Intro: Make a Router Planing Jig
No Planer/Thicknesser, or maybe it's not wide enough? If you have a router, then this router planing jig might be right up your street.
I built mine as an improvement over what I've used in the past to plane wide planks for waterfall tables. I estimate it halves the time to get the same job done as before - not bad for something cheap, easy, and quick to build!
Let me show you how I built and use it.
Step 1: The Options
Flattening and thicknessing a board, if you don't have a jointer/thicknesser (or one big enough), can be good exercise and fun with hand planes.
Less physical effort using a plain router sled, or a power hand plane.
But for speed and accuracy, a router sled on which you can lock two axes is the way to go.
Step 2: Build the Bed & Rails
All dimensions will depend on what size work you intend doing, so I give mine purely as an example
You need to prepare two identical, straight, parallel rails for the sled to ride on. I used 2"x4" lumber, and prepared both pieces, with hand planes
The base will be attached in grooves, which now get routed in each of the rails. I set the grooves so that there would be almost 2¾" below the sled - enough for the worst warped planks I'm likely to buy in the future!
The base is any flat, stable, sheet material. Cut wide enough to fit the rails and still have the planing width required
Attach the rails to the base with screws set at opposing angles. This 'dovetailing' will give more strength against the rails being pulled off
Step 3: A Sliding Sled
I used an off-cut of ¾" (18mm) construction ply for my sled. Something stiff and stable is what's required.
One side gets a two-wheeled bogey attached. The other side a single wheel.
The bogey chassis' are made from the same lumber as the rails, but ripped down by ¼" (6mm) so that it doesn't catch the ground.
Axle holes are first bored through, and then the spaces for the wheels made. For the single wheel bogey, which will be used to make a snug fit to the rails, the corners are removed as shown to expose most of the wheel
Wheels and axles are fitted, and the sled set upon the rails. Now the two wheel bogey is clamped and then screwed to one side of the sled. The single wheel bogey is attached with a pivot screw, and adjusted to pull all wheels into contact with the outside of the rails, before a fixing screw is added
Step 4: Attaching a Router
I chose to attach my router with a long rod through the parallel fence attachment holes on the router base. A single rod is all that is required
Fixing blocks for the rod were made in hardwood (beech). These are then attached to the sled, using screws so that it is easy to remove. The rod, together with the thumb screws on the router, give the router it's travel across the bed, and the ability to lock it in this axis for lengthwise routing
Stops are installed, which the router base will contact when the router cutter reaches the rails, preventing damage (you can see the limit lines I transferred from the rails to the deck to set these stops). Additional stops could be fitted to the sled deck, as required, to limit cutter travel within the work
Step 5: Finishing Steps
With the cutter installed (I'm using a ½", twin flute), a cutter access slot is milled through the deck
A hole for a dust extraction hose is bored through the deck. This seems to collect most of the finer dust, with the larger chips just being left around the work. So, no clouds of dust to breathe in!
I also added a scale to the deck, with divisions fractionally smaller than the cutter diameter. This makes stepping the router over after each pass a lot quicker and accurate. For a slightly better finish, step over half a division for each pass
Step 6: Using the Jig
Work Piece Fixing
The work should be held securely to the base
Wedges are used to support 'high' areas - stopping the work from rocking
Where there is sufficient waste material, either at the edges or ends, then through screwing can be used (counter bore clearance holes, so that screw heads lie below the final cutter depth to be used. This will prevent running into a screw by accident)
The work piece in the photo didn't have waste areas, so I used a fixing block each end, which was screwed into the end grain in non-show surface areas
The highest overall point on the work is found, and the router depth set to remove perhaps 2mm
The sled is then moved in a series of straight passes (advantage of locking the router base on it's rail), with each pass slightly overlapping. At the end of each straight pass, the router base is unlocked and slid across the deck by one division of the scale, before re-locking and returning to cut in the opposite direction. Once a full width has been completed, if required, the router depth is increased and the process repeated. This continues until the entire surface has been flattened
Same principle as for 'Roughing', except that:
Stepping over distance each pass should be reduced to less than half cutter diameter
Cutting should only be done in one direction (the one giving the best finish), returning the sled each pass before stepping the cutter across for the next pass
Cutting depth should be reduced to ½mm or so
Clear chips after each pass
Step 7: Finish Up
The results can be remarkably good, with little hand planing required to smooth the finished surface
The jig can also be used to:
Taper boards, by using a shim under one end. Compound tapers can also be done in a similar fashion
Run flutes, by installing a cove cutter
If you think of others, then please leave them in the comments
Free SketchUp Model
You should find a SketchUp model for the jig here, but if not, then it is available on my website in the 'Downloads' page (http://www.womadeod.co.uk)
You can see the video of this build here: https://youtu.be/Vy2VH9rKROs
Thanks for reading my Instructable!