Plain and simple answer to this is he needs to stop accepting new work until he has finished the substantial backlog that he already has. He appears to be full of promises and little else except a great talent for tuning scales.
To be honest, I have no idea how many scales he has laying around, but I am sure from numerous posts that some have just written off the fact that they will ever see their scale again, tuned or not. Some have posted that they have been waiting well over a year. And what happens to your scale if for some chance, God forbid, something should happen to him where he could not work any more?
He also said that he would be offering finished scales for sale, or that he would be offering his own design. I have seen neither.
I would suggest that given the demand for his product, that he would be much better served by finishing the work he has on hand and then offering finished scales for purchase as they become available. He could offer a discount for your "core" if he wanted to have a stock to work from at that point without sourcing them.
He would make more money (people would pay more for a product that could be delivered now), he would have a ready supply of "core" scales to work with, and he would be able to shed his bad reputation for poor communication and terrible service.
Not trying to tell the man how to run his business, but...........
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