Machining rough wood for outdoor project?

[Ken Platt]

Folks - just wondering what others do in the situation of building an outdoor biggish project, in this case a simple pergola.

The wood is rough-cut white cedar, and is somewhat variable in dimensions. It's all supposed to be 4x4, but the widths I've measured vary from 3 7/8 to 4 1/4, sometimes in the same piece depending on which side and where on the length I measure. And, of course, the pieces while reasonably straight have some bow/crook to them. I think I avoided getting any with twist.

The posts and beams are, respectively, 8' and 10' long, so jointing them even on my 12" jointer isn't a trivial task, at least for me.

So...would you try to joint/plane as usual? If not, what would you do (if anything) to smooth the rough surface? Regular sanding, a trip through the drum sander (little Jet 10/20, I'd have to be careful with this length pieces), light planer pass?

Here is a picture of what I'm making, pretty much.

315513

I was going to add some 3/4 inch pieces on the bottom 2' of the posts to make it look as though there was a base to the posts, like in this. I suppose that'd be harder if I don't machine them.:315514.

I appreciate folks thoughts.

Ken

[Jerry Miner]

The construction company I work for has built a lot of pergolas and arbors. Sometimes we use the material in its rough state, in which case we lightly sand the "whiskers" off and round-over the corners. Some adjustments have to be made to accommodate varying dimensions, but it's not usually a big deal--- 3 3/4" looks a lot like 4" or even 4 1/4"

If you want all consistent dimensions, you will have to re-mill. (Note that if you are going to stain the wood, a rough surface will take and hold the stain better and longer than a smooth surface.)

If you wrap the bases, be sure to leave a little room for the posts to swell and shrink---they will! Bases and caps can be custom-cut to fit individual posts if the dimensions are significantly different. Again, no one will see 1/4" difference from one post to the next.


It's a pergola, not furniture. You want pretty-straight pieces, but perfectly-straight isn't necessary. You risk milling down to unacceptably small dimensions if you insist on getting everything dead straight. The cedar we buy tends to be pretty decent right off the saw, so we generally plane only, but some light work on the jointer is possible (or a little work with a hand-held power plane--- sometimes easier to take the tool to the work). HTH.

[jack forsberg]

i would joint it if you want fine work just get a helper and an out board stand like i did here,


https://www.youtube.com/watch?v=Jcrg4K9pPFE

[Reinis Kanders]

Those bottom posts could eventually trap lot of moisture.
Just make sure to always use the same reference faces when you do your marking for joints.

[Allan Speers]

You might JUST get away with using a 10-1/4" circular saw, with a reference straight-edge.
A 16" CS on a track would of course be ideal, but that's quite an investment for a one-time job.


Another option would be to use a fairly large band saw with a large table & wide blade, with infeed / outfeed support, and the fence on the outside & the table angled, so that the stock can't move away from the blade. (And maybe a friend to help.)


And finally, using a hand jointer is easier than your think, especially on something soft like Cedar. (Make sure to use winding sticks so as to not get any twist.) Thousands of Japanese & Chinese temples were built this way, and they came out just fine.