Domino question - anyone "pin" Dominoes while the glue dries vs. clamping?

[LDBecker]

Probably a dumb question - not a huge Domino user - but I get some use. I was going to use my Domino 500 to build some face frames for some kitchen cabinets but the clamp time was a concern... and I don't have that many big clamps - so I went with a Kreg jig solution. The screws hold the joints while the glue dries, and no real need for clamping after you screw the joint together.
Recently I got a Grex 23 gauge pinner. These things are pretty cool, and can be used to help hold joints while the glue dries. I wondered if anyone had tried that with a Domino joint - pin the inside/non-seen part of the joint through the Dominoes on each side of the joint to "clamp" the joint while it dries.

Thanks!

Larry

 

[Nat X]

Well it's not really enough clamping pressure for anything more substantial than a door casing, and it mostly defeats the purpose of using mortise and tenon joinery entirely since you wind up with visible metal fasteners, so I can't imagine it's a popular workflow, but I've done it when I was building disposable things like mold boxes.

 

[LostInTheWood]

I'm not a domino user and I don't even use biscuits that much, but I have pinned biscuits on occasion and it works great for holding the work together while gluing up and assembling....., but that's about it.    It's absolutely no substitute for clamping and in your case, with the face frames, I would definitely clamp (or kreg).  Also, I've only used the pin assist when doing paint grade work.

 

[LDBecker]

I was thinking that pinning it on the backside of the face frame wouldn't show - certainly not as badly as the Kreg screw holes - they're not seen at all, so I won't even fill them. I took a 3-Saturday class on cabinet making at Rockler, and they pinned the doors after the profiles were routed. Just paint-grade poplar, but it worked well. We used Kreg screws on the face frames, so no need to pin anything there.
The face frames/doors I'm making are out of hard maple. I did one faceframe with Dominoes, but I need to work on my Domino technique - most joints were off by 1/32nd or so. As I say, I haven't used it much and, as careful as I try to be (yes, pushing slowly from the plug and firmly holding the fence down on the material), I still am off a bit. Patience...
I'm doing 25 or so face frames on this project, and a box or two (mostly re-using the old boxes) - I ended up buying the Kreg Foreman and the Kreg clamping table top. It's interesting using it on hard maple. The bit can deflect a bit, as can the screws, unless you use a LOT of clamping pressure - both on the drilling machine as well as the clamping table as you put the screws in. The joints are good, though. I'm pleased with the results so far.
Anyway - just a passing thought about pinning the dominoes. I may try it with some paint-grade projects. I've pinned some smaller projects and it works well.

Thanks!

Larry

 

[grbmds]

Even though I do love my Grex pin nailer, I haven't tried using pins to hold a Domino joint together while setting, but it seems to me that the purpose of clamping a joint while the glue sets, whether you use Dominos or a traditional mortise and tenon, would be defeated by using pins only. When clamping a joint, the two pieces of wood are being held together under side pressure from the clamps. That wouldn't be the case with pins. I doubt you could truly hold mating pieces together tightly enough to get the desired joint just using pins. If the wood tended to pull apart even slightly, the joint wouldn't be held together with the pins since pins bend easily from side to side. Pocket hole joints work well in combination with Dominos because a tightened down pocket screw pulls the pieces tightly together and is really a strong joint in and of itself.

I have always clamped the pieces together when using Dominos. Since I am not doing production work, I can wait for the glue to set and have a sufficient number and sizes of clamps.

Do a couple of test glue ups and see what happens.

 

[LDBecker]

I will do that when I get a free moment - under the gun on my kitchen project - antsy wife and picky measure guy for the quartz countertops. He found that a couple of my cabinet boxes were not previously lined up well, so I had to pull them off the wall and shim them to make them flush/square. And even though I'm replacing the face frames exactly, size-wise anyway, he wants it to be exactly as it will be when they install the quarts countertop. I understand, I guess... but I have to get this done quickly... while I'm working my regular job... going to burn a few vacation days to do it. It's much more fun when I can just take a few days at a time to do a project, rather than a couple hours here and there.
I will post back when I get a chance to try the pinning idea out. In THEORY, you're pinning both the wood and the Dominoes, so it should stay put - but if there's any stress on it at all, it would move and mess up the joint.

Larry

 

[Birdhunter]

I built a series of Ipe benches with Dominos. I kept the pieces clamped until the glue dried, but I also pinned the tenons for extra security.

I predrilled holes from the underside of the bench board on each side in the middle of where the tenon would go. I swabbed the mortise with alcohol, glued the tenon, clamped the boards, and then hammered a brad into the predrilled hole. No, the brad did not go through to the top surface. The benches have been in the weather for many years and they still are solid.

I would not forego the clamping. There is a chance the pin could split the tenon and thus negate its holding power.

