Greetings.
I am in a bit of a bind and am looking for input/advice on exterior door construction. To preface I have spent 5-6 hours on the forums/knowledge base reading prior exterior door posts and have gotten a lot of information. I have an interior designer who has contacted me about building an exterior door. I am a cabinet/furniture/cnc guy and so not an experienced door maker. The problem is that this is the second time that this interior designer has contacted me about doing something and I said no the first time as that project was outside of my wheelhouse. I really would like to get in with her as she is well known and doing quite well, and if I say no a second time, I don't think I will hear from her again. So, to me, the opportunity outweighs the risks. That said it seems to be a pretty straightforward door. 2-8x6'8x1-3/4 frame and panel. Bottom, middle, top rail. 2 panels. There is a 'speakeasy' (non-functioning) window in top panel with a brass 'porthole' look so this is definitely custom. My thought had been to do a stave core of plywood (CDX or radiata) laminated similar to the timberstrand/LVL concept, but I don't see anyone doing that on here so now I am thinking just using Sapele for stave core and edging/veneering with white oak. Using shop sawn 1/8"-5/32 veneer. I would use either Urea resin or Epoxy for all glue joints. Simple T&G cope and stick profile which I would be adding dowels to reinforce at joints. The panels are going to be reeded texture with rabbets to fit into the grooves of rails and stiles. I have seen reference to panels being made with 5-7 ply construction. Can someone expand on that method? Or for this size door should I do separate interior/exterior panels solid oak and separate with plywood? I assume that the panels would not be glued to the plywood. I would just be making the slab. This is being installed in an existing door jamb by others. I appreciate the advice, and do understand the risks. Thanks as always.
Dave

If you are going to use white oak veneer then I would use white oak for the stave core as well. Use plain sawn for the stave core and quartersawn for the veneer and everything will have the same orientation once married. Another approach is to use two or three layer solid wood for the stiles/rails. If you can get quality stock this would be easier and faster.

Either glue you propose would work well. I use Plastic Resin Glue for the stave core and veneer and epoxy for the joints. I prefer loose tenons for the joinery because I'm set up to cut the mortises but dowels work well, too.

I use separate panels for the outside and inside, back to back. That way, both panels can better accommodate seasonal expansion/contraction. If you separate the panels with plywood definitely do not glue them to it. Personally, I don't see the rational for that approach. I'd rather have thicker solid panels.

Do you know where the door will be located? N, S, E, W. Covered by a porch? Direct sun? Storm door? Make sure you know who's on the hook if something goes wrong.

Good luck.

John

In Canada doors like that wouldn't last .I know David will chime in hands down best doors and experience .

If your not set up with a shaper , I mortise and tendon simple joinery time proven

The other thing is I laminate 3 pieces of 4/4 together makes for a 2 1/4 thick door will not warp also feel really solid on a ball bearing hinge

Stave seem like so much work and expoxy etc a lot that can go wrong

John
Thanks for the response. I have seen some comments on the 2 ply vs 3 ply for R&S. For a 1-3/4" thick door would 2 ply be better? I assume that the boards would need to be quartersawn. I am waiting to hear back from the designer on sun/rain exposure. I am guessing that I would be on the hook if the door warps. I will at least have that conversation with her about wood doors.
Kevin
Since it is an existing door, I am stuck with 1-3/4" thick. Would you do a 2ply or 3 ply with that thickness?
Thanks

I would never do an unbalanced lamination of even number of plies. I might add that learning the entire process of making entrance doors from a forum will be difficult. You didn't answer the question of the position of the door. Frame and panel doors that are exposed to direct rain can easily have a rotting problem from water seeping into the panel groove and soaking into the end grain of the panel.

3 ply no question you have a sandwich cabinetmaking 101 ,even going to 1 3/4 you will get it lazer flat lots of meat .

