Tenons on a curved rail

[Joe Cowan]

I am building a bow front hall table. I have laminated the two piece front and have done takeoffs from my full scale drawing, and now I need to cut the tenons. I guess I will eyeball a bandsaw cut and sneak up to the line with chisels etc unless someone can point me in a more logical path. Each section of rail is 18" long by 7/8"x 3 1/4".

[John TenEyck]

I would cut mortises in the ends of the rails with my horizontal router mortiser and use loose tenons, but you likely don't have one or may just prefer integral tenons. In that case I would make a little sled to hold the part on my bandsaw at the correct angle. The sled would slide along the fence. A spacer between the sled and fence would give you the offset you need to cut the other side of the cheek.

John

[Rod Sheridan]

I cut those with a jig on the shaper. It cuts both cheeks and shoulders at once.....Rod

[Jim Dwight]

I would also use loose tenons but I would cut the mortises with my domino. Without one, I'd probably use a plunge router to cut the mortises. But roughing the tenons with a hand saw or bandsaw and paring to size is another option. I like to use my shoulder plane when possible.

[Joe Cowan]

I would cut mortises in the ends of the rails with my horizontal router mortiser and use loose tenons, but you likely don't have one or may just prefer integral tenons. In that case I would make a little sled to hold the part on my bandsaw at the correct angle. The sled would slide along the fence. A spacer between the sled and fence would give you the offset you need to cut the other side of the cheek.

John

I was thinking I would make a bandsaw sled and do as you suggested. As each piece is curved, it is hard to reference off of a fence etc, so a certain amount of eyeballing will be required. I thought about using my Domino and may still try to use it.

[Derek Cohen]

I am building a bow front hall table. I have laminated the two piece front and have done takeoffs from my full scale drawing, and now I need to cut the tenons. I guess I will eyeball a bandsaw cut and sneak up to the line with chisels etc unless someone can point me in a more logical path. Each section of rail is 18" long by 7/8"x 3 1/4".

Joe, I would not eyeball it. Instead, draw the table as a plan on a sheet of MDF, and then you can accurately draw in the tenons. Now cut this up to use as a template so that you get the angles of the tenon correct.

http://www.inthewoodshop.com/Furniture/SofaTableAprons_html_4519e2c5.jpg

You can saw the tenons with the bandsaw. I would use a backsaw ....

http://www.inthewoodshop.com/Furniture/SofaTable-Legs_html_297c2291.jpg

http://www.inthewoodshop.com/Furniture/SofaTable-Legs_html_3ea4a33c.jpg


http://www.inthewoodshop.com/Furniture/SofaTable-Legs_html_m67e43632.jpg

Mortices with a router, squared with a chisel ...

http://www.inthewoodshop.com/Furniture/SofaTable-Legs_html_5daaf5c.jpg

Ends like this ...

http://www.inthewoodshop.com/Furniture/SofaTable-Legs_html_m430bbf06.jpg

Regards from Perth

Derek

[Joe Cowan]

After sleeping on it, I think I will use my Domino. The issue before was the curve on the ends was so severe, I did not have enough meat to allow for a domino as the cut would go completely through the rail. I will clamp some laminations in the form and make a matching backing board to glue onto the back of the rail (at the end) to give me enough material to accomplish this. This is adaptation of a Norm plan and I made the curve much greater and now am scrambling on the the "how to" part. Thanks for all the suggestions.

[Jim Becker]

That sounds like a good plan, Joe. I do agree with Derek that drawing it out full size is a good idea so you can be absolutely sure with your placement of the Dominos for the reason you mention. I burned myself on this on a project I'm about to post about...a small miscalculation that resulted in having to execute some "craftsmanship" to fix.

[Joe Cowan]

That sounds like a good plan, Joe. I do agree with Derek that drawing it out full size is a good idea so you can be absolutely sure with your placement of the Dominos for the reason you mention. I burned myself on this on a project I'm about to post about...a small miscalculation that resulted in having to execute some "craftsmanship" to fix.

The first thing I did was draw the pattern on a sheet of MDF. I am taking all measurements off of it so far. Now I am making a small sled for my bandsaw to cut the ends of the rails to length. I will use my edge sander to tweak it if necessary.

[Jim Becker]

Jigs and fixtures are the best way to handle so many things when they are not flat and square. :D

[Dave Cav]

I had to make some small chairs with curved horizontal slat backs. I used 8/4 stock, used a template to lay out the curve on the top edge, cut the tenons on the tenoner, then bandsawed out the curves.

[Bruce Wrenn]

Dowels have been used in this application for hundreds of years. Build a jig to hold plunge router perpendicular to end cut, and drill with plunge router. "KISS" principle.

[Thomas McCurnin]

I bet Paul Sellers could knock out a couple of those tenons in 30 minutes or less with nothing more than a saw, marking knife, and a chisel. I remember taking a class from the school in Texas where he once taught and they had like three rules written on the black board which we had to recite every morning: (1) Cut to Waste Side of the Line. Always Leave the Line, (2) Always Form Knife Walls, and (3) Bevel Down for Mortising. I loved that class, miss the instructors.

[William Hodge]

The mortise can dictate the tenon design.

I make the mortise in the stile square to the table.

The tenon needs to present shoulders and a tenon that are in line with a tangent to the arc of the rail.

When the rail goes into the stile, the shoulders hit the stile square, and the tenon will follow the mortise.

I cut these with a tilting table on a tenoner. If I didn't have a tenoner, I would use a sliding table on a band saw, and cross cut the shoulders on a sliding table on a table saw. The concave side down can be complicated. I make a curved base for concave parts to sit on, in order to reference the curve, not the ends.

The math is less complicated than it sounds, given that the stile is cut square to the table.

A problem arises when the stile does not follow the arc of the rail, being flat. The wider the stile, the greater the deviation. On a 2" wide stile, a slight rail arc requires a few swipes with a hand plane. Smaller diameter rail arcs can result in having to use thicker stile stock, and cut a curve on the faces of the stile with convex and concave shaper knives, 2 1/2" tall.