making wood flat

[bobbyb619]

I am new to wood working a need some advice. I know how to make the edges straight on my wood, but how do I get my wood flat without it bowing or cuping? It seems that no matter how picky I am when I pick out the lumber it is cupped or bowed in some way when I am building. Do I have to plane it? If yes, won't I get varing thicknesses in my projects? Thanks for any advice!

[MikeMc]

I am new to wood working a need some advice. I know how to make the edges straight on my wood, but how do I get my wood flat without it bowing or cuping? It seems that no matter how picky I am when I pick out the lumber it is cupped or bowed in some way when I am building. Do I have to plane it? If yes, won't I get varing thicknesses in my projects? Thanks for any advice!

Hi bobby! Welcome to woodworking.

Almost every piece of lumber you will buy will be distorted in some way. Typically you go through a process known as milling lumber or milling a board.

This is usually done on a jointer for the first 2 faces, then on a surface planer for the 3rd face and finally on a table saw to finish the final side.

You typically purchase lumber bigger than the thickness you want and plane it down to size.

Marc has an excellent video on the subject. I believe it is called the Jointer's Jumpin.

Good Luck!

[kforsythe@gmail.com]

Hi bobby! Welcome to woodworking.

Almost every piece of lumber you will buy will be distorted in some way. Typically you go through a process known as milling lumber or milling a board.

This is usually done on a jointer for the first 2 faces, then on a surface planer for the 3rd face and finally on a table saw to finish the final side.

You typically purchase lumber bigger than the thickness you want and plane it down to size.

Marc has an excellent video on the subject. I believe it is called the Jointer's Jumpin.

Good Luck!

Marc's video is definitely a good place to start. Here's the link:

http://thewoodwhisperer.com/episode-6-the-jointers-jumpin/

[BillN]

bobby,

Ditto on the previous posts. Keep in mind that the wider the board the more apparent the warp, particularly over time. When you buy wood, give it time (perhaps as much as 2 weeks) to get used to the moisture in your shop. If you're using plain sawn wood it is a good idea (depending on what you want the grain to look like) to cut the wood into smaller strips (say 4 inches wide) and flip every other one so the ring patterns on the ends go up, down, up, down as opposed to one wide board with the rings all going the same way. To some extent this will minimize the warping. You can also minimize warping and cut movement (seasonal expansion due to moisture changes) in half by using quarter sawn wood. It is significantly more expensive, but may be worth it if you have a wide flat expanse. Finally, if you have a wide flat area with plain sawn wood, like a tabletop, consider trapping the ends with what is called breadboarding (a board on either end running perpendicular to the orientation of the boards) You definitely have to take into account movement when you do this, but the breadboards will counteract the tendency of the boards to warp.

[jgfore]

DIDO to MikeMC. However, if you are like me and do not have a jointer (YET!), then I have to do all of my milling with my planer. It takes several more steps, like placing a known flat board beneath the board that I am trying to mill so that I am getting a flat surface and not just a parelle one. If you have a jointer, planer and table saw, then follow marc's video.

Jeff

[jgfore]

I almost forgot. If you are worried about all of your boards being different thicknesses, send them all through the planer on the same setting and......WhaaaLaa, they are all eaqual on thichness.

Jeff

[RenaissanceWW]

Bobby, welcome to woodworking and you have found the right place for your questions. Keep asking them. I can see why you would think that you would end up with varied thickness. The first step in milling lumber is to establish a flat face and a flat and square edge. You can do this with a power jointer, or a hand plane. Once those sides are flat and true they become your reference faces. Now you can work on getting the opposing face and edge parallel to those reference faces. A thickness planer can make quick work of the opposite face and a table saw can match up your edge nicely. You can also use the same hand plane to true these but you will need to mark a line from the reference face to plane to.

Stop any of us if you are not sure what we mean. Since we don't know what kind of tools you have it may be hard for us to direct you but we are happy to help and thrilled to have another new woodworker in our ranks.

[russjohnson]

How critical is it to wait before milling if your buying the lumber from a dealer about 15 miles away? Is it as critical to wait 2 weeks when the climates are so similar already? Thank you for your advice

bobby,

Ditto on the previous posts. Keep in mind that the wider the board the more apparent the warp, particularly over time. When you buy wood, give it time (perhaps as much as 2 weeks) to get used to the moisture in your shop. If you're using plain sawn wood it is a good idea (depending on what you want the grain to look like) to cut the wood into smaller strips (say 4 inches wide) and flip every other one so the ring patterns on the ends go up, down, up, down as opposed to one wide board with the rings all going the same way. To some extent this will minimize the warping. You can also minimize warping and cut movement (seasonal expansion due to moisture changes) in half by using quarter sawn wood. It is significantly more expensive, but may be worth it if you have a wide flat expanse. Finally, if you have a wide flat area with plain sawn wood, like a tabletop, consider trapping the ends with what is called breadboarding (a board on either end running perpendicular to the orientation of the boards) You definitely have to take into account movement when you do this, but the breadboards will counteract the tendency of the boards to warp.

[bobbyb619]

Thank you all for the great info! I have been learning alot on this website! Does the same methods apply to sheats of birch plywood (4' x 8') when ripped to specs that I need? Do these boards tend to be flat or will I have to do just as much mill work as milled lumber? Thanks again!

[bobbyb619]

Can I do the job with a tablesaw and RIDGID 13 In. 3-Blade Thickness Planer or do also need the jointer/planer in addition? Thanks

[PMR]

Does the same methods apply to sheats of birch plywood (4' x 8') when ripped to specs that I need? Do these boards tend to be flat or will I have to do just as much mill work as milled lumber? Thanks again!

Welcome to the forum, the veneer on plywood is to thin to do any milling to it. I believe a better quality plywood such as baltic birch will be flatter than cheap ply. Pat

[PaulMarcel]

I know the ply comment was a tangent of sorts, but I'll add to it (tangents are fun!) I've been using veneered wafer board on the past couple projects. What I like is that 3/4" is 3/4" and 1/2" is 1/2" instead of the 'nominal' size that isn't the same lot to lot. Very sturdy, void-free, and best of all, the veneer layer is significantly thicker. That doesn't mean you can chip carve the thing, but you do have to go a long long way with P80 to burn through it.

[bobbyb619]

that is what I thought thanks!

[went_postal]

Can I do the job with a tablesaw and RIDGID 13 In. 3-Blade Thickness Planer or do also need the jointer/planer in addition? Thanks

NEED is kinda strong. =). Could do it with hand tools like planes and whatnot. I have also seen folks make sleds for their planers to edge joint boards.

I will say this though... Once you have a jointer you will wonder how you went without.

[went_postal]

How critical is it to wait before milling if your buying the lumber from a dealer about 15 miles away? Is it as critical to wait 2 weeks when the climates are so similar already? Thank you for your advice

My lumber provider is about 25 miles away but they store their lumber in a much different environment than my shop. Their hardwood house gets to like 120 in the summer and 10 in the winter. My shop goes between 30 at the coolest and 80 at the warmest. makes a big difference. I have bought dead flat wood from them that tied itself into a knot in three days.

Keep in mind the wood at the store probably has a few thousand pounds of other stuff on it at any given time and may not get the same airflow that it gets in your shop.

I brought home a super straight yellow pine 4x4 a few weeks ago the bowed out really bad just from being in the back of my pickup and getting some sun.