LumberJocks

Warping on pine table

  • Advertise with us

« back to Wood & Lumber forum

Forum topic by mcg1990 posted 03-29-2015 07:28 PM 782 views 0 times favorited 18 replies Add to Favorites Watch
View mcg1990's profile

mcg1990

159 posts in 754 days


03-29-2015 07:28 PM

A few days ago I made some shelves for a customer who bought one of my very first tables about a year back. I took a look at the table (pine, 6/4 construction lumber) and was shocked at how much expansion had occurred. The table was pretty basic. 2” x 8”s running lengthways with breadboard ends at either end, fastened by pocket screws. Yeah, real complex joinery..

The breadboard ends have since expanded by about 1/4” on either end, it’s really noticeable. They love it anyway – I built it for little over cost price! – but how can I go about reducing this in the future?

It was built in a fairly humid Summer, before my shop was finished and air conditioned. So I’m guessing this has happened as a result of moving it from those conditions to inside an AC controlled house.

Would the solution be to keep a small inventory of my most common used lumber and keep it at room temperature? If so, how will I know how long is long enough?

And what if I was building a piece of furniture destined for exterior use.. How can I make sure the piece behaves through wet freezing Winters and 95 degree humid Summers?


18 replies so far

View bandit571's profile

bandit571

14555 posts in 2144 days


#1 posted 03-29-2015 07:52 PM

Not much can be done…

That said, a few tricks for the next time

IF the front edge is the “show” edge, pin the top to the breadboard edge there, no slots. Let the expansion/contractions happen to the back edge.

On the latest Pine table I made…. a small brad inti the center of each board in the top. Driven from the underside of the breadboard edge, through the tongue and on into the top, without going through the top, of course. Nails will give a little, but tend to keep things in the same general area. Yes, I did add some glue, too. Mainly in the areas of the nails. Localizes the movements abit..

Big thing is to add the same amount of finish to the bottom as was used on the top.

-- A Planer? I'M the planer, this is what I use

View Bill White's profile

Bill White

4450 posts in 3422 days


#2 posted 03-29-2015 08:17 PM

Breadboards didn’t expand. The “field” planks in the table shrank as they dried.
Acclimating the wood will help as you stated, but borg wood is really wet at first.
Bill

-- bill@magraphics.us

View mcg1990's profile

mcg1990

159 posts in 754 days


#3 posted 03-29-2015 09:07 PM

Would using a large mortise and tenon and dowelling at intervals along the width restrict movement? Or would it cause the planks to buckle as a result to the tension?

View Ghidrah's profile

Ghidrah

667 posts in 683 days


#4 posted 03-29-2015 09:12 PM

Framing lumber (Spruce) isn’t meant to be used for fine furniture. If the intent was a rustic look you certainly got it.

-- I meant to do that!

View mcg1990's profile

mcg1990

159 posts in 754 days


#5 posted 03-29-2015 09:16 PM

Haha, yes it sure was rustic. I’m not skilled enough for the fine stuff yet, and there isn’t much of a market for it in my area either. But people LOVE the rustic stuff, and I’m unashamed to be making it so long as I can create a quality product with it.

View cutmantom's profile

cutmantom

389 posts in 2496 days


#6 posted 03-29-2015 09:30 PM

Acclimating the material will help but that much wood will move, the same thing will happen but might less, I think air drying would take up to 3 months stacked with 1 inch sticks between the boards

View bondogaposis's profile

bondogaposis

4024 posts in 1812 days


#7 posted 03-29-2015 09:32 PM


Breadboards didn t expand. The “field” planks in the table shrank as they dried.
Acclimating the wood will help as you stated, but borg wood is really wet at first.
Bill

- Bill White

That is 100% correct. The only way to avoid it, is to use dry wood to begin with. Construction lumber is not dried to the extent that furniture grade lumber is.

-- Bondo Gaposis

View WhyMe's profile

WhyMe

612 posts in 1022 days


#8 posted 03-29-2015 09:57 PM

The breadboard is fairly stable. You need to let the field contract and swell and that is done using mortis and tenon joinery. The field if glued or screwed to the breadboard should only be done at the very center for only a few inches. The breadboard ends can be held using dowels with slotted holes in the field tenon. Also a spring method can be used where the breadborad has a slight arc and the ends are held tight by compression when pulling the center tight to the field.

