder. You set up Tool Head 1 with the proper heater type and PID values. Store that. Then say you get a flexi-dualie. So you set up Tool Head 2 with the proper heater types with PIDs for dual buddas. Then when you put your hex single back on, you recall tool head 1 and go. Thats the way it should work. Unfortunately we are well away from that.

I do not consider myself a programming expert. But I have been doing it since the late 70's so I got a pretty good experience level to base things on. Some experience on Arduino's. Some on Pi's. And a hell of a lot in desktop programming going back to 8080's, 6502's and Z80's as low level as hand coding machine code (no compiler). Now, whether I can re-code Marlin to do these things I want (and apparently many others), I don't know. I have to look at memory available to store the values as well as code memory to run them.
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kcchen_00
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Re: Converting old TAZ 4 extruder to flexystruder

Post by kcchen_00 » Tue Apr 07, 2015 2:43 pm

I thought the only difference between the codes were the thermister types... Wonder if would it be possible to replace the buda thermister with a spare from the hex? Then you should be able to keep the hex firmware... just make sure you don't overheat the buda.

But as usual... I could be making it sound too simple. :)

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dutchhome
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Re: Converting old TAZ 4 extruder to flexystruder

Post by dutchhome » Wed Apr 08, 2015 9:03 pm

I believe the difference is the heater type. When I powered up my flexystruder after the conversion, the thermistor seemed to be registering correctly. The resistor however was glowing red hot and eventually failed.
Lulzbot TAZ 4.1
Upgraded to Hexagon Extruder
Converted old extruder to Flexystruder 1.1

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do-it-for-science-
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Re: Converting old TAZ 4 extruder to flexystruder

Post by do-it-for-science- » Thu Apr 09, 2015 7:30 pm

that sounds like an amazing solution, I really want to try that now. I would love to hear if any of the staff have an opinion on this.
open source, open heart,

Jeff Hunt,
Renewable Energy Engineering student OIT

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