How long do you let wood acclimate in you shop?

[roger wiegand]

6 months to 40 years (so far). I seldom buy wood for a specific project, instead I buy exceptional wood whenever I find it and restock on my basics of maple, cherry, walnut, and poplar as I start to run low, buying a couple hundred bf at a time.

[Rod Sheridan]

Wondering how long you let newly accquired material acclimate to your shop before you begin machining?

Thanks

Sometimes decades

Normally a few weeks, however that's dependent upon the wood's moisture content...........Rod.

[Alan Lightstone]

Typically a week or so, though I also have some nice wood that's been here closer to a decade.

As said above - a moisture meter is your friend, and the final purpose / destination / moisture content at that destination play a role.

[Jim Becker]

Since I started doing more work for others, I get into the situation of using "new stock" more often now. Much of what I buy needs little or no time but I still most often take a conservative route and only mill shy of final, let it sit stickered to acclimate and then mill to final. As has been mentioned, my moisture meter plays a roll, too. For that locker door project I did not long ago, the 6/4 clear pine that I had to order in required a lot of coddling to "Get there" and was milled in multiple steps with stickering and air flow over almost a week and a half before I even considered using it. The meter was absolutely the guide there. Fortunately, pine gives off moisture relatively quickly.

[John TenEyck]

I've found that the worst thing I can do is to bring wood into my shop and wait a few days for it to acclimate and then start using it before it really has. I was pressed to finish a project a few years ago and bought some 6/4 maple that I needed to resaw into door panels. My mm said it was 11 -12% and my shop was 7 - 8%. After 3 days the surface was 8% so I resawed it. It cupped as soon as it came off the bandsaw. I figured it would flatten out in a couple of days. Nope. Never did. Still under pressure to fiinsh the project I bought some more of the same wood and resawed it immediately. It was 11% both inside and out when I did that. It never cupped.

So either use it immediately or wait until it's at equilibrium with your shop (the better choice by far), but using it while it's in transition is a really bad idea.

John

[Ron Citerone]

Another thought about acclimation. Seasonal issues. Here in PA, I have found taking wood from an unheated outdoor situation at the change of season is problematic. E.G. end of summer, end of Fall. I had issues with wood from sheds and unheated garages in the past.

Never had a moisture meter, but I should. I think that would solve a lot of issues.

I do believe in acclimating lumber when ever possible.

[glenn bradley]

Moisture meter. I rarely find material that won't acclimate in a few days. Another few days (or whenever the meter says so) for resawn stock. Dimensional lumber . . . 2 months or more. I live in a dry climate with mild humidity swings but, kiln dried 2 x 12's are still soaking wet.

[Warren Lake]

your shop should be 60-80 F
your shop humidity should be 30-40 percent
your hard wood should be 6.5 percent when you buy it
your soft wood should be 11 percent when you buy it

there are plus or minuses on those numbers but its not too much,

What type of moisture meters, pins that Penetrate 5/16" .

[Will Blick]

Great post Warren! Hard for some of us to keep shop at 30-40% in high humidity areas, but point well taken.
John T, what a scary story...good way to waste some good wood... I have some re saw projects coming up, I will certainly be on the look out for this...
How do you determine the moisture in the middle of a 1.5" board without cutting it?

[roger wiegand]

How do you get your shop to 30-40% humidity? We get that low (or lower!) for a couple months in mid-winter, but most of the year it's in the 40-60% range, and through the summer 50-70 with the AC on. (it's 85% outside right now) That's in Massachusetts, not what most people regard as a particularly humid environment. It would be delightful to have my shop at 30%, but I think I'd have to run a huge bank of dehumidifiers to get there. Given the typical RH in New England lumber from the yard comes in at 8-9%, consistent with a ~50% RH.

[Warren Lake]

the specs are from Gerry Metz who was a top consultant to industry.

People with shops running up to 1000 pieces wrote in to him with problems and he told them what they were doing wrong and what was causing it. He wrote for many years for Wood Magazine and he knew his stuff. Its nothing new if you are a veneer guy you have a room and its temp and humidity controlled where its all stored. If I buy wood from a pro supplier its 6.5 to 7. Agree hard to keep a shop to those numbers and ive had to work miracles from mine its not possible so I have to build according to what it is. As soon as you make a piece where you are and it goes to another place then its a whole other temp and humidity different for different places.

[Kevin Jenness]

Jerry Metz also prescribed ripping and flipping pieces no wider than 3" for panel glueups as I recall. I wouldn't take everything he espoused as gospel. His recommendation for using softwoods at 11% may be valid for exterior millwork but makes no sense to me for interior work.

[Warren Lake]

I dont do all he said, I dont do all the old guy I learned from said but for the most part I dont see stuff close to the old guys work. Raised panel one piece cathedral up mortise and tennon. Door maker seen up to 11 rips cope and stick.

i dont do the ripping and flipping as im not making 1000 pieces. Look at the application, and why, most factories are using a low grade of wood to begin with. I once emailed a wood expert who talks moisture and wood in the shop and asked him how many thousands of feet he has machined and got no answer. Wood is a dance of tension release.

Ive used 11 for exterior and 6.5 pine last supplier on interior and it felt brittle to machine compared to the exterior stuff. The 6.5 pine for me was for more wall storage cabinets I should check it and see what it is now. I moved them last night and they felt damp. I agree the 11 sounds high, I asked my supplier and it was a junior guy and non answer on the 6.5. I had an email today on my Delmhost meter and will see what they say.

[Will Blick]

Great thread !
Is there a table showing shop % RH and what wood % humidity should be for that environment?

Here in SCal, it can be 80% RH in the shop today... tomorrow the winds change direction (Santa Ana's) and the shop falls to 12% RH for several days, or even a week. Major swings. I would say 80% of the days, it averages 60% RH in my shop.

Also, if the finished project will be subjected to the same temp and RH as what its built in, the finished product should fare well, yeah?

[Kevin Jenness]

Here's a short article on the subject with a graph plotting equilibrium moisture content vs relative humidity https://www.wood-database.com/wood-articles/wood-and-moisture/.