In the event that your cosmetic threads are not on layers, you can use the SHOW,ERASE menu utility to selectively show or erase (not delete!) cosmetic features (including cosmetic threads) by drawing, drawing view, sheet, one-by-one,...
In regards to cosmetic threads, I was curious as to what everyone else does. When you have a threaded hole that is for example, .28 -32 UNC etc.. Do you make the cut .28 and the thread like .30 so that the hidden line shows up in the drawing or do you make the thread .28 and the hole .28? Let me know.
If I understand your question correctly. This is my thinking. I keep my models as simple and as close to life as I can. So I always make my minor dia. (drill dia. for int. threads) consistant with the manufacturing process. For example you use a #7(.201) drill (which is the minor dia.) for a 1/4-20 thread. So I make my cut .201 and thread .250
It looks like some people actually model the helical screw thread!! If you are doing this then make sure your supervisor doesn't see it!
While that kind of thing might be fun, it certainly adds no value beyond appearance. In fact, it uncessarily consumes your time, computer memory, and regen time. Keep it simple. For external threads, say a No. 4 Coarse (.112-40UNC-2A), simply create a .112 diameter protrusion. Then add a cosmetic thread (.112 dia) over the threaded length.
Likewise, for a blind internal thread, say a tapped hole with a No. 4 Coarse (.112-40 UNC-2B) thread, simply create a counterdrill (hole with drill angle at the bottom) with a 118degree angle. Then add a cosmetic thread (.112 dia) over the threaded length. Depending on how critical the depth is, you may not even have to model the drill angle. The latter method is preferred because of simplicity.