Spiral groove.

[rwleigh]

Hello all, i'm having trouble drawing this spiral groove on the drawing attached. I think i'm just missing something obvious, could someone give me a clue on how to draw this please.

 

[lrm]

The helix command should be a big help.

[rwleigh]

1 hour ago, lrm said:

The helix command should be a big help.

That's what i've been using but i just can't seem to get two concentric helixes as they should be in the drawing shown.

[lrm]

The image of the spiral is distorted as noted below.

Position the image so that the center is at 0,0 then lock its layer. CReate points above the center to define where the helix should pass. Make sure the helix center is also at 0,0. Create a CW helix of 3 turns. Drag its grips so that it looks like the red helix below.

 

Make a copy of the red helix (copy 0,0) and change the number of turns of the copy to 4.  Then drag its start and end handles as needed.

Use splines and or arc to complete the geometry.

 

 

[Dadgad]

Can the OFFSET command be used on the first HELIX? 

[lrm]

Quote

Can the OFFSET command be used on the first HELIX? 

Yes, a spline is created.

Rather than creating two helixes, one representing the centerline of the groove could be made and then offset used to create the two sides of the grove.

 

 

Edited January 19, 2023 by lrm

[rwleigh]

4 hours ago, lrm said:

Yes, a spline is created.

Rather than creating two helixes, one representing the centerline of the groove could be made and then offset used to create the two sides of the grove.

 

 

I think i prefer that option. Thanks for you time Irm, much appreciated.