another interior door question

[Greg Brophey]

I am buidling about 35 quarter sawn white oak 4 paneled 1 3/4" wooden 3 ply laminated interior doors and would appreciate any members' suggestions on what size dowels to use. I believe for me that this is the best way to do it, and have never used dowel joinery before. I do have a Jessem doweling jig. It is not the newest one out, but the one that has maximum hole diameter of 3/8". Not sure if this is good or not and hate to buy another jig, but if 3/8" is not good, than I can go 1/2". I doubt for me it is worth going 5/8" diameter. I can go 3/8" and just put in more. I also would like to give a little slack in the hole to the dowel and like to know what is a good overage for the dowels to be made. I usually use loose tenons for joinery but decided in this case to go with dowels. I also thought that using a long special lag-type screw going through top side style into rail and plugging the holes would add extra strength.

Door parts are solid laminated 3 ply styles and rails. I cheated on some parts and just glued in small thickness of solid wood where it will be seen, and used plywood for rest of lamination. Sides and top rails are about 4 3/4" wide. Bottom rail is 3 ply 10" wide. Middle is 8" wide. Verticals are 4 3/4" wide. Any recommendations for each joint is very appreciated on how many to what size suggested, how far apart from edge and from each other, and how long. How much loose fit, which I want to do, should be given, and best glue to use. I have enough parts for about 4 doors made right now except for panels which I plan to install after I install doors, as these are too heavy for me to install alone if all put together at one time.

Also any suggestions on where to buy the dowels would be helpful as well as the best bits to use. I normally use Fisch brad point wood bits, but again, I am looking for experienced answers from guys who do this more than me and any suggestions for ease of build would be very helpful.

[David Kumm]

5/8" dowels would be my minimum. Dowels aren't a very good method because the glue area is so small. A 5/8" dowel has less than 1/2" actual long grain glue area on the hole side. Ply stiles might increase that slightly but still not a lot for 1 3/4" doors with some weight. 1" would be better and loose tenons or traditional are a much better method if you can figure out how to do that. Dave

[mreza Salav]

I built 31 doors using 1/2"x5" dowels. I went over 900 dowels in all and my panels were 3/4" glued-in plywood as well.
I would *strongly* suggest get yourself the Festool Domino XL as your wrist will not appreciate drilling those many holes. Plus, your drill bits won't last enough (mine was drilling in solid maple).
If I was doing it all over again, for that many doors, for sure would get the Domino XL.

[Jim Becker]

If you have not already done your laminations, you can "build in" mortices at the middle rail position and either mortises or bridle joints for the top and bottom rails. This will be substantially stronger than trying to use dowels. Planning for this as part of your lamination process makes it really easy to have deep mortices/recesses that would be more of a challenge to cut "traditionally".

[Warren Lake]

based on what ive been told the center lamination should be turned sideways or quarter sawn and the outside faces should both be oriented opposite. Old guy even laid out the cores opposite all the way through. When I told him I saw a Major door company making a door of three laminations of mahogany he shook his head. simply something they would never consider, it got more comfortable when I asked about the middle being made up turned sideways or at least quarter sawn.

[John TenEyck]

If you are using cope/stick joinery or dado and stub tenons for the stiles and rails, 3/8" dowels will be fine for interior doors. All the dowels do is keep the frame from racking, the glue area of the cope/stick joinery is what keeps the frame together. IMHO, screws have no place in a door frame, especially if you plan to screw into end grain. But I don't get why you aren't going to use loose tenons if you typically do. 2" deep 1/2" tenons are more than enough for an interior door, and are easy to make with a hand held plunge router and edge guide or collet and jig.

John

[William Hodge]

Why not use motises and tenons? A hollow chisel mortiser from Grizzley costs $260., a 5/8" chisel is $60., and you could make mortise and tenon doors. You can make the tenoned rails on a table saw. I have done this with entry doors many times. Given the weight of the doors, the joints need all the mechanical help they can get.

I built dowell and epoxied wood and glass passage doors in a door shop when I first started woodworking.

