I have used them for making tongue presses out of Maple one of the threads had to be 12" long and stand up to a lot of stress the other threads were about 1" long for assembly two uprights and the handle and they worked very well as do the taps that go with them but you cant rush it and some times some wax will help but they wont work on open grained wood though you get bits fall of
Other things I have made using them are standard lamps, table lamps, clocks, Victorian mirror stands, easels and well I think that may be it