Powder Post

[TENdriver]

Okay, I've been laminating SYP construction timber for my Old Salem workbench but I was interested in getting a nice hardwood beam for a bench top. Found a lumber dealer an hour away that had some reasonable pricing for heavy stock that wasn't FAS. Unfortunately, finding a bench top was mostly a bust.

Then I found some nice "old growth" red oak that I wanted to use in some leg stock for Peter Follansbee type joint stools. That wood was looking great until I flipped it over and I've never seen so much powder post.

I had already pulled some other red oak and hard maple turning squares which I bought. All of that wood looks very clean and no issues spotted. I was going to hit it with a jack plane and check closely for damage and then throw the stock into the oven but first I need to mull over messing with it at this point.

How easy (or how hard) is it to sterilize this wood at home? It's laying in the driveway for now.

 

[CrealBilly]

You may want to try and do a search - PPB have been discussed many a time here.

Here's one --->http://www.ncwoodworker.net/forums/showthread.php?p=540021

 

[TENdriver]

I read through some of those post but I was still wondering if I could take these 2" x 2" turning spindles up to a temp in the kitchen oven and 100% kill everything. Otherwise I'll leave everything at the curb.

Also I wondered if I could have eggs in the car or dropped onto other surfaces

I probably should mention there was zero indication of active PPB on the stock I bought. I only saw it on some other stock.

 

[ScottM]

A few weeks in your attic during July should do the trick. To be safe make it 4 weeks.

 

[Barry W]

This article from NCSU may help: here.

 

[Richo B]

At my work if I find something with active PPB I bag it and freeze it for 14 days straight. But your wood may be larger than can fit in a freezer. I have one of those large sized freezers that people use to freeze fish and deer meat. Mine is large enough to put a side chair in. Freezing does work but may not be the answer. Another thing I can do if the object is too large for the freezer is to bag it and make sure the bag is sealed and leave it that way for several weeks, checking occasionally to see if there is any additional activity. That might be an option.

 

[chris_goris]

From what I read, you only need to get the core of the wood to 130F and keep it there for 72 hours.

 

[TENdriver]

At this point I see no evidence of PPB on any of the wood I bought.

I was wondering if I could heat the wood at a higher temperature for a short period.

Also wondering if eggs could be on surfaces

 

[scsmith42]

Regarding PPB, yes eggs can be on the surface.

The only 100% effective way to sterilize lumber (per industry standard) is to heat it until the core of the lumber reaches 133F for a period of 30 minutes or longer. Lumber shipped internationally must be sterilized at a higher temp, but in the USA 133F is the standard.

Heating lumber is like baking a chicken - it takes a while for the heat to work it's way into the core of the lumber. Somewhere I have a chart that lists the time it takes per inch of wood to penetrate, but quite frankly it's been a while since I've seen it and I'm not sure where it is.

For 2" lumber, if you put it in an oven at 145F the core should exceed 133F within 3 hours. If you want to be cautious, give it 8 hours.

If you put it in an oven at 200F, you need to be careful that the higher temperatures do not overdry the surface of the lumber, causing it to check or splinter when you try to work with it. In a kiln environment, we have to carefully match the RH% with the temp in order to prevent excessive brittleness from developing on the outer portion of the lumber.

FWW had an article about a simple home sterilization chamber that you can build using a space heater and foil covered foam board. I can't post it on the forum for copyright reasons, but if you send me your e-mail address I'll be happy to send you a copy of it.

Scott

 

[TENdriver]

Scott, For that article, I have FWW for 1975-2011. Is it in that range?

Also, I had seen some other lumber that I was interested in but not sure if I should just avoid that lumberyard entirely. The only activity that I noticed (and it was very heavy) was isolated to a bin of red oak.

Again, none of the material I took shows any indications so I'm not sure how concerned I need to be.

 

[Jeff]

FWW had an article about a simple home sterilization chamber that you can build using a space heater and foil covered foam board. I can't post it on the forum for copyright reasons, but if you send me your e-mail address I'll be happy to send you a copy of it.

We had a similar discussion several months ago and the OP reported that it got to and held the desired temperatures which Scott recommended.

http://www.ncwoodworker.net/forums/showthread.php?t=58639

The sterilization chamber is here: FWW #202, November, 2008 by Christain Becksvoort.

 

[CrealBilly]

Well you could just ship your lumber you want to sterilize to northern India where it's 123.8 degrees. Let it sit in a container for a few days then ship it back to you ---> http://m.timesofindia.com/city/jaip...-says-Saurabh-Shukla/articleshow/52335266.cms

 

[TENdriver]

Okay, first batch of oak squares are in the oven. Shooting for 3 1/2 to 4 hours of bake time. Unfortunately, my digital kitchen oven will only go down to 170 degrees so we'll see if that causes any issue. The stock is 24" long and I could get by at 19" to 20" so we'll see what comes out in a few hours.

Too bad the legs aren't already milled and ready to use. The tenons will be plenty dry after a few hours of oven time.