Thread cutting procedure fails miserably!!!

Sadly, my memory isn't what it used to be, it seems. I know I have
done this in the past, but admittedly not in awhile.
I am attempting to cut a 12 pitch thread on a 1" plastic shaft, and
although my notes on the subject are seemingly comprehensive and
complete, do not work any more. Please help out an exasperated
moldmaker.
I have extruded a 1" diameter cylinder 3" long and have changed the
view to show one end of the cylinder, I have sketched a circle to the
edge of the diameter, then, insert/curve/helix, after changing the
parameters to my needs, an isometric view shows the helicoil fine.
Now I need to make a plane normal to one end of the helicoil to sketch
the thread shape that I want, and this is where I stumble, and
badly. insert/reference geometry/plane yields NOTHING !!!! My notes
tell me to select the point of the end, then the helicoil. I am
unable to select anything.
Please tell me what fundamental I am missing here!!!!!! Maybe the
plane parameteres are set wrong??? The plane window never appears???

David

 

I find it difficult to know exactly what you have done, but I have
done this hundreds of times, and I did find it easy to follow the Help
for Helix section in SolidWorks.

The key to getting a sweep cut thread is to start the Helix at say 90
degrees (top of the Front plane) for the "Path", and then construct
the thread "Profile" also on the Front plane, so the Profile and Path
start off on the same point on the same plane.

Finally pick the Profile and Path & use the Insert/Cut/Sweep tool.

Depending on exactly how you want the thread to start and end when
molding threads, you may wish to specifically put the start and end of
threads in specific places with respect to parting lines or unscrewing
cores, etc., but it does work.

Bo

 

When I said "start off on the same point", I should have been more
clear. Make them start on the same plane & the start point of the
helix must start off on either the Profile line segment on the OD of
the shaft/thread sketch or the ID line/vertex of the thread sketch.

Bo

 

I thank you for your response.
I do know the principles involved in cutting a thread, however, my
basic question is ...why, after after invoking a plane, with Insert/
Reference Geometry/ Plane, and selecting the tiny yellow plane icon,
does a plane image not show. In the past, I distinctly remember a
small plane show surrounding the end point of the helix, and at that
point I had to select "normal To", so that I could make my sketch of
the thread shape. For this little plane not to materialize in the
first place , I must be doing something basic out of sequence here.

David

 

Under the View menu item is "Planes" checked?

Bo

 

No, worse than that. Hide all types was checked. I am truly a
posterchild for dumb.
Thank you Bo!!!
David

 

What i could understand from your problem is u r not getting a
perpendicular plane at the start point of helix.
if it so while creating helix set the start angle parameter to 0
degree and your right plane itself will come to start point of helix
starting point.

Hope it would help..

vivek