Drawing on a curved surface.

[jjseeker]

I am currently using ACAD Mech. 2007 and I need to draw a serpentine groove into a piston (3D of course) and I have to admit I'm at a bit of a loss here, starting to think it can't be done, could someone confirm either way for me and if it possible which tools do I use. I'm not looking for a step by step on how to do it, just a shove in the right direction. Thanks for any suggestions.
MQ

[jaberwok]

Hi MQ, welcome to AUGI.

Are you talking about a helical (spiral) groove? That has been possible (but not easy) for several releases of vanilla acad so I'm sure it should be possible in MDT.
If not, could you post a sketch of what you need?

[jjseeker]

Hi Jaberwok,
Sorry it took so long to respond I thought I had subscribed to e-mail notifications if someone replied.
Basically I have a cylinder shaped piece with a through hole on the radiused edge and a slot on the other quadrent points (see pic), the "o-ring" groove winds in a serpentine shape over the through hole and under the slot. I'm thinking of drawing it flat and then bending it around, unforunately I can't devote as much time as I like to solving these sorts of problems but it make life a little more interesting and me a little smarter, thanks for your interest.
MQ

[dzatto]

This is extremely rough, I only spent a few minutes on it. But, is this close to what you needed?
My groove is square instead of rounded, but with a little more tinkering I can make it look rounded.

[AkSledDog]

This is very similar to my project. Was just wondering how you did it?
Extrude a profile along a spline path?
I'm using AutoCAD 2011

[Kenny Koala]

Hi dzatto,
I really need to know how you did this. I have a very similar problem trying to draw fan blades. I am at a loss and need help desperately. Please help.

[dzatto]

Kenny,
I started using Revit about 5 years ago, and haven't touched Acad since. I honestly don't remember how I did it. I'll try to remember and report back if I do. Sorry.

[JD Mather]

... ... I'm sure it should be possible in MDT.....

The OP indicates AutoCAD Mechanical, not MDT (Mechanical Desktop).
MDT has not been sold as a product by Autodesk since Feb 2002 (given away for free with Inventor).
MDT was completely discontinued in 2009.

This is actually a bit of a tricky problem to get correct manufacturable geometry.
Here is a tutorial that might work in AutoCAD
http://home.pct.edu/~jmather/content/DSG322/Inventor%20Tutorials/Inventor%2011%20Tutorial%2011.pdf
there are now two easier ways to do it in Autodesk Inventor (Surface controlled Sweep or a built in Design Accelerator tool).

The usual Extrude on path or Sweep will not create correct geometry (this type of problem has a long history that I can link if anyone interested). The test is to animate with a pin in the groove and check for interference.

[jaberwok]

The OP indicates AutoCAD Mechanical, not MDT (Mechanical Desktop).
MDT has not been sold as a product by Autodesk since Feb 2002 (given away for free with Inventor).
MDT was completely discontinued in 2009.
...


Note date of post. Where were you 5.5 years ago?