Biscuit Joints

[Frank Speyerer]

In this month's Wood® there are plans for an arts and crafts style bench. It is assembled using only biscuit joints. Is a biscuit joint strong enough for a bench?

[DannyBoy]

Biscuits are generally used for alignment and the glue provides the strength.

[cosmocyb]

Frank, I looked at that too. I'm 6' 6" 300 lbs., I think I will just put the wood on the floor and sit on it rather that wasting my time putting it together. LOL

[Frank Speyerer]

I am also of the opinion that biscuits are good for alignment only and contribute little strength to the joint. That is why I question this particular use of biscuits in Wood®.

[woodhack]

I was puzzled too about this joinery method. Unlike a lot of woodworkers I believe there is some strength in the biscuit joint but I still wouldn't trust this to hold up long term.

[Frank Speyerer]

There are some interesting responses on the Wood® forum.

http://community.woodmagazine.com/t5/General-Woodworking/Biscuit-Joints/m-p/55087#M20910

Russ says..."Biscuits are for alignment purposes NOT for strength."

kmealy says...'I would respectfully disagree that biscuits are for reinforcing joints and not for alignment."

Jim says..."biscuit joints have held up as well as loose mortise and tennon joints."

[Lawrence Brown]

I guess that's one of those things that could be argued either way. Personally, biscuits used in that way would make me nervous, so I would substitute dowels if I was trying to keep it simple, just to satisfy my own fears of self-destructing furniture.

I also liked the way the cover of the magazine says "Build it easily with only basic tools". Funny, I've never thought of a biscuit joiner as a "basic" tool, but maybe I just haven't been watching Norm enough

[shooterscott]

Oh man I needed a laugh tonight, thanks so much.

Frank, I looked at that too. I'm 6' 6" 300 lbs., I think I will just put the wood on the floor and sit on it rather that wasting my time putting it together. LOL

[Bombarde16]

Is a biscuit joint strong enough for a bench?

I suppose (if one had some irrational phobia against M&T joints or if you're working with some rare stock and don't have the extra length for M&T's) you could do a preliminary glue-up using biscuits and then come back with a drill and peg stock to turn biscuits into through-dowel joints.

But on its own, no. All the joints in this project are butt joints (end grain to long grain) which need the shearing and racking strength of solid wood joinery. I'm 160# after a healthy meal and I wouldn't trust this design.

[Frank Speyerer]

I forwarded my question to Marlen Kemmet of Wood® his detailed reply was: "yes". Brevity is the height of clarity.