Now questions about building interior doors

[mreza Salav]

Ok, I've asked a bunch of questions about building an exterior door (for our to be built new house). Based on the collective wisdom of people on this board I am not sure yet I would want to have a wooden exterior door (vs say fiberglass). While debating that I am posing questions about building interior doors for a house.
There are going to be about 25-30 doors in the house (including the closets). Since closets are almost all walk-in, I am leaning toward using doors instead of bi-folds.
Have checked a few door suppliers for "wood" doors (well these are veneered with MDF core or plywood at best). They run at about $300-$400 a door (pre-hung) and they are not "good" doors (they want $200-$250 for a slab). Hence, I'm considering the option of building them myself again.

Wood: most likely maple (as it would be easier to find trim/casing/baseboard/etc to go along with).

I am thinking about something that is not too complicated to build in that quantity and keep the cost a bit down. So I am thinking of using plywood (flat) panel
instead of raised panel, with solid wood rail/stile and perhaps applied mouldings, maybe something like the following (except the raised panel):



My thinking is to make the rails/stiles by laminating two layers and use plywood for the panels, with floating tenon joinery and apply the mouldings at the end.
Is this reasonable (both sound and easy) way of making it? what thickness of panel should I use? I was thinking 3/4" but that might be too thick for a 1 3/8" thick
door (the groove would be too wide in the rails/stiles). Should I use a thinner panel or should I make the door thicker (1 3/4"?)
Is it better to glue the plywood panel to get a more rigid structure?

The next question would be if I will be able to find moulding with the proper "inset" to apply around the panels. I see mouldings for this purpose with a 1/2" inset (i.e. the step from rail/stile to panel should be 1/2"). That would mean building a 1 3/4" door with 3/4" panel.
I could use a rails/stile router bit to get a profile but I'd like to keep making them simple/fast.


Again, advice/comments would be appreciated.

[David Kumm]

By the time you purchase and apply the molding, it will be more costt effective to get a rail and stile shaper combination with a profile. Good straight 8/4 will make a 1.75" door that is straight and a lot less work than gluing two pieces together. If you go the two piece route you want to avoid Tantung cutters as they dull with a glue line. I would make 1 .75" doors for the main visual ones and the ones used most and cut corners on the closet dorrs hidden from main view. 20-25 doors takes a fair amount of time no matter the type so do the ones will see the most first. I'm not a fan of ply panels unless they are being painted because they always look different from the solid wood unless you resaw your own veneer and that adds lots of time. You really have to watch the ply for crease lines as they tend to only show up after they are part of the door. I would go 1/2" on 1 3/8 and 3/4 on 1 3/4. Actually I'd go 1 1/2 rather than 1/38 if using 3/4" rial and stile stock laminated. No reason not to if doing your own thing. Emtek makes decent ball bearing hinges for a reasonable price as well as matching hardware. Hinge quality adds a lot to the use of a fine door. Dave

[peter gagliardi]

Don't know what tools are at your disposal ? That will determine the best path for you. However, a simple solid wood true mortise and tenon door is pretty straightforward especially with applied moldings rather than cope and stick style.
If you want 1-3/8" doors, a 7/16" tenon is ideal which would be almost perfect for a 1/2" ply panel, as it is undersized from true 1/2" . I wouldn't bother with a laminated door, or stave core- unless you are limited by stock on hand.Complete waste of time IMO as I have several hundred doors out in the field made the good old fashioned way with zero issues. If you take your time and pick your stock properly it should be easy, though not necessarily quick. You should be able to get 6/4, but would be better with 7/4 stock- some yards have, some don't . You can make your own flat mold on a W&H machine pretty slick for short runs such you have. For a really nice door, thru M&T wedged is very sweet.
Peter

[mreza Salav]

Thanks Dave and Peter. I have a shaper and good router table setup.
My major wood supplier here has maple in 4/4, 5/4, 6/4, 8/4. Main reason for thinking to use lamination was to make it less likely to wrap.
The main reason I'm thinking of using plywood panel (vs solid raised panel) is the added time to build them (and make the profiles).

Is a 1.5" thick door standard (e.g. typical hardwares would fit it)?
I don't see a reason why not glue the plywood panels in, or is there one?

[Mark Bolton]

Gosh, I havent installed a bi-fold door in even a high-ish end home in perhaps 15 years.

