I'd love to be able to additionally select individual extruders not only for support in general but for
*) In case you intend to print more than one top interface layer (I like to choose 3 interface layers), I'm not sure if this option should affect all interface layers in general or just the topmost interface layer that directly connects to the object..
Agreed, an option for support interface layers is in my todo (I would extend it to all the interface layers, and not just to the contact one because they are somewhat mixed up when supporting sloping walls).
Raft is handled just like any other support material: it's got normal support layers and interface layers, according to the support material settings. So I think it should not have any separate extruder settings and it should just follow the ones chosen for support material.
Oh, you're right.
Raft should not have any bottom interface layer, though, so all raft from bottom up will be made by the "main support extruder" selection. But I assume it is/will be handled that way anyway?
Raft has normal support layers + interface layers, exactly like any other part of support material in the object. In addition, the bottom layer touching plate has a base flange (but that happens for normal support material anyway and not just for raft).
Ok, that makes sense to me.
Only the support doesn't generate bottom interface layers yet, right? (Assuming that not more than one bottom interface layer will be necessary when building support on top of the object's surface..)
Hm, I didn't think of it... Right... Do you propose to just do the specular thing as of the upper interface?
Not sure yet... Still thinking about possible (if any) advantages of multiple and optionally solid bottom interface layers.
Right now I'd suggest to just use the regular support pattern for the single lowermost support layer upon the objects surface but from secondary extruder/material like upper interface.
Solid or at least fine-meshed (and multiple) bottom interface layers may help with support material that doesn't want to stick too well to the objects material, but I cannot prove that yet. May be something to test with HIPS though, we've got some experimental 3mm HIPS filament on hand at the moment.
Well. If implementation would be easier for the specular tactic as you suggested, I'd prefer going that route. At least it won't hurt to have the same interface layer approach for bottom like for top..
New option for support material interface extruder. #1072
Okay, I implemented this one in the new-support2 branch.