Joining a long board

[Susumu Mori]

Hi all,

I'm wondering how you join a long board using a jointer. This is especially an issue for Euro combo machines which tend to have shorter infeed/outfeed beds.
Usually, it is recommended to join concave face down, which stabilizes the board better than convex down. However, if the board is longer than the bed, the trailing end of the board is initially outside of the bed and then as it approaches the bed, the board is raised, potentially making the joined face curved.

For the euro jointer, extension tables can be added but they have to be accurately co-planer to the beds and we need two of them.

So, I usually flatten the top of the convex face by a hand plane to stabilize the board and join the convex face down. It is a bit difficult but usually works for a board up to twice as long as the bed.
I'm not sure if this is a better way.

I would appreciate if you share your approach.

Thanks,

Susumu

[Kevin McCluney]

I place the convex side down and make one or two light passes with the jointer, careful to make the cuts towards the center of the curved board. It's flat enough along the jointed edge at that point that remaining passes are no different than with a less curved board. Then I use the table saw to make the opposite side parallel to the jointed edge. Alternately, a track saw could used to make one side side straight, as could a router with a long straight edge. And of course those with sliding tables for their table saws likely would gravitate to that method first. For that matter, a jig saw, circular saw, hand saw, etc. could be used to remove the high spot(s) and then from there the jointer could be used.

[glenn bradley]

However, if the board is longer than the bed, the trailing end of the board is initially outside of the bed and then as it approaches the bed, the board is raised, potentially making the joined face curved.

You are correct. The jointer like any fixed feed-path machine requires that the stock be controlled. While the tablesaw and the planer can be a little more forgiving, due to the material already having been prepared with some other milling operation, the jointer is less so. Most of the complaints about jointer results I see on forums are due to improper stock support. This is tailed closely by folks wanting to mill unnecessarily long stock instead of breaking things down before milling.

As you mention, the stock needs to have its "lowest" points on the same plane just below the cutterhead height in order to assure a proper cut. This is true for face or edge jointing. I have 44" of infeed table ahead of my cutter and this handles most parts for the furniture that I make.

On the occasion that I need longer infeed support I use roller stands for face jointing. I have a small adjustable height table for materiel with crook or kink as the "points" need to be supported through the cut and a roller stand will not provide this when edge jointing crooked material. Several of the trade rags have had articles on shop made support stands. These or a "table" add-on for your current roller stands could cure your ills.

Afterthought: For boards that are nearly short enough to be supported by my existing infeed I have a couple of processes that save me a bit of time. The first is to simply free hand a "pretty straight" edge onto the material with the bandsaw. This will often make your existing infeed length adequate. The second applies to edge jointing. I will start in the middle of the board and flatten one end of the board. I will do this swapping the board end for end until I have enough milled surface to set on the infeed length that I have. The milled ends are not at the end result I am after but, I have effectively moved the lowest point onto the existing tables and can mill correctly from there.

Just because I do it doesn't make it right but, something here may be helpful ;-)

[Max Neu]

Sometimes it's easier to get the worst of it with a hand plane,then clean it up with a jointer.

[John T Barker]

I'd find a different jointer. I have, on occasion, gone to pro shops in my area to surface boards my machines (width...my jointer is 12"x72") could not handle. When I worked in a fully outfitted pro shop we often had woodworkers stop in and ask a favor. Our foreman would usually pick a guy to do the job and we'd get a couple of bucks out of it.

[lowell holmes]

I run the board concave side down just taking a bit off of the ends, repeating until it is straight. I then joint the convex side on the table saw.

With a radical bow, I use my 607 Bedrock plane and finish on the table saw.

[Keith Weber]

If your boards are that bowed that your jointer is too short, crosscut them to approximate length first, before taking them to the jointer. If your finished board is that long, find a straighter board, or just make multiple passes concave side down.

[mreza Salav]

I put the face which will have the two ends touching the bed down, then cut a little bit of the front end back and forth. Flip end for end and cut a little bit of the other end in a few back and forth motions until the "high" points are mostly gone. Then join the board in a usual manner, while paying attention to apply pressure mostly on the front and the end of the board and little pressure in the middle until you hear a consistent cutting sound across all the board.

[Jim Becker]

I very rarely take long boards to "finished dimensions", so this hasn't been much of an issue with my J/P. While I do skim long boards initially before storing, them, I break things down to component rough sizes before milling. Therefore, it's rare for anything longer than about 5-6 feet having to be processed for the type of projects I do. If I truly needed to do something "finished dimension" with a long board and it was critical to be spot-on, I'd likely work up some kind of temporary bed extension. Knocking things down a little with hand planes is very much a good idea to streamline the process, too, and reduce passes over the tables.

[Tom M King]

One reason why I have two helpers.

[Hoang N Nguyen]

For long curved boards like that, I just rip it down length wise with my track saw to get curve out and then make a pass or 2 with the jointer.

[lowell holmes]

Sometimes it's easier to get the worst of it with a hand plane,then clean it up with a jointer.

That's why I have a Bedrock 7. :)

[Dave Arnett]

For long curved boards like that, I just rip it down length wise with my track saw to get curve out and then make a pass or 2 with the jointer.

Yep!

If nothing else, snap a line, get out the circular saw, then make a pass or two.

[Susumu Mori]

Thank you all for helpful tips.
They all make sense, but, I forgot to mention that the particular problem I'm having is for the top of a workbench. The joined face is more than 3-inch thickness. So I can't use a table saw or a tracksaw to establish the first rip line. Jointer is pretty much the only option. The board is 5-foot long. Concave down would definitely have a problem as one of the point of contact is outside the table....

[Richard Shaefer]

Hi all,

I'm wondering how you join a long board using a jointer. This is especially an issue for Euro combo machines which tend to have shorter infeed/outfeed beds.
Usually, it is recommended to join concave face down, which stabilizes the board better than convex down. However, if the board is longer than the bed, the trailing end of the board is initially outside of the bed and then as it approaches the bed, the board is raised, potentially making the joined face curved.

For the euro jointer, extension tables can be added but they have to be accurately co-planer to the beds and we need two of them.

So, I usually flatten the top of the convex face by a hand plane to stabilize the board and join the convex face down. It is a bit difficult but usually works for a board up to twice as long as the bed.
I'm not sure if this is a better way.

I would appreciate if you share your approach.

Thanks,

Susumu


the euro jointer extension beds don't need to be perfectly co-planar. they have to be close, but wood is in and of itself flexible. for example, if you get a 6' long board on a dead-flat 4' long euro jointer and the 2' extension on the ends droop or rise 1/8"", the wood is flexible enough to wane either way in service without fighting you as you work it into the overall final product. (unless you're working a significant timber). Keep in mind that woodworkers have been building dead-straight joints using little more than 24" long jointer plane for about, oh,.. 2000 years.

[Susumu Mori]

Richard, this is so true......
If I understand you correctly, what the point to fight over 1/64 of inch over 5-foot long board because the board flexes.