Glue I found out the hard way Tribound 11 failed it happened on my personal door .The joints get soft and open up once it gets wet when that happens the door is finished

I use Elmers exterior an underrated glue great for open pores like Mahgonay the glue is thick realy gets into the pores

In laminated stiles and rails all the plies run in the same direction so it's balanced no matter the number of plies. I don't think it matters whether you use 2 or 3 plies. As long as your wood is quarter or rift sawn and laid up as mirror images the glued up sections will be fine. In any case, you should check with the designer about the exposed edges of the stiles. If a glue line in the center for 2 layer construction or 2 glue lines for 3 layer are unacceptable then you will need to mill a dado and glue in a thin section of wood so that it looks like a veneered door.

M&T, loose tenons, dowels - with epoxy or UF glues all will give a durable door if the workmanship is good.

John

First bit of advice is to hire an experienced door maker unless this is your door or that of a friend. Your inexperience shows when you state that you might be on the hook if the door warps. Yes, is the answer.
2 ply or 3 ply stiles and rails do not matter, but you want solid since it is less parts to make.
Mortise and tenon is the only way to make doors, in my opinion. Cope and stick with appropriate tooling. Dowels are OK if you have the competent machinery to make the accuracy. Do the math on glue surface to see how the two methods compare. Glue surface is what you want.
Panels? After 50 years, I have given up on all the tricks, voodoo, and crossed fingers. I build a panel with a man made core, usually 1/4", then a ply of solid wood on either side of the core, to raise. Then a cross band of veneer on top of the solid, with grain at 90 degrees to the solid. Then a face ply running the same direction as the solid. Press them all up, with epoxy, and then size and raise. These panels are plywood, and can be glued into the frames. Honestly.

There are degrees of door building. Most methods have one or more serious flaws in their methodology.

Read my comments in the previous thread about 2 vs 3. Its not real.

Like David we experimented over the years with various ideas. We settled on effectively the same as David. Shop made plywood. If you aren't using epoxy for all of the joints in an exterior door the onus is on you to argue against. People have been building boats out of epoxy for 40 years.

Absolutely DO NOT face glue solid laminations to make an exterior door, or any door for that matter!!

I suspect any good suitable wood ripped and flipped would make a good core, edge with your oak and glue your 1/8" faces. We personally use a finger-jointed western pine for our core. Any good type 1 exterior glue would suffice as long as you can machine accurately for good bonding. Yes dowels are perfectly acceptable, NO you don't have to mortise and tenon.

Let your inside and outside panels float, once again good practices as to panel staves and machining will dictate success. I do like to seal the end grain of my panels prior to construction. On a 1-3/4 door it may be difficult but a 4mm plywood between the panels is also a nice, floating also of course.

As for epoxy, if you have one door and it will get your juices flowing go for it. Otherwise I think your wasting time and money, at maximum a good urea resin is more than ever needed.

As with any door, exposure to elements and quality of finish are also huge factors in it's success. Whenever someone says they "need" to replace their front door I ask why, amazing how many applications aren't suitable for a wood door.

As you can see, opinions vary widely, and there are expectations of choosing sides. If you do build the door, you will be expected to resolve any problems with it.
I suggest you let science and experience help you determine how you work, rather than emotion and volume.

How it started with me using 3 pieces of 4/4 was by accident I couldn’t get locally at the time 8/4 .So I lamented 3 pieces and ended up 2.5 thick also I was able to use a full ¾ thick panel with no lamination most time through a small lift of African Mahogany you can find a 14 wide board .
The door looked impressive with extra ¾ thickness I used 4 ball bearing hinges and the door was solid a pleasure to open felt safe .

When I open my door I did not try and compete with pizza box makers I tried to rise above the mass produce .Its worked but in these parts its getting hard because Contractor are making decision on interior so that means cheap the big houses look empty and dead .

Also I had my start in antiques in Montreal lots of history with craftsman’s unreal work there .Doors 100 years ago were mass producing doors out of wood with through mortise and tendon in houses outside inside you name it ,it was no mystery how they were made .I restored a couple of the exterior door I would take a door down and barley carry it .Were forgetting how to make things out of wood .

forgot

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