Holes in curved sheet metal

[daniel.ea.kron]

Hi. I'm trying to make holes on a curved sheet metal surface. The holes need to be normal to the face of the sheet metal of course. The intention is to make threads in the holes after the sheet metal has been cut out for production and been bent. As one knows, it is not possible to use the unfold and fold command for curved surfaces that do not have a "normal" face. Therefor I have to use the "flat pattern" command before makin the drawing.

My design consist of 2 curved sheet metals that will be bolted together with countersunk screws. Ideally I think the best result will be achieved if it was possible to make an assembly of the 2 components and then drill into both sheet metals using the hole command, and thereafter make the threads in one of the sheet metals. Is that possible? Note: I have the hole pattern in a sketch (maybe I can project the sketch onto the sheet metal?) 🤷‍:male_sign:

I attach an assembly of two sheet metals that I want to bolt together.

NOTE: The holes (pattern) are found in respective sketch for each part (sketch2). It is the same sketch in both parts. Maybe I can add a sketch in the assembly which I can use to cut both screens? 🤷‍:male_sign: 

Sincerely
Daniel  

[davebYYPCU]

Hole Tool, and curved faces do not compute.

If your sketch point is located on a Tangent Plane, you select the plane for the hole starting position, because it is a flat plane.  

You can Offset that plane for another sketch / sketch point, but I am not sure of the last question.

Might help....

[hamid.sh.]

If your goal is just render and sheet metal's curve profile is circular (my sketch 1) you can try this: make one cylindrical hole normal to face, unfold, pattern Faces of (now oval) hole, refold, apply thread (all of the oval holes refold back to cylindrical, so can be selected for thread):

It's just that when you have a hole on a non-flat surface modeled thread generates this (not related to unfold/refold; unsuppress my first thread to see it has same effect. If thread tool let extending it could be solved):