Jointing or Biscuits

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Hi all. For my exterior door frame project.... I will be butting together two lengths of sapele/mahog. The individual pieces are about 22mm x 140mm and 1040cm long...and joining them on the long edges to make 260mm wide panels. Should I buy a jointing router bit or can I get away with using biscuits. Once they are joined i will be fielding them.
Thanks.
Arthur
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Arthur2 wrote:

You don't need either...just glue should be fine. You can certainly use biscuits for alignment, but they don't help at all as far as strength of the joint.
Chris
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True enough.

NOT true at all. This seems to be a widely quoted myth parroted around here amongst the literati.
One minute of research will get EMPIRICAL research to show differently. You can get started here:
http://tinyurl.com/6qjcu9
But please don't stop there. There is a lot of easily obtained information about the strength of a biscuit joint when >>properly executed for the right type of joining<<.
Note that method, project design and understanding of the joints made by this machine are important when maximizing the use of it, just as it is with any other machine.
I think this stuff started when couple of these limp assed woodworking for idiots magazines (including an op-ed piece by Rockler that compared it to the Dowel Max) tested the biscuit joiner to see if it was the do all, end all device for every single application. Obviously it is not, nor is any other joining machine.
But to dismiss it out of hand as being useless is absurd.
Robert
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biscuits, not three. pieces were 2X4, about 15' long. Set 48 hours with Titebone #2. I was surprised how easily they (biscuits) broke, 1/2 in each piece of 2x4. Did not use a scale to measure force. Nothing failed but the biscuits. I asked the question about the difference between Lamello and PC here about a year ago. That was not answered, but got all kinds of reasons it failed. None applicable. After that, biscuits were for alignment, the added strength was secondary. I still would like to know if there is a diff between Lamello and PC biscuits.
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On Thu, 7 Aug 2008 09:02:26 +0300, "Rick Samuel"

I am not sure how your test disproved the data when your test was not the same (2 vs three busuits) and you did not do a comparison with a non-biscuit joint to compare amount of pressure required to break the joint.
Of course none of that would change the fact that you were surprised at how easy the joint broke, but just pointing out that it was not "the same" test and not neccesarily conclusive. -Chef Juke "EVERYbody Eats when they come to MY house!" http://www.chefjuke.com
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Chef Juke wrote:

Besides that with a 15-foot moment arm he could have broken _any_ rigid joint between 2 2x4s joined 90 degrees without much effort.
The biscuits broke, he said. If it had been a mortise and tenon the tenon would have broken. "Stronger than a butt joint" doesn't mean "infinitely strong".

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True, my test was NOT controlled, but a M&T joint would not be broken by hand. The parts were 15 inches, my error. The first initial movement of the joint is to pull the fibers apart, not to bend them. Tyr pulling a 1/8 dowel apart.
I don't see an answer to difference between Lamello and PC biscuits.
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snipped-for-privacy@aol.com skreiv:

Do you realise that there is a difference between gluing end grain to side grain and gluing side grain to side grain?
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After many years of doing this for a living, yes. Check out the link, do some quick research.
Robert
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Absolutely agree! ... to suggest that properly applied biscuit joinery adds no strength whatsoever to the joint under question defies reason, logic, personal practical experience, and more than one published testing.
There seems to be a proliferation of journalist woodworkers spouting these "truisms" that are more former than latter.
I'll say it again: You gotta love the "wired world" ... the more "facts" available from which to draw wrong conclusions, the more wrong conclusions there are available as "facts".
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Swingman wrote:

Huh? The original poster is edge-gluing long grain to long grain to make a panel. The glue alone is at least as strong as the wood. How would biscuits possibly make the joint any stronger?
Chris
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Agreed, biscuits add considerable strength to butt joints, and miter joints. Today Domino's work even better. ;~)
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<snip>

Leon, it's less expensive to have YOU do the joints, and pay labor and shipping, then buy a Domino.. Yeah, it's tool envy.. [ sigh ]
mac
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;~), boy that Domino saved me lot's of time on my last job. I think I put in about 28 loose tennons on just the legs on the walnut desk. Throw in probably 54 for the top and shelves for aligning the pieces of wood and another 28 for the shelf skirts. Biscuits would have worked on the top and shelf panels but it would have been over 100 mortises done on the mortiser for the shelf and leg skirts. On this job alone the Domino probably saved me 1 full day of work and that is about 1/3 the cost of the Domino.
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myself that a "loose" tenon is a GOOD thing... I hear that expression and think "chair doctor needed here"..
Then again, I'm a turner and haven't even MET Jack..
mac
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LOL, They tighten up.
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Leon, just out of interest's sake have you tested the strength in a Domino connection by purposely trying to break a stile connection off a rail? I'm wondering what kind of strength is inherent in those Domino biscuits or what kind of resistance was encountered before the stile split off the Domino biscuit?
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"Upscale" wrote

Although the machine itself is a spin-off of the plate joiner design, I would be hard pressed to classsify the Domino "loose tenons" as "biscuits".
Here is the supposed results of a relatively recent (07) "Wood" magazine "joint strength" test of various "loose tenon" methods:
Shear Test
Mortise and tenon 1,017 pounds (461 kg) Dowelmax 609 pounds (276 kg) Beadlock 541 pounds (245 kg) Domino 464 pounds (210 kg) Biscuits 187 pounds (85 kg)
Pull-apart Test
Mortise and tenon 2,525 pounds (1,145 kg) Dowelmax 1,866 pounds (846 kg) Domino 1,486 pounds (674 kg) Beadlock 1,170 pounds (530 kg) Biscuits 766 pounds (347 kg)
That said, while it's interesting, I don't know that I'd trust this particular rag to be the final word on anythng ...
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Gotta go along with that... from what I've seen, they're more like an oval-shaped dowel than a biscuit..
mac
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wrote:

Actually a Domino is flat on both ends and on top and bottom only the side edges are round with a radius half the thickness, so the round edges are perfect half circles.
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