Table sawn coves are fun until it's time to clean up the profile. The hundreds of deep cross grain scratches will take hours to sand out. The right tool for this job is a gooseneck scraper.
I bought this one on sale last fall, this is the first time I've had the opportunity to use it. I began by jointing the edges square to the faces with my Lee Valley Jointer/Edger. This is a nice tool, but a shopmade jig can be easily made to hold a file square to the scraper or saw. I clamped the jointer in a vise, and used a rolling, sliding motion to joint the edge. I use an old bench for this type of work, I don't want metal shavings anywhere near my woodworking bench.
I then stone the edge on my 1000x waterstone. This soon wears a groove in the stone, rendering it useless for honing blades. I reserve one edge for scrapers only, and use different shims to avoid previous grooves. I use the same rolling sliding technique until the file marks are gone.
I then clamp the scraper in the vise and use my Veritas Tri-Burnisher to roll a heavy hook around the perimeter of the scraper.
I put on a pot of coffee, tune the radio to CBC, clamp the skirts between the dogs, and get to work. Tablesawn coves are notoriously difficult to clean up completely, a low angle desk light makes it easier to see surface flaws. I scrape the saw marks off, then refine the face with sandpaper wrapped around a rubber oscillating spindle sander drum. I work my way through 120, 150, and 180 grits.
From there it's to the tablesaw to rip off the ledge I made for the coving process.
It's now time to mitre the skirts to length. I use the mitresaw for this process. I start with the end skirts. First I trim off the best end.
I use the same spindle sander drum as a clamp pad. When mitering on the chopsaw a clamp must always be used, as the blade will want to pull your stock into the cut, making it inaccurate. I cut into the face of the skirt, so blowout is confined to the backside.
I clamp on a stop to cut the other end, making my end skirts the same length. I cut them so there is an inch reveal between the top of the skirt and the beginning of the roundover.
It's important to me that my side skirts have continuous grain across the two halves. I chop the full length stock in half, marking the mating parts.
This cut now becomes my reference end. I register it against a stop and mitre the other ends, making all four parts equal in length. They are also cut to a 1" reveal to the start of the edge profile.
Most people open and close their tables by grabbing the skirt and pulling. I warn customers against this practise, but I build for this type of abuse as much as possible. For strength as well as an alignment aid while glueing, I put a biscuit in the mitre.
I start by securing the skirt in my end vise. A mark is made 1" from the top of the skirt. The risk of the ends of the slot being exposed is high, so I skew it to top where it won't be seen.
I want the slot closer to the inside of the corner than the stock fence will allow, so I use transfer tape to adhere a 1/8" shim to it. I leave a small gap at the bottom so I can still see my registration mark. The fence is tipped to 45°, all the lock knobs are tightened, and I check to be sure I'm cutting for a #10 biscuit.
A STRONG WORD OF WARNING
Plate joiners are dangerous. The blade is hidden giving a false sense of security. I've seen a co-worker nearly loose a thumb to this machine. Always clamp your stock.
This procedure is paticularly risky because the point tipped screws on either side of the blade do not engage the stock. These screws resist the rotation of the blade. Because the blade does not have this resistance there is a tendancy for the machine to pull to the left. Do not have your hand beside the tool. Use your left hand to plunge the cutter, slowly so it does not grab. Your right hand secures the fence to the top of the stock. Do not wrap your fingers around the work piece, if the blade emerges from the other side you will be hurt.
That's as far as I got today, the afternoon was taken by a delivery. One of my favourite things about repeat customers is the opportunity to visit previous pieces in their new home.
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