Biscuits ?

[Al Willits]

Having just got my PC biscuit cutter friday, I spent the weekend playing with it, learnt a couple of things.
Like finding out a set of biscuits were on the wrong side of the board, in the middle of gluing up makes for some interesting lanquage, and being grateful for whoever invented slow drying glue.....:)

I did read in the directions that you should use the correct size biscuit for the board your using it on....but it fails to mention what is the correct size biscuit????
I was using it on 3/4" plywood and used the FF biscuits but wondering if they were to small...anyway, is there a basic rule of thumb for sizing biscuits?
tia
Al

[Hoa Dinh]

is there a basic rule of thumb for sizing biscuits?
Yes - Use the largest ones possible.

[Pete Harbin]

And mark their location clearly!

I once glued up some beautiful cherry into wide boards for a Shaker cradle, only to cut the boards to size...right through the biscuits...:eek:

I had spent about an hour culling through the cherry at Paxton's to find these beautiful boards.

Pete

[Mitchell Andrus]

And mark their location clearly!

I once glued up some beautiful cherry into wide boards for a Shaker cradle, only to cut the boards to size...right through the biscuits...:eek:

I had spent about an hour culling through the cherry at Paxton's to find these beautiful boards.

Pete

We've all done that once.

[Mark Rios]

Biscuits?


Gravy.....

[glenn bradley]

All kidding aside, the largest ones possible is correct. FF is for face frames where the stiles or whatever are smaller than say, table-top panels and the "T" joint would be narrower than the biscuit. Center the biscuits in the thickness when possible. Folks who doubled up on biscuits (one over the other) on thicker (but not thick enough) stock in an attempt to add more strength have posted here the result; biscuit too close to the surface, biscuit swells when glued (like they're supposed to) and creates a bulge or worse on the surface.

I use 0's for face frame to carcase joints, 10's for panel sections or shelf/top to side joints and FF for rail to stile or mitered corner joints.

[Al Willits]

Thanks, trying to shorten the learning curve a bit.
So it looks like I should have used #10 to join two pieces of 3/4" plywood then?
I was more concerned with how deep into the piece I can go with the cut, like if the woods 3/4", a 1/2" cut is max???
Thinking the larger the biscuit, the deeper the cut.

Al...who assumes you mean a milk gravy with bits of sausage in it?? :D

[Tyler Howell]

Keep them babies in a sealed dry place.
One suggestion is (Unused:rolleyes: :D ) kitty litter.
They will start to swell on ambient humidity.;)

[Mike Henderson]

I essentially never use biscuits for edge-to-edge gluing - even edge gluing plywood. The glue bond is plenty strong without it and for alignment when gluing I use cauls.

If I had to glue plywood in such a way that the layers didn't align - that is, the plywood was turned so that the layers were end grain to edge grain, I might use them.

Mike

[frank shic]

al, the only two biscuit sizes i've used are the 20's and the FF's for face frames. the 20's will work just fine without cutting THROUGH the 3/4" plywood. it will definitely cut through 1/2" - i found this out the hard way on my newly created table saw extension table!

[Ted Miller]

I am with Frank, I use #20s most of the time on 3/4. As Glenn mentioned I made that mistake before, to close to the surface and after swelling you could see the impression of the biscuit, oops...

[Al Willits]

20's it is then, thanks.
I figure time will tell on most of them, but I have a project with 3/4" plywood and wanted to get that done before I play with different sizes.
These are not for end to end joints, its a cabinet and most are end to face (right angle?) joints.

Al...who seems to be making to much scrap, and to liitle projects lately..:)