I know your weighing cost vs. quality and Im sure the reward of making your doors would be very high but I just cant see how you could compete with even a door several grades higher than what your looking at (250+/slab).

One would of course assume your quality will be a good bit higher than a massed produced door (not sure about the door in your image), if you are considering this as a means to save money or even compete with the pricing of nearly any commercially available doors I have a hard time believing you will achieve that goal. Will you come out with a better door? Most likely. Will you have the reward of having made your doors? Yes. Will you save money or even be close? I just cant see it.

The quantities in which you'll be buying material and your time will likely make these doors very very expensive. Very rewarding, but far more expensive than any purchased door...

It may be worth investigating some other door suppliers if cost vs. quality is your motivation. Of course if your just really looking forward to making the doors its all moot.

[Jeff Duncan]

You've gotten some great advice already and I would second a lot of it. 25 - 30 doors is a LOT of doors for someone who hasn't made one yet, and you should plan on spending several months making them. If your gluing up for thickness I've always been told to go in odd numbers....3,5 etc.. However I'd agree that if you go and pick your stock out you can get nice flat doors out of 8/4 stock. You want to stick with normal thicknesses, 1-3/8" is very common though I would never build a custom door that thin. 1-3/4" is my most common size with 2-1/4" popping up now and then. I also agree with Mark, unless your unemployed and have loads of free time on your hands, it's going to be more costly to make your own doors than to buy them. If you can pick up a good quality maple door for $300-$400 that may be your best bet. FWIW there's a reason your average home is filled with cheap hollow core doors these days In my shop, which is pretty well equipped, it would take me a solid month to push out that many doors prehung w/ jambs....oh yeah, if your using maple for the doors and trim....you'll be needing to make your jambs too

Now I'm going to throw out my opinion as a cautionary step, I would not attempt to make these kind of doors on a router table. A small cabinet shaper can manage them but it's going to get a workout! As far as the panel molding that's pretty simple, buy one that has the correct thickness you need and then rabbet it on your shaper to fit. You'll want a good amount of infeed and outfeed on your jointer as you want your stiles dead straight! Also be ready for a workout as your talking easily several hundred bd. ft. of maple which you have to machine and handle....trust me when I say those doors are going to be heavy!

anyway that's it for now, I'll follow along to see how your doing
JeffD

[mreza Salav]

Mark, I appreciate any advice that will help me along the way. I recently built a series of cabinet doors for a small kitchen and two bathrooms (I have done a number of furniture/cabinets but it was my first "kitchen"). The cost of wood was about $160-$180 for 19 doors and 4 drawer fronts, which was lower than my own estimate, although the cost of "finish" was way more than what I thought (photos are with my cell phone):

cab1.jpgcab2.jpgcab3.jpgcab4.jpgcab6.jpgcab7.jpgcab17.jpg

For the interior doors, I am estimating that I would need about 30bf of solid lumber (assuming 35% waste) plus 1/2 sheet of ply for panels, per door.
I can get Maple for about $2.5/bf and each sheet of ply for about $55. So the cost of material per slab should be about $100, plus my time, tooling, etc.
If I am wrong in my estimates I'd be glad to learn where.

Just to add: i'm a hobbyist and the above cabinets took me about 20 hours to build (from rough lumber to finish ready).

[David Kumm]

Building your own doors is always about matching grain and building something better as it is impossible to match price with a stock dowell construction door. The best bang for the buck is when building odd size custom stuff. I have big jointers, planers and shapers but they still take lots of time. I use a Felder slot mortiser but that still takes at least 30 minutes per door and the bits won't last 25 doors. There is a lot of sanding- as you know - and finishing. Glue up takes 20-30 minutes. Mortising the hinges- on the correct side- and building the jamb take time too. Not discouraging you but I remodeled my 3500 sq ft office years ago including 13 8' Walnut doors and trim and my wife has often told me it was the year from hell as there was no time for anything else with the family. Spend your time on the stuff you will look at and appreciate every day as there is a trade off. Dave

[Mel Fulks]

The door picture you posted is fairly showy and would be a good feature in some places . Forget the recent idea that everything has to match, in the typical asymmetrical room a closet door in a corner should have a plainer look . I would use stain in just a few places or none. Many find stained wood trim all over a house just too dark , even light colored stains.Mortise and tenon will not bring any extra money when you sell the house ,I would not use them on this job. There are many well made features in modern houses that become liabilities because the designs are poorly thought out .

