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I’m making window screen frames for a customer who’s made a few himself from kiln dried 2×4 framing lumber, ripped to size.
The frames will simply be glued and screwed butt joints, about 7/8″ thick by 1 3/4″ wide, except for the bottom rails, which will be 2
3/4″.
I’m considering alder, which I can get for $1.01/bf. This is still more than the 2×4’s, but I assume the alder should be better. I think
he’ll go for this price, but not for anything more. Fir and pine are more than this in 1x material.
I understand it glues up and paints very well, but don’t know if it will be alright for exterior use. Wood mag’s “wood profiles” state
that you should “always use it indoors; the wood isn’t durable”. But, the lumber company people say it should be fine as long as its
painted. The customer will be using oil based paint. Any insights would be appreciated.
Thanks, Jeff
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Jeff - one of the things I am learning on this site is that HOW you build is often influenced by WHERE you build. Not sure where you are but here in western WA we get a lot of wood movement due to seasonal moisture changes. There is no way I would use Alder to build screens here.
First - the money you think you will save in materials, you will not save. Alder seems to me to have "a mind of it's own". When I rip it, it either pinches or curls away from the blade, so you will waste a lot of material staightening your stock.. Even if you did manage to get a straight board to work with, I really question how stable it would be later when exposed to climatic changes.
I would use fir. More specifically vertical grain fir. Since the grain is perpendicular to the face of the board it swells and contracts in a fairly uniform way. This means it is less suseptible to twisting which can cause joinery failure over time. You can probably pick through a pile of fir 2x4s and find what you need.
Now someone else will probably post, singing the praises of their favorite wood, but have you ever noticed how many window sash and exterior
doors are made with VG Fir?
Oh yeh, one other thing, I would use at least a half lap - if not a mortise and tennon joint with a 2 part exterior resin glue. Not that hard to do and FAR stronger that butt joints and screws. good luck - yb
*Jeffditto for Y.B.'s last paragraph, stretching screen will be pretty hard on those "mickey" butt joints. . . don't know anything about Alder.-pm
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Bob and Patrick, thanks for your input. I'm a bit surprised about the difficulty in working with Alder, as it is supposedly used in cabinet making. I'm in the southwest, so there aren't the extreme seasonal changes of the northwest, but... I wanted to use Fir all along, but the price seemed prohibitive. I'll work up the actual cost and perhaps overall it won't be.
Regarding the joinery, I'm basically following what the customer has done previously. However, i'm not clear as to why a good glued AND screwed butt joint, won't be similar to pocket hole joinery, which i understand is actually quite strong. As the screw heads on the edges of the frames won't be visible once the screens are installed, it didn't seem like it mattered much in this application.
My main concern was the decay resistance of Alder, but your other input is much appreciated.
Thanks,
Jeff S.
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Why not redwood? It works easily, paints nice, has good weather resistance, and B grade is alot cheaper than clear fir or pine these days.
*OK, you're asking some good questions here, and bear in mind, my thinking might by antiquated, but here goes...Alder is stable in cabinets because it's glued/screwed/nailed to boxes that are stable. And most cabinets I have worked on were for interior use, not sujected to as harsh moisture fluctuations as any outdoor application. You ever see an Alder tree? Do you have them down there? they lean, and twist, and grow very fast reaching for light the first 30 years. The grain fibers are similarly twisted and "leaning" so that as you mill it, it wants spring back to it's original shape - thus the old carpenters adage "from crooked trees you get crooked lumber". Now once you take the time to staighten it, it might be OK, but I don't trust it.As for the joinery - I have always learned that gluing end grain is a chancey proposition at best. So then you are relying on the screws. My personal experience tells me that relying on screws outdoors is dicey because as the wood swells and contracts with seasonal movement these screw "work" loose. Their threads lose their grip. Maybe you could use brass screws and epoxy, but if you want a professional job (you want to be thought of as a pro, right?) you can use mortise and tennon joinery in the same ammount of time it will take you to explain to them why the butt jointed ones only lasted 15 years. Houses should be built to last for generations, to be passed down as part of the estate, try to get in the habit of thinking 100 years when you build something, it will raise your standards. - yb
*...and I agree with Mike, below, redwood might make a good choice, will hold paint WAY better than Fir and has nice straight grain. - yb
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I usually use redwood here in Wisconsin. I can get nice straight-grained 2x4s for a reasonable price by picking through the pile. Stable, durable, light, glues well. See if you can find some polyurethane glue (Excel, Gorilla Glue, Home Depot even has some from Elmers or?). I have used it quite a bit in exterior trim and deck work (with treated pine!) and it is amazing stuff. Alder is very susceptible to rot unless you soak it in water repellent/preservative before painting but you are bound to end up making them again. I have had great success with bisquit joints and the poly glue, though the half-lap is the strongest. Your customer has to pay for making them right or its not worth your time for him to be complaining about how YOUR storms are falling apart after he paid good money...
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I'm making window screen frames for a customer who's made a few himself from kiln dried 2x4 framing lumber, ripped to size.
The frames will simply be glued and screwed butt joints, about 7/8" thick by 1 3/4" wide, except for the bottom rails, which will be 2
3/4".
I'm considering alder, which I can get for $1.01/bf. This is still more than the 2x4's, but I assume the alder should be better. I think
he'll go for this price, but not for anything more. Fir and pine are more than this in 1x material.
I understand it glues up and paints very well, but don't know if it will be alright for exterior use. Wood mag's "wood profiles" state
that you should "always use it indoors; the wood isn't durable". But, the lumber company people say it should be fine as long as its
painted. The customer will be using oil based paint. Any insights would be appreciated.
Thanks, Jeff