In a prior thread ("Last Thread(s) in Closed Wrap") William Colby mentioned laying out the taper offset for a closed wrap to account for the taper of the blank in a butt wrap. Conceptually, I would think you need to calcualte the ratio of the length between intersection points and the diameter of the blank. This aspect ratio (sorry to use sailplane talk) will determine the next intersection point and so on. Surely, there is an easier way to do this. (I know... there IS an easier way to do this and don't call me Shirley... LOL) There is a reference to a few issues of the Rodcrafters Journal, but I am not a member and I haven't called Dick French yet.

So, the question is... How do you lay out your butt wrap so that it takes into account the taper of the blank for a closed wrap? Thanks.

You pretty much said it yourself. It's the ratio of the two. There are some other mathematical formulas but I think they are pretty much based on the same thing. Often on blanks that aren't tapered very much I just add a mm as I mark each center or something to that effect.

I have thought about a pair of calipers that you could make that would hinge in the middle. You figure out the relationship of diameter to length and plot each measurement on one end. Then on the other you open it and set it on the blank and read the distance to the next center off the other end of the caliper. You'd have to spend some time in the set up of the tool but once you had it right you could set up any closed wrap with it in just a minute or two. If I wasn't such a procrastinator I would have already made one up.

Check back issues of the Rodcrafters Journal. There are several methods that require only a few simple measurements to give a good layout for closed wraps.

Get a copy of Dale Clemens's video.Dale shows the easiest method I've seen.