[Andrew Hughes]

Doors take a lot of space to make.The most I can make at one time is two then I lose all my serenity.Most of my doors are outside entry gates I have done a couple front doors.Take a lot of room for all the stages.And a very flat assembly table.Have you seen the thread at lumber jocks on doors? Some neat stuff.
good luck with you build

[mreza Salav]

Dave, good advice as always. My wife will probably not like the idea of me spending a lot of time in the shop after I get home from work! The good thing is we are in the blue print stage of house so I have many months (maybe a year?) to do the things I go at. Might take on the task of building one to see how long it would take, although I'm sure building 30 isn't 30 times one but gives me a sense of how long it actually takes to do it start to ready to finish.

Thanks to all for the comments.

Any advice on the two questions I asked:

Will a 1.5" thick door be fine (e.g. typical hardwares would fit it) or it has to be 1 3/4"?
I don't see a reason why not glue the plywood panels in, or is there a good reason NOT to do it?

[Mel Fulks]

No harm in gluing in the plywood panels .Ive done it and seen posts of others doing that ,too. Sometimes I just glue the bottom one for a little more strength. Personally ,I don't see anything wrong with 1 and 3/8 inch INTERIOR doors. Old doors were often surprisingly thin.

[Mark Bolton]

Mark, I appreciate any advice that will help me along the way. I recently built a series of cabinet doors for a small kitchen and two bathrooms

Ive looked at your images in both threads and I am in no way doubting your ability though a router table is going to be little to no use. But the simple fact is it comes down to one thing and one thing only and thats are you romantically attached to building your doors, a door, some doors, or whatever, or not. Because there is no way in the holy hot place that your going to save a dime building your own doors. So once the concept of saving money is out of the question (because you in no way will) then you can make a real decision.

We all know the accounting that goes on, wood, glue, perhaps some tooling (oh... but at least I'll get the tools out of it), some electricity, wear and tear on your equipment... add all that up and your door will be cheaper. Then (this is one of my trademarks) assign $5 an hour to your time. _All_of_it, planning, driving after and sorting wood, packing it to the shop, getting other materials, and so on. $5 an hour to every minute, and you'll be in the hole in a flash. Whats left after that is the romance.

Im not trying to rain on your parade but it just comes down to is this a labor of love, or not. We can all devalue our labor into the negative (provided we have another source of income). But approaching this in any way as a cost savings endeavor is deceiving yourself.

I come from a position that makes me bias out of the gate. I have been a GC for a long time and cant count the times I have had homeowners, friends, and so on, that think they are going to chunk off these massive portions of their home construction. Many of them think they will do it all AND be their own GC AND work a 60 hour a week job. It aint gonna happen. There are so many decisions, distractions, diversions, and so on that just go along with building a home using a GC most individuals would be hard pressed to build a few accent pieces, or trim out a couple rooms, and so on. Of course there are some that have done it but the timeline will be impacted for sure.

Again, my input is if you just really want to build your own doors then have at it. It has nothing to do with cost, you just want to make your doors. Personally I have a pretty well equipped shop, not as well as Jeff, David, etc. but pretty well, doing this full time, and Ive been doing this work for nearly 20 years, but unless I was extremely well positioned financially (in which case why would I be doing this work ) allowing me massive amounts of free time, if I were building a new house today the last thing I'd be thinking of doing is building my own doors. But thats just me. I'd be focusing on some nice built-in's, maybe vanity cabinetry, or whatever, but to me, doors are too cheap to buy. The other things I can build I most definitely can compete on value AND actual cost (including labor). But again, I look at it from a different perspective where I have no choice but to assign a value (dollar value) to all my time.

