[Shop-talk] Helicoil in aluminum

[Bob Nogueira]

I'm about to install a helicoil in an aluminum block.   The tap calls for
drilling a 21/64" hole.  Since it is aluminum should I drill the hole just a
tad smaller?  If so how much?

Thanks Bob Nogueira

(" Mr Gaskell, how much is a tad?".  --  " more than a smidgen and less than a
bit")
     ----The Patio Garage.  1963