# avoid warping



## woody1401 (Dec 2, 2013)

I need to make some beams out of 1 x 2s in this configuration

I will glue and screw them and they need to be 15 feet long. Any advice on least expensive wood consistent with minimal warping and twisting?


----------



## DaninVan (Jan 1, 2012)

Is cost a concern, Woody? How durable do they need to be? Interior or exterior application?
For outside stuff, where strength isn't a big deal, I like Western Red Cedar. I always keep a few planks lying around drying, so they're ready for machining when a project pops up, but for 16" lengths you're
really limited to construction material. 1x4 SPF or D. Fir if you can find it. In 16' lengths the quality will be fairly decent in either.
For those small dimension members predrilling the screw holes may save you some grief.
Also, a slight (1/8" deep x 3/4" wide) dado in the face of the bottom member will be a huge help in assembly... it'll keep the whole shebang nice and straight with the vertical leg exactly centred...also you'll know exactly where the glue goes!


----------



## Herb Stoops (Aug 28, 2012)

woody1401 said:


> I need to make some beams out of 1 x 2s in this configuration
> 
> I will glue and screw them and they need to be 15 feet long. Any advice on least expensive wood consistent with minimal warping and twisting?


Are you going to buy the 1X2's already made or cut them to size yourself.
The thing about 1X2's is that you need straight grain knot free material and beware that if you buy 1X4's or wider, you don't know what they will do when ripped to 1 1/2". there are all kinds of internal stresses that are released. 
If I were doing it I would hand pick 1X2's from the pile, and as a last resort mill them myself.
Not sure what you are going to span /support in 15', but you will have to have intermediate support/hangers because that size will not support itself.
Not knowing what you are making, I have no idea what kind of wood you would use. 
Herb


----------



## Stick486 (Jan 4, 2013)

rip 2 by material to ¾ thickness...
look to Redwood or vertical grained fir... (VGF)
knotless cedar will be hard to come by..

by studying the ends of your selected material you'll be able to find lumber that has the tightest and most verticaled grain...
the more perpendicular (and the closer together) the grain lines are to the face the better off you will be.. it's the most stable of saw woods...


----------



## Cherryville Chuck (Sep 28, 2010)

Woody your profile doesn't say what area you are from but if you are out west then D fir, spruce, lodge pole pine, and hemlock are all possibilities.


----------



## DaninVan (Jan 1, 2012)

Stick486 said:


> rip 2 by material to ¾ thickness...
> look to Redwood or vertical grained fir... (VGF)
> knotless cedar will be hard to come by..
> 
> ...




That's a great illustration of expected warpage, Stick! That should be a 'Sticky'... :grin:


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> That's a great illustration of expected warpage, Stick! That should be a 'Sticky'... :grin:


it should...
I've asked...
here's another...


----------



## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> Woody your profile doesn't say what area you are from but if you are out west then D fir, spruce, lodge pole pine, and hemlock are all possibilities.


I believe I'd pass on the lodge pole...
VGF would be my 1st choice...


----------



## DesertRatTom (Jul 3, 2012)

What stick said, plus a dado on the side-ways stringer, plus glue, lots of glue. But I also doubt it will support itself, let alone anything set on top of it. You might get a little more strength if you use three pieces in a U configuraton, or if you put a third stringer on top, like an I beam. The crossed stresses in the three pieces of the I beam should help cancel each other out resulting in less twisting. But sagging will be your main problem, especially over time.

If it is outdoors, use waterproof glue. If outdoors, a water proof coating might be wise. 

I have a grid of 2x2s about 14 x 10 feet, on which I stretched shade cloth for an open area over a patio. There are 3 long stringers, one on each side, one in the middle. I used some existing, very twisted 2x2s under the grid that were already in place to span the bottom. Straightened them as much as possible and put one long deck screw in the middle to attach them to the middle stringer. Amazingly the twists have completely straightened out (rains and sun) over time. So depending on what you're making, attaching the T or I beam to whatever it supports may help strengthen it and keep it from twisting. 

Personally, I'd make this using shorter lengths of a harder wood and overlap the joints so they don't meet in the same place. I think you are going to have a much easier time finding sufficient material with appropriate grain if you go for shorter pieces. For the top and bottom of the I, or the cross on the T, I'd select grain that was perpendicular to the flat side. For the I or stem of the beam, I'd look for grain that was parallel to the flat surface. With the I beam construction, you could use a really good ply, which will be dimensionally stable as well as very strong. The edges in the vertical piece buried in a groove will protect it from moisture. Screws through the whole beam and into whatever the beam supports will also help prevent warping.

Whatever approach you take, Glue and screws will turn it into a solid piece. If you use a shallow dado to set the tall dimension of the I beam in place, you'll get a little more glue surface, which will help strengthen the final result. 

How, exactly will you be using this?


----------



## woody1401 (Dec 2, 2013)

Thank you all for the great and helpful info. Attached is a photo similar to the project I am making. I will replace the aluminum beams with the 1 x 2 ones I was asking about. I think the dado idea would be worth doing also. Again, thank you all.


----------



## DaninVan (Jan 1, 2012)

I've seen those before! Actually, my neighbour has a commercially made one. His cover has hanging devices that run in tracks (perpendicular to the folds) that allows them to retract the cover for more light, and for protecting it during snow etc.
Seeing what you want to do with it now, I'd strongly recommend upgrading the vertical fin to a minimum of 1x*4*...and even then I'd be worried about it sagging over time (15' span is huge).


----------



## Herb Stoops (Aug 28, 2012)

From what I see in the picture is 2X6 alum. beams w/ 1x2" or 2x2" alum. cross pieces for a trellis on top. Then there is 3/4" or 1" diam. alum tubing supporting fabric panels that are supported by aircraft cable so that they can be slid to open/closed poistion.

What exactly are you going to replace with the wood 1X2s ? The trellis ? The fabric screen supports? 

Herb


----------



## woody1401 (Dec 2, 2013)

I plan to use the wooden beams to replace the aluminum ones holding the fabric and hanging from the cables. The beams will be approx. 15 ft but the span between cables will only be 3 or 4 ft. There will be no trellis above. When the fabric is retracted only the cables and draw cords will remain overhead. The covered/uncovered area will be about 15 x 15. This is all being planed for our place in East Texas piney woods.


----------



## DaninVan (Jan 1, 2012)

What's wrong with the Aluminum ones, Woody?
As previously mentioned here, 1 x 2's aren't really up to the task for a 15' span. 2- 1 x 4's with a 1x2 sandwiched in between (all three edges flush at the top) , and a 1 x 4 ripped to 2 1/4 flat across the top would be my minimum expectation for that long a beam, carrying the fabric canopy (each one being 3' - 4' apart). Remember, it has to be able to withstand wind gusts and that canopy is sort of like a sail, even if it is horizontal.


----------

