Plane Your Wood Slabs With a Planing Sled That You Build





Introduction: Plane Your Wood Slabs With a Planing Sled That You Build

This instructable gives an overview of how to plane your wood slabs flat using a router and a Planing sled.

Step 1: Start With Your Wood Slabs.

Here are the two wood slabs that I want to plane flat

Step 2: Measure Your Wood Slabs Maximum Width and Length.

These wood slabs are on the smallish side. So I wanted to plane them together and match up the thicknesses. I figured I would make a planing sled that accommodates one large slab.

Measure the maximum width of the slab and the maximum length of the two slabs together.

I came up with 19" x 65"

Step 3: Figure Out the Maximum Thickness of the Slab

Now find the maximum thickness of the slab.

You can now design your sled to accommodate for this.

(I noticed after making this Instructable that most slabs are 4" or less in thickness.)

Step 4: Measure Your Router and Router Bit.

Measure the diameter of your routers base, and the diameter of the router bit that you will be using.

This determines the inside dimensions of your router sled and the hole that the router bit fits into.

My router base was 5 3/4" and the router bit was 1 1/4 ".

Step 5: Construct Your Sled

Take your dimensions of your router and bit and apply it to your sleds dimensions. The router base was 5 3/4" so I made the inside width of the sled 5 7/8" The router will fit into this with an offset of 1/8". I also made the hole for the router bit 1 1/2" wide.

Step 6: The Sled Assembled

Here is a photo of the sled. The first photo is the sled upright and the second photo is the sled flipped over. The sled has a flat base except for the two overhangs. This keeps the sled aligned on the rails while you slide it laterally.

Step 7: Build the Box With Rails.

Take your maximum width and length of your wood slabs and basically build a box for it. The rails must be parallel and square. this is the reference for the sled. Also make the rails tall enough to accommodate the maximum thickness of the wood, in this case 4 inches, plus the thickness of the sled which is 3/4 inches, plus another 3/4 inches of "air" for your safety plane.

Step 8: The Sled Base, Sled and Router.

here are photos of the sled base, which you will drop your wood slab into, the sled atop the rails, and the router placed into the sled.

Step 9: Place Your Slabs Into the Sled Base

this is what it looks like after I place the slabs of wood into the sled base.

If the bottom of your wood slabs do not lay flat in your sled base, you can use shims and wedges so that they don't rock.

the final step is adjust the router bits dept so that i barely touches the highest point of the slab. You want to take off about 1/16" of wood at a time.

Step 10: A Little at a Time

you can see how much wood I take off for each pass.

Step 11: Start Planing

Start planing on one side and work you way to the other side. back and forth, right to left or vice versa.

and always wear your Personal Protective Equipment! PPE's

Preserve your eyes, ears and lungs!

Step 12: Heres the Planed Surface

And here is a photo of the planed surface. its now perfectly flat and now needs a sanding in the direction of the grain.

Step 13:



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29 Discussions

Not to detract from the author's accomplishment, I made something similar using inexpensive linear bearings and guide rails from ebay. I had a 6" slab from a 30" stump. No way was I going to hand plane or belt sand both sides of this slab. I incorporated a positive stop on the longitudinal slide so the router didn't go wandering about as I cut thru the annular rings. I used a carbide cutter and as the author I made minuscule cuts to lessen the impact on the router when encountering the high areas. I actually started out using a tool steel fly cutter. The wood rapidly dulled the cutter bit and I was forever sharpening it. That's when I moved onto carbide.

1 reply

Was there any movement from the slabs when planning?

Great job make me one as soon as possible!

Can you tell me what bit you're using?I'm going to make this soon

Does anyone have an idea on how to add adjustable height to it? Preferrably without making new frame for each wood slab :)

2 replies

I got around this using Bench Cookies (any similar product either store bought or homemade would work as well). I had a slab that was too large for the sidewalls on my rig, so I drilled some holes into my work surface and added some threaded plugs (You could use hanger bolts, but you wouldn't have as many height options with that approach). I then added threaded dowels and used them to mount and elevate the bench cookies to a uniform height and placed the rig's frame on top of the bench cookies ( I used 12 to ensure uniform support).


Your hand router has an adjustment for your bit height. Therefore you do not need a new frame for each slab.