View Ghidrah's profile

Ghidrah

667 posts in 683 days


#9 posted 03-29-2015 10:10 PM

Spruce doesn’t acclimate the way finish let alone C&B pine does its like a sponge. It’s going to move a lot no matter what you try to do.
My 1st water bed frame, (for me) was spruce, I made it to look like an old wooden ships captains rack, (low to the deck to minimize facial damage when I fell out) and short side rails beside the head and foot boards to make it even more difficult to fall out. I didn’t even try to apply a protective coat, it lasted 26 to 27 yrs. The only reason I got rid of it and built the new frame, (Oak, and mahogany) was my back. It’s much higher and no railing, I grew out of falling out of bed. The other frames I made were of VG Fir very nice, and rustic all together and one of Oak. Both materials appear to be very stabile.

-- I meant to do that!

View bandit571's profile

bandit571

14555 posts in 2144 days


#10 posted 03-29-2015 11:08 PM

“Framing lumber ain’t meant for..”
Ok, then

Not sure what you would call this, then?

Computer desk I am sitting at right now. Top was old Barn wood Sycamore 1×3s. It has bread board ends. Right now there is about 1/4” difference between the end of the breadboard and the edge of the top. Not a big deal, by July, the “gap” will be gone. There is a single screw up from the bottom to hold things centered, with a nail or two as it goes towards the ends. Nails will give a bit, again.

-- A Planer? I'M the planer, this is what I use

View WDHLT15's profile

WDHLT15

1572 posts in 1937 days


#11 posted 03-30-2015 12:02 PM

Construction lumber is dried only to 19%. You need to get below 10% so minimize seasonal movement. Extra drying is required if using construction lumber for inside furniture use.

-- Danny Located in Perry, GA. Forester. Wood-Mizer LT40HD35 Sawmill. Nyle L53 Dehumidification Kiln. hamsleyhardwood.com

View Yonak's profile

Yonak

979 posts in 982 days


#12 posted 03-30-2015 01:49 PM


IF the front edge is the “show” edge, pin the top to the breadboard edge there, no slots. Let the expansion/contractions happen to the back edge.

- bandit571

bandit, can you expand on this a little (no pun intended) ? Assuming the long grain of the boards are running front to back and the breadboard ends are front and back, are you saying hold the front tight and let the back move ? Wouldn’t both the front and back move equally ?

Also a spring method can be used where the breadborad has a slight arc and the ends are held tight by compression when pulling the center tight to the field.

- WhyMe

WhyMe, can you explain the “spring method” more. It sounds interesting. It seems like there would be surface height difference between the ends and the boards. ..So it would be a choice of where you want your mismatch to be, the edges or the top. Right ?

View WhyMe's profile

WhyMe

612 posts in 1022 days


#13 posted 03-30-2015 03:11 PM

I’m not sure if the term “spring method” is correct but the bread board is attached using mortise and tenon joinery but the ends of the bread board are not pinned with through dowels. The bread board edge that meets the field is slightly joined so when the bread board is in place there is the slightest gap in the middle with the ends touching the field. The bread board is glued in the center and is clamped pulling it tight closing the gap. This puts the ends of the bread board in a higher compression against the field to hold the bread board tight. The vertical/height is held in place by the mortise and tenon. Dowels can be use in place of the mortise and tenon as long as the dowel slots are elongated to allow for expansion and contraction. I’ve seen this method either used on the WoodWhisper or RoughCut but cannot find any video of it.

View jdh122's profile

jdh122

879 posts in 2279 days


#14 posted 03-30-2015 05:09 PM

While using dryer wood will help some, there’s no way to keep breadboard ends from moving. No matter what you do they’ll be totally flush twice a year and no more (when humidity conditions are the same as when you made it).
Generally breadboard ends are glued in the middle and then pinned with dowels in slots near to the ends. You could, as bandit suggests, glue it on one end and pin it with dowels in slots in the middle and other end. This will double the expansion and contraction on the end that is pinned, of course, but if it’s against the wall it might be a solution.
It’s not true that spruce will expand and contract more than other woods – its expansion rates are a bit higher than eastern pine, but less than any common North American hardwood (softwoods move less than hardwoods). Of course if it was wetter to start with it will move around more as it dries the first time, but after that first time it’s pretty stable.

-- Jeremy, in the Acadian forests

View rwe2156's profile

rwe2156

2190 posts in 942 days


#15 posted 03-30-2015 06:34 PM

Bondo hit the nail on the head.

Even if the wood is acclimated, summer built vs. winter built is a factor.

But because the wood shrunk THAT much, it was too wet when you built it.

-- Everything is a prototype thats why its one of a kind!!

showing 1 through 15 of 18 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com