I'm just wondering, if you've got very dusty wood(timbers) that you want to plane, would it be better to power wash them first, or just blow them off with compressed air? Would power washing just drive the dirt into the wood or would it remove most of it? I want to keep the knives sharper longer if possible.
I deal with this a lot. Power washing is best and gets the boards squeaky clean. if you don't want that hassle, you can use compressed air, but you need to brush them before and while you're blowing them off. I live on the south side of a gravel road and the wind is often out of the north. ::)
Think it would depend on what the dust is.... house dust, vs. field dust, vs. limestone road dust, or ?? Some more abrasive than others, and I think I'd vacuum off the dust before either water pressure or compressed air that could just drive the dust into the pores.
But that'd just be my approach... ;)
blow them off with air and plane em.dust wont bother knives much, its sand and rocks that cause more problems.
If you want them clean wash them.
I pulled some spalted alder out of the barn the other day and it was covered with grit. Air and brush left it gritty, a little soap and water made it squeaky clean. Planner had fresh knives and customer wanted to keep them sharp.
These boards had air dried in the barn for several years so the cell moisture is gone and water is free cell and will evaporate quickly under normal conditions.
i have customers washing the sawdust off Hardwoods as it comes off the mill
How soon can you plane them after washing? I wouldn't figure you'd want to get to much water on them to soon before planing, but don't know.
Allan
I bet an hour or so in the sun/wind would suffice. A little bit of moisture on the surface would actually aid in planing and reduce tearout. Lots of guys planing curly maple swear that wiping the surface of the board with a wet rag a couple minutes before planing helps with tearout. Of course you don't want to be spraying water all over the iron innards of your planer either. - Ryan
No, they'd have plenty of time to dry before planing. I've got a lot of them and I'd have to check for nails/staples too before pressure washing. The timbers don't have much metal(relative to typical barn beams), but still have to make sure they are free of any before using any metal tools or blades on them. They were part of an old factory building.
With the way a planer cuts, it really doesn't matter what is on the top surface of the board the blades don't hit it first anyway. The blades rotate into end infeed end of the board and up out of the meat of the board to the top surface. The blades do not cut down into the surface of the board. Don't get me wrong, I would want to send a sand cover board into my planer, but I would brush it off with a hand brush.