Large Blob when switching Extruders

[Arcadenut]

This is what happens when I am using dual extruders. What is really strange is it only happens on a certain layer (not sure which layer it is) and happens in the same spot every time. Different models get different spots. It happens with all my multi-color prints.

It only does it for the color that it just finished, not the one it's about to start. It's like it should be retracting at that point, but it's actually extruding. It's not like a little oozing, this is a significant amount.

[JoeJ]

Sounds like you may have a weird tool change script or tool change retraction settings. Why don't you post your factory file? (file --> save factory file)

[billyd]

I have this issue. It only happens on the first tool change. It's because I have the tool change code set to retract 12mm on the dormant extruder. Problem is, when it first switches to tool 1, the software assumes that tool is retracted 12mm, but it isn't because both extruders are primed at the start of the print.

So for only the first tool change in a print, the software needs to not unretract T1.

If someone can tell me how to fix this in the gcode I would appreciate it, until the folks at S3D can address this issue.

[JoeJ]

Does this only happen on the very first layer? or does it continue to happen for the rest of the print?

Can you post a factory file so I can see what settings you are using?

[billyd]

Does this only happen on the very first layer? or does it continue to happen for the rest of the print?

Can you post a factory file so I can see what settings you are using?

Just the very first tool change. Again this is because both nozzles start out primed. But because I have a tool change retraction set to 12mm, when the first tool change occurs, (from T0 to T1) T1 has not retracted and is ready to print, but the software extrudes 12mm anyway, as though T1 had been retracted. Once the initial tool change occurs, it never happens again (the blob) because now the tool has actually been retracted and needs to extrude to prime the nozzle.

[Arcadenut]

I don't think our issues are 100% the same. I'm going to have to video it and then watch when it happens. Mine seems to be on the second tool change (Layer 2) and it seems to be the color it's changing FROM and not the one it's changing too. I will video tape it and review the video after it's done.

[Arcadenut]

Ok, this gets a bit strange...

I took video of it, and it's the left extruder that is putting out too much. The weird thing is, is that White is loaded in the left extruder and it looks like a blob of BLUE.

The video can be seen here:
https://www.youtube.com/watch?v=z48xFEo ... e=youtu.be

It appears to be happening on Layer 4, which means it's done several tool changes up to this point. If this was on Layer 1, I would agree that it would be a priming issue, however, I don't think that's the case here. I have attached the G Code file if anyone wants to take a look at it. The problem area is around line 5285 (at least that's what was displayed by Simplify3D at the time the blob was extruded).