[Ray Frederick]

When we were making a lot of doors out of all solid stock we would often use 3 5/8' dowels, probably 5" overall length. Then after the door was all clamped up but still in clamps we would use our self centering dowel jig and a long bit and add through dowels. Usually one on the top and 2 into the bottom rail on each side.

Doors were for exterior and interior use, they have seen over 5 years of use in several different commercial settings and have not had a single problem. Some are over a decade in service and still going strong.

Doors were solid stock per designer and owner requests. We also do the occasional LVL or ply code door, just depends on the job material and specifications.

[Warren Lake]

Wish I had learned more about doors from the old guy, he made cores like no one I know of and I dont get how they were all stacked flipped reglued and and, up to six inches thick. I do remember he said they had to last 300 years and he got whacked once for taking a short cut. At another funeral today there was a guy who learned in a different shop there as just a door and window maker, they worked in solid only. Likely better material and aged better than what we see.

Here is a door place I was into that had some very nice entry doors. Id seen their stuff at a show and it was nice quality work with high quality materials and finish the doors had looked better than a lot of furniture. Think Joe knows about this type of dowel construction, new to me. Dont know why they dont do mortise and tennon, this looks like its done on a CNC machine.

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[Greg Brophey]

Wish I had learned more about doors from the old guy, he made cores like no one I know of and I dont get how they were all stacked flipped reglued and and, up to six inches thick. I do remember he said they had to last 300 years and he got whacked once for taking a short cut. At another funeral today there was a guy who learned in a different shop there as just a door and window maker, they worked in solid only. Likely better material and aged better than what we see.

Here is a door place I was into that had some very nice entry doors. Id seen their stuff at a show and it was nice quality work with high quality materials and finish the doors had looked better than a lot of furniture. Think Joe knows about this type of dowel construction, new to me. Dont know why they dont do mortise and tennon, this looks like its done on a CNC machine.

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A picture is sometimes worth a thousand words. I like the way they did that. Any idea what size dowels those are? I too am only seeing dowel construction on custom doors at every top notch site I go to. I too wonder why they have gone this route but this is what I was getting at and that picture says it loud and clear to me. Do you have any other photos on these doors by any chance and do appreciate all the comments as one way does not serve everyone here. Please keep commenting as no one is wrong when it comes to these techniques, but this is how I learn and have learned all my life. From good teachers and craftsman. Unfortunately I can't do the cope and stick on my doors, due to shaper out of commission. And I got every shaper bit I would have needed. I will have to go All square cut. Joe, please comment on this also if you are reading this. Need your input here.

Also the poster who commented about doweling after clamping the doors? I like that to. Can you tell me if these were coped and sticked construction? I have alot of the tools but no access to them right now. All 3 phase in my garage waiting for new shop. My Northfield 16" jointer cost me what Festool wants for their XL 700! I can't go there. I am anti-Festool. This is not directed to anyone who owns them. To each his own. I am old fashioned made in the USA type of guy. Most all my tools are USA made, and most were not bought new. I think the term is "Old Arn."

My Oliver mortiser is also in there, with the shaper and everything else. I do have a loose tenon jig I built some years ago, and it works spot on with cabinets. Not sure how easy it would be with these doors though. It is extremely accurate and easy to use and I did build it for passageway door construction. I know, why didn't I get these machine shop tools in place to use? At the rate I am going, I may never get them out of the garage.

[mreza Salav]

There is nothing wrong with using dowels. I have used a lot. Also used M/T (for the french doors). All those doors are holding up absolutely fine.

Here are the three threads for my 31 passage doors:
https://sawmillcreek.org/showthread....ors&highlight=
https://sawmillcreek.org/showthread....ors&highlight=
https://sawmillcreek.org/showthread....ors&highlight=

[Greg Brophey]

There is nothing wrong with using dowels. I have used a lot. Also used M/T (for the french doors). All those doors are holding up absolutely fine.
con
Here are the three threads for my 31 passage doors:
https://sawmillcreek.org/showthread....ors&highlight=
https://sawmillcreek.org/showthread....ors&highlight=
https://sawmillcreek.org/showthread....ors&highlight=

Great job on your doors. It's alot of work even if you are building with solid one piece stock pieces. I like the French door and the glass you put it.

