Using Biscuits In Middle Of Board

[berry]

I watched Nick's demo using biscuits to strengthen a butt joint. It was an interesting demo but I sure wouldn't recommend it to a friend.

In Nov 06 Wood Magazine did a Woodjoint Torture Test. It will come as no surprise that a butt joint is the weakest of all. Adding a #0 biscuit added to pull-apart strength but nothing to shear strength in their test.

I know it depends on what your building, but unless this shelf was going to be more decorative than functional, I think you need to add a dado a mechanical fastener or a more functional joint, like dowels.

I own a biscuit cutter and, as a result of that article, have stopped using biscuits, except to line up boards before joining them together.

This is NOT a criticism of Nick and his excellent demos. I'm sure he was showing the versatility of SS's router system and not advocating for butt joinery.

[charlese]

Gotta somewhat agree with you Berry. With emphasis on "Somewhat". I too dislike biscuits for joints, if the biscuits are relied on for strength.

If the piece Nick showed in the video has that butt jointed piece as a vertical member, then there is a purpose of the biscuits to hold the upright from shifting or twisting in the application. You could do the same thing with mechanical fasteners (nails, screws, angle brackets, etc.), but they might show. If the appearance is a consideration, this is a good joint, provided the two horizontal pieces (on either side of the upright) are sturdy.

I would favor a stopped (blind) groove, but gotta admit the biscuits are a quick and easy solution to the problem.

[paulmcohen]

In short, everything I show in the photos minus the miter gauge. Let me know it it's otherwise.

I'll call the Montgomery County Paramedics and see if they will stand by while I do a demo.

With all good wishes,

I have not opened the Box for the Fence, I will assume it is in there. My Shop is under construction and I got the fence at your last sale.

You are now in Marketing (well Technical Marketing) you should not scare away potential customers of the Ring Master. I hope it isn't more dangerous than a table saw (which I have tremendous respect for), I guess we will be learning together.

[scottss]

I guess I misssed the video. I personally haven't used biscuits in a long time. After Norm of new yankee pointed out that he was seeing a change in the form of the wood at the biscuit spot he quit using them almost totally except for miters. I have built some older projects with the biscuits in them and now for the past say 5 years I haven't used them at all. With todays glues I don't think your going to need them and if the boards are off that much maybe you need to pick different wood. Now and then I think it would be nice to have a biscuit cutter but I have passed. I had a pc and sold it to my brother and he lets me use it if I want. I just don't want to travel a half hour away just for something that I don't really need.

[mlettini]

Incra also has an 18" fence they sell for the original Incra jig which can also be made to fit the miter guage. By the way it also comes with a stop and extender, all for $34.95 purchased directly from Incra.

[Nick]

"In Nov 06 Wood Magazine did a Woodjoint Torture Test. It will come as no surprise that a butt joint is the weakest of all. Adding a #0 biscuit added to pull-apart strength but nothing to shear strength in their test."

The tests in Wood #173 to which you refer measure racking, even though the author continually refers (incorrectly) to shear. I can't help being skeptical of quasi-scientifical tests designed by folks who don't know the definitions of the terms they are using. If you want, I'd be glad to do a session on how to choose properly among possible joints based on an analysis of the four forces the joint must resist -- tension, compression, shear, and racking.

"...you should not scare away potential customers..."

But Halloween is so close...You're right, Paul. Just going for a cheap laugh. I didn't mean to imply the Ring Master is inherently dangerous. Then again, any tool is potentially dangerous in the hands of someone who doesn't know what he is doing. I'll do my homework before I do the demo.

With all good wishes,

[berry]

I for one would love a Sawdust Session on wood joints.

Nick, regardless of the semantics involved, are you suggesting that a biscuit joint has the strength (tension, compression, shear, and racking) of the other wood joints that could have been used to join two boards, as shown in the demonstration?

[paulmcohen]

"...you should not scare away potential customers..."

But Halloween is so close...You're right, Paul. Just going for a cheap laugh. I didn't mean to imply the Ring Master is inherently dangerous. Then again, any tool is potentially dangerous in the hands of someone who doesn't know what he is doing. I'll do my homework before I do the demo.

With all good wishes,

All right I am back to ordering one, I was hoping for the Holiday Catalog before the special sales end to see what else I need but since I did not show up today I will just order it.

I may not use it before your demo though, you can take credit for the sale.

[Ed in Tampa]

I for one would love a Sawdust Session on wood joints.

Nick, regardless of the semantics involved, are you suggesting that a biscuit joint has the strength (tension, compression, shear, and racking) of the other wood joints that could have been used to join two boards, as shown in the demonstration?

Berry
I'm not speaking for Nick but I don't think Nick was saying that. I think biscuits add some strength here and I think with the proper glue and technique a biscuit joint of this type will make this joint very useable. While biscuits have their own set of problems I still find them very useful at times.

I think we wood workers have a tendency to over engineer. I built end tables once and finished tables could have been used as engine stands.
I had to cut the material in the legs down by 60% and the rest of the table by at least 30% to make them look like end tables instead of small work benches. I can't recall anything I have built that isn't over engineered and able to support 10 times more weight or endure far more abuse than the normal object would ever be expected to endure.
Ed

[Ed in Tampa]

I guess I misssed the video. I personally haven't used biscuits in a long time. After Norm of new yankee pointed out that he was seeing a change in the form of the wood at the biscuit spot he quit using them almost totally except for miters. I have built some older projects with the biscuits in them and now for the past say 5 years I haven't used them at all. With todays glues I don't think your going to need them and if the boards are off that much maybe you need to pick different wood. Now and then I think it would be nice to have a biscuit cutter but I have passed. I had a pc and sold it to my brother and he lets me use it if I want. I just don't want to travel a half hour away just for something that I don't really need.

Scottss
As a faithful viewer of Norm's I think you may be overstating what he actually said. Norm still uses biscuits but is careful on thin wood to place the biscuit off center toward the unseen side so if the biscuit shape is telegraphed to the surface it won't be seen.
I have asked many people if they have ever seen biscuits telegraph their shape to the surface and no body has actually ever seen it happen.

Biscuits are another type of joint and they are just that. Biscuits are not the cure all for every joint nor should they be summarily rejected because in certain situations something else is better. Part of the skill of woodworking is knowing what joint is best suited for each situation, considering time, effort, pay back, look, strength and etc.
Ed