Another Insane Inventor Moment

[Robert Thacker-]

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

[chris31]

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

[Molten]

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?

[Andrew Blair]

Originally Posted by Temper Metal

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.

[Daniel Brim]

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?

[Jak DiGriz]

You're modeling the threads on your part... How, excessive?

[Molten]

Originally Posted by Jak DiGriz

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.

[Robert Thacker-]

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.

[Robert Thacker-]

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

[Daniel Brim]

Originally Posted by Robert Thacker-

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.

[Mike Hvorecny]

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:



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:



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:



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.



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

[Daniel Brim]

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

-Daniel