Domino 500 and edge joining long board

[JeffOregon]

I am building a rather large Armoire for my lovely wife. It will consist of three cabinets all designed to be knock down. In joining the long side joints,84 inches, how many dominoes / connectors should I use? I hate to use too many or too few.

 

[ishmerc]

I would use six 10 mm

 

[JeffOregon]

I should say that i will be using a mix of domino and KV. I want to make the whole structure knock down for easier moving. I would be edge joining (12) 3/4” x 84” boards.

 

[RDMuller]

Let me throw a little different thought process  into this discussion.  I recently heard a pretty famous national speaker say that you DO NOT use glue on dowels, domoinos or biscuits when gluing up narrow boards.  The glue goes on the edges of the boards, not on the connectors.  Why???  To avoid telegraphing of the connectors to the surface due to moisture in the glue.  I had this happen and it really doesn't show until final gloss finishes are applied.  NOT A GOOD DAY WHEN THIS HAPPENS.

How many connectors?  Enough to get the boards aligned  to the degree you want.  Forget about strength.  That comes from glue along the edges that were clamped.

Use glue on the connectors on other joints

 

[ChuckM]

  I recently heard a pretty famous national speaker say that you DO NOT use glue on dowels, domoinos or biscuits when gluing up narrow boards.  The glue goes on the edges of the boards, not on the connectors.  Why???  To avoid telegraphing of the connectors to the surface due to moisture in the glue. 

Snip.

That's an interesting suggestion of not putting glue to connectors that serve mostly an alignment purpose.

I have heard of telegraphing, but I have never experienced it, and wonder if telegraphing happens only when too much glue is used AND the connectors are placed too close to the surface (e.g. when thin stick is used). When I use dominoes for edge-joining, my stock is 3/4" or 1", as I never find the need to use anything other glue on 1/2" material.

Has anyone done a study on the subject of telegraphing? Is it the thickness of the stock or type of wood or both that may cause telegraphing?

 

[RussellS]

I wonder with the telegraphing, if you let the glue moisture dry out of the wood, then the telegraphing would disappear.  After using the Dominos, let the raw wood sit and air dry for a week or a month.  Then finish.  No telegraphing?  Now I realize letting wood sit for a week or month to dry right in the middle of a project is not something you want to do.

 

[Svar]

DO NOT use glue on dowels, domoinos or biscuits when gluing up narrow boards. 

You probably mean thin boards. This makes sense when tenon/dowel is close to the surface. Plywood is more prone to bulging than solid wood. However, no way a 5 mm domino will have surface effect when placed in the center of a 20 mm maple board, glue or no glue. Also, one typically would plane/sand the lamination after glue dries.

 

[iekoch@comcast.net]

I have only seen this on biscuits, usually it happens when you sand the joints down before everything is dry. The high concentration of glue/moisture bulges the wood some what. Then when you sand the bulge down and the panels dry there is a recess.  I have never had this happen on dominos.