LouieAtienza's "Dovetails on the Flat" Technique, take 1

[michaelthomas]

Our kitchen design software (KCDW) has a nested dovetailed drawer module that out puts to AlphaCam. I build about 20-30 1\2" baltic birch drawers per week. All nested based, and the joints look fairly normal. (Typical 1\2 blind)

Because of the nesting......they always fit like a dream.

[louieatienza]

Our kitchen design software (KCDW) has a nested dovetailed drawer module that out puts to AlphaCam. I build about 20-30 1\2" baltic birch drawers per week. All nested based, and the joints look fairly normal. (Typical 1\2 blind)

Because of the nesting......they always fit like a dream.

While I am aware of the different software packages that contain dovetail drawer modules, to me the cost is prohibitive.

While it's fine for general cabinetry, there are times in woodworking where you WANT the ens of the tails exposed, like in a blanket chest, jewelry box, etc. especially with contrasting woods. Also, a hallmark of hand-cut dovetails is the variation and fineness of the pins. I can make the pins as fine as I want, up to 1/8" at the narrow end.

I don't know of any software package that has a dovetail module that cuts through dovetails on the flat, without need for whittling or adjusting afterwards. I know it can be done on a 5-axis, but I don't have that! Just working out of my basement, with no special software. Heck, I designed this in CasMate 5, which has got to be about 20 years old! Like mentioned earlier, I wouldn't use this for production, but for my one-off stuff, it beats the dovetail saw, scribe, and chisel...

That said, I made a new test piece in MDF, which is closer to 1/2" and the fitment is way better. Still have room to tweak; now my main thing is the .005" tip of the v-bit. My layout didn't take it into account...

[zool]

Absolutely brilliant.

Your geometric conceptualization is astonishing; especially considering that the cause of not perfect on the first cut was the materials.

[louieatienza]

Absolutely brilliant.

Your geometric conceptualization is astonishing; especially considering that the cause of not perfect on the first cut was the materials.

Thanks zool! I hope to experiment more with this method in the coming months. The trick is to use the same angle for the tails as the angle of the v-bit. So a 30 degree cutter would require use of 15 degree tails, and a 45 degree cutter should have 22-1/2 degree tails, and so on.

Theoretically, with a 90 degree bit, one should be able to make a mitered dovetail, which would be REALLY cool! Though I see it in my head, time always makes it tough to put idea to wood!

To note, if one had a router table and a 15 degree dovetail bit, then the PINS could be reverse beveled instead of the TAILS, and may havve a more mechanical advantage. I find however that the tails are easier to trim. However, you would not need to cut the clearance slots, if you were concerned with 100 percent fitment.

I posted some vids of the baltic birch cut in my YouTube channel:

http://www.youtube.com/user/AtienzaL.../1/ocNqwCRo4xE

[RomanLini]

I'm impressed and intrigued by your 3D shaped dovetails Louie. I found this thread through a link in your router thread as I don't normally browse the woodworking forum.

From an engineering point your dovetails will be enormously strong in one direction. Maybe you could cut more complexity so they "lock" something like a wooden puzzle block, to give strength on both directions.

Here's an idea! What about putting some round holes on the side where the 2 pieces can slide apart, so the holes are half in one dovetail on piece1 and half in the dovetail on piece2.

Then putting some small wooden dowels pins in place in the round holes? After that action, it is fully interlocked and cannot slide apart in either direction unless the dowel pins are removed. Just a thought.

[louieatienza]

I'm impressed and intrigued by your 3D shaped dovetails Louie. I found this thread through a link in your router thread as I don't normally browse the woodworking forum.

From an engineering point your dovetails will be enormously strong in one direction. Maybe you could cut more complexity so they "lock" something like a wooden puzzle block, to give strength on both directions.

Here's an idea! What about putting some round holes on the side where the 2 pieces can slide apart, so the holes are half in one dovetail on piece1 and half in the dovetail on piece2.

Then putting some small wooden dowels pins in place in the round holes? After that action, it is fully interlocked and cannot slide apart in either direction unless the dowel pins are removed. Just a thought.

Thanks Roman! Yes there is no mechanical strength is one direction. The tapered tails means precise fitment is crucial. However, there is more joint surface area than on a typical dovetail, which means more glue surface.

There are many ways of adding wooden dowels or pins to lock the joint in the other direction; a favorite of mine is to drill from the top corners after glue-up; your idea is another.

Another option, though a bit mroe difficult, is to make the dovetail in such a way that it slides together in a 45 degree path. This gives it very good mechanical strength in both directions, especially when glued. I propose that with some maneuvering, this cold be done "on the flat" a s well...

In more traditonal cabinetry, the drawers were made to pretty exacting tolerances; in fact, they were made so well that pushing them in caused a "piston" effect, as it was slowed down by a pocket of air. The case sides helped support the drawer sides as well. The stuff was handmade and not cheap, and people took care of their furniture.

Nowadays, most drawers employ drawer slides like Accuride or Blum or similar; and people typically slam their drawers shut. There usually is a 1/2" gap on each side of the drawer, whic to me looks horrid, but is the norm now. Only exception maybe would be the undermont slides. The "soft close" slides have become more popular now/

[Mountaincraft]

Louie..
One of the questions I planned on asking you guys at some point, was if there was a way to do dovetails on the CNC...

Excellent that you developed and posted this... Now if I could just understand how you did it...

You mentioned the files, but I don't see a link for them anywhere.. Did I miss them somehow?

[zool]

Louie..
One of the questions I planned on asking you guys at some point, was if there was a way to do dovetails on the CNC...

Take a look at this and the other suggest youtube pieces: [nomedia="http://www.youtube.com/watch?v=ZGEYO1g6ZcU&feature=related"]YouTube - ‪cutting dovetails on cnc‬‏[/nomedia]

[Mountaincraft]

Take a look at this and the other suggest youtube pieces:

I'm not gonna be able to mount anything on end like he did at this time..

Although I have already been thinking that when I build the steel table it would be nice to have a pocket in the middle with a clamping system that would allow me to do so...

So for now, Louie's method is intriguing...

[louieatienza]

I'm not gonna be able to mount anything on end like he did at this time..

Although I have already been thinking that when I build the steel table it would be nice to have a pocket in the middle with a clamping system that would allow me to do so...

So for now, Louie's method is intriguing...

I have to get the file off my shop computer first, and then I'll upload it here. I do have it psoted on the Vectric forum.

If you decide to make a vertical clamping jig for your router, I suggest putting it on one end, to simplify loading/unloading. The vertical method is definitely the more efficient way!

One thing that would help: milling the "bevel" or "draft" with an 30 degree bit using the coventional method is slow, and there's a risk of breaking the bit tip. I'm looking into programming the paths in OneCNC using its open pocket toolpaths, where I approach the final shape from the outside in, and rest-machine the sharp corners. Or better yet, if I made a 3D model of the joint, I could rough out the part, including draft, with a straight bit, and finish off with the V bit. Of course, when I have the time...

Also, this maybe one job where HSS bits may actually be better, since thwy won't chip as easily as carbide, are sharper initially at least, and cheaper to replace when dull.

[zool]

Have you seen these: Flexible Stream ? Digital Wood Joints

[Mountaincraft]

Have you seen these: Flexible Stream ? Digital Wood Joints

First of all.. Thanks for that link.. Bookmarked! And very awesome!

But still, most of those don't allow the joint to be appreciated from the outside of the box by the casual viewer... even though they are beautiful and obviously seriously strong joints.. The cool thing about Dovetails, is that they capture the eye.. especially if two different woods are used..

I just need to figure out how to use the ideas on that page so that they are visible from the outside of the joint.. Because they are definitely cool and organic and strong and doable with CNC...

Although they presented 'one' idea that was 'somewhat' like a dovetail in the aspect of being visible... Nonetheless..Very cool and worth exploring... a couple of the more complex butt joints would look really nice with different woods...