Alder panel size - how big is too big ?

[hank dekeyser]

I feel kinda goofy asking this. ANy one have experience w/ making BIG raised panels from Alder ? IF I give her what she wants the panel will be about 38" wide by 42" tall. I say Woaaah thats too flippin huge honey. it's gonna twist all over. The panels will literally be end panels on an armoire style pantry, fastened to the wall and the "doors"/ panels will be screwd through the 3/4" carcass (faceless cabinets, full overlay Blum hinges) If I "HAVE TO" go this big I'm thinking either screw into the panel itself only, OR the rail & stile of the panel only ?? (I might get lucky and it won't move too much ?) I've searched around for awhile and havent come up w/ much info on Alders stability properties- Yes I know that is a HUGE panel - trying to convince her to split it in half -

Thanks

[J.R. Rutter]

http://www.woodbin.com/calcs/shrinkulator.htm

Plug in your humidity swing and see what happens...

[hank dekeyser]

SWEEET - Lots of good stuff there. Thanks JR - I'm still hoping someone out there has some first hand experience w/ Alder ?? I'm thinking the all knots are gonna raise heck as well ? After gluing up all the smaller panels, I'm thinking these giants are gonna be a PITA.

After giving this some more thought- I may have posed the wrong question ? Yes I realize the larger panels will shrink and expand exponentially according to size, what I reaaly want to know is if (knotty) Alder will present a problem of wanting to distort/ warp / twist, etc. especially in a panel of this size ? I've done some smaller (18 x 30) panels in knotty pine (pallet lumber) and the doors twist and warp with the seasons. The side panels however remain quite stable.

Anybody ??

[Jamie Buxton]

http://www.woodbin.com/calcs/shrinkulator.htm

Plug in your humidity swing and see what happens...

How would you derive what your humidity swing is? You can't just go get data from NOAA or somebody. That's the exterior humidity swing, and what counts is the relative humidity swing of the interior of the home, right?

[hank dekeyser]

That's what I would assume. If you have a/c and a humidity control on the HVAC system it "should" remain constant ? I have a digital barometer in the house, and summer it's near 55% and 35% in winter. is what it is. I just noticed on the Knotty pine armoire I did a few years back that the panel width stays pretty constant and the length moves more. seems backwards from what it should be ?

[J.R. Rutter]

Thanks JR - I'm still hoping someone out there has some first hand experience w/ Alder ?? I'm thinking the all knots are gonna raise heck as well ? What I really want to know is if (knotty) Alder will present a problem of wanting to distort/ warp / twist, etc. especially in a panel of this size ?

I do a lot of alder doors - clear and knotty. It is actually pretty stable compared to a lot of other woods if you don't try to use twisty boards to begin with. The largest we have done was probably a set of double panel pantry doors about 30 x 80 ea. I've seen those doors a few times since and they only seem to twist about 1/8' to 1/4" in the worst corner where they come together. I did the frames out of 5/4 and let them rest a day between rough and final milling. In general though, you need to plan on supporting/attaching large panels like that. If they are just hanging in space, they will distort. Alder does not have the strength or hardness to cause racking if panels are secured, as long as shrinkage and expansion are accounted for.


How would you derive what your humidity swing is? You can't just go get data from NOAA or somebody. That's the exterior humidity swing, and what counts is the relative humidity swing of the interior of the home, right?

I have a humidity/temperature gauge in my shop (which, along with a wood EMC as a function of temp and RH graph, is a great tool for estimating EMC). Here in the Northwest, we see swings in the shop from roughly 60% RH in summer down to 30% or less in winter. The point is to have a rough idea of the swing in your area. Here is a link to the chart that hangs in my office:
http://books.google.com/books?id=5HBH2ibu-ZwC&pg=PA113&lpg=PA113&dq=wood+emc+temperature+rh+graph&source=bl&ots=clTNdDviAg&sig=CkcsfJNHsEGCFvPwgQPRPOl1SGg&hl=en&ei=z4NNTeeiGoSasAO14pWSCg&sa=X&oi=book_result&ct=result&resnum=2&sqi=2&ved=0CBoQ6AEwAQ#v=onepage&q=wood%20emc%20temperature%20rh%20graph&f=false

[George Bregar]

I have 10-12 knotty alder three panel doors at my lake home in Northern WI...where humidity swings are pretty extreme summer to winter. Very humid summers and very dry in the winter. Top panel is a little smaller to what you are doing...but all are fine.

181368

[hank dekeyser]

I have 10-12 knotty alder three panel doors at my lake home in Northern WI...where humidity swings are pretty extreme summer to winter. Very humid summers and very dry in the winter. Top panel is a little smaller to what you are doing...but all are fine.

181368

George, being from Southern Door Co area I know what you mean about the humidity swings, I'm less than 2 miles from the Bay. I appreciate the shared experiences. JR Thanks for the links as well. I'll be putting that book on my shopping list.

As much as I dread the glue-up on these panels I'll bite the bullet and see how i tgoes, worst case I cut them in half.

I just wish LOML would quit reading all them darn magazines w/ all the ultra high end kitchens and stuff in them. "Oooooh honey , look at this, That's what I want" I'll be glad when this build is done and I can get back to some bowl turning.

[George Bregar]

George, being from Southern Door Co area I know what you mean about the humidity swings, I'm less than 2 miles from the Bay. I appreciate the shared experiences. JR Thanks for the links as well. I'll be putting that book on my shopping list.

As much as I dread the glue-up on these panels I'll bite the bullet and see how i tgoes, worst case I cut them in half.

I just wish LOML would quit reading all them darn magazines w/ all the ultra high end kitchens and stuff in them. "Oooooh honey , look at this, That's what I want" I'll be glad when this build is done and I can get back to some bowl turning. My lumber supplier sells alder plywood...if you are going flat panel you could go that route. They are in Hartford (Kettle Moraine Hardwoods).

[Jamie Buxton]

....I have a humidity/temperature gauge in my shop (which, along with a wood EMC as a function of temp and RH graph, is a great tool for estimating EMC). Here in the Northwest, we see swings in the shop from roughly 60% RH in summer down to 30% or less in winter. The point is to have a rough idea of the swing in your area. ....

So for people who haven't instrumented their homes and waited a year to gather the indoor humidity swing, do you know of any other way to get it?

[hank dekeyser]

Jamie, Being from California, I can't see how you would have much of a humidity difference ? MAybe check w/ the library or one of the University "outreach" programs ? Check the relative humidity for your area throughout the seasons and it should at least give you a rough idea what the humidity swing is in your area.