Warping oak a problem?

[Stick in Mud]

Funny that's there's another thread about idiots asking dumb questions, but....

I'm considering making a bookshelf, and I'm able to get my hands on some 1x12x12 oak boards for super cheap. I'd be copying the design of a freestanding bookshelf I've seen in a friend's house....He uses 10 ft boards, supported on both ends and throughout the span by these:

He did not use oak because it was too expensive, but in our discussion about whether I should make one for myself, he said a 12'' wide oak board would warp too much. Not knowing a thing about wood, but disagreeing with him regardless, I figured I'd ask people who know what they're talking about to see if there's a consensus.

Would I need to worry about warpage in a 1'' x 12'' x 12' oak board that was used for an indoor bookshelf?

[Rick G]

A single large, thin piece like that will warp a bit over time. Imo if you realy want to use oak, and it needs to be that wide and thi,n I would saw the board in 3in strips and glue it back together alternating the grain every other piece.

[PurpleFloyd]

If you are intending on using it as a flat shelf then yes, it would be a problem. That being said, if you can draw a sketch of what you are looking to do I can help you come up with a design that would allow you to use them and not worry about warping if you give me some creative flexibility.

The idea of ripping and regluing would help but it would not guarantee that things would not warp even after going through the work ( I do this for a living) and after all of that you would end up better off using an MDF core ply like you have pictured above.

BTW- I know that many people think of the MDF and Particleboard cores as inferior to the laminated wood plys of conventional plywood but in reality these days those 2 cores are the most stable and best performing cores you can buy. I have several examples of shelves of all cores types that I have used over the years and the ply cores of even plywood has warped but the p-board and MDF have remained flat and stable.

Anyways, sorry to get off on a tangent. If you need any help let me know.

[Stick in Mud]

Thanks for the advice, guys. I was under the impression (incorrect as all of mine are when it comes to doing anything useful ) that a hardwood like oak would allow me to have fewer supports across the span--and therefore more room for books. Not having begun any work yet, I can go with whatever works best, as long as it's not uber expensive.

For what it's worth, my buddy used pine and put the supports about 20'' apart. So far he's had no problems with sagging. Essentially, the bookshelf is nothing more than the supports I've shown in the photo with boards on top of them. Nothing is glued or screwed together, nor is anything (in his case) braced or connected to the wall behind it.

Of course, I don't need 12 foot boards. That's just the span I'm looking to fill.

[delcecchi]

Ah, the upscale version of the "bricks and boards" we used back in the day.

[PurpleFloyd]

Thanks for the advice, guys. I was under the impression (incorrect as all of mine are when it comes to doing anything useful ) that a hardwood like oak would allow me to have fewer supports across the span--and therefore more room for books. Not having begun any work yet, I can go with whatever works best, as long as it's not uber expensive.

For what it's worth, my buddy used pine and put the supports about 20'' apart. So far he's had no problems with sagging. Essentially, the bookshelf is nothing more than the supports I've shown in the photo with boards on top of them. Nothing is glued or screwed together, nor is anything (in his case) braced or connected to the wall behind it.

Of course, I don't need 12 foot boards. That's just the span I'm looking to fill.

If that is the case you can certainly span that far with no issues. IME you can generally span 36-42 inches before 3/4 material will have sagging issues.Also If you keep them full of books they probably won't warp or at least not as likely.

[Stick in Mud]

Ah, the upscale version of the "bricks and boards" we used back in the day.

LOL. Yes, I almost described it as the "kind of bookshelf you see in dorm rooms and the garrets of people with English degrees," but then I figured that might offend some of the humanists out there.

[Stick in Mud]

Thanks for the advice, Purple. I tried to PM you, but your inbox is full....

[PurpleFloyd]

Lol. I am the HSO Black Sheep. No messages in my in box at all. I think it is a forum glitch.

If you need anything let me know and I can covertly plant my email in a post for you.

[Stick in Mud]

Maybe someone down in Silly Town is trying to prevent you from contacting others?!?

The shelf will be used solely to store books....not encyclopedias or anything, but just regular old paperbacks with the odd hardcover thrown in.

In that case, would you recommend ripping them and re-gluing to avoid warping?

I also assume (which means I'm probably wrong...) that the length of the board would matter. I could just as easily use two 1x12x6 or three 1x12x4 instead of one 1x12x12. Might that minimize any potential problems?

[delcecchi]

I just went and looked. I have a bookcase in sort of craftsman/stickley sort of style. Shelves are 33 by 9 of 3/4 allegedly oak. Supported by two pins on each end that go into holes in the uprights and the shelf sits on them.

Loaded full with hardcover books, mostly cookbooks, and they have no perceptible sag after maybe 6 or 8 years.

For what that's worth as a point of reference.

[PurpleFloyd]

Maybe someone down in Silly Town is trying to prevent you from contacting others?!?

The shelf will be used solely to store books....not encyclopedias or anything, but just regular old paperbacks with the odd hardcover thrown in.

In that case, would you recommend ripping them and re-gluing to avoid warping?

I also assume (which means I'm probably wrong...) that the length of the board would matter. I could just as easily use two 1x12x6 or three 1x12x4 instead of one 1x12x12. Might that minimize any potential problems?