Anyways any pointers on easy way to do the French doors would be appreciated and what glass to use and where to get it???
Would I ever do this again? Absolutely NO. What type of doweling jig did you use? I have a Jessem old model 8300 which is nice but only goes to 3/8". I will have to get another as I will have to use 1/2" dowels for sure. Not sure which one I want to get though. My biggest issue is that I bought quarter sawn white oak when prices were low, and not alot of sawyers cut it this way anymore. The boards were all straightened out using a sled and shims, but still it was not a premium grade. This has caused me to have to glue boards together even before laminatiing them, so the work to get there is too much. However, after much messing around, I do have a track saw that produces glue line results using my regular circular saw on a saw mount and a Forrest WWII saw blade, and a 12' one piece aluminum track. I can straight line boards as narrow or thin as any dimension, depending on the length, which is not possible with many other tracksaws they sell with any precision. These are more for sheet goods than for what I needed, and am glad I bought what I did, as it works great for me for what I do, and works well. It is alot harder to straight line narrow stock on a tracksaw than you might think unless you know how to do it. Easy to do boards that are as wide as the track itself, but not easy for those narrower ones, and I am referring to glue line quality rips.

All jambs are already set. All floors are hardwood. What gap did you leave under door for hardwood floors? I have read many articles and don't want too big and don't want too small. I have central heat and air, so it does make a difference for that. By the way, I built the house too, but that is what I do. I really don't have the time to build these kinds of things inside that are custom made, but did for this one. It is my house so I figured why not give it a try.

[John TenEyck]

If you already have a jig made for routing loose tenons in doors, and you like how it works, why not use it? You are over thinking this.

John

[mreza Salav]

I have both 8300 and 8350 from Jessem and used the latter with 1/2" bushings.
I tried using a router jig to make mortises for loose tenon. Too slow, lots of work.
I made the jambs too. To set the jambs I was using a 3/4" piece of plywood that was a hair thicker than my hardwood to keep the jambs off the floor so that the flooring goes under them after. I bought the glass unit for french door from a local door supplier (they used various versions of those glass units in their doors).
I used true M/T for french doors as I felt I needed strong joints at the lower rail. The other doors had glued-in panel as well plus 16 dowels (1/2"x5") on each side of the door.

[John TenEyck]

These are 5/8" loose tenons for a set of 1-3/4" thick French doors I made.







The doors were scribed to the floor with about a 3/8" gap underneath in order to clear the carpet. They are interior doors so the glass is single pane, but tempered. I got them through http://www.wolverineglass.com/. The pattern is called "Rain". Another excellent source for tempered glass is http://www.paragontemperedglass.com/about-us.aspx. They are very competitive; they just didn't carry the pattern I wanted.

Here's a 1-3/8" pantry door with 1/2" loose tenons, only 1-1/2" deep. The panels are plywood but are not glued in. I probably should have, but for some reason I didn't. The French doors were glued up with TB II, the pantry door with plastic resin glue.






Those wire shelves are loaded with canned goods. It's been about 8 years now and all is well. The gap to the floor is about 1/2" to allow for some air circulation, or so I told myself. None of the doors are cope/stick; the stiles/rails are butt joints. It would have been better to use a stub tenon on the rails for the pantry but I didn't.

It doesn't matter if you use dowels or loose tenons as long as you have enough glued surface area. If you use cope/stick joinery the glued surface area for the loose tenons or dowels can be less. I know a guy who has built hundreds of exterior doors who swears he doesn't glue the dowels in, only the cope/stick surfaces. I'm not advocating that, only using it to point out that the glued surface area, no matter how you get there, is what's important to keeping the joints together.

As an aside, I had to chuckle, Warren, about the comment of the guy who was building doors that had to last 300 years. I'm pretty sure he'll never know. I doubt his company needs to worry about a claim either if they don't.

John