Personally, I think familiarity with a variety of materials and techniques to save, repair, rework, refinish and such are all part of being a bowyer. But so is understanding when something can be saved and when attempting to do so will be time wasted. That said, there are countless lessons to be found in failed attempts, and first hand experience is the best way to learn what works and what doesn’t. Open communication with other bowyers can help, but my best mentors, while a great help, always allowed me plenty of room to fall down… and right myself :^)
Jayman, I will try to answer your question regarding different “forms of weak spots” and success with the wooden patches.
I have had good success so far with the wooden patches as described by Dean Torges, but I’ve been quite discriminating about if and where I use them. In my opinion, there are qualifiers that can largely determine their degree of success… and failure.
First, as noted, they must be executed flawlessly. Dean is likely the most meticulous, and discerning bowyer I know, so yeah, they tend to work for him :^)
Second, not all chrysals and frets are created by the same means, and whether or not this type of wooden patch will be an effective complete fix depends on them to some extent.
Let’s take a single fret across part or most of the width of the limb for instance. It could be the weakest single spot where the belly caved in, in the middle of an ‘area’ of weakness, say, 3 - 4” long or more. A hinge doesn’t hinge at a single point, it’s a weak ‘area’… with the fret(when a single fret is the result) happening at the weakest point within that area. Now, grinding out the fret and say 3/4” to either side of it in the process and perfectly executing the ‘Torges patch’ is effectively grinding out only the center of a larger weak, compacted area, and so is not assuring a complete fix. These are the patches that are more prone to try to push out, lift at the edges, fret to either side of the patch, etc. Much depends though, and in the end, even if executed flawlessly, sometimes they WILL work, sometimes they’ll work for a while and then fail, and sometimes they just don’t last worth a darn.
But on the other hand, this same wooden patch technique has much better success, and can affect a trusted, long term fix if the fret starts say, at a small knot or remnants of one… or something similarly specific, isolated, with otherwise uncompromised wood(not overly thinned or compressed) in ‘the area’. The more of the root cause the grinding removes, the greater its chance of success. Ideally, we grind it ALL out and the patch on such an occasion will put good wood against good wood all around it and we can continue as planned. Fixed…. Every bit, good working limb.
Also, I try to match the wood in the patch to the wood in the repair area as far as, quarter sawn to quarter sawn for instance, same ring size and density, moisture content, even use wood from the same tree if possible.
Now, multiple chrysals over a larger area? That’s beyond the scope of the wooden patch. Unless the chrysalling was caused by overly thinning of an area or improper tillering techniques, then it is likely due to inappropriate design for the wood species used and I would drop it and start another with the needed changes… but that’s me.
