# Can I Install A Wet Beam Mantle And Let It Dry?



## Automaton25 (Jul 8, 2019)

Hello Everyone,

I am replacing my mantle but the replacement beam is still somewhat wet (moisture reader shows about 48% at the heart. and 15-20% on the perimeter. Obviously the beam needs to dry before I stain, poly, etc. can I install it with the current moisture content and let it dry in my house over the summer and work on it in late fall? I plan to recess steel L brackets into the mantle and screw/bolt the beam to them and to the wall. Will doing this cause further issues as the wood dries? Warping? Cracking? loosening of screws/bolts? Any likely complications?

The beam is 6×12x80 and Douglas Fir. Moisture content was taken at the heart after about two feet were cut off the end.


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## Phil32 (Aug 31, 2018)

Whatever happens to the mantle after installing will be determined by stresses in the wood rather than the brackets you use to mount it. From what you have described you have done everything in your power to limit the checking & warping. Now you have to let nature take its course.


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## Bonka (Apr 13, 2012)

Wood is gonna do what wood is gonna do.


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## Automaton25 (Jul 8, 2019)

> Whatever happens to the mantle after installing will be determined by stresses in the wood rather than the brackets you use to mount it. From what you have described you have done everything in your power to limit the checking & warping. Now you have to let nature take its course.
> 
> - Phil32


I understand it will warp regardless of the stresses and planets and moons align. My bigger concern is if print hardware on the beam and limiting it's ability to shrink as a whole unit will increase odds of deep checking, waarping, etc.

Also, is it likely to still warp and twist at this level of dryness, or is most of that done at 50% moisture?


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## avsmusic1 (Jul 10, 2016)

If the middle is that high i believe you still have chances of meaningful warp, twist, and cracking/checking. Doesn't mean it will happen but I certainly could - especially if it's a slice w/ the pith


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## kelvancra (May 4, 2010)

I had to rework a mantle once. The twist, from left to right, totaled about two inches. I covered it in 1/8" door skin using a series of shims under the skin- one set on the top left, the other on the bottom right.

Said another way, yeah, it may get wild

or

it may not.

My money is on at least a little, but at, say 20%, it's going to become art. Of course, whether it's flat or quartersawn will affect the warp and wane.


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## Automaton25 (Jul 8, 2019)

Here's a picture of the fresh cut end of the beam if it helps at all


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## Tony_S (Dec 16, 2009)

Douglas Fir is a pretty stable wood, especially with the heavy dimensions you have. None the less, as you already seem to know, it's gonna do what it's gonna do. 
If you bolt/screw it tightly to the front and back of the bracket, it'll more than likely crack even worse as it shrinks. Just bolt/screw near the center and let it do it's thing.


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## Automaton25 (Jul 8, 2019)

> Douglas Fir is a pretty stable wood, especially with the heavy dimensions you have. None the less, as you already seem to know, it s gonna do what it s gonna do.
> If you bolt/screw it tightly to the front and back of the bracket, it ll more than likely crack even worse as it shrinks. Just bolt/screw near the center and let it do it s thing.
> 
> - Tony_S


Thank you, sounds like I should be okay. I got some 1/4 inch thick 10×10x1.25 steel l brackets. Hopefully I can get it up this weekend


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## bondogaposis (Dec 18, 2011)

> Whatever happens to the mantle after installing will be determined by stresses in the wood rather than the brackets you use to mount it. From what you have described you have done everything in your power to limit the checking & warping. Now you have to let nature take its course.
> 
> - Phil32
> I understand it will warp regardless of the stresses and planets and moons align. My bigger concern is if print hardware on the beam and limiting it s ability to shrink as a whole unit will increase odds of deep checking, waarping, etc.
> ...


Yes, it will increase the odds of checking and splitting. The wood is going to shrink, it has to. If you confine it by attaching it to something immovable like a steel bracket it will force it to crack. At 50% moisture content the wood has barely begun shrinking.


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## kelvancra (May 4, 2010)

We have many homes and commercial buildings with huge fir beams that have huge splits and cracks in them. It should be kept in mind, you can be all but guaranteed they were installed with a moisture content of around 12% or less.

So, yes, fir can be stable, but no more so than other wood when it's half moisture or near it.

A lot of decks are built with fir. Those were, usually, at the 12% or less moisture content too. Had they been built with wet treated wood, you'd be walking on their edges, on hot summer in.



> Douglas Fir is a pretty stable wood, especially with the heavy dimensions you have. None the less, as you already seem to know, it s gonna do what it s gonna do.
> If you bolt/screw it tightly to the front and back of the bracket, it ll more than likely crack even worse as it shrinks. Just bolt/screw near the center and let it do it s thing.
> 
> - Tony_S


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## Automaton25 (Jul 8, 2019)

For anyone interested, here is a picture of the beam drying indoors!


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## Foghorn (Jan 30, 2020)

Nice. Looks like no attachment need from where I sit.


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## Automaton25 (Jul 8, 2019)

> Nice. Looks like no attachment need from where I sit.
> 
> - Foghorn


It's actually sitting on 4 steel L brackets. I used a router to cut channels in the bottom and back so they're recessed and barely visible


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## Foghorn (Jan 30, 2020)

> Nice. Looks like no attachment need from where I sit.
> 
> - Foghorn
> 
> ...


I only say that as I had a similar slab, albeit Western red cedar way back when and four houses ago that sat firmly on top of the brick mantle. I'd have to be doing a dance on top to get it to move, ha!


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## avsmusic1 (Jul 10, 2016)

id give it a while before running the wood stove - that'll bake moisture out of that slab too fast and just increase the likelihood of issues


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## Automaton25 (Jul 8, 2019)

> id give it a while before running the wood stove - that ll bake moisture out of that slab too fast and just increase the likelihood of issues
> 
> - avsmusic1


We are done with fires for the season, next one will be in late September or October, hopefully the beam will be dry enough to finish then.

Any recommendations for a finish? I was thinking about using General Finishes Enduro semi gloss. Will this hold up to the heat from the wood stove okay? Or is there something better to use?


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