Hi all
My printer is H-bot with Bowden extruder. Have problem on Smoothie. Looks like it micro drags before retract so I have blobs right on retraction points :(
Migrated from arduino/ramps on Marlin and doesn't have that problem on it. It seems like Marlin retract little bit earlier or doesn't stop ont retract points. Can't explain it correctly.
Tried different firmwares, change accelerations in config, retraction speed in slicer and always the same blobs on retraction points. There are no other problems.
Any advice?
I just thought I'd chime in and give a +1.. I've been having a hell of a time trying to figure out this exact issue since switching to Slic3r & Octoprint from pure Simplify3D.
It's like it experiences a pause prior to retraction -OR- perimeter change.
whats your retraction length set to? may just need to turn it up as you need more retraction with Bowden and all software will behave a little differently.
It's not retract length or speed problem. Tried 3-15mm and 40-200 mm/s, all the same result. Write again - same slice settings (or G-code) on Marlin don't give blobs.
Have you tried changing the extruder's acceleration ?
Your problem isn't a common one, I'm not sure how to address it.
https://github.com/Smoothieware/Smoothieware/commits/edge/FirmwareBin/firmware.bin
Though if you find something it's likely it'll just be random/un-reproducible.
I thought I'd tag onto this thread. I'm having similar issues with blobbing, buy mine are at the start of the layer. I'm using an Ultibots delta printer with an E3D v6 hotend and PG35L geared stepper filament drive. Also, I'm using Slic3r 1.3x to do all the retractions (for the wipe feature), and Smoothie as the g-code flavor.
When I use firmware retraction I don't get blobs at all, which suggests this is a Slic3r/Smoothie combination issue.
I can control the start blobs by using setting a negative extra restart distance, but I suspect there is a more fundamental fix somewhere.
I have images that illustrate the issue quite well, but I can't post links with my current "karma".