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On my harp project, every piece of would was hand cut, sanded, thicknessed, and bent by hand. No kit parts. After assembling the box and doing some scraping and sanding, I noticed shallow hollows and indentations. Given the hardness of the wood, they were a real pain to "flatten". Is this normal? I have heard of people using chalk to find them. Are there ways to minimize this? (maximize flattnes and uniformity.) Or is this a normal process in guitar building?

Mike

Use a drum sander to bring the material down to working thickness, and don't use too much water when bending the sides.

Cheers

Kim

Yeah it happens and the worst that I have ever experienced was with African "rope" mahogany where the ripples appeared where the "rope" figure was. Mahogany seems to benefit from being very stingy with the spritzing of water prior to bending.

Block sanding the sides is just part of building and is usually necessary to varying degrees with any guitar that I build. Just make pencil lines across the sides and sand with a flat block preferably longer then the side is wide until the lines are gone and you are good to go.

Wood is not perfect all the way across its face and as you can see , soft spots will react differently than harder areas. It doesn't happen all the time but yes it can happen. The wider the graining the more you can expect this to happen.
john hall

_________________
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

Anisotropic is what this is called.
Not having the same properties in all directions.

I find the thickeness of the sides has an affect on this.
Thicker sides develop it more easily then thin sides-thin sides flatten
as you bend them (a bit ) compared to thick sides.

The cut of the wood matters also !
Slab,quartered,rift ,


Mike

_________________
Mike Collins

So, what I am hearing is that it is a part of the process.

Roger that.

Mike

Exactly! If the sides were not flat, pores did not stay filled, binding channels were not even, neck/body joints had gaps - anyone could do this........ We are all insane I tell ya!!!

Thats good to know. Maybe I will build a steam box. (or get one)

Mike