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Maple wood crutch - grain across or vertical?

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Brett Buck:

--- Quote from: Dennis Toth on August 15, 2021, 07:26:53 PM ---OK, what I am building is a simple rat racer type ship. The fuse is from two pieces of full length motor mount stock, this forms the crutch, then a top and bottom block is added for some shape. The crutch pieces I have the grain running down the length but if you look at it from the end the grain is vertical for the width (1/2" x 3/4") I need in order to get the shape (similar to a speed pan shape). My question is really about the wood splitting, particularly when installing blind nuts?

--- End quote ---

    OK, I knew we were not communicating. I would probably rather have them vertical than horizontal but to be honest with you, I never even looked at which way the growth rings go at any point in the last 50+ years. As long as you drill proper clearances for the bore of the blind nut you shouldn't split it.

      Brett

Serge_Krauss:
I guess I too am having trouble understanding, because the question seems simple. I think the grain direction is most relevant to the direction of compression loads from engine mounting screws. 'seems to me that it should be lengthwise  and in the direction of the mounting screws. For a profile that would be perpendicular to the fuselage sides to counter compression loads from the engine mounting. I have never experienced splitting from blind nuts (I recess the plywood doublers to accept the blind nuts so that they are flush with the surface of the plywood. For a full-fuselage stunter, I would still orient the grain
 to resist compression loads from mounting screws.

SK

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