nozzle approach on the otherside from a overhang

[spirit18 0]

Hi all,

 

i tried the support tree function for the first time and its amazing but! i keep having the issue that the part that overhangs curls up a bit. and the nozzle keeps baging into that part. which makes nasty crackling sound during printing. but it kan also detach a tree arm.

 

so my question is, is there a option that the nozzle only approaches the tree on the opposite side from the overhang.

 

 

[GregValiant 1,491]

There is no option to change the direction that the nozzle approaches the overhang.

If you enable "Z-Hop on retraction" then if there is a retraction prior to the travel move the nozzle will move up to clear it.  The height of the Z-hop is adjustable.

If you enable "Avoid Printed Parts When Traveling" the nozzle should go around the overhang.  The "avoid" distance is adjustable.

You might be able to to adjust the Combing Setting but it's usually one (or both) of those other two that works best.

[spirit18 0]

Hi thanks for the reply both options did not do the trick. but i found out that is you enable a feature it can show allot more options. (i allways used a other slicer before)

 

but i changed the support overhang angle to 30 degrees so the support would hold on to it  better and it worked perfect. it also did not curl up anymore.

[GregValiant 1,491]

I printed this with PETG which has a worse curling problem than PLA.  When you have a large horizontal hole like this one...

 

When the top of the hole closes it's going to curl.  My fix was to create a post processor that kills the Z-hop for particular layers.  In the case of the model above - I left the Z hops active just when the those top layers were going down and turning into feather edges.  With the Z-hop at 0.6mm there were no collisions.

 

I'm not a fan (bad pun intended) of some of the giant layer cooling systems I've seen but for a case like the one above a good efficient fan system is a must.  I ran the fan full blast for just those layers and that helped as well.