A Simple Router Sled to Flatten Walnut Live Edge Slabs

[jteneyck]

I have some walnut slabs that I'm going to turn into an island counter top for a friends ski chalet. First, thanks to Ken Vick for helping me schlep them out to the drying bunks last Fall. I'd thank the neighbor kid for helping me get them down into the basement and into my drier, but he's not smart enough to hang out here. Now that they are pretty dry I wanted to start cutting them to rough size and do some initial flattening.

After cutting one of the 8/4+ thick slabs to rough length of about 56" I made a simple router sled from a couple of 2 x 4's that I jointed straight and ripped parallel. I laid them on my bench and connected the ends with a couple pieces of scrap plywood and screws. I put the rough slab inside and shimmed it with a couple of shims so it wouldn't rock. I made the router sled from some scrap 1/2" and 3/4" plywood, screwed together. It's 2x+ longer than the width between the 2 x 4's so that it can slide from side to side. A cleat under each end keeps the router bit from cutting into the 2 x 4's. The router is held to the sled with 3, #8 machine screws through holes in the router base. That's it. Took all of an hour to make.

Here's a photo flattening the first side.



I had to make two passes, taking off about 3/16" total, to get it flat most everywhere.



I flipped it over and did the other side. Only took one shallow pass to get that side pretty flat everywhere.



It took about 90 minutes total; a little slow using a 1/2" straight bit. Two more slabs to go, then I'll let them sit for a few weeks before further work. Might have to modify the sled to incorporate some dust collection because it sure went everywhere. Anyone have any clever ideas? I'm thinking a flexible shroud around the bit with a port for a hose.

John

[Ken Vick]

Boy, John, that slab sure looks good. Any reason you had to do the leveling in your basement? I would have done that in my driveway. I can imagine the dirt and dust from taking 3/8" off that big slab. And Walnut dust, to boot. Ken

[jteneyck]

Mass, Ken, mass. The thing must weigh close to 100 lbs. No way I'm carrying 3 of them upstairs to flatten, then back down to join, etc., then back up again when it's all done. You garage shop woodworkers are blessed - in the Summer anyway.

There was some dust, but not as much as you might think, or maybe it just blended in with all the rest. There sure were a lot of chips though. I'm going to give some thought to a dust collection system before doing the next slab. I think I have an idea on how to go about it. More on that later if it works.

John

[Stwood_]

Looks great. They make a flush cutting bit that works well for that. It's 1-1/4 wide. Used mainly for flushing up solid wood to plywood.

I can get that bit number tomorrow.

[ianab]

The router tends to throw out pretty coarse dust / chips that just fall on the floor, easy enough to sweep up. Not like fine dust from sanding that likes to float everywhere.

But the idea works pretty well.

[David G]

Thanks for this and all of your other "how to" posts. I always learn something from your efforts. Much appreciated.

[bennybmn]

jteneyck said:

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Might have to modify the sled to incorporate some dust collection because it sure went everywhere. Anyone have any clever ideas? I'm thinking a flexible shroud around the bit with a port for a hose.

John

---

20" box fan with a filter at the end of the bench blowing away from you to catch some dust? Anything you can rig up that will actually collect the big chips is going to be too bulky I would think. Maybe a hose with a port screwed to the plywood carrier pointing right at the bit, depending on how much room you have between it and the work piece, but even then it will depend on which way the bit is entering the wood relative to where that hose is, it could shoot the chips in the opposite direction, ya know?

[Dan Moening]

Really nice work, John.


I think you could attach a "dust skirt" to one side of the sled to aid in containing the chips. Then attach a DC port to the other side with a "dust skirt" covering the remaining open area of the sled.

If you find a "dust skirt" that is flexible enough, it would ride over the 2x4s but still press against the slab.

Here's an a homebrew CNC dust collection to get the idea:


Easy-Cut Strip Brushes at Mcmaster-Carr:
http://www.mcmaster.com/#conveyor-brushes/=ynwou7

[jteneyck]

That's exactly what I was thinking of Dan. I remember seeing similar arrangements as your picture on industrial CNC machines. I didn't have any brushes this AM, but I came up with something of similar concept using some thin door seal before I milled the next slab. I don't have much clearance between the slab and bottom of the router sled.





What you see lying loose is what it didn't catch, and those are chips; it got nearly all the fine dust. I had to empty the shop vac and it was half full again when I was done. Because I'm only cutting with a climb cut, all the chips go towards the dust port. I think it probably captured 80 - 90%, and with a brush seal like in your photo I think it will get nearly everything.

Thanks.

John

[bennybmn]

Nice work! I've worked with those brush strips linked above (have some sitting next to me right now actually). Very easy to work with, let us know how you make out.