Help to make french doors - without twist!

[bohngy]

I’ll offer the pretext that I’m not a professional joiner…. So perhaps you’ll be kind, as you read my tale of incompetence?

As part of my home renovation, I recently made some french doors. I wanted large, uninterrupted glazing and narrow meeting stiles, so when the doors were closed the combined thickness equalled the stiles on the hinge sides… sounds simple enough.

… only they twisted like the proverbial whatnot, as much as 45mm at the ends of the stiles… far too much to correct. So into the annals of failed projects they go!
here’s some ugly pictures for you…

So, faced with making them again, I want to do it right. I thought that I might use a simple laminated construction - ripping along the thickness of the rails and stiles and flipping them 180degrees, so the grain is opposing and less likely to warp.
like this:


I was wondering what the collective opinion is? Whether the meeting stile is just too narrow (at 50mm each) and whether laminating will help? Or the third possibility is the unsorted redwood I bought was a load of rubbish and I could pony up for something more stable.

I’ve had some great help on this forum, so thanks in advance.

 

[dzj]

I understand the aesthetic reasons for 50mm stiles.
I never make them less than 110mm. A bit wide perhaps, but I've never had to re-make them.
Prior to planing, the ripped elements should rest at least 2-3 weeks.
When using laminated construction, I've always used ready made elements, mostly 3 or 4 'ply'.
I'm not sure that the 2 ply you suggest would be a guarantee of stability.

 

[johnnyb]

check all your joints as 50mm is a long way out. make it your way but use accoya.

 

[C64]

Is the door frame coplanar, straight and true? Perhaps that might be a contributor too.

 

[bohngy]

Prior to planing, the ripped elements should rest at least 2-3 weeks.

Thanks DJZ, this is something I was thinking about… long after I had put them together, I should have let them sit for a while.

I don’t fancy the work of making a 4 ply laminate for these, but I understand what you’re saying.

 

[bohngy]

check all your joints as 50mm is a long way out. make it your way but use accoya.

50mm is the thickness of the stiles, JohnnyB. It’s the stiles that have twisted around 45mm over their length, somehow. Is Accoya guaranteed to be stable against twisting and movement etc?

As these are internal doors, I didn’t think I’d need something like Accoya. I’m slightly frightened to request a quote for the cost of the stuff…

 

[bohngy]

Is the door frame coplanar, straight and true? Perhaps that might be a contributor too.

…good point! I’ll check. But I can see there‘s a massive twist, in both doors, in opposite directions!

 

[RobinBHM]

50mm is the thickness of the stiles, JohnnyB. It’s the stiles that have twisted around 45mm over their length, somehow. Is Accoya guaranteed to be stable against twisting and movement etc?

Accoya is awfully expensive.

using solid softwood is your culprit.

Id recommend using engineered softwood. You can get 48mm x 120mm made in 3 lams.

I would also check you can get a latch or lock that will actually fit a 50mm stile.

 

[johnnyb]

just as an aside try undoing one side of the frame and tapping it in or out and the reverse on the other side. it may save the day. the cause of twist isn't always obvious if the shoulders are to long or short this can cause twist. also how you cut the tenons or mortices can cause confusion. for instance my morticer makes straight mortices until I get upto 3/4 when it starts to go squint.

 

[johnnyb]

check by laying a straight edge across the joints when you've made them. it's easy to belt sand joints level but they are actually squint.

 

[johnnyb]

sorry I can see you've dominoed them. check your saw is cutting a perfect upright 90. my large domino always put dominoes on the squint. I reckon it's faulty but try it especially with long mortices.

 

[TheTiddles]

I don’t make things like this, but that doesn’t seem like much wood for a very structural thing. Are you intending to use the glass as a structural element instead of the wood? I suspect a sealed unit would pull the wood to it if you bonded the wood to it, but I’m not sure that’s done usually, more experienced people will be along soon I’m sure

 

[bohngy]

using solid softwood is your culprit.

Id recommend using engineered softwood. You can get 48mm x 120mm made in 3 lams.

I would also check you can get a latch or lock that will actually fit a 50mm stile.

thanks Robin, could you tell me where you get engineered softwood from? I’m in Wiltshire, SW and don’t think there are any suppliers that are round here… not that I know of, at least,

A door catch/lock isn’t a problem, but it’s something I didn’t think about until after I had made the doors so it’s a good shout!

 

[Fitzroy]

I was wondering the same as TheT about what glazing is going in these? It may change the outcome/advice.

 

[bohngy]

Thanks for all this, I’ll revisit the frame and have a look… and thanks Johnny, I’ll check the machine tools for square.
I made the doors a couple of months ago and the twist has been getting worse, which is why I think it’s the material at fault, rather than the joinery.

So, is a 50mm meeting stile considered madness? Or does everyone accept that their french doors will have 2x100mm stiles in the middle?

 

[bohngy]

I was wondering the same as TheT about what glazing is going in these? It may change the outcome/advice.

they’re internal doors, so the glazing is going to be a single pane of toughened glass.

 

[pgrbff]

I always machine the wood down to size slowly, leaving it slightly oversize each time and allowing it to acclimatise in the room where it will be used over a few weeks or more, especially when the cross section is small. If after 6 weeks it is still straight it should remain so after yo make up the doors. I'm not at home but I think my stiles are 60mm ish. I certainly have meeting stiles in windows, which are of course smaller at around 40mm.

 

[ChippyKlutz]

I'd certainly agree with pgrbff in saying that allowing your stuff to acclimatise fully, preferable where it will be installed, is very important. As one who's made too many twisted doors I have learnt also how vital it is to have stock that is prepped ABSOLUTELY square and twist free (at least where the joints are) as C64 alluded to above. Given the length of those stiles it would take only a tiny amount of twist over their full length to throw the frame out. I have found that if I dry assemble three parts out of the four and then sight along the two sides/lengths at either end, if those end pieces don't fully align I'm in trouble!

 

[RobinBHM]

thanks Robin, could you tell me where you get engineered softwood from? I’m in Wiltshire, SW and don’t think there are any suppliers that are round here… not that I know of, at least,

A door catch/lock isn’t a problem, but it’s something I didn’t think about until after I had made the doors so it’s a good shout!

timbmet in Oxford

http://www.timbmet.com/uk/products/range/engineered-timber/tec-door-window-stair-parts/

 

[deema]

Im surprised by the twist in the frame, firstly it would be useful to know the dimensions of the the other style and the top and bottom rails. Equally where and how many hinges you have used.
The bottom rail is slab sawn, and is cupping, you can see the top and bottom edges are raised, so the wood is drying out and wasn’t acclimatised to an internal environment. I’m guessing it came straight from a wood yard stored under shelter and into your workshop to be made into the doors.
Always endeavour to plane the same amount of each side of anything your making and leave as long as possible before doing anything in the environment it will live in. Wood that twists should not be used for rails or styles. You can get it straight, but as soon as the season / moisture levels change it will twist again.
I suspect the real culprit for your twist is the hinge style being slab cut and cupping unevenly along its length, if you were to laminate as you suggest it greatly reduces this problem. I have a number of oak internal doors that have been made using this technique. Two ply is in my experience fine. I only use three ply for curved work where I want the same meeting points for the sections on either side and it’s noy going to be painted