Thread: DIY Furniture: Dowelmax or Festool Domino?

Of course I have seen failed dowel joints, but bear in mind that "there are many more chairs out there with doweled joinery versus regular mortise and tenon joinery" (to quote another poster), so you are going to see more failed dowel joins just through the law of averages.

That is supposition. Do you pull apart every chair you see to discover how it is joined?

The evidence, for me at least, is clear that dowels fail at least as often as other types of joints. They are associated with cheap furniture, and yes there is plenty of it. However, it does not logically follow that because you see more of it, that the failures are in proportion with other joint types.

My parents have a pine dining setting that was built for my Grandfather about 60 years ago. It was put together with dowels. Not one of those chairs is without a loose joint. In fact I think it is only friction that is holding them together. That's the thing about dowels - they will hold after the glue has failed but the joint will be loose. A biscuit will fail immediately the glue lets go. I simply cannot think of an instance where I have found a mortice and tenon joint that has been subjected to normal wear and tear that has come apart. I'm sure it happens but I haven't seen it. The other thing about a mortice and tenon is that it can be pegged. You can't do that with a dowel. So you are 100% reliant on the glue.

So I'm not saying that a mortice and tenon is some kind of super joint (that would be the dovetail). But I cannot accept that a dowelled joint is stronger.

SilentC, regarding your Grandpa's 1940s dining set with loose dowel joins:

• the glues back then were often rubbish
• the dowels were not compressed
• dowel holes were then (and to some extent are now) often drilled with an approximately right sized drill bit. Result is loose joins. Dowelmax overcomes this.
• maybe your grandfather was a lousy carpenter? (just kidding)

He didn't make it

Yes these things are all true. I'm not saying that the Dowelmax is not a wonderful device for inserting dowels. I'm just saying that dowels have their weaknesses and I take the test results published on that site with a grain of salt. I also can't imagine using dowels in any of the furniture I make, but that is probably the result of my prejudice concerning them. I don't associate dowels with 'fine' woodworking.

This concept of compressed dowels is new to me though. So this means you need to use a special type of dowel in order to achieve the joint strength they claim. Doesn't that mean that it is more about the type of dowel than the jig, and that any dowel joint can be improved using this type of dowel, regardless of whether you use the Dowelmax or an old Stanley dowelling jig?

Are you also familiar with the Beadlock system? What do you make of that? It seems to be a combination of the dowel jig and floating tenon principles.

Originally Posted by silentC

This concept of compressed dowels is new to me though.

I seen a sideboard a few months ago that was put together using compressed dowels. Their were "dips" where all the dowels were placed. They swell on assembly and when the top was sanded excess timber was removed, and over a period when everything ballanced out and returned to normal the hollows/dips appeared. Needless to say the maker wont be using them for panel work again, he is going back to biscuits.

Lignum, that's news to me. I'll investigate.

Meanwhile, some guy in Canada who has a Dowelmax and Domino did some strength tests. His results were:

Biscuit 250lbs
Pocket Holes 420lbs
Traditional tenon 480lbs
Domino 540lbs
Leigh FMT 680lbs
Dowel 890lbs

From forum.canadianwoodworking.com/showthread.php?t=18692

Hmmm, so he's done one example of each joint and based it all on that.

I must say, his M&T looks a bit rough. Not surprised it failed. When he says they failed in the joint, is he saying that the joint pulled apart, or did it snap? How long did he let the glue cure before testing? Maybe there is higher friction in these compressed dowel joints that resists being pulled apart while the glue is still fresh. Maybe he should make some more and test in a month or two.

Not scientific enough by half I reckon. At the end of the day, all it proves is that all joints ultimately fail if you put enough pressure on them. What I want to know is how your dowel joints will be in a few decades.

Originally Posted by silentC

Hmmm, so he's done one example of each joint and based it all on that.

Oh FFS, is there no satisfying you? His results confirm the Dowelmax tests, the ones you said were untrustworthy.

I must say, his M&T looks a bit rough. Not surprised it failed.

Come on, do you really think doing one of each joint and then testing it to failure proves anything? You need to do several, and in different types of wood. That test is meaningless. Wish I could find the one I saw a few years ago. At least they tested about 10 examples of each joint type.

Thanks for the little representation of your favourite pastime there at the bottom of the post. But it's more than we needed to know, really.

Here you go. I did a little search myself and found this in the first page of results:

http://books.google.com/books?id=GGG...sult#PPA162,M1

If you look, you can find references to support any claim you want to make.

I contend that the evidence is out there in all the creaking, groaning dowelled furniture. All you have is a test conducted by an amateur and a test conducted by a manufacturer of dowelling jigs.

SilentC, you are looking in a 30yr old book edited by a guy who got his degree in ~1945. This pre-dates a lot of what we are talking about. In that book and in those times, a Dowelmax joint did not exist, and instead 2 dowels joints were usual (any more and you ran the serious risk of a line-up mismatch, now obviated by the Dowelmax). Here's how they saw joints back then (from a same vintage book):

Well, interestingly, wooden furniture has been around a lot longer than that. Most of the furniture that is sought after is at least that old. They must have known something.

My point, as I said, is that you can find references to support whatever claim you want to make, but the evidence is there for all to see. Unless you want to tell me that there is something special about the dowels that are used. But then that would cancel out your argument concerning the special Domino tenons.

US- Oz how long have you worked for dowelmax

Lignum, I'm going to ask them for a retainer.

SilentC, the quote about dowel joint strength you referenced is actually from this paper: Sparkes, A.J. 1968. The strength of mortise and tenon joints. Furniture Industry Res. Assoc., Maxwell Road Stevenage Hertfordshire, Great Britain. Things have moved on since then, specifically:

- multiple dowel joints made easy by Dowelmax
- far better adhesives