Laying out and Cutting a Cove on a Box

[Ed Sallee]

Tonight, I got to the point where I was going to cut coves in the top & the bottom of a box that I have going on.... I know that before I've done a cove, I was curious as heck as how it worked. So, I figured I'd do a mini "what I did" sort of thing for anybody who is interested.

I did most of the grunt work on the box over the weekend. Made the box, lids, glued all together.... sanded a little and was ready to do the cove cuts tonight.

Not sure if it's the right way, but...it's how I do 'em....

First, I wanted the cove to be 1/2" at it's deepest point at 1-1/2" wide. You first cut a miter in a sacraficial fence, raise the blade to 1/2". Using your miter gauge, cut a kerf through the sacraficial fence.

Then, measure 1-1/2" from where the right hand corner of the blade breaks the plane of the table. Clamp the fence in place.

http://i302.photobucket.com/albums/nn88/evsallee/2009%20Project%2010/DSC08348.jpg

Then lower the blade to 1/16" and start your cuts. One side at a time - both top & bottom.

Keep on going up in 1/16" increments until you reach the mark that you previously made on the side, 1/2". Your cove should be 1-1/2" wide & 1/2" deep, as measured in the setup.

http://i302.photobucket.com/albums/nn88/evsallee/2009%20Project%2010/DSC08352.jpg

This works very well - but leaves some nasty saw marks that need to be sanded out.... I use a Forrest WWII 40 tooth alternating bevel blade on this cut.

http://i302.photobucket.com/albums/nn88/evsallee/2009%20Project%2010/DSC08359.jpg

About an hours worth of sanding with 120..... here is the result of my hour and half worth of work for the night......

http://i302.photobucket.com/albums/nn88/evsallee/2009%20Project%2010/DSC08374.jpg

Thanks for looking..... hope it didn't bore ya....

[Jerry Bruette]

Ed

Your posts of boxes and your how to's on making them amaze me. I should only hope to do work of that quality some day.

Thank you for unknowingly setting goals for me.

Jerry

[Jason Hallowell]

Great looking box! As long as it's safe and gets the job done, it's the right way to do it.

[Stephen Edwards]

Very informative. This post is a keeper for me. Thanks for sharing. Nice box, too!

[Mike Henderson]

Ed - I notice you mitered the corners of your box. Do you use a biscuit or spline or just glue the corners together?

Mike

[Ed Sallee]

Thanks for all the kind words....

Mike, I have put a vertical spline in the corners. It will be revealed when I cut the top off, then each time you open the lid..... I used walnut for the splines. See picture below

Also, I drilled the holes for the barrel hinges in to the back side of the box. So, when I cut the lid off, the barrel hinge holes will line up perfectly.

http://i302.photobucket.com/albums/nn88/evsallee/2009%20Project%2010/DSC08232.jpg

[Mike Henderson]

Thanks, Ed. Those are good ideas. One more question, if you don't mind. How do you cut the top off? Do you use a band saw? If you cut the top off on the table saw, do you have any problems with the "last" cut? I've been afraid I'll put a bit of pressure on the top and push it into the blade, rather than have it fall away. Also, the table saw blade is rather thick so it causes a discontinuity in the grain at the junction of the top and box - at least on mine it does.

That box you made looks very nice and has some nice design elements - congratulations.

Mike

[Julian Nicks]

Nice job. To help you out in the sanding department, I think you're using the wrong equipment. A gooseneck scraper will yield smooth results in much less time than it would take using sandpaper. It would probably only take a few minutes using a scraper, versus the time it took using sandpaper.

[Ed Sallee]

Mike.... When I cut the top off, I use the table saw and I leave the blade just shy of cutting all the way through. Somewhere around 1/32".... that keeps the lid on there throughout the cut.... and then simply use a box knife to finish the job..... I use the technique below to lightly sand after the cut. I use this on all my boxes to ensure a flat bottom/top.... I have a couple of boards with different grits.... (not the same box)

Yes, unfortunately, it will mess up the continuity a bit.... but, such is life. I will change to my thinnest kerf blade before making the cut.

Julian.... I would have preferred using a scraper, but the only one that I have is a card scraper.... Another good reason to make the trip to the store. Also, I'm sure if I used a 60-80 tooth blade and pushed it through slowly over the final cuts, it would have been a bit smoother. But, I don't mind sanding, etc.... keeps me from finishing up too quick and then I'd be looking for another box to build.... But, that's going to happen anyway. Can't stop the inevitable...but, I can prolong it :)

http://i302.photobucket.com/albums/nn88/evsallee/9.jpg

[Cody Colston]

Great looking box, Ed.

I'll second the suggestion to use a gooseneck scraper to remove the blade marks. For those shallow coves, the 3" spindle from an OSS works well for finish sanding, too.

Finally, a flat-top rip blade will leave a smoother surface when cove cutting than the Forrest ATB profile.

[Lee Schierer]

Nice technique. I have two suggestions. First, you need to get a zero clearance insert for that blade. Second if you change the blade to one with raker style teeth you will get a smoother cut and less sanding.
http://www.freudtools.com/images/LU82Mchart.jpg

[Mike Henderson]

Thanks for the pointers, Ed. I'll try that next time I make a box. I've been sawing the top off with a Japanese saw because it's thin (small kerf). I mark the line and then saw each side in turn. But I never get a really smooth cut so I have to sand the same way you do, and I get a discontinuity in the grain anyway.

I appreciate you sharing your knowledge.

Mike