Replies

1. 
   RSRose | Aug 14, 2002 10:51am | #1

   MSD,

   It all depends. If you want to know that you've done it right, the M&T is the best way. If you just want to get done quickly, biscuit.

   Although, for just 2 doors, the time difference won't be that much. While the M&T is best, the biscuit jount will probably outlast you, if done right.

   Rich

2. 
   BG | Aug 14, 2002 01:34pm | #2

   I have no specific knowledge to add to this discussion but I kinda wonder, will the biscuits stand up to all the perpendicular pounding that these doors will receive?  If you put the three together they probably are about the same thickness of the tenon...but they only go in about 1/2".  With the body blows these doors receive and, the psi on the joint, will the rails and stiles hold up?  thanks 

   
   

   ---

   Edited 8/14/2002 6:35:33 AM ET by BG

1. 
   dhpascoe | Aug 14, 2002 03:23pm | #3

   Biscuits can have amazing strength. I've personally tested a number of joint combinations. However, one of the things taht causes the joint to get tight is the swellling of the biscuit from water in wood glue. Over time they might lose that tightness, say in air conditioned environment. For an exterior door, that joint will swell even more. I suspect the standard MT would not be as good for this reason. Note that commercial doors are doweled along with a cabinet lock joint along the long grain. Even this method can fail. A through tennon would probably be best for an exterior door.

   Dave of Fla.

1. 
   ScottDoten | Aug 14, 2002 05:27pm | #4

   I was not sure how an air conditioned environment, more importantly the ever changing environment in and around a bathroom would effect a biscuit joint.  

   Thanks everyone - MSD

1. 
   dhpascoe | Aug 15, 2002 12:17am | #7

   Well, you know what a bear of a problem outside doors are. Humidity changes in the bath are usually rather short lived, perhaps unless you've got three daughters all using the same bath! I have a maple cabinet in my bath, one of my first projects in which I experimented with numerous joint types, including stopped tennons and splines. It is many years old and none of them have moved, but the thing is urethance varnished all sides.

   My take on it is that biscuits would probably be fine for inside doors, but I would be inclined to add a few dowels for insurance. Easy enough to do.

   Dave of Fla.

3. 
   rreeger | Aug 14, 2002 10:23pm | #5

   Didn't I read somewhere recently that there is not a substantial difference in strength between a two- and three-biscuit joint.  If so, wouldn't that save a little time as well?

   Just wondering?

   RR

1. 
   RSRose | Aug 14, 2002 11:55pm | #6

   Yes,

   It was a recent issue of FWW, don't know which one.

2. 
   ScottDoten | Aug 16, 2002 07:05am | #9

   Yes, there was an article in FW giving different joints stress test/measuring their breaking points of each joint.  The M&T and Biscuit Joint were in a close race.  Is there anyone out there who knows what issue I am referring to?

   The conditions in which my project will be subject to (moister) using multi biscuits is not recommended.  Therefor, I will use the M&T.

   MSD

1. 
   rreeger | Aug 16, 2002 02:46pm | #10

   MSD,

   Maybe the issue I am thinking of is the March/April 2001 issue, #148. Article on page 74, "Testing Joints To The Breaking Point", by Bruce Gray.

   It sure seems that I have seen this more recently, however.  Unfortunately, I am unable to find it.

   I will keep searching, in my spare time.  Hope this helps anyway.

   RR

1. 
   BenM | Aug 16, 2002 08:32pm | #11

   I think the issue you want to see may be No. 111 (March 1995).  I'm almost sure the article was the one entitled "Choosing the Strongest Joinery for Doors".

1. 
   ScottDoten | Aug 16, 2002 09:30pm | #12

   Rookie & Ben,

   Those were the articles I was thinking about/referring to.  How did you locate them so quickly? Was it the reference issue FW puts out ever so (?) or on the internet?Thanks you just jogged my memory about the reference issues.  

   MSD

2. 
   rreeger | Aug 16, 2002 10:04pm | #13

   MSD,

   I searched the Fine Woodworking site.  Had to perform a couple of different searches but found it.  Cannot remember the exact terms/phrases I searched for though.

   Glad I was able to help!

   RR

3. 
   BenM | Aug 17, 2002 12:11am | #14

   In this Rare case I had it memorized.  Because it was in the first issue of FWW I ever bought. (Anything I know about older issues are from the various reprints that have been published in book form).

4. 
   Andrew | Aug 15, 2002 12:22am | #8

   I remember reading in a FWW issue that a double biscuit joint could take a load of approximately 1500 pounds before it failed, however, because of the stress put on the joint i think that a mortise and tennon joint would be a better choice.