Upsilon . . . an experiment

[longshot]

So I'll start off by saying I love my Rostock Max. But I have to add that my printer has not been running for well over 6months with the modifications. My patience nearly ran out till just now.

As the title of this post suggests Upsilon is a method where I there are 2 inputs of filament to a single nozzle output. My original and futile attempts of getting a dual nozzle setup featured two E3D V5 nozzles along with 2 cold end extruders of my design. Everything was wired up with no problems. The issue came with alignment. The daunting tasks of making sure the heads of the nozzles were aligned, account for printer radius, adjusting towers and endstops, etc. And endless struggle of taking apart the hot end and adjusting, taking it apart and adjusting. I would come close only to get to the point where the other non extruding nozzle would knock my part off the table. Other times the nozzle dug in so close to the bed that it would mash filament into the print area. I've replaced the build plate with PEI and boro glass to improve adhesion for ABS and done a number of other mods to help. Bottom line, I've spent way too much money and time on this thing and really just need it to work.

Before folks start pointing me to places of why the Upsilon doesn't work I'll start off by saying here is where I found the idea and hopefully what saves the printer and my sanity:

http://forum.seemecnc.com/viewtopic.php?f=77&t=6081" onclick="window.open(this.href);return false; and here http://forum.seemecnc.com/viewtopic.php ... lon#p52100" onclick="window.open(this.href);return false;

The biggest pitfall is the strings being caught in the heater block during retraction and causing a jam. I'm running ABS and HIPS only. There is no intention at this moment to be running anything different. Both seem to fair well at the same 230C temp so a temp difference shouldn't be an issue. I believe if i adjust the retraction speed and amount I might be able to control the amount of strings when retracting. If this works, and I'm crossing my fingers, then that means i only need to cal in a single nozzle. A task that is much more possible than with 2 extruders side by side.

There are a few obstacles . .

So what I need help is the pin.h and configuration.h. The trick is to get the 2nd extruder looking at the temp that is on the 1st nozzle. Can someone help me with this? I'm afraid I can easily burn something if I'm not careful.

Thanks in advance

[AndyB]

So I just looked at the code in github for 0.91 SeeMeCNC version, and I don't see why you couldn't define EXT1_(HEATER|TEMPSENSOR|COOLER)_PIN values to the same values as EXT0_<*>_PIN

In Configuration.h line 303
#define EXT1_TEMPSENSOR_PIN TEMP_2_PIN

Set it to TEMP_0_PIN and that should work. You need to set NUM_EXTRUDERS = 2 for any of this to work. From a quick glance of the code (I program for a living) it looks like you will be setting the pins up twice, but this won't hurt a thing. The logic should work fine for the second extruder if you just configure the EXT1_ defines to look like the proper mix of EXT0_ defines (your extruder stepper pins are different).

Andy

[jdurand]

The only problem I could see is if the software tries to turn off EXT1 at the same time it's turning on EXT0. Not sure how it would sort that.

[AndyB]

Also, you will need to set EXT1_TEMPSENSOR_TYPE 97 (it is currently 3). You really should search for HEATER TEMPSENSOR COOLER in those files.

As jdurand points out, that would depend on the order that the logic was written. I would assume that a smart programmer would turn off something before turning on something -- having multiple devices on at the same time would draw a lot of current. So, if they turn it off before turning it on, it wouldn't matter. The toggle should happen in microseconds which I doubt would be noticeable in the print. I haven't looked for this code, but you could find EXT0_ patterns using github's search.

It looks like the extruders are stored in an indexed array called extruder[]. Look at commands.cpp to see how it handles that.

I assume there is a GCODE to switch extruders, Once you find it, you can look into commands.cpp to see the logic. I couldn't find it, but the code is well structured and I'm going to bet that you won't have an issue.

[AndyB]

Look at ext1_select_cmd and ext1_deselect_cmd in extruder.cpp

[Nylocke]

If you're going to do this, do it right. .91 and .92 branches of Repetier are available from the website. They have a config tool that makes it easy to set up. If you need help I have set up several copies of the .91 and .92 releases for my machine. Both of these versions support mixing extruders from what I remember. .92 definitely does. I'd advise using whats already there

[mkx]

Stringing is a huge issue, so if you figure out how to get around that, that would be great!

[JFettig]

Anyone having any luck with the upsilon? I'm tempted to give it a shot, I want to run 2 1lb spools to print a 1.25lb part using one spool for infill and another spool for the outer perimeters.