Domino Crib Sheet - How do you glue? and other crib sheet topics

[PaulMarcel]

Slowly getting through some recorded video...

In my Domino XL DF-700 review, I mentioned a 'Domino Joint Encyclopedia" forthcoming.  That sounds too authoritative for me hence the high-school crib sheet

This is the first video from that pile of recorded video.  The rest of the video will be released in small bites under the label 'Domino Crib Sheet'; if you visit any crib-sheet page on my blog, it will list a table of contents above the entry linking all the crib sheets.  Wish it was that easy back in Arizona History class (yeah, they made me take that...)

Some people put glue in the mortise, some in the mortise and on the Domino.  Some just drip the stuff all over.  I'll ignore the third group and focus on the first two.  This video does a glue-up experiment for strength.  If you've wondered what it's like doing glue ups "like them", give it a look.  I show how I did the experiment so you can decide if you don't like some aspect of it thinking it fouls the numbers.

Here's a link to my blog entry on this video; again, it will always show a full list of the other entries as they are released to the Internets.

Domino Crib Notes - How do you glue?

Uhm... sorry 'bout the shirt  [eek]

 

[Administrator_JSVN]

Looks like we all need to pitch in to get Paul-Marcel a gym membership.  [poke] Of course, I can't talk much being a desk jockey myself. But, I do have some killer muscles in my mouse button finger.  [big grin] [blink]

Nice video on what's sure to be an opinionated topic. Well done!

PS - I always thought of you as that nice guy that you'd want to have as a brother-in-law until that shirt showed up. Fortunately, I don't have any sisters.  [tongue]

 

[Zacharytanner]

Paul,
As always another interesting and pertinent video.... I will also be gluing the mortise and the domino after watching your video.
I have another question for you as well... Do you use the narrow mortise width on the first mortise and then switch to the medium width or do you use the medium width for all mortises in an edge glue up?

Thanks,
Frank

 

[PaulMarcel]

Thanks, Frank... for panel glue ups, it depends.  If the panels are glued long-grain to long-grain (99.9% of the time they are), the Dominos are just for alignment so I pick n choose where to put them based on how I'll assemble.  At least I don't want a Domino every 6 inches along a long panel to align and, moreso, apply glue.

Since I'm cherry-picking the Domino locations and not marching across via cross stops or fence pins, I just use a pencil line and use exact-size mortises.

Something else I've done on long panel joints: using 5x30 Dominos, mortise the first and last holes on one side of the joint to 12mm depth; the rest are 15mm.  On the other side of the joint, the first and last are 20mm deep (rest 15mm).  Now when you assemble the joint, put the Dominos in the first side, stand it up, then put the second side on it.  The first and last Dominos stick out further so get them in their mortises; it should then just drop down nicely onto the others.  The benefit there is if you work alone since the first Domino will be engaged in the board and keep it from slipping out of alignment while you work the other end.

 

[peter halle]

Sir Paul,  (a title bestowed by me which really doesn't mean anything but sounded ok for this post but which will expire at the end of the day which is unlike "Ick" which will carry on forever)

YOU ROCK!

I learn something new every time you do a video / post.

Thank YOU!

Peter

 

[Zacharytanner]

Thanks, Frank... for panel glue ups, it depends.  If the panels are glued long-grain to long-grain (99.9% of the time they are), the Dominos are just for alignment so I pick n choose where to put them based on how I'll assemble.  At least I don't want a Domino every 6 inches along a long panel to align and, moreso, apply glue.

Since I'm cherry-picking the Domino locations and not marching across via cross stops or fence pins, I just use a pencil line and use exact-size mortises.

Something else I've done on long panel joints: using 5x30 Dominos, mortise the first and last holes on one side of the joint to 12mm depth; the rest are 15mm.  On the other side of the joint, the first and last are 20mm deep (rest 15mm).  Now when you assemble the joint, put the Dominos in the first side, stand it up, then put the second side on it.  The first and last Dominos stick out further so get them in their mortises; it should then just drop down nicely onto the others.  The benefit there is if you work alone since the first Domino will be engaged in the board and keep it from slipping out of alignment while you work the other end.

