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Wood Rectangle Flooring Hardwood Composite material


Table Wood Rectangle Flooring Floor


Table Wood Rectangle Flooring Floor


I am making a table from 7/8" thick spalted maple with a border of 1 3/8" rustic maple. The rustic maple is used to make the top appear thicker. I planned to put breadboard ends on the tabletop, but have an issue.
The table is supposed to be 60" long and I planned to have two 6" wide breadboard ends to make the table complete. The spalted maple is already cut 48" long and the two breadboard ends are 6" each, giving me the 60" needed.
Unfortunately I didn't take into account the loss of the spalted length when I make the tenon. If I use 2" tenons on each end my table will shrink by 4" and I'll have a 56" long table. The breadboards are already cut too.
Of course I can make new ends that compensate for the loss of the spalted maple tenon length, but that wastes wood and it kills me to have part of the spalted wood hidden inside a breadboard mortise.
What is the minimum length of tenon I can safely use to make the top. The width is 42" total.
Is there any other way to make this top and preserve the maximum spalted material
This is a gift so the quality of construction is the most important.
See photos for an idea of what I am dealing with. The breadboard is just sitting next to the top for the photo.
Thanks for your input!
John
 

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Rather than cutting a tenon on the end of the top, how about cutting a slot and installing a spline (or a series of slots and splines? Sort of like biscuit joinery, but deeper grooves and wider splines for more strength and ability to keep the top flat. I would orient the grain of the spline to match that of the table top to minimize any potential problems with wood movement. Actually, if you could use some of the spalled maple you shouldn't have any issues.

Must be a winner of an idea, since two others posted comparable solutions while I was (slowly) typing!
 

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I think floating tenons are your way out here. Something like 4" tenons with a spline in between would essentially create the same structure as a traditional BB end without losing length.
 

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A breadboard end is a cap to prevent the rapid exchange of moisture through end grain. Unless it's relatively massive and on a proportionally short table, it has very little if any mechanical restriction of cupping. So the tenons must be long enough to have a little meat on the outside of the dowels, but that's all they need.

But, if you think about the mechanics of it, you don't want extremely wide breadboard ends hanging off of short thin tenons, because you'll have too much leverage at the end and run the danger of snapping the tenons off, or leveraging the ends off of their tenons.

Floating tenons are a great solution- glued into the top, and of course pegged, not glued, into the breadboard.

I don't see how dominos have enough room, that is, they're not wide enough, to allow for the elongated dowel/peg hole to be wide enough. IMO, something like, say, five or six tenons roughly the size and proportion of a poker deck (but thinner vertically, of course, considering the thinness of your top) would be best. A board of maple that wide is going to move so you need room to elongated your dowel holes.
 

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Discussion Starter · #8 ·
OK guys it appears that a floating tenon may be my salvation. Thanks for your ideas
Questions:
1. How deep into the spalted maple top do you make the slot?
2. assuming I use a "biscuit" cut from the same maple and oriented the same direction I assume that I would glue in these "biscuits. Correct?
3. How deep in the breadboard do I cut the slot?
4. I assume that I only glue just the center biscuit in the breadboard and pin the rest with elongated holes just as if I was doing a solid mortised and tenon. Correct?
5. Considering the spalted maple top is 7/8" thick, what thickness would you make the slots and biscuits?
Thanks again guys!
John
 

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Discussion Starter · #10 ·
Thanks Guys, I understand what your saying about the need for material. I don't have a domino machine and unless I win the lottery I won't have one to do this job.
I am concerned about only having 7/8" material thickness. If I cut a 1/4" slot that leaves me only 5/16"" thickness of table top supporting the biscuit. Is that ok?
In order to get a deep hole I see buying a up- cutting spiral bit of 1/4" diameter. This bit Freud 75-102 will cut 1" deep. Is this deep enough or should I chisel deeper and if do how much deeper. (don't have a mortise machine either dang it!
Thanks,
John
 

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OK guys it appears that a floating tenon may be my salvation. Thanks for your ideas
Questions:
1. How deep into the spalted maple top do you make the slot?
2. assuming I use a "biscuit" cut from the same maple and oriented the same direction I assume that I would glue in these "biscuits. Correct?
3. How deep in the breadboard do I cut the slot?
4. I assume that I only glue just the center biscuit in the breadboard and pin the rest with elongated holes just as if I was doing a solid mortised and tenon. Correct?
5. Considering the spalted maple top is 7/8" thick, what thickness would you make the slots and biscuits?
Thanks again guys!
John

- Michigander
Maybe Steve Rowes' excellent tutorial may shed some light:
http://festoolownersgroup.com/festool-how-to/making-a-breadboard-end-with-the-domino/msg365913/?topicseen#msg365913
 

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Didn't realize the domino had different widths, waho609, that's cool.

Personally I'd want the tenons good and wide- if you look at a traditional breadboard end, it's kind of a toss up as to whether you might call it a row of tenons, or one long tongue with gaps in it.

Michigander, the rule of thumb is thirds, but I think you want to favor the thickness of the tenon a bit here, so, 5/16". Because it will be glued into the top, you're basically recreating solid wood, so the tenons will be plenty strong.

