I am trying to tune my process to print using PCTG, which oozes like crazy. I am trying to optimize both my Retraction and Extra Restart Distance settings.
I tried to run a print yesterday, and it barely got part way through the first bit of the initial skirt when it stopped extruding. Closer examination showed that it had retracted the filament all the way out of the extruder.
I checked my settings for a typo, but didn't notice anything initially. I took a look at the Gcode, and the retraction commands were there, but there were NO corresponding de-retractions. I was trying to use a Retraction of 2.2 mm, with an Extra Restart Distance of -0.11 mm, so there should have been extrusion commands calling for E2.09 a few lines after every retraction command. They were no where to be found.
I went back and took a closer look, and I had a typo in the Extra Restart Distance. Instead of the -0.11 mm I wanted, I had typed -11.0.
The slicer didn't complain about trying to use an ERD that would result in a negative total retraction, it just stripped those extrusion commands completely out of the resulting Gcode. As a result, I had a series of retractions, which quickly removed the filament from my extruder.
I don't actually recall EVER seeing an error message from S3D saying "illegal parameter value", "value out of range", etc. Maybe they are in there for some conditions, but if so, you missed one.
Thanks!
Re: Bug Report: Lack of Range Checking on Extra Restart Distance
I know we try to add checks for invalid settings when we can, but it's definitely harder for something like retractions. Some machines will have a 0.5mm retraction while others with something like a bowden tube might have 15mm retractions. That's a huge difference! Some people with really oozy extruders also prefer to use a big negative extra retract distance, so retracting 15mm but then priming only 10mm with a -5mm extra restart could be normal for some cases.
It sounds like your settings were crazy enough maybe it would have warranted a warning, but just wanted to explain that sometimes it's hard to know what's normal vs a mistake when some of these settings have huge normal ranges.
It sounds like your settings were crazy enough maybe it would have warranted a warning, but just wanted to explain that sometimes it's hard to know what's normal vs a mistake when some of these settings have huge normal ranges.
Re: Bug Report: Lack of Range Checking on Extra Restart Distance
In my case, the Extra Restart Distance was larger magnitude than the Retraction, which I think should throw an error in any case.
If you want to accommodate weird values, that's fine, but in my case, it removed the de-retraction command entirely from the Gcode. For my parameters, Retraction of 2.2 mm, with an Extra Restart Distance of -11 mm, it should have commanded E-8.8, which I would have seen in the Gcode & Immediately gone looking more closely for a reason.
If you want to accommodate weird values, that's fine, but in my case, it removed the de-retraction command entirely from the Gcode. For my parameters, Retraction of 2.2 mm, with an Extra Restart Distance of -11 mm, it should have commanded E-8.8, which I would have seen in the Gcode & Immediately gone looking more closely for a reason.