To be honest with you, for what you are doing I am not sure you are going to gain an appreciable amount of benefit from the work of ripping and regluing the boards and unless you have the equipment to do it right(good quality table saw, jointer, planer, sander etc) then I would leave them the full width. One thing to remember- when you rip and re glue the boards, unless you have some industrial type clamping systems you never get the joints perfectly flush and so by the time you plane and sand them back flush, you are probably losing 1/16 to 1/8 inch on thickness depending on your skill and equipment. That reduction in thickness is going to reduce the weight capacity and will sag sooner.

As far as warping, if you have books on them and if they have been stained and (most importantly) clear coated then they will more than likely stay flat if they have been properly kiln dried. If not they won't no matter what you do. If they start to warp, a few screws into the supports will stop that in it's tracks.

[PurpleFloyd]

just to clarify- 2 terms have been used in here and they are sag and warp.

Sag is caused by too much weight on an object over too long of a span. If you do get one that starts to sag, flip it over.

Warp is where the wood twists in an uneven fashion such as a corner lifts etc and that is caused by the wood reacting to moisture. They way to combat that is to restrict the ability of the pores to take in and lose moisture, generally by a clear finish. And also by humidity control.

[Tom7227]

I have done a couple projects where I put oak and pine together to make wider boards and what Purple said about things not lining up has been true in efforts. The first one I used glue and a biscuit joiner and all the glue got to be a real PITA and made it tough to get the stain to look decent. With some more experience I may have better luck. A big problem for me was that if I tried to put enough torque on the clamps to draw the boards together tightly they would cup up and get all kaflooey. So then I clamped some boards to try and keep the others flat and they ended up being glued to the board I wanted to keep.

This time I bought a Kreg Jig and it was pretty slick. Still had trouble keeping things even and had to do some sanding but the Kreg was a lot easier to do than trying to glue and clamp.

[Stick in Mud]

Man, I love this forum. Thanks for the patience and the help. Even if the shelf doesn't work out, I owe you one...a trip out on Mille Lacs, perhaps? You can come along, too, Del.

One more question: Would it matter if we staggered the supports, or would it be best to have them lined up vertically? Or doesn't it matter at all? Here's a sketch of one way of staggering the supports:

The gaps between the supports would alternate on each level, four feet on one and three on the next. Conceivably, the supports on the very ends of the levels with four-foot spaces could be moved in to shrink that 48'' span.

[Surface Tension]

12x8', are you building this in your living room because I don't see it being moved in after its assembled.

Your shelves are spaced at 1'. I have books that wouldn't fit into that shelf.

I'd go with pins and make the shelves adjustable.

I think I'd go with four 3' book cases. That takes care of the warp but you could still get the cupping. Think cabinets and how their tied together as one unit.

Building the carcass out of MFD with veneer and oak face frame. Shelves of the same with

a oak 1x2 with a dado that slip into the shelf face. That'll finish the edge and give you rigidity to the shelf and no sag. You could tie the look together with a cap kicked out for under lighting and finished of with crown molding.

Where the 3 shelves come together celebrate that with mass. A thick vertical line using 1x3 oak proud of the face frame. The idea there is your not going to hide the sections so make their presence dramatic.

[delcecchi]

Thanks for the offer. Mille Lacs, isn't that where the walleyes all got netted? (joke joke not serious, don't go all sillytown folks)

I would line the supports up, or you end up with the situation that caused the walkway collapse in KC.

http://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse

The way you have it drawn each shelf has to support the weight of all the shelves above it. If the supports line up, the weight is carried down the stack of supports.

I hope this is an understandable explanation

[Tom Sawyer]

Carmike, you will definitely want to build this shelf unit with a face frame front. This will eliminate your warping issues, add strength, and give the bookcase a finished appearance.

PM if you have any other questions. I tried sending you a PM, but your mail box must be full.

[PurpleFloyd]

Man, I love this forum. Thanks for the patience and the help. Even if the shelf doesn't work out, I owe you one...a trip out on Mille Lacs, perhaps? You can come along, too, Del.

One more question: Would it matter if we staggered the supports, or would it be best to have them lined up vertically? Or doesn't it matter at all? Here's a sketch of one way of staggering the supports:

The gaps between the supports would alternate on each level, four feet on one and three on the next. Conceivably, the supports on the very ends of the levels with four-foot spaces could be moved in to shrink that 48'' span.

Never been to Mille lacs but would love to fish for some perch there some day. It would be better to line the shelves up but for asthetics you could stagger the. A little and be OK. Try offsetting them 3-4 inches and you will create a more interesting shelf.

While I agree that face frames do add to stiffen the case I have built probably thousands of both traditional framed and the euro frameless cabinets and they are both strong enough. Interesting story- my shop burned to the ground 4 years ago and as it was up in flames I could see an assembled set of kitchen cabinets that were done and staged at the front of the shop. After hours in the burning building and the roof collapsing on them they actually were still standing and holding up he roof beam. Then they brought in an excavator to clear out debris and it turns out they were not strong enough to hold up to the weight of that thing. So depending on the load you are placing on it I would argue that you can get by without the face frame.screwing it together would help and give it that college dorm feel.

If you needed to build a face frame unit with adjustable shelves and the whole 9 yards I could have you come down and we could design it and cut the parts on the cnc.

[Stick in Mud]

Thanks for all the advice, guys. I'll keep thinking about it, and if I do decide to make it, I'm sure I'll be back with more questions.

[h8go4s]

Have you considered a book sale?

[Stick in Mud]

LOL. Yes, I most certainly have. I did already get rid of a ton of them during the move, too.