Drilling Bores

[Wayne Fisher]

I'm interested in turning my own GHB and SSP, but unsure how start the bores. What size do you the initial hole and using what? I understand the consept of D-bit drill rod but is that what you start with? I was planning a two drone SSP out of Black Walnut two start (I have lots of stock wood). Any help would be nice.
Wayne

[Reinhold]

hallo,
I usually start with a D-bit just undersized to the desired bore diameter. For a SSB you could take a 3 mm bit. After completing the bore I open up to the correct diameter using a reamer of the correct size. You can make your own D-bits out of motorcycle spokes or of drill rod.
You need very sharp bits and a slowly turning machine and you very often have to clear out the bore.
Boring a chanter of about one foot length takes about ten minutes, depending on the wood.

with the best wishes
reinhold

[Gajdar]

I usually use a center drill to start D drills. They mount in the tail stock and are very stiff, so you get an accurate starting hole. I use a center drill that will produce a tapered start that is larger than the D drill, so the edge of the drill has something to catch.

Which raises a good point - always either leave a bit extra on the end that is removed during final finishing to allow for tool chatter and other unexpecteds, or plan to add a decorative bit on the end to cover the chewed up end.

A handy trick here is to make the decorative end with a mortise that hides the tennon on the end of the drone. Then your tooling marks are nearly invisible, which baffles the uninitiated ("How'd you get those bone rings on there?" You stack them up and then cover it with the end piece, but let them speculate, some of their methods are pretty amusing) :D