Question regarding interior door construction

[George Gyulatyan]

In all of the interior stile and rail door constructions that I've seen, during the construction process the stiles are usually left proud of the rails at the top and the bottom of the doors.

What is the purpose of doing it this way? Why not cut the stiles to size from the beginning?

[Dave Normand]

They are left proud to allow extra length for squaring the rails if required. In a related note, if you need to "rack" the door one way or the other, it allows you to have a surface to "persuade" the door with a hammer and not damage an area that will be part of the finished door. When I worked in a custom mill shop (17 years before starting my own) we would use a door clamp to pull everything tight and square, but still needed to manipulate some what. I suppose you could eliminate the extra length, but they provide a quick and easy way to square. Additionally, in a production setting, the rough mill pulls the material over-sized and the cutting of stiles to length is an added step that can be combined with the trimming of the door to size once assembled.

D.P.N

[Larry Edgerton]

Ditto what Dave said, and addition to that I leave my top and bottom rails 1/4" wider than I want and trim all at one time after they have set for a few days out of the clamps.

Just habit I suppose, but I don't have to worry about those two surfaces when I move them around. I always install the doors I make so no worries.

Larry

[Stephen Cherry]

They are left proud to allow extra length for squaring the rails if required. In a related note, if you need to "rack" the door one way or the other, it allows you to have a surface to "persuade" the door with a hammer and not damage an area that will be part of the finished door. When I worked in a custom mill shop (17 years before starting my own) we would use a door clamp to pull everything tight and square, but still needed to manipulate some what. I suppose you could eliminate the extra length, but they provide a quick and easy way to square. Additionally, in a production setting, the rough mill pulls the material over-sized and the cutting of stiles to length is an added step that can be combined with the trimming of the door to size once assembled.

D.P.N

Great first post Dave!

[George Gyulatyan]

Thanks for the replies guys. I am very new to woodworking in general so I have many questions. Thanks to you and everyone on this site, I am gaining quite a bit of knowledge, and hopefully in the future, I will be able to provide helpful information more rather than keep asking for it :)

[Kevin Jenness]

The extra length also allows for disassembly with a mallet or reversed clamp after dry clamping or in case something goes wrong during glueup.

[Peter Quinn]

Those little bits of extra stile length are called 'horns', and I for one skip them. I feel its really a very old school throw back to the pre-machine era which has outlived its relevance. I've heard all the explanations for why they are there, and lots of convincing arguments for avoiding them. Its one more thing you have to account for when placing your joinery, i.e. another chance to screw it up. "Did I put the mortises or dowels in the right place, or are they going to land on the horns? Will the door end up the correct height? How long are those horns? Why do I want to add 6"-8" more material that must be flattened on an all ready long stile that I must then struggle to joint?" Having made a good number of doors at work, I can tell you that finding flat 8/4 stile material in some species can be challenging, and the closer to final length you start the better. If your doors are that out of square after gluing you need extra rail width too for trimming, so the horns are basically moot IMO. Just add 1/4" in every direction and be done with it. If your doors are way out of square, trimming them is going to start changing the flats which looks terrible, in that case you really need a new door, not horns.

I have never had to smack a door around hard enough to damage the end grain of a stile with a dead blow, and generally skewing the clamps slightly can correct the situation more easily in any event. The few factory settings I have seen used a square press clamp that pretty much requires all parts cut to length, so no horns there either. And the CNC up cut lines that cut parts to length move so fast its hardly an extra step. Easier to glue the doors up square and to exact size than go back and fudge them later. WIth the horns its actually very difficult to check for square as your outside measurements are now obscured. So you can make pencil marks, but that is fraught with potential for inaccuracy, times 4, times the number of doors you are making. You will have to avoid dropping the door on the floor or hitting it with a fork lift on its corners, but to me that seems more manageable than the alternatives.

So, not every door maker believes in horns, and if you question their validity or usefulness, you are not alone.

[Rob Fisher]

My understanding of the extra length is to prevent blow out when mortising by hand, meaning with a chisel and a mallet. With machine work I can see where they could be mostly eliminated.

[Joe Calhoon]

I agree with Peter. I think leaving horns is an outdated construction method. We build all doors, windows and frames right to size, width and length. Its also a question of how accurate your machinery and layout are. For sure if mortising by hand it would be a good idea. A few years back when using loose tenon construction and not having a frame press we sized doors 1/4" over and trimed to length after assembly. This can turn into a lot of work when large quantities or heavy doors are involved.

Joe

[Dave Normand]

I agree with Peter and Joe, modern production techniques do make this point moot, but I assume most woodworking related questions here are for practical application, not production line setups.

Mill work shops here produce a lot of replacement doors and sash for the older homes in and around New Orleans. These guys are not running Weinig molders to produce the sticking profiles or computer controlled doweling. If they are well equipped, they have a sticker and single end tenoner for producing door parts. They hand grind knives to match profiles for both the cope and stick. These tools that are over 60 years old and older manual technology will not produce CNC accuracy from start to finish of cut 100% of the time, no matter how much effort is put into setup and material preparation. The horns can provide a start and stopping tolerance for any snipe that may be produced when feeding the material through the machine, thus avoiding this profile inconsistency from ending up in the cope joint. I would think this process would also be an advantage for someone using a router table or a shaper.

I have and use a J.A Fay sticker (not Fay & Egan, that's how old it is) and a Greenlee 533 tenon Machine at home in my recreational shop. I can not imagine running the stiles without some additional length, but this is recreational. When I leave for work in the morning and go to my business I treat doors like I treat the dovetailed drawer boxes I use on our commercial casework.... I buy them from a company that specializes in these items and uses dedicated equipment.

D.P.N