Getting ready to build a staircase handrail out of rift-sawn white oak. It is going to be an "I" beams style profile 2 1/2" wide and 2" tall with a 3/4" grove along both sides for gripping. I am considering two ways of construction -- buy 8/4 lumber and dado or rout the groove or stack and glue three thinner pieces together to form the "I." Obviously, the single board would be the easiest option but wonder it would be prone to warping once installed. Two of the sections will be about 8 feet long and I don't the 5/8 spindle attached at the bottom will provide much strength in keeping it true. As far as material I will probably buy 8/4 either way since the 4/4 material is generally too short or poor quality. Their 8/4 material is very good.

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