Daggerboard/case clearance

[lewisboats]

What are we looking at for clearance min/max between daggerboard and case sides? I laminated up 4 layers of 6mm plus I am going to coat it a couple of times plus paint...so say 25.4 mm or 1 in total. What kind of clearance should I use between the DB and the case walls...1/16"...1/8"...friction fit?

Steve

[PAR]

As close as you dare, considering it's wood. a 1/16" all around is a good tight fit, but if you have any swelling (not as much a problem with plywood) it'll jam.

Plywood isn't the best material to make blades from. Since half the grain is running in the wrong direction, it's not as strong as solid lumber, but is substantially heavier. If I had to use wood, I'd strip plank the blade, with (opposing annual rings) then a moderately heavy sheathing and a heavily reinforced leading edge.

Centerboards, rudders, daggerboards, etc. are best if made entirely from inert materials, which aren't subject to the ravages of the marine environment, don't change dimension with moisture content, etc.