Paul,
Thanks for the response and GREAT tip on the end mortises....I will try this SOON  ;D

Thanks,
Frank

 

[fritter63]

Paul, thanks for doing that demo.

But I have a few concerns about the control conditions of your experiment

- When you clamped the test together for curing, did you use multiple clamps? One centered over each domino, or did you just use one the like shown earlier. Ie, did you insure that identical pressure was applied across both?

- If you used two clamps, how did you ensure that each clamp was exerting the same amount of force on the joint?

- When you re-applied glue after splitting the test block, I think you may have negated the experiment, as reassembling the joint would no longer duplicate the glue squeeze out forces  that are normally in play

- Would have liked to see a third slot used with just glue on the domino

- I wonder what would happen if you pooled enough glue at the bottom of the mortise so that the domino would force it to travel up when pounded in? (In soft wood this would crack the joint - don't ask how I know that).

Fritter "I minored in statistics but I'd rather play with tools"

 

[txrpls]

Let me guess...  an engineer?  [big grin]

 

[John Stevens]

I just use a pencil line and use exact-size mortises.

FWIW, based on my experience, I strongly prefer to use only one pair of exact-size mortises on opposing sides.  You get all the benefit of doing it the other way, but none of the risk of misalignment.

The first and last Dominos stick out further so get them in their mortises; it should then just drop down nicely onto the others.

That's clever.  Would you get the same benefit by making only the first (or last) stick out further?

Regards,

John

 

[PaulMarcel]

I added numbers to your questions to make it easier to answer:

Paul, thanks for doing that demo.

But I have a few concerns about the control conditions of your experiment

(1) - When you clamped the test together for curing, did you use multiple clamps? One centered over each domino, or did you just use one the like shown earlier. Ie, did you insure that identical pressure was applied across both?

(2) - If you used two clamps, how did you ensure that each clamp was exerting the same amount of force on the joint?

(3) - When you re-applied glue after splitting the test block, I think you may have negated the experiment, as reassembling the joint would no longer duplicate the glue squeeze out forces  that are normally in play

(4) - Would have liked to see a third slot used with just glue on the domino

(5) - I wonder what would happen if you pooled enough glue at the bottom of the mortise so that the domino would force it to travel up when pounded in? (In soft wood this would crack the joint - don't ask how I know that).

Fritter "I minored in statistics but I'd rather play with tools"

#1 - I used one clamp centered on the space between the Dominos, but with a 1" thick caul.  Both should have had the same pressure over the Domino mortise area

#2 - just 1 so n/a.

#3 - I may be misunderstanding your question.  I applied water to one side, glue to the other then assembled the mortise block w/o Dominos in it.  After wetting and applying glue to the Dominos, I refreshed the glue in the mortises (which is something I usually do anyway; it's dry out here).  Then tapped in the Dominos.  After about 7 minutes that way, I put the block on the edge of the bench "Dominos up" and gently tapped the top of the board to slide it off the back; I didn't pull it up possibly moving the Dominos.  They stayed right where they were and the top had only a little glue that pushed up from the bottom of the mortise well and around the sides of the Dominos.  Other than some in the well, it was all pretty snotty so to me it was in its final position.  I topped with plastic wrap and the top of the board and applied the same clamp and caul for 3 hours or so.  I didn't add more glue after separating the blocks to put the plastic in.

#4 - What brought this up was a conversation with a friend about putting just glue in the mortise to save on cleaning squeeze-out.  I think if you put glue on just the Domino, most would wipe off onto the surface leaving a bigger mess to clean of squeeze-out so it wasn't really relevant to my original test goals.

#5 - I've had too much in the bottom that settled and the hydraulic pressure coming back makes seating that Domino really hard!

