Stop a sec, Cheers. Yer doing ok, but there are a couple of major, but easily overlooked things going on here to think about before you finish.
1. Backing is up to you. I have seen a decent number of ipe self bows. BUT, Ipe grain is notoriously hard to read. If you took the glass off the front and are looking at finishing the bow without backing, take a LONG slow look at the back, in good light, with a magnifying glass. Ipe is hard, stiff, and has great tensile strength, but if the grain is bad, that just means that when it goes, it goes.
2. On long string or braced, youy NEED to pull the bow evenly. On your posted pics, it is obvious that the tiller stick is NOT 90 degrees from the center of the bow, AND it is different one each photo (unless the photos were taken at much different angles, or the bow was turned one way or the other).
Pull the bow to a notch and make sure the cradle on your tillering stick is in exactly the same place each time,
AND that the same spot on the string goes in the notch each time,
AND that the part of the string that goes in the notch is exactly behind the place on the handle that goes in the cradle. Mark it.
3. It looks like your bottom limb is longer than your top limb. Generally, for this style of bow, you want your limbs the same length, or the top one slightly longer and bending slightly more.
4. NO ONE can really tell you what proper tiller should look like from only the side. We NEED a front view of the bow, and stats like width and length to really help nail it down.
5. If your backing lifted, why? did you use the same glue on the handle build-ups?
Yes, you can leave the tips thick. The thicker they are, the narrower they can be. The width on most bows would be decreasing toward the tips, anyway. This means the width should be decreasing even more (or CAN taper faster, or narrower) be3cause your tip is thickened.
