Replies

1. 
   IdahoDon | Apr 04, 2012 12:02am | #1

   I read an article a few years back that pressure tested various door joints and while the mortise and tenon joints are tops, they aren't all that better than a large buscuit joint.  Unless a door has dimentions that make it especially hard on joints I just use buscuits.  As for the tenon material - it probably won't matter - tests show pretty similar results with hardwood or softwood tenons.  As for the depth of the mortise I usually go 1-1/2" ---easy to route.

2. 
   RalphBarker | Apr 04, 2012 11:07am | #2

   draw-bore or not

   Using a draw-bore pin on an M&T joint, it seems to me, is more common with tables and benches, where there is more likelihood of racking forces being applied. I've also seen it done on cabinet doors and picture frames, where it also serves as a decorative effect. I'm not sure that it would be necessary on interior pasage doors, unless they are unusually wide.

   The depth of the mortise (and the corresponding length of the tenon) should probably also relate to the size, weight, etc. of the door. I'd think in terms of at least half the width of the stile, or perhaps more. I've seen old doors where a through tenon was used, but trimmed flush, of course. The fact that such doors have lasted a hundred years or more may say something.

   Loose tenons shouldn't be (loose, that is - shouldn't they be called "tight tenons"?  ;-) ). And, I think they are less strong than a tenon cut on the rail component. There is something about the continuity of those long fibers working together that appeals to me. But, I don't have any scientific evidence to support my opinion, just intuition.

   As to the material for the pins, should you decide to go that way, I don't think a harder species is necessary. The grain of the pin is going in the opposite direction, so you're looking at the shear strength of the pin holding the joint together. Additionally, a difference in seasonal expansion/contraction might be an issue if a vastly different species is used for the pin.

1. 
   IdahoDon | Apr 05, 2012 12:04am | #4

   That article I read did have a cut tenon as the best option, but just barely - something like less than 4% difference in force required to break the joint.

3. 
   roc | Apr 04, 2012 09:07pm | #3

   In this case Norm is a great place to start

   http://www.symionic.com/newyankee/index.php?id=53#ecwid:mode=product&product=7916676

4. 
   Rob_Sp | Apr 05, 2012 08:19am | #5

   Door

   Whether loose or integral tenon I would consider 1-1/2" minimum, 2" or more would be better. If loose, carefully size for a snug sliding fit, bullnose the edges of the tenon, route the slot length or mortise in the rail to fit the tenon tight on the edges to get the most strength in the long grain to long grain fibers, the slot can be made a slightly longer in the stile to allow a small amount of adjustment when assembling. Use an up cut sprial bit for this.

   Personally, I prefer traditional joinery for this, you can cut the tenon in two cuts on the tablesaw, the first standing on end against the fence to cut the faces, I use two blades with spacers and shims to cut both faces in one pass, but you can do it with one blade and two passes by repositioning the fence or flipping the rail if working from the center. Then set the fence to the tenon length and cut the cheeks off. All parts are then profiled and traditional square shouldered mortises are cut into the stiles. The stiles and rails are then haunched and mitered at the joints or haunched and coped with a gouge, my preference and easier than you might think if you have never done it. Here is a good article on this technique: https://www.finewoodworking.com/SkillsAndTechniques/SkillsAndTechniquesPDF.aspx?id=2427

   Another method is to is to mortise and tenon square shouldered with a slot only and then put a plug in the slot to support a mitered applied molding which will form the groove for the panel, this method simplifies construction, and also allows for the use of profiles that would be impossible to cope. See drawing.

   Use pins not dowels, cut them square to fit the holes then make them octagonal with a hand plane , they must be carefully sized so to be driven in (use a steel hammer for this), too tight and they will not drive through.

   Drawboring is a romantic notion and would be useful if you don't own a set of clamps, however clamping the assembly up and drilling/pinning the joint in the clamps is just as effective over the long haul and much easier. In my opinion, the initial tension gained by drawboring will be lost over time, it is wood after all. Speaking of clamps, I would invest in a few I beam type bar clamps. Black pipe is great for air and water lines, but the cheap pony clamps will tend to spring and pull the stiles out of plane, so you will have to be careful if using pipe clamps.

   Best of luck

   Rob

   
1. 
   roc | Apr 05, 2012 11:03pm | #6

   I Agree

    >Black pipe is great for air and water lines, but the cheap pony clamps will tend to spring and pull the stiles out of plane<

   High Quality Clamps Are Worth the Money

   Can be hundreds of dollars for enough to do some thing with but heck, that is the price of a hand plane.  You won't regret the investment.

   Makes handling the glued up unit easier to.  See the photo.  Can't stand pipe clamps on end and  clamp up like this without a bunch of hassle.  And/or if you glue up flat, and can lift the glued up unit, you can then stand the unit on the flat ends of the clamps and set it aside and glue up another unit flat and then stand it out of the way.

   Just watch Norm or Scott Phillips episodes to appreciate this feature.

   I have pipe clamps too by the way.

   
5. 
   timhorchler | Apr 21, 2012 08:58pm | #7

   Now get to work

   Thanks for the input.  With Summer upon me now I will not get to this before early Fall. I will report back with pictures.

   Tim