Another Insane Inventor Moment

I guess you never realize how complex this is until you get something like this in your part designs.

http://i6.photobucket.com/albums/y242/Skywalker2D/wackythread2.jpg

Wow. I guess thats what they have to do to get it to be threaded. Man am I glad i dont do CAD.

Where are you getting 10 sides to fillet. As far as I can see there are only 2 sides to the threads for there to be filleted. Yet it still seems to be finding more. Could you post a before and after shot?

I think there are 5 threads on that lead screw.

Out of curiosity, how did you do that coil? Did you start on top of the lead screw and coil down? Or did you start to the side?

You’re modeling the threads on your part… How, excessive?

I think that he knows what it takes to win the Inventor award given his history. I am taking note of this simple yet ingenius idea.

There are actually 5 threads on this rod. It’s not a screw. We can’t reveal too much about the design. But we try to add as much detail as possible.

Wait, I take that back. I was just informed that it’s called a lead screw.

I’m not curious about how it is used (although I have my guesses), I’m just curious as to how you modeled the threads in Inventor. I gather that you use the coil feature, but I’ve tried to make lead screws in Inventor in the past and never got anywhere.

This is how I made the lead screw. It’s a little complicated, and I know I could show you a little better if you were sitting next to me as I did it, but as that’s impossible, this should suffice.

I started with a plain circle constrained to the origin. I then exited sketch mode and started a new sketch on a plane perpendicular to the first circle. On that plane I drew I second circle on the outside most point of the first circle. See:

http://img308.imageshack.us/img308/6538/leadscrewexplainok7.png

From this point I used the coil feature to make the swirly parts of the lead screw using the second circle and the z-axis as the axis. Then, since there are five threads in all, I circular patterned that feature around the z-axis. Here’s an illustration:

http://img293.imageshack.us/img293/3028/leadscrewexplain1ot4.png

Then I extruded a central cylinder from the first sketch. From here I put the famous fillet that you saw up there ^ on the model. The ends of the entire rod looked something like this:

http://img265.imageshack.us/img265/9302/leadscrewexplain2sq0.png

To remedy this, I used a cut extrusion for each end (as each end looked like this) from a sketch on the flat part of the central cylinder. This is where things got a little hairy. I had to figure out that the cut extrusion only cut in one direction, so it was necessary to make the entire model an inch longer than it actually is. I then used the both direction cut with a distance of 1 inch. This cut both ends inward .5 inches (equals 1 in) and also cut the extra stuff on the outside off to give the end a flush appearance.

http://img245.imageshack.us/img245/7724/leadscrewexplain3kj3.png

And there it is. Hopefully you understand this. If you have any questions to clarify the directions, don’t hesitate to ask.

Mike, that’s brilliant. Yes, I understood fine (mostly because of the helpful pictures). Thanks for the help :slight_smile:

-Daniel