Est. 1998 — 27 years of woodworking knowledge
Question on butterfly repairs?
Barry Irby
>A friend does really fine turnings out of exotic blanks, some of which include amazing voids and bark inclusions. He says there was a magazine article, maybe five years ago, on installing butterfly patches into the blanks before they were turned. You install the patches to reeinforce the blanks and then turn them, leaving the remains of the butterfly in the piece.
Anyone have any information on this? What magazine? Where can I get a reprint?
Re: Question on butterfly repairs?
Keith Newton
>Barry, I didn't see the article, but I have made them, what do you need to know?
Here is what I do. I start by cutting the end off of a board of the chosen wood, to the length of the butterfly.
Then tilt the blade of the table-saw to 10 - 15� or whatever looks right to your eye, and set the height to half the length of the Bf. This works best on a right tilt saw.
With the grain up and down, and the fence set to the thickness of the board, or whatever you want the end of the wings to end up, make 4 passes against the fence.
Now you will have a long BF, that you can cut slices off of to whatever thickness you need for the project, until it is all used up.
For a turning, you will need to cut a concave arc to match your turning circumference.
I would glue it into place on the surface of the turning when it is near its finished shape, but in the rough to medium sanding stage with thick CA glue.
With a very sharp knife, outline the BF, then remove it by snapping it off, or with remover if it is too stuck. With a chisel, sharpen and deepen the lines, then take a router to remove the bulk of the waste, then finish with more paring with a chisel.
When you are satisfied with the fit, glue it in, and turn the lathe back on to trim it flush, and finish the sanding.
If there was a major flaw in the wood, I often take fiberglass reinforced packing tape, and go around it a dozen times or whatever I feel comfortable with before hollowing the middle.