Dual extrusion Taz 5 can't get tool offset to work

[billyd]

Hello I have a dual extruder on a Taz 5 and no matter what I set my tool 1 offset to, it never changes anything during the actual print. I've tried stock setting of 53 mm (I think it was 53, but it may have been slightly different) in Y and I've tried changing it during alignment calibration but the print out never changes. My second color (tool 1) is not aligned in Y properly regardless of what I set tool offet for tool 1 to. And it is always off by the same amount, so the tool1 offset is clearly being ignored.

I've attached a factory file of what I am trying to print. On my printer tool 1 needs to be adjusted about 2mm from where it is (in Y) to be aligned properly. But like I said nothing I change in tool offset (under the gcode tab) seems to have any effect on the actual printout.

Am I doing something wrong? In the old versions that didn't support dual extruders on the Taz I used to get it to work using global offset and two different processes. That worked fine but the preview would of course look strange.

[billyd]

Never mind I just found the problem I didn't check the check box to include tool offsets ( the Taz doesn't support it in firmware). Considering I am using the stock Taz dual extruder process S3D should have checked that box for me!

[CompoundCarl]

the Taz doesn't support it in firmware

That's not correct. I've used the TAZ dual extruder upgrade myself, and you can absolutely set the offset in the firmware! In fact, that is the recommended approach. You should really never set the offsets in the software. That's just a workaround for incorrect firmware settings.

Lulzbot even has links that recommend setting the offset in the firmware (https://devel.lulzbot.com/TAZ/accessori ... _Guide.odt). They just use standard marlin firmware, so it's really easy. Just edit one line in the Configuration.h file.

[billyd]

the Taz doesn't support it in firmware

That's not correct. I've used the TAZ dual extruder upgrade myself, and you can absolutely set the offset in the firmware! In fact, that is the recommended approach. You should really never set the offsets in the software. That's just a workaround for incorrect firmware settings.

Lulzbot even has links that recommend setting the offset in the firmware (https://devel.lulzbot.com/TAZ/accessori ... _Guide.odt). They just use standard marlin firmware, so it's really easy. Just edit one line in the Configuration.h file.

Thanks so much for this. I hadn't used the dual extruder in awhile and forgot I could change it in config.h

[billyd]

Ok I have a strange problem here. No matter what extruder offset I put into config.h my extruders are misaligned by the same about.

I've attached my config.h maybe you can tell me what I'm doing wrong.

My first numbers for T1 were x = -.1 and y= -48.5. I did a print, and the tool 1 solid was 3mm off in Y (in the positive direction). So then I changed the T1 offset in config.h to Y= -45.5 and reflashed. Then I printed the model again, and nothing changed. I tried reslicing too. Still 3mm out in the same direction. It seems like it's ignoring the setting in my firmware.

ps I am using Taz 4 firware because I can't find Taz 5 dual extruder firmware that has the source code for dual extruder. I could only find the hex file which is useless since I can't change the offset unless I have the source. RIght?

[CompoundCarl]

So there's 3 ways to set the toolhead offsets. I am going to list them in order of preference
1) firmware - this is always preferred. Toolhead offsets should be set by the manufacturers directly in the firmware so that people don't have to mess with it!
2) using gcode that is sent before every print (i.e. M218 command for Marlin printers) - this is a less preferred option. If you send a command like "M218 X0 Y-52 T1" before every single print, you can actually set the toolhead offsets for that print, overriding the settings in the firmware. This is less ideal, since it's easy to screw up if you accidentally print a different gcode file that doesn't include those special lines.
3) using the software - as mentioned above, this is the last resort and should really never be used.

So it looks like the S3D profiles for the TAZ dual actually have M218 commands in the starting script. So if you've done the right thing and set the toolhead offset in the firmware, then go ahead and remove the following lines from your starting script
M218 X0 Y0 T0
M218 X0 Y-52 T1

That way your firmware settings aren't being overwritten before each print

[billyd]

Thanks much appreciated! Will try it tonight.

[billyd]

That was it. Thanks so much.

[billyd]

Not to beat a dead horse on this topic because it's resolved, but....

I thought that S3D should know that it doesn't make much sense to have a place to put the tool offset in the Gcode tab of the software, but at the same time have a fixed tool offset being placed in the startup gcode in the stock profile of the the dual Taz as supplied by S3D. !!??

So for the stock profile of the dual Taz, you should probably remove the portion of the start up gcode that sets the tool offset. That was why my firmware and software settings were being essentially ignored. Anyway I found it confusing.

[JoeJ]

There is very good reason for doing that. If you read other posts on the topic, the toolhead offsets are used for many other things like path optimization and planning. Even if the toolhead offsets are handled by the firmware or by using M218, you still want the software to know what they are.