Domino 500 advise

[custard]

The points are worth mentioning in a domino thread IMO as, if you have one, you don't really need a biscuit jointer as it does all that and much more besides.

I disagree. I use both a Domino and a biscuit jointer, they're different tools and both have advantages and disadvantages.

How so? I could only see using biscuits for alignment which dominos do as well and fit in tighter spaces (4mm ones for example). I don't doubt you have very good reasons... I'm just curious.

These are rubbish photos but they'll do to illustrate the point,

The construction of this desk is basically saw cut veneers on a ply or MDF ground. There are two drawer dividers running from the front to the back between the three drawers, and these dividers need jointing to both the top and the bottom of the desk. Biscuits are a better choice for this job than Dominos. The reason is the fit of the drawers is very precise (with little details like Rosewood runner strips let in to the base below each drawer side to facilitate a super smooth action), but Dominos risk causing a minute local swelling in the drawer dividers that could make the drawer bind. You can check this for yourself, pop a 6mm or 8mm Domino into the edge of some 15mm or 18mm MDF and then measure the thickness of the MDF in the vicinity of the tenon, and again a little distance away. You'll find there's every chance the MDF is a whisker thicker where the Domino has distorted it. The problem is Domino tenons have a tolerance in their dimensions, and at the thicker end of that tolerance range they're capable of pushing out and making MDF (or indeed ply or solid timber) bulge very slightly. You may well have had the experience on a test assembly of some Dominos that slot in relatively easily while others are very tight. In most cases this isn't a problem, but with the much tighter tolerances needed for top quality veneered work it can be an issue.

This is just one example, I'm sure if I reflected on other furniture builds I'd find more. I'm not anti Domino in any way, I have the 500 and 700 and use them both regularly, but they are a long way from being a silver bullet solution for all a furniture maker's jointing requirements.

 

[Nelsun]

Fair do's Custard. Thanks for the enlightenment. I'd read (somewhere on the internet so pinch of salt) about biscuits "rising" I think they called it when they are close to a face edge. Swelling due to glue reaction IIRC. But I'm guessing that's either myth or down to glue choice? No matter... for my level of wood butchery I should be fine enough

 

[RobinBHM]

Fair do's Custard. Thanks for the enlightenment. I'd read (somewhere on the internet so pinch of salt) about biscuits "rising" I think they called it when they are close to a face edge. Swelling due to glue reaction IIRC. But I'm guessing that's either myth or down to glue choice? No matter... for my level of wood butchery I should be fine enough

Its true, it is possible that biscuit positions can telegraph through just enough to be seen in some lights even if it csnt be felt.

Not generally much of an issue mostly unless on thin materials with high gloss finishes.

On veneered boards the veneer stitching can telegraph through and is a much worse problem.

 

[memzey]

I think that happens with biscuits if you sand or plane the wood down before the glue has dried properly. If you leave enough time between glueing up and sanding you should be alright.

 

[MikeJhn]

Surely whether domino or biscuit, if its close to the surface when either expand they will cause a bump?

Biscuits will expand when glued, they are designed that way, they will also swell if left outside their plastic bag, easy remedy is to put them in the microwave for 30 seconds or so, I imagine this will also address any issues with loose tenon domino's that have swelled.

Mike