I've had lots of E-mail chat from a couple of guys making bows, one a Yew warbow, asking about avoiding knots and general tips. The other guy is making a Maple pyramid primitive and was asking about filing the nocks.
So here are some pics of how I do the temporary nocks in the Yew longbow I'm currently working on, it shows the general idea applicable to any bow.
I file out the grooves with a 'Permagrit' needle file, a small saw and needle file will do it, but the permagrit one takes the wood off quickly and doesn't clog. I don't groove the back of the bow at all, it's supposed to weaken the sapwood and potentially start splits, but I don't really think that would happen as there is very little leverage at that point. Same applies with horn nocks and tip overlays, I don't think it's really necessary on bows under about 70#. Obviously it depends on the wood and the bow style, so it's better safe than sorry. A thin wide flat tip would be more likely to split than a longbow style more round section tip. If a split did start on a flat limb, a binding of linnen thread with epoxy massaged into it would stabilise it, or for a more primitive look sinew and hide glue. I might add some more pics but Google Blogger is playing up this morning.