Support break

[Skyler]

Hi all, this is the second time I have the support break at the base, the print sticks great as do the brims, both time its happened at the same point, any advice would be much appreciated, Andy

[Geit]

You probably have to much retract. The area on the stem is quite small and after retract and moving to there, the filament does not (not always) push out the nozzle instantly.

So it takes a few mm to push out plastic, but on your little stem, there is not much surface to dump filament and when it comes out the layer is done or nearly done, so the next layer has nothing to build on and will be weaker, too. The problem piles up until it reaches a layer where previous layers failed and dumps in the air.

The reason for that happening at the same height is, because each print is the same and your printer is very consistent in reproducing the same result, which is a good thing in general.

Solution is less retract. You could add a bigger support area, but this is more a try and error solution.

You could also check the e-stops. If you have under extrusion in general, this probably gets visible in small areas after retract, too.

[Skyler]

Thank you for the advice I'll reduce it later, I'll let you know how it goes, thank you Andy

[Skyler]

Hi, I reduced the retract from six and half mm, to 3 mm, and it broke again, same time, the base off the support look fine, good cotact with the brim, thinking off trying tree supports, a good idea what do you reckon, thanks Andy

[Alan]

I mostly use Tree Supports. Highly recommend you give them a go. Probably will use more plastic and take more time, but worth it in my experience due to fewer failed prints.

Cheers

[Skyler]

Thanks, I'm on cura right now checking them out, Andy