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$10 router bit set does bead, cove, and planing
By:Paul G. Jacobson
Date: 2/25/2000, 9:22 am

Sears has an inexpensive ($9.99 US) starter set of router bits with a part number of 9 29021. My current poject is modifying these inexpensive bits to cut bead and cove edges on my strips.

The set includes a 3/8 bead/corner-round bit which I hope can be easily modified slightly with a grinder or a file to give you an inexpensive tool for making your bead and cove cuts.

The shape given with most commercial bead and cove bit sets is a semicircle with a radius of 1/8 inch. This is the smallest radius that can be made which will cover the thickness of a 1/4 inch strip, and I think this is a bit too much. A larger radius cutter would cut shallower and still give the nice mating edges, which bond well, when the strips meet at slight angles.

(There is no reason why the radius could not be 1/2 inch or more. As the radius increases the edges of the strip approach being straight, so radiuses over 2 inches are barely there. I think the practical upper limit is about an inch.)

The 3/8 inch radius of the bead-cutting bit mentioned above is a shallower cut than the usual 1/4 inch radius, so less wood is removed (more strip = less sawdust) and when it is mated with a bead that has the same 3/8 inch radius you get a joint that should work just as well.

This cutter makes only half of the bead. You will have to flip the strip over and run it through the router a second time to complete the bead. This is not difficult, or particularly time consuming.

Since you have a single bit with the profiles for cutting bot the 3/8 inch radius ead and cove, you selet which cut you want by simply adjusting the height of the cutter and the location of the fences on your router table. Be careful not to get your fingers near the cutter when the router is on. When the cutter is aligned to cut the coves a part of the cutter is above the strip. It should be partially hidden by the fence, but still: be careful.

I have a webpage with some pix and illustrations of how I plan to go with modifying this bit. This is a 2 wing cutter ( it has two cutting blades) and I have drawn over one of the cutter edges to show how it cna be modified. Of course you will need to file down both cutting edges.

The 1/4 inch straight cutter that comes in htis set can be used if you want to use your router and router table to 'plane' your strips to an even thickness. It has a straight cutting edge that is 1 inch long, which should be sufficient for 3/4 inch wide strips.

Set your fence away from the cutter to give you the strip thickness you need and feed the materials slowly to get a smooth cut.

If you want to stick with the 1/4 inch radus commonly used on B&C strips you can cut the coves with the 1/4 inch veining bit. Be sure to get a solid set up wiht your fences and feather boards so the strip does not wander around, and feed it slowly. You may get better results by making two passes, cutting a shallow cove and taking off about half the wood on the first pass, then adjusting the cutter to complete the cut and making a second pass. You can make a fair bead with a hand plane, or, cut the bead with the 3/8 bead cutter (two passes) to get it close to the desired shape, and use sand paper or a hand plane on the bead to get a tighter fit.

Use the veining bit to cut a slot 1/8 inch deep in a 6 to 12 inch long block of 2 x 4, and then line that with medium grit sand paper, which you can staple to the sides of the block. This will give you a shaped profile sanding block that can be used to touch-up the beads on strips that are trimmed or narrowed.

Hope this helps someone. Obviously similar router bits can also be modified, and I suspect that you can find inexpensive ones for less than this set. Go for it!

Paul G. Jacobson

Messages In This Thread

$10 router bit set does bead, cove, and planing
Paul G. Jacobson -- 2/25/2000, 9:22 am
Re: $10 router bit set does bead, cove, and planin
David Koslow -- 2/26/2000, 10:56 am
They told Orville and Wilbur it would never fly
Paul G. Jacobson -- 2/29/2000, 9:06 pm
Re: They told Orville and Wilbur it would never fl
David Koslow -- 2/29/2000, 10:57 pm
Re: $10 router bit set does bead, cove, and planin
Bruce -- 2/25/2000, 10:31 pm
Re: $10 router bit set does bead, cove, and planin
John Michne -- 2/25/2000, 3:24 pm
Caution !! Mod. to High Speed Bits
Rehd -- 2/25/2000, 11:24 am