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Hello all ,got a problem with the sides on my first build.I've sanded in prep for binding,mostly ok apart from one section on the lower bout ,when i run my hand around it i can feel a couple of humps or flat spots that are quite noticable,i sanded all round the sides with a straight edge held from the top to the back but it seems to be just this one area giving me problems,anyone had similar problems.Ive tried sanding where it feels like the high spots are but not making much progress.Any advice would be appreciated.Thanks all Rob

what kind of wood is it? Some woods will flat spot during bending. You can try and sand it a bit more and you can also "finish fill " to help.

_________________
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

Thanks for the reply John, the sides are indian rosewood,what do you mean by finish fill?

Typically these kinds of issues are low on the out side in the near middle of the rims (side) width and most happen in the lower bout area. This is often called cupping. This cause by moisture that was not cooked out during the bending and after cook if a Fox style bender was used. It can also be caused by insufficiently cured wood. As the rim dries after bending the moisture evaporates at a slower rate in the middle of the width than the edges this causing the wood to move. Some times this can be pretty bad but most often is little enough to sand or scrape out without getting too thin.

If you used a Fox style bender I will suggest you cut back next time on the amount of added moisture. IRW bends like butter. Really no or very little added moisture is needed.

Thanks Michael i think your'e right about using too much water when bending , i soaked the sides for about 20 mins and used a bending iron, what is the finish fill tecnique mentioned by John in the previous reply? Thanks again Rob

Howdy Roby,

Not a good idea to soak your wood. Especially IRW! I generally spray a very quick light mist on each piece and don't even
think that's necessary. In fact, I'm planning on trying Todd Stock's method of wetting the paper that I sandwich the sides
in to bend rather than spraying the wood itself. As for sanding the sides, If you're using a rigid block with sandpaper that
extends beyond both edges, I suppose that's fine but I typically use a wide cabinet scraper with excellent results.

_________________
Bill Hodge


One does not simply, own enough guitars!

Thanks Bill i'll know better next time! Still want to know about this finish fill , anyone?

Mahogany , rosewood and maple don't need much water. Black Imbya , you can't make wet enough. Some woods need water some don't. Some bend with low heat others darn near need to be set on fire. The first 1000 are the hardest to bend

_________________
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

Finish Fill
That is when you over coat an area to allow a transition area to help hide flat spots. Using an iron cause some issues until you learn the skills. Flat and riftsawn can also flat. Waterfall figure will usually flatten . I like to run the sides at .095 to allow some sanding shaping.
These are the mistakes that teach you the most. Working wood is just that , making wood to do what you need it to do.

_________________
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

Thanks John, i was planning to use french polish as a finish, is it possible to finish fill with shellac? Rob