Need Help With Domino 500 Selection on 2" Thick Material

[Rufnek100]

I'm still new to the Domino game and I'm looking at using my Domino 500 to edge join two 11" wide boards for what will be a 48" long coffee table top. The material is reclaimed antique cypress and is true 2" thick stock. My question is around the correct selection / usage of the dominos:

1) A single layer of 10 mm dominos
2) A double layer of 10 mm dominos
3) A double layer of 8 mm dominos

The "1/3 rule" as cited in the supplemental manual and the fact that its cypress leads me to think option 3 is the way to go. In this case, I think the maximum fence height on the 500 is going to force me to reference the domino layers off of both the top and bottom surfaces, correct?

This is probably Domino XL land, but unfortunately I don't have one (maybe next year!).

Thanks

 

[mouppe]

One layer of dominos- 8mm x 50 should be fine. The long grain glue joint will provide sufficient strength if the edges are jointed properly, the dominos will merely help align the two pieces. A second layer is superfluous (IMO).

Make sure you clamp it coplanar though, with equal clamps top and bottom.

 

[rvieceli]

That is an ideal glue joint, long edge grain to long edge grain. With modern glues that joint should stronger than the wood next to it.

the dominoes would be for alignment mostly. I wouldn't go double rows.

 

[jacko9]

A single row of Dominos to assist with the alignment during glue up.  The edge glue joint will give you all the strength that you need. Use plenty of clamps during glue up and rotate the direction of clamping every clamp.  I would use a clamp every 6 to 8" along the length during gluing.

Jack

 

[Birdhunter]

Whatever you do, do not reference off more than one surface. Dominos have about zero vertical "slop". Even the slightest variation in your wood's thickness could mess you up if you reference off opposing surfaces. From Halfinchshy's video, I learned to cut exact sized mortises in one board and wide mortises in the mating board. This technique allows for lateral slop.

I usually alternate grain patterns when I joint boards. One will cup up and the next one will cup down and so on.

 

[dfuller]

^ This.  Birdhunter knows his domino

 

[Rufnek100]

Thanks for setting me straight - in retrospect I should have initially considered the inherent strength of the joint, but I suppose part of having the tool is the excitement to use it. A classic case of "if you're a hammer, everything looks like a nail..."

And that's also great insight to always reference off of one surface when making double stacked mortises. My thinking was that as long as both horizontal planes of the joint are referenced off the same surface then I would be okay, but that makes total sense that only identical thicknesses of materials would allow that to work correctly.

Thanks again everyone - being able to work through this here definitely saved me from having to learn from making mistakes on my project!

 

[Birdhunter]

Aw shucks..... Most of what I know about using a Domino I either learned from Halfinchshy or by enlarging my scrap pile.

I do confess to "inventing" projects that allow me to use either the 500 or the 700 Dominos.

 

[Stone Message]

One layer of dominos- 8mm x 50 should be fine. The long grain glue joint will provide sufficient strength if the edges are jointed properly, the dominos will merely help align the two pieces. A second layer is superfluous (IMO).

Make sure you clamp it coplanar though, with equal clamps top and bottom.

I completely agree with this.

I have never used anything other than the narrow slot size when dominoing - even when doing long boards. There is very little movement along the grain. It would be different if I were breadboarding but I have not done that yet with my Domino.

Peter

 

[Birdhunter]

Peter,

I use narrow (exact width) mortises on one side of a joint and the next wider width on the other side. This technique allows for a small amount or error in making the mortises and I can move the two boards a small amount laterally before clamping them. Credit goes to Halfinchshy.

Doesn't your technique of using the narrow setting on both sides require perfect accuracy in placing the mortises?

I made a bunch of 8 foot long benches with the top boards Dominoed together. I'm not good enough to maintain perfect mortise placement over 8 feet.

