tips on squaring 16 ft lumber

[tim vadas]

I need to square at least 3 boards of 16-17' white oak. Finished length i need 15', 7-8" wide. I had the wood cut several years ago, air dried 2 yrs, then also sitting in conditioning space for about a year. It came out quite straight, and i've got at least 8 good boards in case i mess something up.

The problem is i've got a 12x24' size shop and it's not easy to maneuver a 16' board. I've got a DJ-20, and 15" powermatic planer, so theoretically i could do it. I'd have to move the jointer and planer closer to the garage door, and figure out how to move some dust collection hoses.

I'm just looking for tips on the best/most efficient way to do this. I was thinking i would snap a chalk line on one edge of each board and rip first with a circular saw. Then i was debating on flattening one side with a hand plane vs. trying to use the jointer. There's no major cupping/twist or large knots, so i figured hand planing wouldn't be too bad. I figured the planer i could use by myself as long as i setup some additional infeed/outfeed support, but the jointer i would need some help with.

any thoughts or tips? Thanks!

[Joe Shinall]

I have a 16x20 shop and face the same problem. Everything is on mobile bases so I can pull everything near the door when I have to do long boards.

[david brum]

What will your finished thickness be?

[John Bailey]

Track saw for the edges.

[Jim Matthews]

What's the application for the finished boards?
What does one of these planks weigh? I'm thinking physics works against you, on a jointer.
Each board will want to fall away from the fence, or slide out from the bottom without feed rollers.

Running through a planer, you're likely to run into a jam, or serious snipe on one of the faces if the length puts upward force on the pinch rollers.
I'm thinking that you'll be better served to farm this job out, to a shop with more wiggle room.

If you are determined to manage this in your shop, consider doing some of it by hand. In this case, slower would make the process deliberate.
That means more control, in exchange for time.

I mainly work by hand, and would face plane the boards (one side only) and run them through the planer afterwards.
A series of light passes would keep the faces parallel as you approach the final thickness.

I would shoot the edges by hand, match planing.
Something this long is going to sag on your jointer - no doubt.

That would leave the center of each board "wider" as the ends droop and try to flex the board like a rainbow.

In any case, this isn't a solo operation if you're burning electrons.

[lowell holmes]

If you can't come up with a track saw, a clamp a shop made straight edge out of plywood 16' long.

Clamp the plywood straight edge to the boards and rip with a skilsaw guided by the straighe edge , providing a straight edge.

It can all be done on saw horses in the driveway.

[Richard Wolf]

I work with 16' all the time with stair stringers. A track saw is your friend. Almost impossible to use a jointer to flatten or straighten an edge. The planer is easy to use by yourself, support the one end until half way through and then run around to support the outfeed.

[scott vroom]

Tim, we successfully milled 14' x 7" white oak boards that we glued up for a (long) desktop. Before bringing the lumber home I paid a few dollars for the supplier to straight line rip 1 edge of the 4 planks.

We ripped, jointed, and planed the planks in our shop using carefully positioned roller stands and our combined 4 hands. It worked flawlessly with zero planer snipe and perfectly straight jointed edges for the glue up. We have a 15" planer and an 8" jointer with 76" table length. It can be done. The key for us was the SLR at the mill.

[Peter Quinn]

On lumber that long "square" is a relative term. You aren't going to flatten anything below 10/4 in any meaningful way over that distance, it will bow, sag, end up too thin, and probably resist your attempts to flatten it by moving. I've handled a lot of long/wide/thick/generally over sized lumber at work. I have "improved" long boards by jointing a bit off of each end to take out the most offensive bow/twist, but flat? Best bet is to use fairly flat boards for the long ones and chop any that are not already flat into shorter stock. IME You really don't need a board that long to be perfectly flat for most things, because it will generally conform to a flat surface or can be held to a flat assemble by other shorter members. I've made 15' long stair treads, they were "flatish", the stringers hold them down. Think really long rail on a custom cabinet, plywood holds it down. I've made them 14', definitely not flat, but they pull right down to the case and live flat there after. I'm guessing you are after edges that are mostly square to their relative position on the board and parallel? That is doable in a number of ways. My favorite for solo work for just a few boards is to create a straight edge using several rips of MDF spliced together with a few biscuits or a half lap, use a third piece that straddles both to clamp to to get that straight thing happening. THen use this and a router with flush trim or pattern bit to edge the boards. If the boards are way out a skill saw is a big help, you can certainly make a long guide for the skill saw too. I did a 24' run of porch that way, ran all the boards a bit long, put together a long straight edge skill saw guide, cut my edges, used the same jig to guide a slot cutter for end matching to receive a nosing.

I have a dj-20 and its not much use for boards over 10'. Each pass will approach straight, but its just to short to do the long stuff effectively. At least not glue line straight. Its not easy on a long air craft carrier 9' plus machine either but it can at least be done.

[tim vadas]

Thanks for your thoughts.

This wood is meant to cover an LVL beam in my living room. I had some trees down in my yard and cut into lumber and am in the process of building a fireplace mantel and this beam cover out of some of the wood, and eventually more trim work and maybe doors.

David, Finished thickness doesn't matter too much for the application, about 1/2-3/4".

John, Richard, I figured a track saw might be best for the edge. Unfortunately i don't have one, but i'll see if i can borrow one. Otherwise, Peter, Lowell, good idea on either the mdf or plywood straight edge and either a router or good circular saw.

Jim, i don't mind flattening by hand, and will give that a shot for one face. At least that i can do alone.

I'm glad to hear planing won't be too much of an issue. I've go a couple roller stands, and enough length on the board in case some snipe does happen.

and Peter, you're right, completely square doesn't matter per se, but i need square edges for a joint. I'm planning on trying a miter joint, but i know that'll rely on how straight the edges are. As you say, a longer board can conform a little better to an existing flat surface. Since this will be screwed to a beam, i'm hoping that will aid in any slight gaps in the miter joint.