warping kitchen shaker doors

[RogerM]

Guys - I know we've had a similar thread before but I can't find it.

I've just done a "quick and dirty" face-lift of my mum's kitchen to make it more user friendly for an 83 year old in the early stages of dementia and overall it works well. However, I made the shaker doors/drawer fronts with beech stiles/rails and mr mdf panels, and whilst they stayed flat for weeks whilst stored in a spare bedroom at home, they have started to warp now they have been hung. My best guess is that it is because mum heats her home to resemble a sauna! I've never had this problem before.

This is one of the worst examples, and I'm guessing there is no alternative other to replace them?

The drawer fronts are fine, but the wall unit doors are the ones that are suffering.

What is the most warp/twist resistant way of making a painted shaker door? I know that JFC posted a thread on this some time ago, as did "doctor bob", but I can't find them. Speed of construction is the key consideration, consistent with staying flat reliably.

Options I'm considering are :-

1. 18mm mr mdf stiles/rails with 6mm centre panel. I seem to remember that jfc recommended this in a thread, using 6mm mr mdf splines to join the corners. This had the advantage of only requiring the router table groove cutter to be set up once.

2. 12mm full size mrmdf panel with 6mm stiles/rails glued to the front.

3. 12mm birch ply full size panel with 6mm mr mdf stiles/rails glued to surface.

I'm using Blum soft close hinges with a standard 35mm recess. Is mr mdf OK to hold the screws for a standard 595mm wide door? That's the main reason I'm thinking of using 12mm birch ply. Sadly, the finished job will probably only have to last a couple of years. When the bungalow is finally sold it is likely to be bulldozed to provide a plot for a large detached house as it is a prime 3/4 acre plot with open southerly views in east Devon.

Any constructive comments gratefully received.

 

[Adam9453]

I'd go for option 2, quick, stable and nice finish for paint

 

[custard]

We've all been there Roger, and it's a credit to you that you're determined to have a second go and put it right!

Option 1 would be my choice, or instead of Beech use straight grained Poplar and take it down to final dimension in stages.

Good luck!

 

[dzj]

Or instead of a 60cm wide door, make two 30cm ones.
A smaller door will warp less and it can be usually compensated by adjustments in the hinges.

 

[Jacob]

Beech is unstable and pointless anyway if you are going to paint it.
Best is option 1 but the panel needs to float loose in the slots to allow for movement.
If you wanted a thicker panel the trad way would be to reduce it to fit the slots 6mm ish around the edges, with a bevelled "field"

 

[Racers]

I would hang fire for a couple of weeks to see if the moisture content equalises between the inside and out side and they go flat.
You have nothing to loose.

Pete

 

[blackrodd]

If that's a working kitchen, with the oven being used, it would be a good idea to design something to keep the oven heat and steam from doing this again,
Suggest, Rectify the heat and steam, have a go at steaming the door straight, And replacement by method 1
How very annoying to have such a nice kitchen re build spoilt.
Regards Rodders

 

[AJB Temple]

In that location it is tricky because any casserole or similar cooked in the oven will release a blast of very hot steam when it is opened, or dryer heat otherwise.

As it may only be for a few years I might be inclined to redesign it so that there is a piano hinge along the top with a gas lift and a latch mechanism at the bottom. and possibly brace the interior to discourage warping. Good luck. Insulate between oven and shelf.

 

[johnf]

Method 2 works for me just done some for my daughter all stayed flat

 

[monkeybiter]

Re. Jacob's comment that option 1 would need a loose floating panel, is this necessary with mdf as specified?

 

[Nelsun]

viewtopic.php?p=1008085#p1008085 Not sure if that's the one-slot-router post you were looking for. I have it bookmarked so I don't forget to try it out.

 

[petermillard]

I'm using Blum soft close hinges with a standard 35mm recess. Is mr mdf OK to hold the screws for a standard 595mm wide door?

Yes, easily.

Re. Jacob's comment that option 1 would need a loose floating panel, is this necessary with mdf as specified?

No, not with MRMDF throughout - very stable, no movement IME.

Cheers, Pete

 

[MrYorke]

Either build completely out of MR MDF. No need for a loose panel. Glue it all together and it'll be fine. Been doing this for years and never had a problem.

Poplar/tulipwood (same thing) is also nice and stable. I use a veneered panel in this instance. The panel is almost always just a fraction over 6mm thick so watch out for hat when doing your set-up. Again, all glued together is fine.

MR MDF will take longer to paint. Use a product called Zinnser Bin to seal the edges. Get an equivalent from Johnstones Decorating Centre. Couple of £ cheaper.

Fair play to you for doing this for your mum. I'm sure you have plenty on your plate with her condition. I wish you and her well as I know how painful a condition can be for loved ones. Good luck

 

[Jacob]

Re. Jacob's comment that option 1 would need a loose floating panel, is this necessary with mdf as specified?

It is if you mix materials, or wood - which move differently in different directions across/along the grain. But yes if you made it all of the same mdf you might get away with it.

 

[RogerM]

Thanks for the comments guys. Cutting stiles and rails from a sheet of either 18mm or 22mm mrmdf is going to be a lot less work than using "real wood". Looks like that is the way forward. Can't help feeling that simply gluing some stiles/rails on a 12mm door is going to create an asymmetric glue line that will invite warping.

I would hang fire for a couple of weeks to see if the moisture content equalises between the inside and out side and they go flat. You have nothing to loose. Pete

Good idea. My sister has organised the fitting of worktops and tiling this week, with a new floor covering to be laid next week.
Then we are off to Sri Lanka for 2 weeks so I think I'll leave it until we get back to see how the rest of the doors behave before deciding on how many need replacing.

In that location it is tricky because any casserole or similar cooked in the oven will release a blast of very hot steam when it is opened, or dryer heat otherwise.

As it may only be for a few years I might be inclined to redesign it so that there is a piano hinge along the top with a gas lift and a latch mechanism at the bottom. and possibly brace the interior to discourage warping. Good luck. Insulate between oven and shelf.

Yep - it's a difficult one isn't it. This alcove was the only place for an eye level oven to replace the old lowlevel one she had before. I suspect that it will not be used intensively - just the occasional batch of scones or cake. I've put in a 36mm shelf above the oven (2 layers of MFC) and the back of the oven housing is completely open and there is a 600mm x 60mm vent up behind the cupboard above to get rid of any excess heat. Also it's a decent Neff oven with a max current draw of 3kw which is well insulated internally, so I don't think it should be too much of an issue, apart from the heat released when the door is opened. I think I'll just replace with a 100% mrmdf door first to see if that resolves the problem. I still think the problem stems from the beech frames not being of the steamed variety (which I used for my own kitchen without any problem whatsoever), plus the excessive ambient temperature.