Cove-cutting tips

[Victor Robinson]

I'm going to be cutting some large asymmetric coves (4+") on the tablesaw soon. I've been reading up on the subject and watching videos. I ordered a cove-cutting jig as well.

Are there any tips you veteran cove-cutters would offer? Is it possible to laminate stock if I can't find 6/4? Or would the glue lines be really bad?

Any ways one can really screw it up that I should watch out for?

Thanks!

[Brodie Brickey]

Victor,

How were you planning on cutting the cove? Table saw, Router?

I haven't cut large coves yet, but I've seen some woodworkers do it by feeding stock through the saw at a 45 degree angle with a progressively higher blade height. It strikes me as moderately dangerous.

[Chris Kelble]

I've cut cove nearly that large on my table saw several times. Make sure your fences (I use one on each side of the piece) are very secure and won't move on you while you are working. I use a 40 tooth full-kerf blade. Take small cuts (less than 1/16" at a time). Highly recommend you have a gooseneck scraper on-hand to clean up the profile after you are done. MUCH faster than sanding.

I would think if you laminate the lines would show up as pretty obvious. Probably depends on the wood species though.

[Cody Colston]

If you have to laminate, I'd do a test piece first and see how much the glue lines show up.

I use the TS to cove ogee-shaped bracket feet and the coves are pretty large. Since I make so many of them, I built an adjustable, angled fence that "straddles" my regular fence. I also made a jig to replicate the angle every time.

I only use that single shop-built fence across the blade which I tilt at 30 degrees for the ogee feet. I use my Forrest WWII, 40 tooth blade. I use pushblocks to hold the stock down and tight against the fence as I push it through and I raise the blade 1/4 turn of the handle on my 1023 TS each pass. I don't consider it any more dangerous that other routine TS operations.

Even with good dust collection, the process generates large amounts of coarse sawdust. You will probably need to stop the saw frequently and clean it off the top. Also, make sure you count the turns used to cut the cove to the desired depth so you can repeat it on subsequent pieces.

In addition to using a gooseneck scraper, the spindles from an OSS make good sanding blocks for the cove profile.

[Rick Potter]

1: I made some oak drawer fronts by laminating for overall thickness. Note that you don't need to laminate full thickness pieces. On mine I glued a narrow piece on one side, and a larger piece on the other. This way you don't have to cut through the full thickness of the center area. Mine were 6 or 7" high, and no glue line problem with red oak. I tried to match grain as well as I could.

2: Remember, the size of the saw blade changes the size of the elipse. I tried the 8" blades from my dado set, as well as 7 1/4" skill saw blades.

3: If using thin kerf blades you can double them up to get them stiffer, like on the skill saw blades, just make sure they are the same, and you stagger the teeth.

4: You can also try a molding head cutter with cove cutter heads.

5: If I remember correctly, the nicest elipse seemed to be with the blade tilted at 30 degrees, and the angle at 42 or 43 degrees. I can look it up if you need. Experiment.

Hope this helps.

Rick Potter

[Lee Schierer]

The latest issue of "WOOD" had an article on how to do this and how to determine the profile. I've used my TS for this once and it worked okay, it is slow as you have to make lots of passes to get to full depth. I would recommend a blade with Raker style teeth as they leave a flat top of the cut. Pointy teeth will tend to leave deeper score lines that are harder to clean up. Make sure you have everything secure and that you use a push block to hold the work down as it passes over the blade.

[Joe Scharle]

I've used this technique for a long time and agree with what's been said so far. I bought the Rockler jig and it does work a lot better than 1 or 2 boards clamped to the table. The overhead hold down is probably the best idea on the jig. It is somewhat unnerving when the workpiece cracks under your push block!
The angle is easier to set as well, and if you have an adjustable right triangle or large digital protractor, the angle can easily be set off the fence and a square piece of spacer scrap. I've also found some charts and calculators on the net by googling 'cove cutting on the TS'. With someone to pass the workpiece back, you can really speed up the work.

[Chris Kelble]

I've used this program a number of times. It will tell you the angle and height needed to get a specific cove. It will also draw a picture of the profile and print it out for you.

http://www.woodcentral.com/bparticle...html#downloads

I've seen a more sophisticated program once upon a time, but I can't recall where. It would allow you to do offset ellipse cove profiles and complicated profiles like that.

[Darnell Hagen]

Use a front and a back fence. The back fence resists the blade, the front supports the cove and prevents it from breaking if you push down too hard.

A molding head is your friend.

A gooseneck scraper is also your friend.

Keep an eye on the sawdust. It gets hot and where it piles up it has a tendancy to scorch your nice cast iron ts top. Don't ask how I know this.

If you can find stock big enough use it, but if not go ahead and laminate. The line will be no more visible than any other lamination. It's when you have a tapering cut through a lamination that the glue line becomes really visible. If you can, laminate them like Rick said, with a piece on the back that you don't cut into. In fact, the back could be a secondary wood if it is not visible in its final location.

Here's how I do it:

http://thewayiwood.blogspot.com/2010...d-profile.html

[Jamie Buxton]

If you're going to make only a few, a standard saw blade works. If you're going to make more, CMT makes a special cutter for your table saw. http://www.amazon.com/CMT-235-006-07.../dp/B000P4JP66

The standard saw blade leaves lots of saw marks in the cove which must be removed by lots of scraping and/or sanding. The wider curved teeth on the CMT cutter leave smaller marks that are much easier to clean up.