Weight limit for cope and stick joinery?

[Mitch schiffer]

I have some entry doors to build and im wondering if my freeborn cope and stick joinery will provide enough strength. These will be the first entry doors I have built in this manner. I have build passage doors this way in the past with no issues. The doors will be 8 ft tall 42" wide made of stave core white oak with 2 wood panels and a
insulated glass unit. The cutters I have will cut a 5/8 deep profile. I could possibly see if I can get a different center cutter to cut a deeper profile or if I have to I could do loose tenons.

[Matt Tebo]

Mitch,

I don’t think the cope and stick joinery is going to be able to withstand the stress of that door over time. It’s going to be very heavy. You can add dominos or dowels to the joint and add a lot of strength. Just my opinion.

Matt

[Phillip Mitchell]

No way. You need either long integral tenons (strongest), multiple long and large loose tenons (domino XL sized/or make your own loose tenons), or multiple long and large diameter dowels per joint (the way most production door companies do it)

I would never consider building any doors bigger than a small-medium cabinet door with just cope and stick joinery, personally.

A door that large and heavy needs the strongest joinery, thick jambs that are shimmed and fastened very well, and (probably 4) high quality hinges or you are likely to have issues with it sagging, etc over time.

[Jared Sankovich]

I don't trust cope and stick alone for glass cabinet doors, I certainly wouldn't trust it for passage or exterior doors, short of fully glued plywood panels. For a door that large I'd be using 14mm domino's at a minimum.

[Jim Becker]

Cope and stick is nice for the profiles, but you'll want to augment that with sturdy tenons for something that massive. You need the door to stay square and not rack over time from its own weight. Cut the mortises on both sides prior to doing your cope and stick and then use loose tenons glued in to take up the space and reinforce the joinery.

[Mitch schiffer]

I got a price the upgrade to a 1 inch tenon for my cutter stack. Is that sufficient? This will have a profile so I can't use my adjustable grover and tenonning head without having applied mounding wich id really like the stay away from on the exterior. This is the profile I will be using.
Screenshot_20220425-103503_Chrome.jpg

[Kevin Jenness]

I have some entry doors to build and im wondering if my freeborn cope and stick joinery will provide enough strength.

No way. Well fitted long tenons, spline or integral, will give you the glue surface and mechanical strength needed for longevity.

[Jared Sankovich]

I got a price the upgrade to a 1 inch tenon for my cutter stack. Is that sufficient? This will have a profile so I can't use my adjustable grover and tenonning head without having applied mounding wich id really like the stay away from on the exterior. This is the profile I will be using.
Screenshot_20220425-103503_Chrome.jpg

A 2.5" integral tenon is usually considered adequate for doors. I don't think 1" is really that much more than a stub tenon. Even dowells would be better than nothing.

[Jim Becker]

I got a price the upgrade to a 1 inch tenon for my cutter stack. Is that sufficient?

My opinion is that it "might" work for a more standard door size, but I'd personally want a beefier tenon for big, heavy doors of that size. A 1 inch tenon certainly provides a lot more glue area, but I'm thinking that a much larger tennon is going to help resist a lot more racking force from the physical weight of the doors.

[Mel Fulks]

I’ve glued and clamped , then used dowels. I used 1/2 or 5/8ths dowels, driven through a non -sharp hole in thick scrap steel plate. Dowels
swell with a little water mixed into glue. Too tight dowels break stuff. Made lots of doors and never had a failure. Mortise and tenon is good
when done carefully, but most chain made mortises are too big . Seen lots of wracked doors with non tight joints .

[Greg Funk]

Our door manufacturer used Freeborn cope and stick for all the passage doors 1-3/4 Poplar w/mdf or Cherry and they've been good for 20 yrs. The entry door was 44 x 100 x 2-1/8 Oak and I believe they added tenons for that but don't recall for certain. The main door hasn't changed (other than seasonal movement) in 20 yrs. There is a lot of glue surface on a tight fitting cope and stick door and I suspect few people have gone through any type of engineering analysis and testing to determine what is required. Most manufacturers build cabinet doors with cope and stick only and I think if you scale up the door to a passage size the math likely works out the same.

[Mitch schiffer]

I would like to find a way to build these reasonably efficiently. I don't have a slot mortiser but I do have a hollow chisel mortiser. Alternatively I could potentially get a custom cutter from freeborn to create a even deeper profile but the question would be how much is enough to be sufficient. The first 3 doors will all be for my own shop so I can experiment a little more with those then I could with a paying job.

[Kevin Jenness]

Time will tell. Sometimes it tells too much. An exterior door exposed to weather fluctuations and severely different conditions on opposite faces is in a different situation from a passage door. A thoroughly glued 1" deep cope and stick joint may hold a large door together, but what happens in 20 or 50 years? Deeply rooted tenons or dowels will still have some mechanical integrity if (when) the glue fails. There's a reason that you don't see minimal joinery on old doors.

If you are in business and expect to be doing more of this sort of work a slot mortiser, a Domino XL or a large shaper to complement your mortiser will prove to be a worthwhile investment, as will a copy of David Sochar's Small Shop Production of Custom Wood Doors.

[Mel Fulks]

Exterior doors sometimes look like they are coming apart at bottom rail. It’s usually just “ compression ring set”. Rain soaks into the raw wood
and swells the stiles. That smushes the wood into the rail , and the wood is permanently compressed into too narrow .

Bottom of door must be painted. And a drip edge is a good thing ,too.

[Mitch schiffer]

If you are in business and expect to be doing more of this sort of work a slot mortiser, a Domino XL or a large shaper to complement your mortiser will prove to be a worthwhile investment, as will a copy of David Sochar's Small Shop Production of Custom Wood Doors.

I do have a large shaper (7.5hp, tilting spindle, and sliding table). I would like to find a way to do this on the shaper without several other processes for the joinery. Im ok with spending a good bit of money on cutters if I can come up with a reliable processes to make these. I have about 40 doors total to make for this particular building.