On a straight end longbow does it matter if you run a .002 taper lamination on the back or belly? The rest of the laminations would be parallel.

I'm assuming your speaking core lam's , I have  done it both ways for the same design bow and it makes no difference as far as I can tell , the stack and taper are the same when glued up !

Either way works well.

If it's straight full length with back of riser also straight, the tapers have to be on belly so the riser doesn't rock on the center of tapers. This will give a big glue line at  riser ends.

Or put a reverse taper on the form (thin end to center) to make up for the tapers under riser.

Hope that made some sense!

Not sure what style bow you are making, but I always put them on the belly side (ASL).
That said, I don't think it would make much difference. But I cannot speak to the style of bows most guy's here are making, cause' I'm totally ignorant as to what Kenny is referring too!

To me a longbow ALWAYS has straight ends.  What other kinds of ends could there be that would still be a longbow and not a recurve???

Folks take a lot of latitude with terminology, best not to think in absolutes. For instance, "I" beam.
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To the original question,  if you put a .002 taper under the straight riser, you either have to fit the riser to the taper or have (on a 18" riser) a gap at ends of riser of .018"

Thanks guys.

Kenny I know exactly what your talking about. The belly of the bow would be all parallel lams and the back would have the taper lamination.

By straight end I mean the limbs would be straight no reflex or deflex in them.

In that case, I don't think it makes much if any difference.