Jointing 8 foot boards

[Joe Hillmann]

I am planning to build a decent work bench and am practicing by building a stand for my lathe and I am having a hard time jointing the 5 foot 2x4 for the top. When I am done they have about 1/16 concave to them over the 5 foot length. Am I supposed to do strokes the entire length of the board well walking or do I do 2 feet, take a step, do two feet, take a step and then do the last foot?

[Zach Dillinger]

I do it in one smooth motion, no stopping and starting. 1/16 over 5 feet isn't terrible. I'd probably take a pass or four at each end, check it and call it a day. What length of jointer are you using to do the 5 foot piece?

[Joe Hillmann]

It is a 14 inch stanley number 5.

[James Owen]

I am planning to build a decent work bench and am practicing by building a stand for my lathe and I am having a hard time jointing the 5 foot 2x4 for the top. When I am done they have about 1/16 concave to them over the 5 foot length. Am I supposed to do strokes the entire length of the board well walking or do I do 2 feet, take a step, do two feet, take a step and then do the last foot?

You can do either. I've found that I get better results by keeping the plane in constant motion, so I normally walk as I plane along the entire length of the board. BUT....that is the technique that happens to work best for me; you may find that your results vary....

It is extremely difficult to get a genuinely "flat" edge, but much easier to get a slightly concave edge, so a lot of woodworkers making panels and table tops will deliberately introduce a very small amount of concavity (1/64" +/-) into their board edges. It's easier and faster, plus the compression on the ends helps keep the ends from spreading with changes in humidity.

So, if you are looking to do "sprung joints" on your boards for the top, 1/16" is probably a bit too much (if you're using Southern Yellow Pine or Douglas Fir or a softer hardwood like Poplar, it will probably work fine -- they all compress fairly easily; but hardwoods like maple, ash, or oak compress much less, and work much better with less concavity); 1/64" or maybe even 1/32" -- just enough to see a sliver of light under a straight edge -- generally gives a stronger joint.

If you don't already do so, try running a squiggly pencil line down the length of the board: it will help you see where and how much you are removing, and help you keep your edge flatter (and more square).
_________

You might want to try a longer plane, if you have one available to you. A #5 will certainly work, but a #6, #7, or #8 will make getting a flat edge much easier.

[Sean Richards]

It is a 14 inch stanley number 5.

That is a bit on the short side. Having said that sounds like you are getting pretty close.

As for technique (as above) you want to try to plane the entire length of the board with one fluid motion. However with the shorter #5 you are going to need to pay a lot more attention to any high or low spots.

[Zach Dillinger]

It is a 14 inch stanley number 5.

14" is a bit short to joint a 5 foot length. The rule of thumb is that you can effectively flatten a board that is 2 to 2.5 times longer than the plane. For a 5 foot board, I'd be pulling out my 30" jointer plane. James also has the right idea with regards to sprung joints.

[Joe Hillmann]

James, can you explain what you mean about using a squiggly pencil line?

[Roderick Gentry]

The way you joint boards is you start in the middle and keep at it till the blade stops catching, and keep moving out towards the ends until the whole board can no longer be cut from say within one inch of the end to the other. This is a sprung edge, and frankly 1/16" would be good for even a jointer. The only problem with that is if the boards were so stiff they could not be easily closed together. If you want straighter than a jointed and sprung edge, you reverse the process but this is not as automatic and eye closed a process. You have to practice it a few times till it falls in place. You work the opposite ends, and then the opposite thirds and finally get to a point where you take a full length stroke, and the piece is flat. This becomes pretty automatic with a little practice. The reason one can get it down so easily is because one first went through the springing process, and the edge has a known straightness, so backing it out is relatively simple.

Sprung joint work well on high aspect ratio boards. Something like a guitar soundboard where the board is 8" x 22" is essentially impossible to spring together with clamps, particularly given the thickness of the material. But an 8" x 8' board would be relatively more flexible, and would easily spring an 1/8" more.

[Jim Matthews]

Have a look at the match planing method demonstated by Bob over at the Logan Cabinet Shoppe podcast;
Episode #28 (http://logancabinetshoppe.com/blog/2010/10/episode-28/) You can also help things along by marking one board with chalk and rubbing the faces together - where the chalk transfers, you have a "high" spot.

