A little help with tree supports?

Tree supports are awesome, when they work

Yes, yes… I previously have talked about the current FDM printer generation’s ability to print with way less support than in the past. That doesn’t really change the need for support when talking about cantilevered sections (or other, valid support situations).

My previous issue with tree supports wasn’t really solved… it was just made moot by printing the model without support. Here I am a few models later, needing supports, still having the same issue.

Failure mode #1: the nozzle is crashing on tree supports. It’s pretty infrequent, but still catastrophic when it happens. Not only does it knock the tree support off of the build plate, but the filament that’s extruded to go on the support can foul other areas of the print. It’s not a brim issue. Speed contributes to the problem, but it still happens occasionally with speeds turned way down.

Failure Mode #2: there are times when the nozzle doesn’t knock the tree support off of the base, but the nozzle crash does cause a nozzle clog. By the time the nozzle has cleared the clog, it will have “missed” some portion of the layer AND dropped a glob of filament somewhere it shouldn’t.

Either failure mode is bad.

I’ve tried some of the tree support variants, including the ones that merge adjacent shells together for rigidity and strength. That hasn’t been a complete solve for me, either.

I the issue has to do with the first layer. Specifically, I think my Z-offset puts the first layer in a state of too much squish, creating a layer flatness issue that presents as both weakness and height problems. I think there’s an offset adjustment on the printer, and I’ll post again with my progress. If anyone has suggestions, short of rooting the printer, feel free to email admin@dad-the-engineer.com