Those cracks are from heating to fast to hot at once IN ONE PLACE. This damages wood cells at this place. The reflex pulled damaged wood cells apart at this place, CAUSING THE CRACKS. Sinew will do fix the wood cells,super glue will not pull the cells back together. STRING IT HOLDS THE CRACK TOGETHER. Why you can shoot the bow for a while. The suddun stop after each arrow aventally makes the crack bigger ,makes cells weaker with every shot.
The more you damaged the cells the deeper they go. Only hope is the cells ain't damaged to much there not to deep and you have enough wood left as to tiller they disappear. But this aneas still danaged you just can see it. So if it's for you finish it shoot it as long as you can. SOME A TIMES LONG TIME SOME TIMES NOT SO LONG.
I have to vent a bit. I'm sure this is going to set on a lot of toes. AND IT SHOULD. This only involves you bowyers out there. As a bowyer like any thing else you thrive to do your best with every bow. And bowyers like hunters don't like to be told what to do.
I understand all about heating bows. When I started and the first 10 years. I heated and bent 25 .30 bows. So I know about why your heating and bending bows. I DO THE SAME WITH NO HEAT AND HAVE FOR 15 YEARS. No doubt about it you can make your bow SWEETTTT looking by heating it just right TO IT LOOKS GOOD. Never give any thought about wood cells your damaging.
The one on the post is just exstearm done totally wrong. 99% the time you don't see what you've did to the cells. Like his bow it'll last for a while. The bows heated you don't see the damage will shoot. But not as long as it could have if it wasn't heated.
I heat very little and if I do it's only on non moving parts tips handles just to but them in line. Why because I look ahead a ways. I add my reflex wait green, quicker after it cut the better(easy er). You just need 2 saw horses and a floor and a ratchet strap. Ankor in the floor,ratchet the amount of reflex you like or need. Leave it dry like that. You have you reflex. I start out the 1# stave's so I a line as I build the bow. but it you have to Aline, YOU CAN HEAT THE HANDLE AND TIPS TO ALINE.You still have 2 unheated limbs.
2" 2 1/2 Inch's of reflex is about right for me. I can end up straight to 1/2 " of reflex. When finished.
Now to me its a NO BRAINER. Something to improve your bow making skills or shit heating works for me. Then you the best at bow building your going to get.None of your old bowyers used heat on working parts. Indians even knew it you heated the limbs your bow didn't last. Why you think they almost all used straight in bows. You can build them with out heat.
I know this isn't the way you were taught and the heating always worked for you. I not asking you to go to church or come to a devil worshiping meeting. Just talking about you being a beater bowyer not because I said so but if you have any commonsense then ITS A NO BRAINER.