[Jim Koepke]

I am planning to build a decent work bench and am practicing by building a stand for my lathe and I am having a hard time jointing the 5 foot 2x4 for the top. When I am done they have about 1/16 concave to them over the 5 foot length. Am I supposed to do strokes the entire length of the board well walking or do I do 2 feet, take a step, do two feet, take a step and then do the last foot?

A way that works for me on longer stock is to position myself with the plane's toe registered on the work and then lean in to start the cut just as my first step is starting. With a little practice this becomes smooth.

Though a #5 is a bit small for this job it can be done.

Mark the pieces so they are always tested in the same orientation. Use a pencil to mark the high spots and take them down a few shavings at a time and recheck your progress.

A .010 shaving is a pretty heavy shaving. A 1/16" is .0625

Even with a lighter shaving it shouldn't take too long to just trim down the ends of the 2X4s.

jtk

[Russell Sansom]

I use a shooting board for ALL jointing operations. It's almost impossible to sweep out a single continuous, "uniform" stroke with a #8 lying on its side. As one member here has pointed out in the past, you can measure and understand a "hollow." It's much more difficult with a convex face. My standard practice is to establish a small hollow then take a couple light passes on the extremes. It only takes a few minutes with a spirit of experimentation to get pretty good at this kind of joinery.

I agree that high-aspect ratio boards spring more easily, but I think any edge joint is better off with some hollow, however slight a spring the board will allow. There might be some exceptions, but I can't think of one. I really don't mean to be argumentative, but I have no trouble springing an 8" wide length of guitar soundboard. It might take a few tries to get the "best" hollow, but one can be found. Granted, this is a lot easier with 8" widths of spruce on a harpsichord soundboard where the boards are up to 6 feet long...Now That's a high aspect ratio.

Just a data point from my tiny world.

[Prashun Patel]

This might be heresy, and I respect that you'd like continuous boards. I'll throw this out just keeping in mind that you're making a workbench.

You can cut your 8foot pieces into 2-4ft sections. They will be easier to joint and will preserve a little more width. Staggering the butt joints will make the laminations plenty strong. Just a thought.

[Terry Beadle]

One thing to keep in mind, especially when using a #5 ( which is a jack plane and not a jointer ) is that the goal is not to get a shaving the entire length of the 8 foot edge. You must work high spots to equal to the low spots. Your 1/16th concavity is a good result of your full length work but using the squiggly line technique mentioned above, remove the pencil marks near each end until you can remove the entire squiggly marks for a 2 ~ 3 foot section with one planing stroke.

Recheck your flatness. Use your eyes as the human eye can be trained to detect even 1 thou out of true.

Another thing is make your own long straight edge out of some stable hard wood. Use a set of dial calipers in this effort. Then use the 4 ft straight edge to check your work as you go along with the pencil marks and you will get great results with a bit of practice.

I guess the main thing is to not think a long shaving is a good result ( it can be but not the prime work idea ) but rather getting all the high spots on an edge even with the lowest flat area.

Stop cuts are the best way to true an edge IMO. Read up on David Charlesworths techniques of planing. He uses stop cuts and a curved plane blade edge to control flatness and squareness. Works great !

Enjoy the process.

[Joe Hillmann]

How do you use a shooting board for jointing?

I realize this is just a work bench but it is also practice on how to get a board straight on one edge. For now I went with matching one board to the next by planing where they touch until they touch nearly the entire length of the board but would like to be able to make a truly straight edge.

Also my plane iron has a bit of a curve to it. Not much I just put a more pressure on the corners as I sharpen it to prevent tear out and I find the curve helps to keep the edge square with a face. Would the curved blade make jointing more difficult?

[Jim Koepke]

How do you use a shooting board for jointing?

Harry Strasil once showed a long shooting board for edge joining. If one needs perfection in an edge, it might be worth making one.

For most edge joining work it isn't needed.

If you are going to join long pieces for a bench, my suggestion is to acquire a plane like a #7. #8 or a long wooden jointer. It will make your work a lot easier.

jtk

[Zach Dillinger]

If you are going to join long pieces for a bench, my suggestion is to acquire a plane like a #7. #8 or a long wooden jointer. It will make your work a lot easier.

jtk



Winner, winner, chicken... something. Buy a 30" woodie jointer. You'll never regret it. I used a 26" for a number of years but finally bought a 30" at an auction last year (same place I scored the set of Gabriel hollows and rounds). I love that plane.