Dove tail jigging on the old SB ?

[birdsofplay]

Has anyone setup to cut dovetails on the SB ?

I figure it'd be pretty easy to program.
Cut in as far as is necessary, back out,
move over, do it again. A Nice little loop.
Same routine for finger joints, whatever.

We could even do 45Deg jointed decorative insert type passes.

But is it better to do each piece individually
or to jig them together and cut as a set ?

The wife wants a dresser and I have some time,
So ... wha da ya think ?
Got any inside tips/ time saving recommendations ?

Thanks

[jimt]

Bob,

I have cut variable spaced dovetails on machine with fairly good results. I think a much better job will be done when I convert to the R&P drive. I cut the dovetails in pairs but not how the jigs do it. I made a jig to hold either two sides or two front/backs at a time using vacuum clamping. The sides are held vertically and the front/back horizontally. They are both referenced off the bottom edges of the drawers with the zero point in the center of the fence that the bottoms register against. that way the program is set for one side in positive y and the other side in negative y values. I know it's difficult to describe so if you need some more info, let me know and i'll send you a .dxf file of the fixture I made. A word about cutting - I had much better luck making two passes per joint in the front/backs. Cut just shy of the two ends and partial depth towards the center of the piece and then go back and clean it up with a lighter cut. The thing i found important is to keep the z axis in position once you get it set. It makes for a faster cutting routine.

Good luck
Jim

[birdsofplay]

Hey thanks !

I do appreciate the notion about keeping the
Z "STILL" !

Hey, if you ar e willing I'd like to take a look at your jig drawing.

Re the two passes, um ???
I've heard about doing an initial cleanout with
a straight bit and then going back to do just the
dovetail part with the DT bit. It was to lengthen
the life of the DT bit.

[joa]

I want to make a triangle shaped box with two of the corners at 45deg. I've been racking my brain on how to make the dovetail or finger joints. I haven't done that much joinery :)

Any suggestions? Do I have to cut the "slots" with the work at a 45 deg angle or is there another way?

[bruce_clark]

Bob,

Re: the two passes, one with an endmill and then
the dove tail cutter.

That is the way it is done on metal. The surface
area of the cutter increases when the DTC is
doing all the cutting, causing "chatter" AND
shortening the life of your dovetail cutter
(usually metal cutting DTC are more expensive).
Plus, this give more of an area for the chips/dust
to go.

Now, for wood, I am not so sure. I would think
that the above principles still apply, but I have
to admit, I have NEVER cut a dove tail in wood.

Your milage may vary.

Bruce Clark
bwclark@centueyinter.net (mailto:bwclark@centueyinter.net)

[birdsofplay]

Joa ,

I've seen some decorative joining that just took the edges that had been beveled and glued and then the DT bit is passed thu the whole joint and
inserts placed in the slots. Kinda nifty looking.
Would that kind of approach work for you ?

Also thanks, Bruce, for clarification re metal DTs.

Um ??? where are metal DT's used ?
My imagination is trippin over this one :-)

[dale]

Bob:

I just finished programming a job with a dovetail in it. The part was a base plate for a jig grinder. The customer wanted to locate his fixture anywhere in a straight line along one axis. The plate was 12" wide by 22" long. I had to place a 60 degree dovetail along the 20" length. The smallest width was 1" +.001 -0 and was .260 deep. I first roughed it out with a carbide insert cutter. I then roughed out the dovetail with an old dovetail, removing .005 with a new dovetail cutter. To top it off we had to machine an undercut .015x.015. We also made 60 degree keys that were tapped to slide in the slot. when tightened the keys would lock in the slot.
A little long winded but an example of dovetails in steel.
Dale

[birdsofplay]

Kewel !

Just goes to show that the SB community
has some "serious" players in it :-)

[Ron B]

Bob,
The old 'Norris' style handplanes have the bottoms dovetailed to the side. Gotcha two stones with one byrd.

Ron

[jay_mack1@hotmail.com]

I'm also looking for a good site for dovetail layout drawings, and dimensions. If anyone knows of a good place to find the math for dovetails, I'd appreciate it.

[rgbrown@itexas.net]

Stickman,

I've always generated the drawings from the bit I was to use.

Ron