Having recently started to look at George Nakashima’s work again, I have a question on the “butterfly” patch (lock). It is used to “hold” a crack or a check, how thick is the actual “butterfly” (to be structural rather than aesthetic)? Anyone know?
Thanks,
Donkey
eww…don’t poke me there, it hurts.
Replies
About one third of the thickness of the material it's going to be inlaid into.
Not that I do it often.. Just on occasion.
On a thick slab (over a inch or so) I go all the way through.. Not sure why I do or if it is the 'proper' thing to do.. Just me...
I believe I saw a picture of a slab table by George Nakashima and it had a butterfly that went completely through the wood.. I think?...
Anyway.. For strength.. Why not?
I building a slab table at this time in the Nakashima style. To help I ordered this book (link below). It should be here Friday, I'll let you know if it mentions anything about thickness of the butterfly. Amazon has the book for $30.00
http://search.barnesandnoble.com/booksearch/isbnInquiry.asp?userid=EW3OO5hA0Z&isbn=0870119036&itm=2
Dale
Edited 11/3/2005 8:57 am by Timberwerks
If you are looking for any how-to info, this is NOT the book you want. It is much more of a life story of Geo. Nakashima. That said, the pictures are worth the cost of the book and I'm glad I bought it.
That's what I kind of thought. I'm interested in reading about how he selects and has the slabs cut. I also would like to learn more about his design process. Do they cover these items in the book?
Dale
I have this book, worth having. More of a philosophy of woodworking and life in general.
Thanks to all.
Donkeyeww...don't poke me there, it hurts.
Yes, it's a lot like Krenov.
The butterfly patch, or Dutchman, is structural, and so it must be thick enough that it has strength to resist furhter splitting. I never go all the way through as it is a PITA (to get it to look good on the bottom) and adds little. I generally make mine about 3/4" thick.
These are easier to cut in than you might imagine, esp. if you use a pattern and a guide bushing. Cut the pattern in plywood or mdf by jig saw from an outline you have made on the pattern from the dutchman, which is cut first. Make the pattern large enough so that clamping it in place is easy. The offset between the outer rim of the guide bushing and the router bit will make the hole too small, and that is what you want. After plunging to a proper depth, just shy of the thickness of your patch, then place the patch over the too small hole, and mark it well with a knife. Then simply pare the sides to fit, using the knife line to register your chisel for the final, fine cut. If you undercut it a bit, that is fine, as I use epoxy for installation, and it is gap filling, so the fit is perfect all the way (counting the glue) and have never had one move on me.
Alan
http://www.alanturnerfurnituremaker.com
Also, be careful about how big they are - you're setting long grain into cross-grain, and can get shrinkage cracks at the outer edge of the butterfly because it is preventing the board from adjusting to moisture content.
I used butterflies to reinforce joints in 2 inch thick boards a few years ago, and made the butterfles about 3 in long. I got some cracking at the outer edges - not helped by a too-tight fit!
Malcolm
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