And say 2 1/2" inches into either side, for a 5 inch tenon, oriented as you describe. That would be overkill on edge to edge floating tenons, but the glue in that case is stronger than the wood, whereas here you need a mechanical attachment. The elongated holes, in all the tenons except the center one, as you describe, should allow easily half an inch on either side of the dowel. 19th century stuff I've taken apart in salvage allows for about an inch per foot of width ( +/- 1/2" either way), kind of hard to argue with stuff that's still in perfect shape 130 years later.

Oh- Kazooman's idea of a short-grain spline between the tenons is great because of aesthetic considertions (decades later you might get a visual gap between the top and end). These wouldn't have to be more than 1/2" into both top and end, and of course like the tenons, glued into the top and not into the end.

Basically you're recreating the tenon/tongue part of a traditional breadboard end, with floating elements. It'll be great.
 

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Great point bobro. The Domino has several settings for width

and different settings for depth, if I understand you correctly.

- waho6o9
Yes, the Domino can cut a wide slot, but how do you cut a-say 1" wide-slotted hole for a dowel into the Domino without cutting the Domino in two?

I would use something like a 3" wide tenon-2" at a minimum
 

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Discussion Starter · #14 ·
Thanks Bobro for the detailed explanation!
If as you say I need a 5" total tenon, that means I need to cut a 2-1/2" deep groove to accept the floating tenon. Without a mortise machine how would I cut such a deep slot. I see Sorby makes 5/16" wide mortise chisel. I have a 1/4" chisel. Is that thick enough or should I buy the Sorby?
It looks like I have a lot of chopping ahead of me. Did I mention there are 2 benches that also need breadboards? ;~)
Thanks,
John
 

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Michigander, others may disagree but I prefer a chisel narrower than the mortise. It might take a touch longer but I never have to resort to such shenanigans as clamping blocks about the edges for vertical reference, so, heh.

If you look at the profile of a typical breadboard end, it looks like a tongue and groove. You might call this an "open" breadboard. But if you think about what you're doing here, recreating the tenons/tongue with floating tenons, you'll see that you can't do this without looking like crap. So you need a "closed" breadboard end.

Had a little downtime in the shop this morning so instead of bopping over to the neighboring bar for a quick beer, I sawed and chopped out the tenons/tongue of a "closed" breadboard end on a cherry board.

Image and video hosting by TinyPic

So you can see the basic proportions of the thing. The mortises on the end piece need to be wider than each extended tenon; I'll go something like 1/4" on either side of the tenon on this one (the board is only about 11" wide).

Your work is harder because of the mortises. Because you're gluing grain to grain with the same kind of wood in the top, you could go with 2" into the top and 2 1/2" into the end, IMO. It's not hard, just take your time.

Oh- learned the hard way. If you're chopping a mortise into the end grain of a thin board, sandwich the thing between some pine boards, because the mechanical advantage (leverage) you get with a chisel is a lot more than might appear, and it's easy to crack the board on either side of the mortise. Until the tenon goes in, then the thing as a whole is extremely stong.
 

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Discussion Starter · #17 ·
Bobro, you are the man! Thanks so much for taking your time to not only address my questions but to build a mock up of my project is over the top. This helps immensely. I have never chopped a mortise before and my 1/4" mortise chisel is so far unused, but you give me confidence to get in the basement and start practicing. I understand your point about closed breadboards. That will make the breadboard look good from the side. When you made the long mortise in the end grain did you chop all of it or did you use a router?
Enough questions for now, I'll get in my shop and see what happens!
I'll report later.
Bobro, you are a great example of the reason I so much enjoy this website! Thanks again for your help!
Best Regards,
John
 

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Wood Natural material Table Floor Wood stain


Well Bobro, I practiced making mortises on some scrap cherry which worked out OK. However when I used spalted maple cutoff from the table top I found the material cracked very easily even though I used back up boards to support the walls. I even chiseled a border to start the mortise using a regular chisel, like how you define a dovetail. I've come to the conclusion I can't make a mortise in the spalted maple. It has hard and soft spots and I'm concerned about the overall durability of the table. So I am resigned to making a traditional tenon on the end of the spalted maple and giving up the length and making the breadboard longer so that I keep the 60" length. Using a traditional tenon, do you think I can safely use a 2" tenon length instead of a 2-1/2" like bobro you suggested? Here is a picture showing the breakout.
Sorry for being such a pain on this project. I've learned there is a reason folks don't use spalted maple for large projects.
One last question, I've heard that spalted maple can be "stabilized" using a "CR" glue. Does it make sense to do this to the tenons to strengthen them? Do you just brush CR glue on the wood surfaces?
Thanks for your input guys!
John
 

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If you are having that much trouble with cutting the mortise, it doesn't bode well for the strength of the tenons if you cut them on the end of the top.

It occurred to me that your spalted maple is 7/8 and you are wrapping the entire perimeter with 1 3/8 maple. One way to provide extra strength and to attach the end pieces might be from the underside. You could make a 1/2" deep rabbit (or several) in the stock for the end piece and use 1/2" stock to join it to the table top. You would need to employ the usual precautions about cross grain situations and wood expansion, just as in the case for the tenons. Not a traditional way to join the pieces, but it could work and would not show.

Don't give up on keeping the full length of your spalted maple just yet. I am certain that someone will.come up with a solution.
 
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