Did you build two sleds for the router? If so, why two?

As for how to keep the workpiece from moving around... use a few pieces of double sided tape on the high places of the bottom of the board. don't use the foam type of tape it is not guaranteed to be the same thickness because the weight of the board may or may not press it flat instead use the flat type of double sided tape.

Just a thought on this great Sled.
It should be possible to use an electric planer and adjust the sled making part to fit? You could still adjust the planer from above and take thin slices. I'll have to work on that one when my workshop's finished.

Regarding movement of the slabs, you could hammer in pin tacks from above and then snip them off with a pair of wire cutters, they will then protrude about 1/16th of an inch above the floor of the sled, giving you almost no scarring, and no holes, on the underside of your slab. Great 'ible too, by the way!

A very interesting adaptive approach to planer. I dont know if you have seen for sale the electric hand planers. Here's an example: I used one to roughly plane an entire room of wood floor. It takes off a wide strip at a time but without some type of jig the total planed surface will not be perfect. The router planer gives very impressive results. If I could figure it out I would try making a simillar sled for my electric hand planer.

2 replies

I had to refurbish four bedroom floors, and after doing some tests on their closet floor (that have the same wood), I ended up doing only one bedroom with a variable speed belt sander, 3"X21"... While doable, it was slow and tiresome, but the results were very good. Then I rented a profesional belt sander (a HUGE one, that has a 12" wide belt and weights 75 Kilograms!). I spent about a fifth of the time that I would have needed if Ihad insisted in using my hand belt sander, and it was way easier because this large machine has a large handle bar that allows you to push the machine when walking across the room, avoiding the need to be on your knees as with the hand belt sander. In any case, a belt sander gets a much better leveling compared to a planer when the surface is large, like a floor of an entire room. Amclaussen.

I agree that a sander is a more ideal finishing tool. A power planer is much different than a hand planer though, it works completely differently. A hand planer you push along like a knife. I tried a hand planer at first and it chewed up the floor really bad. A power planer has a rotating drum. If you need to remove more floor than a coarse sandpaper can take away, a power planer is very fast, very good. I tried a belt sander, a regular one with coarse paper. The floor was just no one close enough to smooth for that to even be useful.
The walking professional floor planers and sanders are the dream but outrageously expensive to buy and not cheap to rent.
Even taking as much as an 1/8 inch of floor off in spots, my floor is still nowhere near level. Smooth yes but not level. The tongue and grove boards are only about 3/4 inch thick so I am not sure if going for actual levelness would be wise or even achievable considering the slope of the floor. The poor old house. It doesnt help that for plumbing and furnace installation over the years, the people doing the work decided it was somehow ok to cut through the main, original, largest support beams of the floor to make their work easier. My dad did what he could adding in posts to the basement by jacking up the house with bottle jacks.
The power planer still is overly aggressive and left some tear out in the floor. Im still not happy with the floor. I dont think I'll be able to keep the original floor only. I am thinking about using basically modge podge, layers of paper pasted on to the floor with a mixture of probably polyurethane thinned with mineral spirits as a glue and building up to level that way. I know most old house have some sort of slope to the floor but to me that is not ok. I want to be level.
Thank you for the comment. You are right. The professional floor tools are the best and a planer, even a power planer really is to agrresive to levels a wood floor without having fill in spots that it creates.

How do you keep the slab from moving around so you aren't chasing a moving target.

2 replies

The times that I've done things like this, I used screws, either into the edge of the piece (and then down into the table) or up through the table and into the workpiece.
So long as you keep track of the location of the screws, and don't hit them with the cutter, the only downside is that you end up with screwholes.

"you can use shims and wedges so that they don't rock."
And, you can use a bit of HotMelt to secure them to the base and slab to prevent unexpected movement.

As well, one might secure the router to the trolley so that the same jig could be used to cut with the grain, move the router the diameter to the bit, re-secure it and make another pass.

Excellent instructable. I was wondering if you need some way to secure the wood during the process. I guess if the slab is big enough, you may not need to, but I would worry about the wood moving around especially if it is resting on shims. Great idea though. I also think that e-spiv's suggestion of making a longer sled to go with the grain would be a nice addition. All you would have to do would be to make a beefier sled with taller sides. I think it would speed up the process significantly since you would only have to move the sled a few times.