Hoping for your collective help…
I have a 2″ by 3-1/2″ by 72″ long piece of poplar that will be mounted to a wall and needs to compensate for the wall being out of plumb. Specifically, the 3″ side is going to lay flat on the wall – the wall is quite straight but out of plumb by about 1/4″ over that 72″ span. So the board needs to taper from 1-3/4″ to 2″ over 72″…
Any suggestions on how to make that taper on that wide a board?
(My jointer infeed table is only about 42″ so don’t think I can use that. In the past I have used a tablesaw with a sled, but 3-1/2″ tall isn’t going to work. Thought of making a sled for running through planer, but that sled will need to be VERY stiff or it will just bend…)
Replies
Your description of the dimensions confuses me. Your board is 72" long. Is it 2" thick and 3.5" wide or the other way around?
It sounds like it's 3.5" thick and 2" wide. If so and you have access to a bandsaw, then you simply draw a line from 2" at one end to 1 3/4" at the other and bandsaw to that line (if it needs to be dead straight, you can find articles on FWW on how to make a taper jig for the bandsaw.
If it's the other way around, and you need one end thinner than the other, I'd suggest that perhaps you can mill the board to the thin dimension and simply add a 1/4" shim to the back of the thicker end. Unless that gap is going to be visible, I would think that would do the trick.
However, you can also use the first technique to resaw the board with a tapered thickness.
If no band saw, I think you might be in for a lot of hand planing. The good news is that it's only 1/4" max that you have to remove.
That would be a job for a handplane for me. Poplar planes effortlessly and you only need to taper ¼" so 15 minutes work and it's done. Simply scribe a line on both edges and start planing at the end that needs to be reduced the most and gradually work back 6" or so with each pass and you will quickly have your taper cut, safely and quietly with the added bonus of being able to adjust for any high or low spots in the wall as you go.
I would use a tracksaw, but one that can cut 3" is very heavy and expensive. My Mafell could do it, but expect a hernia every time you lift it.
Failing that, I would cut a slot 2.5" wide and 1/2" deep down the centre of the piece with a router and edge guide. This means you now have two separate sides to scribe to the wall, but they are only 1/4" thick. This makes them very easy to plane or sand to a precise scribe line.
Unless you really need all that surface area in contact with the wall, this is the easiest option.
That’s a perfect job for the jointer, run a pencil line at the desired angle and run the wood half way then re-run part way until parralel to the line and run all the length to the line.
If you are not comfy on the jointer you could mechanize this partway by attaching temporary wedges to the board... say 1/2" wide on both sides. Then you could make passes over a dado set and get the depth just a hair deeper than what you need.
When you pop off the wedges and you'll have a 1/2" of meat on either edge to hand plane down to a perfect fit with the center of the board never making contact with the wall.
A 1/4" taper along 72" is a very shallow taper with not a lot of material to remove. I'd use a long straight edge to draw the line and then either gently sand or handplane to the line.
Follansbee would use a hewing hatchet.
I would just shim behind the board while attaching to the wall.
Otherwise I would do as the last poster offered. Draw a line and use a track saw.
I'd use shims too. We're not building clocks.
Problem with shims is that this is a VERY visible spot and those shims will be extremely visible - and too big a gap to caulk.
One suggestion is to use a L fence and your table saw. Two side tape a runner to the top with the desired taper then run thru the saw. Be careful with the force against the fence, just keep it in contact.
I agree with ysu65. However, due to the thickness (3 1/2") you will need to flip it over after the first cut to finish it.
Thanks for the suggestions all!
- Hard part with either tablesaw and L-fence is trying to keep the board from tipping while running it through and then flipping and getting cuts to line up. Similar issue with track saw trying to balance the track on the 2" edge.
- Difficulty with Bandsaw is also keeping it vertical and at the start of the taper you are basically doing a skim cut...
- After the jointer was suggested, I went ahead and drew the line and started with the "aft" end of the board just at the start of my in feed and mid board just past the helical head. Few passes to get the slope right and then was able to run it full length and it came out perfectly.
Thanks again for everyone's help!
A "trick to start a skim cut would be to use some cyanoacrylate glue to add a bit of width to just before and after where the cut starts so that way you start in waste material and get a smooth transition. I saw Paul Sellers do this on one of his videos and it stuck with me as a clever way to get a clean start.
Good thought!! That comes up frequently and now I have an answer!
Hand plane or free hand cutting to line on bandsaw would be my two likely approaches with a preference for the bandsaw. If it's SPF lumber, a rip saw wouldn't be out of the question and likely faster than a hand plane. It would likely take no more than 10 minutes with a hand saw.