[David Kumm]

Most hardware will work with 1 3/8, 1 1/2 or 1 3/4" doors since they work with either common size. My Hickory doors are 1.5 because I can't lift anything thicker. I found it easier to adjust the dimension to the material than vice versa. The hinge depth is adjustable too. I think your plan of building one is good. You learn a lot and a stock 32" will fit wherever you decide to put it- depending on how it turns out. Very easy to get out of square so be particularly careful if doing cope and stick that the cuts are exactly at 90. A little off is a ton over the length of the door. Dave

[Peter Quinn]

First a few numbers. 30BF is a fair estimate per door with flat panels, assuming 6'8" height, average 2'8"-3'0". Also work towards 10-12 man hours per door from rough lumber to finish sanded. Your first door may not go that quickly, but that would be my goal. Yes, 10-12 hour per door, compared to the average kitchen cabinet door 5 piece takes me 1.25-2 hours max on a batch in a small shop, less in a well equipped pro shop. You might get it down to 8 hours, but I'd be surprised. Plywood panels are fine, maple faced MDF is my preference, it stays flatter, the veneers are generally very good if ordered AA, easy to work with for a batch of flat panel doors with panel molding. On the panel molding, you should be able to buy what you need from a decent millwork shop in your area, even a short custom run might be viable on that volume. I don't see a rabbit going over the rails and stiles there, I see a molding whose back is set flush with the panel groove and whose edge butts the rails and stiles. A molding with a rabbit that rides over the face of the door is a bolection, that one is just a wide panel molding, just a bit easier to to do.

You could glue in the panels, or let them float, I've done both with no noticeable difference. If you want to use a raised panel you have to run a spline into the panel groove. Basically you make a square edged frame, glue it up, fit plywood or solid wood splines for each groove, whose projection from the groove edge is roughly 5/8" narrower than the panel molding, glue this in, then make the panel moldings up as picture frames and either glue or nail and glue these to the splines. First one side of the door is done, then you flip the door (after glue is cured) , drop the panels in, they will be supported by first set of panel molding, you glue the second side in....done. Wide fancy molded profile not possible with cope and stick, the panel molding becomes the panel's groove through that spline process. Flat panel is much faster, you just put the flat panels in during assemble and glue the panel molding picture frames to the panels. I've done a few where we used splines with MDF panels, let the panels float, you can sure do that too, seems like overkill to me.

On the laminated thing, I'm on the fence. Maple is not the most stable species I can think of, it moves a lot more than some. Careful laminations, at least for the stiles, would probably help with that, though I too have been taught that the best balance is achieved when even numbers of layers are glue to a single core, like plywood, so always an odd total number of layers. I've heard of two ply laminations for doors, seems to work, I have never done it. I have milled plenty of 8/4 maple stiles, and they stay straight enough if you keep the humidity fairly constant, keep them out of direct forced hot air or such. I'd probably start by making a door or two with solid 8/4 to see how it goes before committing to that much lamination work.

On the door thickness, the custom doors I make at work are all 1 3/4" unless they are made to match older skinnier doors. We have done 1 1/4" and 1 3/8", but for high end new construction, its all 1 3/4" these days. For my own home I make them 1 1/2". I have a metric set that make 40MM doors, sanded they land right around 1 1/2" which works fine with the proper hardware (I can't say all hardware will work but there is plenty that does). I've also installed a 1 5/8" door that I got when somebody screwed up a 1 3/4" door.....I just kept sanding until the problem was solved! Which leads me to the ernest suggestion that you make friends with a shop that has a wide belt sander...you can build 30 doors without one but it will take a lot longer and be a lot less fun.

On the frame I'd use dowels if you are set up for that.....yes I said dowels. 6"X 1/2" maple dowels, 2 to 3 per rail/stile intersection. Are mortises stronger, sure! And for exterior thats highly advisable. A M&T door will also come in handy if a nomadic band of warriors tries to batter down your bathroom door too, but in most cases its over kill, dowels are far more than sufficient as reenforcement with a good cope and stick or tongue and groove stub tenon joint. I've made a bunch with just a hand held self centering jig at home, I use a slot mortiser now. If you are more comfortable with loose tenons or traditional tenons no shame there, but it adds time with little benefit IMO for interior work.

On the question of does this make economic sense? You are a smart guy, there are only so many hours in the day, how you spend them is your choice. I encourage you to make one test door to work out the process, track the hours closely, you will gain some economy of scale as your batch size increases to your shops optimum level, see where it goes. Building a custom home is a big project, you could choose to GC the thing and spend 80 hours per week chasing subs and getting inspections...and reinspections.......you could build the kitchen, the furniture, make the floors (God save you but people do it). There is something very rewarding to a wood worker to live in a home where they can look at part of it and say I made that...its hard to put a value on that sort of thing. But for the doors you can clearly get a price, so I'd also draw them up and shop them around to get a clear understanding of what they would cost you to have made. At least you can then get a clear and educated sense of where the balance lies in the equation.