AutoCAD 2010/2011/2012 DWG Format

[#1]

I've tried several times, but can't figure out how to use sweep to successfully put threads in a hole.  Attached is the drawing with a helical coil and an object in two different orientations (A and B).  To the right of that, you can see the path they took for each.  The object rotated from the original position before following the path.  Tried changing the position of the object to sweep, but either it sweeps it 180 degrees from what it is already doing (still wrong) or the program says it is invalid and won't do anything till I put it back in the original rotational position and try again.

Any ideas of what I am doing wrong.

[#2]

3D model is very picky about which UCS you're using, if it doesn't sweep, try ROTATE3D that part and then sweep.

[#3]

http://home.pct.edu/~jmather/content/CAD238/AutoCAD%202007%20Tutorial%204.pdf

Pitch of your Helix is .025

Width of your tool is .0279

This will not work - Sweep would cause a self-intersecting body.

[#4]

This might work except that there isn't an "external threading tool" (fig.3 ) in AutoCAD 2012.

[#5]

Tried drawing the object in front (back), right (left), and top (bottom) and got the same results.  Tried a different position for the helical coil to start and used the same objects created in the different views, same results.

[#6 · Accepted solution]

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manofhg wrote:

This might work except that there isn't an "external threading tool" (fig.3 ) in AutoCAD 2012.

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The tutorial was written for 2007.

That refers to a geometry (triangular cutting tool) on layer named External Threading Tool.

So that layer name does not mean an AutoCAD command tool, I am referring to the triangular geometry as a "cutting tool" just like I would out on the shop floor.  The Helix is the path the tool will follow.

Use the attached dwg file and go through the tutorial I linked step-by-step.

Be sure to examine ALL of the geometry and ALL of the layers and read through ALL of the steps before actually creating anything.

[#7 · Accepted solution]

Redraw, make them all same UCS.

[#8]

Thanks for the help.  I was able to run the tutorial successfully, went back to my drawing was able to cut one thread, but repeating in another hole I must have done something wrong.  I made thread successfully with the part's layer turned off.  Turned the layer back on and tried to subtract the thread from the part.  The program thinks it was successful and I'm sure it was at something, the material wasn't exactly removed.  See attachment.  I have backed it out a few steps showing the thread to remove.

I have a lot of UCS problems, but am slowly figuring where I am and how to get to where I need to be.

[#9 · Accepted solution]

Your cutting tool has a linear edge while your hole is cylindrical.  The tool linear edge of the hole should be at least slightly closer to the axis of the helix than the edge of the cylinder.

Also you had facetres set to .5.  It should be set to 10 for the smoothest helix (do this before creating geometry).

Notice that your geometry is coursely faceted.

[#10]

Thanks, changed the facetres setting and decreased the radius a small amount and it worked well.