dowels

[Cooler]

I have recently renewed my interest in dowels.  For a long time I was under the impression that dowels were stronger than biscuits, but not a good as almost any other type of joint.

But recent online research revealed that the RTA (ready to assemble) manufacturers' association and the flat pack cabinet manufacturers association in Europe have commissioned studies on the strength of fasteners as relates to their industry (which is mostly assembling sheet good into some sort of rectangle).

Their tests basically have a  piece of flat goods (18mm plywood, MDF or particle board) attached in a T-form and then they add weight the the "shelf" that is supported by one side only.    The tests do not include glue, they are measuring the mechanical strength only.

Particle board is by far the weakest.  Followed by MDF and then plywood.  That did not surprise me.

Wood screws (conventional) were the weakest.  Next cam Confirmat screws which were about 40% stronger than screws.  Apparently they behave like steel dowels as well as screws.  But the high scoring was done by the dowels.  For racking strength they were easily the strongest.  Surprising to me was the dado.  The mechanical strength of a dado was too small to measure.  

Of course glue changes everything, but dowels will almost certainly be stronger in a glued up test also.

Having said that I am not giving up dadoes, but I am going to use Confirmat screws.  

But there are places where visible screws are not acceptable.  Then dowels make sense.  

Has anyone seen or used the Mafell dual dowel system?  It is ungodly expensive but it looks very efficient.

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[Stwood_]

Hmmm, interesting. The Mafell dual dowel system.

[giradman]

Hmmm, interesting. The Mafell dual dowel system.

Thanks Cooler for bringing up this topic - as to joinery these days, I use either free tenons (mortise both pieces w/ a router jig) or dowels (have a number of different jigs) - I'm a BIG fan of dowels, so making the holes in a different way is of great interest.  However, the cost of the Mafell Duo Dowel machines are difficult to justify for my 'amateur' use, i.e. $1200+ in first pic below - while exploring this product, a Triton machine for $180+ on ToolNut was also found - NOW - I could buy that machine if the accuracy & setup were decent - I'm sure that the Mafell is like the Lamello amongst biscuit joiners.

SO, does anyone have experience w/ the Triton Duo Dowel machine OR are there other brands that will make a double dowel hole?  Thanks for any comments - Dave

[jteneyck]

Those Euro cabinets are put together with a LOT of dowels, essentially one every inch or so. The only way to do that efficiently is with a line boring machine.  If you want to spend obscene money on a joint machine then I would buy a Domino; it's about the same price as that double dowel machine, and a lot more versatile.

You seem to be attracted to expensive tools of questionable utility lately.  Did you win the lottery? 

John

[giradman]

Those Euro cabinets are put together with a LOT of dowels, essentially one every inch or so. The only way to do that efficiently is with a line boring machine.  If you want to spend obscene money on a joint machine then I would buy a Domino; it's about the same price as that double dowel machine, and a lot more versatile.

You seem to be attracted to expensive tools of questionable utility lately.  Did you win the lottery? 

John

Hi John - not sure who you're referring to above since there are a number of previous posts - love this European technology but have just a handful of Festools - I'd love a Lamello biscuit joiner, a Festool Domino, and now a Mafell Duo Doweller, but would certainly not be willing to pay the price for these machines, unless I was a professional who would be using these tools on a daily basis.

BUT, the Triton Doweller interested me for the price - however, the reviews that I've read are quite mixed w/ a lot of negative comments on accuracy - below is a video that sways me against buying this less expensive alternative to the Mafell machine.  Hopefully, others who may own or have compared these dowelling machines will post?  Dave

[giradman]

For those interested in the Triton Duo Dowelling machine, several follow-up videos are available - Dave

[bhh]

Dowels?  Meh.  Most tests are done after the glue cures, not 3 or 4 seasonal variations later.

http://www.finewoodworking.com/1980/04/0...owel-joint

[jteneyck]

Hi John - not sure who you're referring to above since there are a number of previous posts - 

Oh, sorry.  To the OP.
John

[giradman]

Dowels?  Meh.  Most tests are done after the glue cures, not 3 or 4 seasonal variations later.

http://www.finewoodworking.com/1980/04/0...owel-joint

Well, that is nearly a 40 y/o article by R. Bruce Holdley (own several of his excellent books) - unfortunately only a synopsis is given and the complete article seems unavailable w/o a payment fee - now there are many other articles comparing tenon & dowel joints - e.g. an interesting read is HERE - I would have liked to have seen the use of just two 1/4" dowels, but the bottom line is that dowels and tenons have excellent and similar strength - preference is more likely related to a personal choice, techniques used, and jigs/tools available - nice to have both options.  Dave

[Cooler]

There is a video comparing the Triton to the Mafell. Watching the video killed the Triton for me. It is a You Tube video and easy to find.

There is just one greedy distributor for all of North America. I thought of bringing one in from England, but when I saw it was 220 volt. So no go.