This seemed like a valid way (among many) to test the idea.  Certainly if any aspect of the test weakened the 'mortise-only' case, it did a great deal while leaving the other still strong.

 

[PaulMarcel]

The first and last Dominos stick out further so get them in their mortises; it should then just drop down nicely onto the others.

That's clever.  Would you get the same benefit by making only the first (or last) stick out further?

Regards,

John

There's still a benefit, but I prefer to have both ends in position so I can move down the board and get the Dominos into their mortises.  If you just have the first end longer and inserted, you still have to hold the board as you monkey with Dominos to get them in the mortises.  With both ends longer, it makes that part hands-off.  I usually do this on long panel glue-ups; short stuff isn't an issue.  The last time I used it was for a 12' long panel.

 

[fritter63]

Ok, I withdraw my concerns.

 

[Kev]

When's the compilation DVD come out? ... and the bloopers trailer  [big grin]

How are you going to cope if Festool diversify and bring out a food processor?

Kev

 

[PaulMarcel]

When's the compilation DVD come out? ... and the bloopers trailer  [big grin]

How are you going to cope if Festool diversify and bring out a food processor?

Kev

DVDs are so late 90s Streaming is where it's at!

A food processor?  Before software, I was going to go into culinary arts so bring it on!!

 

[Kev]

When's the compilation DVD come out? ... and the bloopers trailer  [big grin]

How are you going to cope if Festool diversify and bring out a food processor?

Kev

DVDs are so late 90s Streaming is where it's at!

A food processor?  Before software, I was going to go into culinary arts so bring it on!!

Damn you Paul Marcel - what can't you do ?

Painting?  [big grin]

 

[peter halle]

Kev,

Check out reply # 23 in this old thread:  Humorous November 2008 Contest

Peter

 

[Kev]

Kev,

Check out reply # 23 in this old thread:  Humorous November 2008 Contest

Peter

Ha!

There's so many wrongs in there - despite that, I'm extrapolating and thinking of further evil Festool purchase justifications.

EXCELLENT!

 

[RC]

A food processor?  Before software, I was going to go into culinary arts so bring it on!!

So when can we watch your streaming version of Modernist Cuisine?  [popcorn]

And how's the review of your scroll saw coming together?

 

[davee]

I added numbers to your questions to make it easier to answer:

#4 - What brought this up was a conversation with a friend about putting just glue in the mortise to save on cleaning squeeze-out.  I think if you put glue on just the Domino, most would wipe off onto the surface leaving a bigger mess to clean of squeeze-out so it wasn't really relevant to my original test goals.

The video was interesting and informative.  I understand your rationale for not putting glue on only the Domino.  However, this is the approach that I most frequently use.  It was demonstrated at the Festool training in Lebanon.  Brian's approach was to squirt glue onto a scrap piece and then smear the domino in the glue and insert into the slot.  The next domino was used to scrape away excess glue and then go into the glue itself.  To your point, this does require some squeeze-out clean up.  However, it is a faster approach overall (in my opinion).  I've not seen any degredation of strength - I suspect this is because of the glue in the domino grooves.  This is just throwing out another consideration, not questioning the results you demonstrated.  The great difference in strength certainly warrants consideration for gluing both.  Thanks.

 

[PaulMarcel]

A food processor?  Before software, I was going to go into culinary arts so bring it on!!

So when can we watch your streaming version of Modernist Cuisine?  [popcorn]

And how's the review of your scroll saw coming together?

Wish I had a chance to eat at ElBulli before it closed last year.  Saw so many programs on his cooking; he's like Harold McGee to the twelfth power.  Wish the tomb on his methods wasn't the cost of a Rotex or I'd have had that long ago! But then I'd need room for a liquid nitrogen freezer for pea purée, balloons for aromatic desserts, and a funky Tesla-coil like thing to make string sugar.  It's no wonder the restaurant was open 6 months of the year with the other 6 busy doing R&D!

For the scroll saw, I'm so behind on things right now!  But it's on the list; I have a neglected entertainment center to finish first!