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Post by lynx on Nov 2, 2008 19:20:19 GMT
Whilst enjoying Sunday lunch i had a quick browse of the festool brochure. I noticed the domino used for the M&T joint for a window frame. Basically, butt joints on the jambs, scribed to the shape of the head and cill and then jointed using the domino.
I think the idea is the same as the traditional M&T joint but I can't get it out of my head that it's not as good in strength terms. But then I feel it maybe as strong, just can't put my finger on it.
What are peoples views on this joint in this situation? Has anyone made a batch of window frames using the domino?
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Post by jfc on Nov 2, 2008 19:49:32 GMT
;D
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Post by lynx on Nov 2, 2008 19:51:53 GMT
?
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Post by jfc on Nov 2, 2008 19:55:50 GMT
I just found using the domino for external joinery very funny . I think the stated when they first started selling them that they are not for external joinery . Now they are ? ;D
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Post by lynx on Nov 2, 2008 19:58:16 GMT
That's what i feel, not suitable. But why not?
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Post by jfc on Nov 2, 2008 20:11:03 GMT
Theres a thread on here somewhere with every single reason why not .
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Post by sainty on Nov 2, 2008 20:40:12 GMT
Heres some Festool bumf that suggests that it would be possible www.festool.co.uk/images/gb_downloads/brochure_domino_accessories.pdfTheres a photo showing a window! External Dominos too! I think it would depend on how many dominos you use. The thing is you are always relying on the glue, but traditionally you could rely on wedged M&T if the glue fais. So I guess he question is how good are modern glues? rgds Stu |
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Post by jfc on Nov 2, 2008 21:06:23 GMT
I will let you know in a hundred years ;D I think the main problem is the tool makers are treating external joinery like internal carpentry . You can knock a wardrobe together with any method and it will last as long as the householder is there or fashions change and they want something else . External joinery should be made to last and by not making it to last you could be introducing problems to the rest of the building . Rot being one of them .
I bet those external dominos are Luan or Meranti / Paint grade hardwoods .
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Post by engineerone on Nov 2, 2008 21:20:31 GMT
surely the whole point of a proper window design is that at the joints it is aimed at removing the water from them. with a domino, you would i guess need a flat plate where they intersect, and thus could well get a water flat spot where it would pool and eventually cause leakage. paul  |
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Post by sainty on Nov 2, 2008 21:39:31 GMT
I don't think that you need to change the design of the window to accomodate the domino Paul, so in that respect a dominoed window should be no different to a traditional one. In fact with no through tenon, there is no end grain to worry about on the tenon, which actually is an improvement over traditional construction in that respect.
rgds
Stu
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Post by jfc on Nov 2, 2008 22:08:06 GMT
How do you wedge a domino then , a tenon is a naff joint without its wedges . With the wedges it is the king of joints tried and tested over billions of years .
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Post by lynx on Nov 2, 2008 22:10:41 GMT
do you wedge the frame then? Even on some of your jobs it's been M&T, Glue and screw
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Post by sainty on Nov 2, 2008 22:20:52 GMT
No, no, no, I said that there is no end grain showing on the domino which is an improvement over the endgrain showing on a through M&T. I've already highlighted the fact that dominos are reliant on the glue because there are no wedges to act as security for the glue failing.  Billions of years  rgds Stu ;D |
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Post by jfc on Nov 2, 2008 22:32:02 GMT
Thats a bridle joint not a mortice and tenon , again crap joint but better than any other joint that will do the job . Backed up by any mid rails or mullions / muntins / what ever you all call them now ;D That are through wedged mortice and tenons . That baby aint going anywhere . Domino Joinery is for internal second fix work and IMHO has no place in external joinery . Maybe an internal door but hmmmmmmmm .
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Post by Keith on Nov 3, 2008 8:17:56 GMT
So I guess he question is how good are modern glues? Last year I started a glue trial for The Woodworker magazine. I made lap joints in oak and in softwood with all the glues I was testing at the time and they have been left outside since then. I have just had the first failure, which has come as a surprise to me as it is the softwood joint I made with Polymite (the old cascamite) that has failed. I expected the PVA glues to fail first  . That said window joints don't take much if any stress, I've just replaced some frames which were just butt joints with a single screw. They have lasted over 10 years and are still perfect; well as good as the day they were made anyway ;D |
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