 

[Rufnek100]

I'm in the same boat with leaving one side on the wider setting, although it's because I can't seem to get my reference line calibrated any closer than about 1/16" when testing my cuts; but that's been discussed in other threads. Nevertheless, at this point in my experience level I don't have the confidence to put 8 cuts on a long board using only the narrow setting - but it's nice to know that I can adjust the tool to compensate for my lack of ability at this point.

 

[mouppe]

My usual preference is one side on the narrow setting and the other side on the wider setting, with the exception of the first mortise which is always on the narrow setting so that my edges line up properly.

 

[Stone Message]

Hi Birdhunter and Rufnek100,

I take care when I mark up pieces and use a 0.5 mm propelling pencil. Also the standard domino in the standard (smallest) slot still has a tiny bit of wiggle room left and right - you can check this by putting a Domino slot in a gash piece of wood and put a domino into it. Then tap the domino on the left or right edge and you can make it lean over slightly.

I routinely butt MDF, often up to 2.4m (8 feet) long and have done tons of oak in lengths up to 1.5 m. If I ever find a problem with this I will be the first to post about it here on the FOG.

As I said in my previous post, if I were to do a long cross grain joint then I would use a standard (narrowest) slot on BOTH sides at the middle, standard slots for the whole of one piece and middle size slots for the rest of the other side. A similar concept can be used for solid wood raised panels by only putting a spot of glue in the centre part of the panel joint leaving the rest to float.

Peter

 

[Birdhunter]

Peter,

I admire your skill and your courage.

I know my limitations and I'll stick with the narrow/wide method.

 

[Rufnek100]

I could come closer to having one narrow mortise on both sides of the joint that all of them, but I'm going to stick with the narrow / middle setting method as well until I have enough confidence that everything is going to align. Right now that 1/16" calibration issue has me a bit frustrated so this way I can tap everything into position once set.

I also admire Peter's skill and appreciate his much respected advice!

And I agree - being new to the woodworking hobby, using a mechanical 0.5 mm pencil as opposed to a carpenter's pencil sure tightened up my work in a hurry by making that simple change. Although I think I like calling it a "propelling" pencil better - a bit more eloquently put me thinks. 

 

[Stone Message]

Just to add a bit about the 0.5 mm propelling/clutch/mechanical pencil...

About 6 months ago I bought a brilliant precision rule by Incra from the Woodworkers' Workshop here in the UK - if you do not have one already then get one at your next opportunity - trust me. In order to use it you need a 0.5 mm propelling pencil. It has revolutionised my marking up - especially for normal Domino joints (by that I mean not those along a length of board as in the subject of this thread). Anyway, the 0.5 mm pencil has now become my constant companion - I use it for most of my marking, all of the marking with the Incra Precision Rule and, of course, I take it to the pub with me.

Peter

 

[rvieceli]

Peter

Which Incra rule did you get?

I have been looking at those.

Thanks

 

[Stone Message]

I bought the Incra RUL300M Precision Rule - it is metric and 300 mm long. I imagine the equivalent Imperial will be a 12 inch.

I did expect the rule to be quite bendy due to the large number of holes and elongated slots and one really does have to take great care not to damage it. I am going to buy the 150 mm one soon for the shorter work. I think that Incra have really cornered the market for high quality, great value marking with this family of products.

I have said this before (and if it in this thread then I apologise) but this Incra rule is up to the quality of Festool design and engineering - maybe Festool should offer them in green.

Peter

 

[Rufnek100]

Interestingly enough, the Incra precision rule was one of my first "real" woodworking tool purchases over a year ago and was also what made me abandon the chunky square pencil I thought was good enough up until that point. Peter's right - if you don't have one, it's a fine fine tool- but, like Festool, it takes away the ability to blame my mistakes on bad equipment...

 

[Birdhunter]

Just a suggestion, but I have both the Incra rule and the Woodpeckers rule(s). The Woodpeckers rules are much easier for me to read and they come in both metric and Imperial. You might want to consider the Woodpeckers rules.