Working with PT Lumber

[Anthony Whitesell]

The LOML (wife) wants a fence to keep my other LOML (daughter) from running towards the road. I was looking at the price of the pre-made fencing and the pre-made fence parts. WOW!. They want $20 for a 5' piece of fence made with $15 of individual materials (ie., using pre-made/cut ballasters). Or, they want $1.19 for one 1 1/4x1 1/4 x36" ballaster, but $5.29 for a 2x4x12' that would make 8 ballasters. The only difference I see between them is that my pieces wouldn't have the rounded corners. How bad do you think PT lumber would be on a round-over router bit?

To get from here to there I would probably need to joint atleast on edge, how bad do you think PT would be to my jointer knives? As another option, I was thinking of making a jointer fence for my table saw. My thought was cheap blade, more (carbide) teeth to do the work, and would come out close enough for fence work.

Thoughts? Options?

[David G Baker]

Think cyclone fencing. Don't know the cost difference but the cyclone fence will still be standing and look good after the wood has rotted away. Most pressure treated lumber has a tendency to split and shrink. Take a look at some PT decks after they age a few years. I have cut and shaped PT lumber but it can be a breathing hazard so if you go that route wear breathing protection and when you cut into the wood you are removing some of the protected area so if the wood is going to have ground contact on the worked area you will need to add some sort of protective coating, (not sure what is used to replace the old copper naphtha or coppernal (sp?)
You can buy pre cut and shaped posts that are treated after they are worked.

[john bateman]

I think as soon as you cut those wet 2 x 4's, they're gonna bend and twist into something unusable.

[Todd Burch]

To my recollection, there is nothing abrasive in CCA that would affect your knives. I'd be more worried about my lungs than the knives.

I've cut plenty of PT wood. Some of the nicest wood I ever worked with was KDAT southern yellow pine. Wear a good mask.

[Mark Patoka]

I just got done building a couple arbors out of 2x PT lumber and didn't notice anything that would dull your knives outside the norm. Just watch out with the dust. The biggest problem is that most of the PT lumber I get from the Borg is still dripping wet so it's extra heavy and tends to clog up the bandsaw and sander. Letting it sit out in the sun a few days seemed to help somewhat.

I had a neighbor that completely fenced in his backyard with some extremely wet fencing lumber (pre-cut I think) and within a couple months many of the boards were twisted and bowed in every direction it looked terrible. He admitted he got a good deal on the wood and wasn't happy with the end result. Maybe if it had a chance to dry out first, it would've been easier to deal with all the non-straightness.

[jim carter]

todd is right pt is poisonous. they used to use arsenic but now use a copper base pesticide. wash your hands very well after handling. i dont think i would use it if you have kids that run around and could touch the fence and not know to wash their hands before eating or puutting hands in their mouth

[Mark Bolton]

todd is right pt is poisonous. they used to use arsenic but now use a copper base pesticide. wash your hands very well after handling. i dont think i would use it if you have kids that run around and could touch the fence and not know to wash their hands before eating or puutting hands in their mouth

The "poison" in treated lumber doesn't really have the exposure concerns to be worrying about children touching it per say. As has been stated there is no CCA lumber available to the retail consumer any longer. It has been replaced with "safer" alternatives like Acq, Ca, Ca-b, and so on. The pesticide portion of these treatments, just as with CCA are locked up in the wood. With CCA this was done through the chromating process. Exposure from handling is very minimal. The problem arises with long term exposure, think slivers, sawdust, leachate, and what caused the hullabaloo to begin with, idiots burning poisonous lumber to dispose of it rather than doing it properly. Burning and burrying are the main culprits as burrying leaches and burning breaks the bond established by the chromating and further causes a chemical reaction converting then arsenic to a much more carcinogenic form and delivery methog (arsine gas).

It was, and has never been, the treated wood being the problem. It has always been improper handling by the consumer which has us now paying 40% more for treated lumber and denying us access to a time proven product. We are now left with untested materials that cost more.

[sullivan mcgriff]

Remember though that once you rip the 2x4 into smaller pieces you have a long side with no treating, same with rounding over the edges.