Curved dovetails, different curves inside and out.

Re: Curved dovetails, different curves inside and out.

Nice exercise!  I would make a paper template, trace it onto the wood and make each cut as carefully as I could... As to what to do with it, my thought is that you should do whatever pleases you the most- trying to predict what others will like or appreciate is not in my experience a winning game...

-Howard

Re: Curved dovetails, different curves inside and out.

Before I tell how I did this, I would like those of you who like to cut pins and tails to imagine how you would go about it, and share your thoughts. I think the impetus for me back then, was seeing a box in FWW that had curved outsides, which got me to thinking through making it harder by curving the inside too. 

What I would do is :

(1) Prepare the tail and pin boards - begin with the pin board, then use this to shape the tail board. The profiles need to match each other externally when placed edge to side. This is the key to all. Should be straight forward after this.

(2) Trace the edge of the tapered pin board to the side of the tail board to create the baseline for the tails.

(3) Mark, saw and chisel the tails.

(4) Transfer tails to pin board.

(5) Saw and chisel the pin board

Done

Regards from Perth

Derek

Gosh you make that sound easy! 😁

I will point out though that since the inside curve of the pins end will need to be cut to match the inside curve in order transfer the tail onto, that isn’t the same curve needed on the outside shape, so the pins actually need to be cut about an inch longer so they can be trimmed off to match the outside curves after they come through. 

AND although YOU being Derek Cohen might have the eye , abilities and tricks to cut, keeping the side cuts on the correct plane when both sides and the end are no longer straight lines to stay square to, others may struggle a bit more! I hope you take that as the compliment it was meant to be, instead of an insult! 

But that isn’t quite the way I went about it, which I will share after giving a bit more time for others to think on it, and chime in. 

Re: Curved dovetails, different curves inside and out.

I would glue it up. The interest of the joints is still apparent and who knows, it could be your eternal residence.

Re: Curved dovetails, different curves inside and out.

I love this piece.

Fine Wood Working No. 234 (August 2013) had an article about Dan Faia building a Bombe' chest with the characteristic exterior curves and a few of your interior curves. I was ready to say you cut and made the joints and then, went back and formed the faces. It's how I would make the box, although my Scotch traits would be screaming "waste"!

By all means finish it as you wish. I would finish the lid, probably identify the calligraphy, and lightly glue the box joints. Or, do some Japanese wedges that can be knocked loose.

Thanks Bruce,

“identify the calligraphy, “Back in or around 1980 a lot of my work although original showed Japanese influence, so I carved my signature to look like Japanese kanji, which was refined a bit then became my logo that I’ve used ever since. 

Your thoughts on leaving the outside shape until after cutting the pins and tails might make keeping the cuts square to that face easier, but not how I did it. I’m pretty sure I shaped a board long enough to get all 4 sides from. I think I used a Sears molding head for the TS with the 3 straight knives ground to a fingernail curve. 

I was hoping Mr Tindall would chime in, since he has shared so much on cutting DT’s. I hope he hasn’t abandoned the WC community. ??

The tricks i used.

Whenever I’m needing to work with curves is to attach a flat piece of something like 1/4” MDF to the outside for the tails, inside for pins which has the same height and length. The layout for the planes for the sides of the cuts can be drawn to intersect with these storyboards which held them plumb and square or the desired angle to the table saw sled, then cut standing on end.