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Post by mrgrimsdale on Jan 19, 2009 19:34:41 GMT
Anybody got any useful bread board end technique suggestions? I'm looking at the Thos Moser book which looks OK but I wonder about the outer pegs in sliding slots; I see them sticking, or if they don't they are perhaps redundant. Just a central fixing instead, 2 pegs about 6" apart?  PS found it. loadsa good stuff on the net, this just one: www.beautifulwood.net/html/breadboard_ends.html |
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Post by nickw on Jan 20, 2009 9:08:19 GMT
I've used the elongated hole technique. The main top expands and contracts quite happily relative to the end cap- no sign of sticking. The peg is there to stop a gap opening up 'twixt the end cap and the main body of the table, so is not redundant.
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Post by mrgrimsdale on Jan 20, 2009 14:10:19 GMT
I've used the elongated hole technique. The main top expands and contracts quite happily relative to the end cap- no sign of sticking. The peg is there to stop a gap opening up 'twixt the end cap and the main body of the table, so is not redundant. Righto ta. I've been reading up - high levels of complexity are possible! One option is elongated holes which are slightly oval, rather than straight sided. This makes the BBend pull in tighter if there is any movement; a sort of horizontal draw boring. Don't think I'll do that one - or the dovetail housing option which looks attractive but structurally flawed IMHO. But I will go for the 3 tenons and through stub-tenon option I think. WIP snaps soon! |
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Post by andy king on Jan 20, 2009 17:09:53 GMT
talk me through how you make a 'through stub-tenon'. A through tenon is a through tenon, a stub tenon is a stub tenon surely?
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Post by roines on Jan 20, 2009 17:33:32 GMT
unless its a half lapped stubby through tennon with a twist on the end (top side obviously)
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Post by mrgrimsdale on Jan 20, 2009 17:50:00 GMT
talk me through how you make a 'through stub-tenon'. A through tenon is a through tenon, a stub tenon is a stub tenon surely? I meant 'through' from side to side i.e. the whole width of the table top. Some are stopped short of the ends, on some of the pages I've looked at. Obvious, I thought. ;D |
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Post by andy king on Jan 20, 2009 20:35:41 GMT
Nah, not really.
What you are describing is a shouldered tenon, completely different and bad terminology.
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Post by mrgrimsdale on Jan 20, 2009 20:54:26 GMT
What I was trying to describe was the tenons + haunch or stub whatever you call it as shown here by Chris SchwarzNot a 'shouldered' tenon? As I understand it a shouldered tenon has shoulders at different positions e.g. as you might find if you put a rail into a stile with a rebate including the mortice. I've changed my mind about taking the haunch/stub/thingy 'through' but will stop at the end of the outer tenons, so it won't be seen from the side. The reason why I'm looking closely at this is because the table top I last did with bread board ends didn't work - I didn't know about the sliding glue free joint and took a chance.  |
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Post by andy king on Jan 20, 2009 21:01:27 GMT
That picture you linked to is certainly a haunched tenon.
A shouldered tenon is one where the tenon sits in from the outer edges of the stock so the mortice edges are completely hidden by the shoulder overlaps once assembled and gives a neater finish to the work.
Often common practice in better quality jobs, both joinery and furniture.
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Post by andy king on Jan 20, 2009 21:05:18 GMT
When I was at college that was called a step shouldered tenon.
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Post by mrgrimsdale on Jan 20, 2009 21:10:51 GMT
That picture you linked to is certainly a haunched tenon. A shouldered tenon is one where the tenon sits in from the outer edges of the stock so the mortice edges are completely hidden by the shoulder overlaps once assembled and gives a neater finish to the work. Often common practice in better quality jobs, both joinery and furniture. That's what I'd call a four shouldered tenon, as distinct from a common tenon which has two shoulders, or a fair faced tenon with one shoulder. Or is it flush tenon? PS Yes 'stepped' tenon makes sense. So if I don't take the haunch through it becomes a shouldered tenon by your definition. |
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Post by andy king on Jan 20, 2009 21:18:02 GMT
Four shouldered is traditionally known as a shouldered tenon.
Two shouldered tenons often referred to as straight tenons.
Don't know about the terminology taught in the colleges up there, but down here that's known as a bare faced tenon.
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dunbarhamlin
Full Member
Lutherie with Luddite Tendancies
Posts: 244
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Post by dunbarhamlin on Jan 20, 2009 21:29:51 GMT
Coming in, you'd think something tradition bound like carpentry would have a pretty consistent base of jargon, but one thing I find is that every generation seems to redefine the terminology.
I find it confusing at times, moving between writers of different ages.
Expect part of it is a melding of traditions from different specialties, guilds and regions.
Even perplexing when just talking saw teeth. The definition of fleam seems to depend on the day of the month.
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Post by 9fingers on Jan 20, 2009 21:48:35 GMT
I must admit to being confused by breadboard ends. yes I understand the expansion is accommodated but surely whenever the moisture content of the wood is different from the time of manufacture, there will be a lip at the end of the BB ends. TO my mind all it offers is to share the expansion or contraction between the two ends of each edge and reduce the risk of splitting that would otherwise occur with rigid gluing of cross grain edge.
It is still going to look bad to me.
Or have i misunderstood??
Bob
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Post by engineerone on Jan 20, 2009 22:01:24 GMT
i think the idea about bread board ends is to reduce the chances of too much moisture going into end grain. in most cases bread board ends are used on tables, or blocks that are going to be washed, ie breadboards but certainly i have never seen an old item with these ends that has them constantly in line during the entire season of a year. the only way it really becomes effective is when used in conjunction with veneered mdf ;D paul  |
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Post by mrgrimsdale on Jan 20, 2009 22:14:45 GMT
I must admit to being confused by breadboard ends. yes I understand the expansion is accommodated but surely whenever the moisture content of the wood is different from the time of manufacture, there will be a lip at the end of the BB ends. TO my mind all it offers is to share the expansion or contraction between the two ends of each edge and reduce the risk of splitting that would otherwise occur with rigid gluing of cross grain edge. It is still going to look bad to me. Or have i misunderstood?? Bob The idea is to make a neat end to a joined board table top and to stop it from warping. An exposed joined board top end tends to split as it is drying or absorbing moisture sooner than the middle of the table - causing differential expansion. The BB end will slow this down but won't entirely stop movement, which will be greater across the table top than along the BB end - so some allowance has to be made for this by having it fixed only at the centre. So yes you will get a seasonal difference at the BBend where the expansion or shrinkage will show - but hopefully no one will take much notice! If you fix a BB end tight you will get splits in the top as it shrinks inwards but is held at the ends - as I found out with my first experiment. |
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Post by paulchapman on Jan 20, 2009 23:08:00 GMT
The idea is to make a neat end to a joined board table top and to stop it from warping. I'm not convinced that breadboard ends will do much to stop a table top from warping. If the wood's going to move, it's going to move. I think you'd be better off making sure the wood is sufficiently dry before you make the piece. Cheers Paul |
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