 

[tjbnwi]

He found that a couple of my cabinet boxes were not previously lined up well, so I had to pull them off the wall and shim them to make them flush/square. And even though I'm replacing the face frames exactly, size-wise anyway, he wants it to be exactly as it will be when they install the quarts countertop. I understand, I guess...
Larry

Pull a string tight along the front edge of the face frames. This will allow you to line up the cabinets perfectly. Shim and screw to the wall while checking alignment to string.

For glue to "act" properly you need between 100 and 250 PSI of clamping pressure (according to Franklin). I don't believe the 23 gauge will allow you to achieve adequate holding pressure, even if you clamp then pin the joint.

Tom

 

[LDBecker]

Tom, thanks for the string idea... I have an 8' level also, so am using that to double check.

I appreciate the discussion on glue/clamping/pinning. I agree that the pins would likely not provide the clamping pressure needed to cure properly.

Birdhunter- I assume the alcohol was because that wood tends to be oiley? Haven't worked with that before. Reading up on it, it seems difficult to work with. I've done a little with teak, not my favorite, but beautiful.

 

[jimbo51]

I am not sure what role clamping pressure plays in Domino joints. The pressure  figure cited refers to joints like a half lap where a clamp holds the two pieces of wood in tight contact.

In Domino joints the clamps hold the pieces in alignment while the Domino swells to lock the joint tight. If the pieces are warped, then pins may not be sufficient. If the pieces are flat then pins may be enough to hold position until the joint is locked.

 

[grbmds]

Clamping serves the same purpose with Dominos that it would with a tightly fitting mortise and tenon joint; to hold everything tightly together until the glue sets to the point that force is no longer required. Obviously I can't prove that, but it's no different than a conventional mortise and tenon joint; just easier to make and assemble. I would never assemble a conventional mortise and tenon joint without clamping (or using something like a pocket hole joint to secure it). The Domino needs to be forced in its final position until the glue is set. Otherwise the risk is that the joint will slightly pull apart. It may hold OK in that position but it could slip just enough that it won't be the tight-fitting, clean joint we visually look for. Again, I can't prove this. I just see no reason to take the risk.

 

[Oldwood]

I have used headless pins to fix the domino in place when gluing wood support brackets on to support a counter top. The pin just keeps the bracket from moving away from the cabinet until the glue sets. As has already been mentioned the clamping force for the glue set is supplied by the interference fit of the the domino in the mortise.

I glued the domino into a vertical piece on the cabinet, let it set before installing the bracket. Then I glued the mortises in the bracket pushed it into place and pinned through the domino with the pins. It worked well and the holes disappear with a smidge of colored wax stick. 

 

[Nat X]

I am not sure what role clamping pressure plays in Domino joints. The pressure  figure cited refers to joints like a half lap where a clamp holds the two pieces of wood in tight contact.

If you're not sure then that means you believe the presence of dominos changes the physical properties of wood, and that is probably not true at all.

 

[fshanno]

An interesting question.  Give it a try and see what happens.  But you wouldn't have to use pins on the back side of a face frame.  You could even use little screws if you wanted.

I don't have a lot of clamps either but I work so slow that it's not a problem for me.

 

[jimbo51]

To Nat X

I am assuming that the clamping is on the sides and ends of the wood pieces and we are not talking about clamping down on the wood on each side of the face of the Domino itself. In that case clamps would be more effective than pins, but that kind of clamping would not be possible when joining large pieces of plywood for example.

Consider a simple T joint, end grain to side grain, made with a Domino. I think for that joint, the Domino provides most of the joint strength, not the end grain to side grain glue line.

I can even make a Domino T joint which has no glue outside of the Domino mortise and still have a strong joint. In this case, the clamping pressure has no effect other than to hold the pieces in alignment. The faces of the Domino inside the mortise pressing against the inside of the mortise are providing the glue joint of interest.

Or we could make a T joint, put glue in the mortise and on the Domino. Insert the Domino and clamp the pieces together. Then quickly place the joined pieces on an MFT table, clamp the pieces down firmly and then release the clamps holding the wood pieces together. I think we would still get a strong joint with the Domino.

I think the major force to be contained is that the swelling of the Domino may be uneven and that could cause the joint to open slightly. Is that uneven swelling force sufficient to overcome the holding force of 2 23 gauge pins?

I do not have a small pinner so I cannot do the experiment. Can anyone provide the answer to this question.

 

[SS Teach]

Welcome, if you watch Paul Marcel's YouTube videos concerning the DF 500 you will find he pin nails dominoes and tests them for strength. Pin nails and glue do make for very strong joints.

 

[Birdhunter]

I use my Domino 500 a lot, especially for a non-professional. I've never experienced a failure of a Domino joint. I've pinned tenons only on the set of outdoor Ipe benches and only then because I had heard that glue did not adhere to Ipe well even if one cleaned the surfaces.

If found that a Domino joint is almost impossible to disassemble after just a few minutes of clamp time. I use Titebond III. I still leave the clamps on for 20 minutes, but 5 is probably enough if the pieces fit together well.