Official Luthiers Forum!

I have been doing this 20 years and I learned a few things
A stopped using CA years ago. Not a fan but I know some people love it. Often a few years down the road you will see a yellowing happen.
B Duco is my glue of choice weldon is also fine.
C always set the purling and binding rout so that you have to sand to the binding not scrape. Scraping binding creates this very condition.
D wood or plastic is a personal choice. Plastic is more durable and more protective than wood. Wood glues just fine with duco and is more finish friendly
E When scraping often you get this smear effect and it will go away once you get the area leveled
F there is always more things to learn that what you know
G you can learn a lot from others even if it is not to do it that way.

When it comes to fit and finish , there are so many ways to do this. One must fine the technique that works for them
Razor blades and exacto blades seldom make a good scraper unless you grind it for that reason. A good scraper uses a burr not and edge.

you need to do a practice piece when setting up to do purfling. On the top pic the B/W looks fine what does look off is the outer binding that it was pinched off. You can check your binding channels with a straight edge on the side. The cut has to be parallel to the side not leaning out. That is where many go wrong especially on the backs , with the radius and taper that throws the router off to about a 5 degree or more angle. You may be thick at the base of the rout and thin at the top. Always check to see you are good. This is most likely at the upper bouts across the neck block.

these little details are the point that take you to the next level. Details always look for the details
best to you

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

If as others mentioned, that he has still not scraped far enough, is not true, then yes. Sounds totally reasonable to me.

The key I think to scraping bindings, and many things really, is to hold the scraper at an angle. Kind of like how you don't shove a plane head first into the work but rather angle it a bit so the first cut starts a shaving and carries it through.

Yes, keep scraping, keep scraping, all the way to China, and while you're there pick up some purflings that aren't defective. It might be the fault of the user, but it might be the fault of the purfling. Either way, if you have scraped and sanded it at or slightly below the level of the soundboard you might want to consider replacing it.

I think this is an important tip. I've noticed that some binding woods seem to be more prone than others to scalloping when scraping and holding the scraper at an angle can reduce or eliminate that. I've also noticed that the amount of angle off perpendicular that works best can vary from one wood to another. On the other hand, I had some curly koa binding that scalloped no matter what, and I had to do the final leveling by sanding.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter