Un-Safe way to make Domino tenons

[MacBoy]

.

Please see the comment by Crazy Race Guy down below on why this is UNSAFE.

For making long strips of Domino tenons, this happy fella has a simple 5-minute holder to safely use the router table.


(30-sec video)

 

[SitkaZach]

Just my two cents...I don't usually think the sides of a domino offer much. I'll just cut a wider domino with the machine, and then rip the domino square sided. Occasionally I'll take a few passes with a low angle block plane and give the sides a rough chamfer. It's nice to have some extra wiggle room on the sides when gluing up a large number of dominoes, and extra width also gives space for any extra glue. The top and the bottom of a domino are structurally enough for most of my work, small and big—unless I really want perfect alignment—and even then, that's usually just a matter of adjusting while clamping.

I fret the near perfect thickness of the domino. To my mind that's the important factor. In softwoods, I'll do a test, and sometimes leave them just a fraction of a hair thicker for snug alignment. Especially in larger thickness dominoes from the XL.

 

[MacBoy]

I don't usually think the sides of a domino offer much

agree

Squared-off tenons will be just fine.

I was simply thrilled at seeing a simple and safe solution for any future router table operation for using a profile bit.

 

[ChuckS]

Where added structural strength is desired, for example, in a butt joint, or where precise alignments are needed in a narrow to narrow mortise setting, full-width tenons are better than squared-off ones. Three-way miters are another joinery example where squared-off tenons may not be ideal.

 

[luvmytoolz]

I know some don't believe in even glueing the tenons in, let alone rounding the edges, but I like maximising the glue contact surface as much as possible and I love being able to use wider tenons, so I use the side profile cutters from findbuytools.com to machine the edge grooves easily and safely, and then use a pattern bit to do the grooves on the faces in one pass.

 

[ChuckS]

+1. Grooved/fluted dowels are better than dowels for dowel joints and the same goes for dominoes.

 

[Michael Kellough]

+1. Grooved/fluted dowels are better than dowels for dowel joints and the same goes for dominoes.

And spiral grooves have most withdrawal resistance, if glue was used.
I suppose you could make diagonal or cross-hatched grooves on Dominoes if max stiction was desired.

 

[rmhinden]

For making long strips of Domino tenons, this happy fella has a simple 5-minute holder to safely use the router table.

Nice video.

I did something similar when making some white oak domino through tenons, but I used a setup of four feather boards on my router table. That worked fine.

I suppose making a permanent jig would be good if one needed to make a large amount of tenons repeatedly over time.

Bob

 

[ChuckS]

I employed the feather board approach, too, one time when I needed to make my own. More than one permanent jig will be needed to make all the sizes if they are used.

 

[Crazyraceguy]

No one notices the stock being trapped between the bearing and the fence?!
This is a major no!
Bury the bit in the fence, align the bearing to the fence and then run the parts through.

 

[MacBoy]

No one notices the stock being trapped between the bearing and the fence?!
This is a major no!
Bury the bit in the fence, align the bearing to the fence and then run the parts through.

Thank you for catching that cardinal sin.

I was overtaken by the simplicity of the long tenon trap.

I have updated the original posting to alert people on the UNSAFE technique.

Eyes and mind is now wide open.

 

[onocoffee]

No one notices the stock being trapped between the bearing and the fence?!
This is a major no!
Bury the bit in the fence, align the bearing to the fence and then run the parts through.

What the amateurs don't notice, the seasoned pro sees immediately. This is why I come here.

 

[derekcohen]

I make custom dominos since the standard width limit the joinery needed.

Stock is sized in rectangular lengths, using a thicknesser-planer, and then the edges are rounded on the router table ...






Domino-made mortises ...



End result ...



Because the tenons were used in through mortises, the perimeter of the domino needed to be smooth (rather than grooved for glue to escape).

Regards from Perth

Derek

 

[luvmytoolz]

Very nice results Derek!

 

[PaulMarcel]

While I've made square-edge tenon stock for custom widths, I generally like to make them exactly match the mortise width, including the roundover. Usually, I use a roundover bit that's close as the inexact radius leaves a little glue escape in each corner while the overall width of the tenon is more or less exact. To me, this avoids needing to add grooves to the surfaces to allow for squeeze-out. If you're putting the grooves on, you could exactly match the roundover radius with some bits from Woodpeckers.

 

[luvmytoolz]

To me, this avoids needing to add grooves to the surfaces to allow for squeeze-out.

But what if you really, really, like the grooves? ;-)

 

[Packard]

And spiral grooves have most withdrawal resistance, if glue was used.
I suppose you could make diagonal or cross-hatched grooves on Dominoes if max stiction was desired.

I’m not sure I agree with that.

The grooved, fluted dowels are heavily compressed during fluting process, which I assume is a rolling action.

I tested the fluted dowels by drilling for them and then applying water-only and allowing them to dry in the joint. The wood of the dowels expanded enough that it was nearly impossible to separate the joint. It required a mallet to do.

(I would note that I cannot state with certainty that the dowel expanded to make the joint strong or if the plywood expanded to accomplish the same. I suspect that it was some of both. But flattening the flutes seemed to have no effect on the holding power, so I remain comfortable with my process.)

The reason I tested was for some joints I wanted to do a dry-fit that was easily assembled. I roll the fluted dowels on a hard flat surface with a wide, fine, metal working file. It flattens down the flutes and makes assembly easy. But I wondered if it compromised the joint to use those dowels. My water-only test convinced me that it was not a problem.

My dowel jig, designed for cabinet making and sheet goods, has a 32mm spacing between holes. I generally utilize all of the holes, which means that pulling the joint together can be challenging. If I am assembling base cabinets, I will flatten the flutes.

I am not sure if the helical fluted dowels are similarly compressed. I believe they are just milled for the grooves.

I would have to do a water-only test comparing the two types of dowels. The last time I ordered dowels, I got 1,000 8mm dowels and I have a lot left. I am not highly motivated to perform that comparison test.

Addendum: I was under the impression that Dominoes manufactured by Festool were also heavily compressed and when they absorb the water from the glue, they will expand. So I am not sure home-made dominoes are a really good option.

Taylor Tools offers discounted dominoes. I’m not sure that they compress their dominoes. I suspect they make then much like shop made dominoes are made. But buying them bypasses the safety issue.

Taytools Beechwood Loose Tenons for Festool Domino DF 500 and DF 700 | Taylor Tools

Taytools Beechwood Loose Tenons for Festool Domino DF 500 and DF 700

taytools.com

I have a tenoning jig for my table saw and a mortising jig (I think “Delta”) which I have not used in ages. Aside from the satisfaction of knowing I built something with a mortise and tenon joint, I find that dowels are faster and adequately strong for my work. (I actually made shaker drawers with rails and stiles joined with full saddle joints. I have no idea why I thought that was a good idea. And I am the only one that seemed to have noticed that detail.

 

[Michael Kellough]

I doubt with spiral flutes on dowels make any difference in withdrawal resistance is water is used instead of glue.