Cant get threads on curved surface

For some reason I cant get the EP fasteners thing to create threads on a curved surface. V-Block Assy(Modified for A2V).skp (3.3 MB) I want an M4 thread through the hole in the holder component 16mm up from the bottom and whenever I do and select thru hole, it doesn’t go all the way through on the inside. If I try to do it long enough to just select the model and threads and combine them, I then cannot remove the face because for some reason, it doesn’t intersect. Any ideas?

The most likely reason is scale, working too small. Try scaling up by 10 or 100 and having another go.

Edit: I see we have been through all this before with exactly the same thread title.

Because the EP Fasteners extension works on a single face. Your curved surface is not a single face. Make the screw longer, add a temporary face in front of the curved surface and put the screw on it. Then use Intersect faces and erase the unneeded stuff.

Dave you may well have said all that before in the other thread.

Very possibly. The threads made by this extension are not usable as they are for running a real screw into a hole. I thought the OP had given up on using it in favor of the other options I offered.

So I have heard of this scaling thing before. Do you scale up to say…100, do the work, and then scale down 100? How do you do the correct thread? I always try to do everything to scale so if I scale up 100, does that mean I have to create the M4 thread and include it when I scale?

And the Dave Method as mentioned.

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Working in metric units, I’d scale up by 1000 and set the units to meters. Enter the dimensions as if you were working in millimeters.

As I’ve told you at least once before, if you want decent usable threads, don’t use that extension. It doesn’t create usable threads. At least not ones that match the standard specifications.

Here is a screen shot from your model. I’m using the “Dave Method” for which Box posted the link to his tutorial. I made a component of your flanged thingy, made a copy and scaled up by 1000. I drew an M4x0.7 screw that is plenty long for the application. I’ve drawn it as an external thread but I used the specs for internal threads since that what it’ll wind up being.

I fixed your flange thing because it had some internal faces that prevented it from being a solid. Then I placed a copy of the screw where you indicated the hole should be.

I used Trim from BoolTools2 to create the threaded hole but you could explode the screw component and intersect faces. Then erase what isn’t needed.

After the hole is cut and threaded, delete the giant copies and return to the original. Here is the original component next to the screw you had made.
Screenshot%20-%2011_4_2019%20%2C%209_49_56%20AM

Probably should chamfer the edge of the hole so the thread start is better and you don’t have a fragile knife edge, too. I’d do that the same way with a chamfering “cutter”.

Will you please update your profile? It’s useful for giving you help when you ask for it. We’ve asked you to do this in the past but you still haven’t done so.

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Thank you for the help. I really do appreciate it and am sorry that this is a redundant post. I don’t mess with sketchup too much anymore and didn’t think that the last post had any useful information but that was wrong on my part. I will look into the Dave method.