DIYbanter - View Single Post

Jim Willemin

wrote in news:sc9hm4lb3ha1pd1jc2aq0ehr2ngboqtgma@
4ax.com:

I've got to join some 1x8 mahogany to "make them longer" for
converting a full size bed into a queen size. (That's a different
issue.)

I know how to make a scarf joint but am not sure on the angle other
than the more surface the better. From a realistic point it must be
some where between 45 degrees and 10 degrees or so. There must be a
point ofdiminishing returns where little strength is gained for a
shallower angle.

There are lots of sites from Google, but I have not foune one that
gives an idea of the angle strength relationship.

Thanks

I think in boatbuilding scarph joints are traditionally around 8:1 length
to thickness, or about 7 degrees; the joints are cut with a plane, the
boards stacked on the workbench and offset. That is, offset the ends of the
boards 8 inches, make a mark 8 inches from the end of the upper board, and
plane the angle on both boards at once. If it's strong enough to trust to
keep you from drowning, it's probably strong enough for a bed frame.