Tenon rounding

Simple solution. Route mortices in both parts and make loose tennons. Rounded tennons for, say a 1/2" mortice, are made by cutting tennon stock to 1/2" thick to whatever width needed then rounding over the edges with a

BINGO! A good woodworker's rasp ($40 variety) is a remarkable tool. The cheapies at the BORG are not so good. Try Lee Valley.

Try FWW #172. Jeff Miller has a method that is so foolproof, you can use it for through tenons.

Get a strip of 36 or 40 grit sandpaper, a belt sander belt works fine, and do a "shoe-shine" on the tenon end that needs to be rounded.

Oops, I guess that doesn't count, it's not "mechanized" :)

Thanks ... and the web site let me see the article without kicking!

That sounds like it would work fine and provide the close-fitting profile I am hoping for in through tenons.

Bill

If I trim too much off the rounded parts, won't the joint be weak?

For a stopped tenon, obviously, appearance doesn't matter, but for a through tenon, appearance would be half the battle. In either case, I want the joint to be strong enough to outlast me.

I am enough older than my wife that I am planning cabinets that will, by design, outlast me by a wide margin.

Bill

Not really - since the ends of the tenons would be gluing to end grain (inside the mortise), which is very weak in comparison. The long-grain to long-grain glue surfaces on the longer cheeks of the tenon are where they get almost all their strength. Of course, for through tenons, it would have to be much tighter - I've avoided those so far. If I made them, I'd probably square off the mortises instead, as I think that would look better for most furniture styles (or stiles...). I'd also think about tapering the mortise very slightly, so the outer (visible) side presses tighter against the tenon. Oh, and for rounding off tenons, I usually use a fine hand saw to cut into the tenon corners flush with the shoulder, and then a chisel to split off the corners. Then pare down the remaining corners a little more until they fit. Good luck, Andy

With through tenons, I'll usually square up the routed mortise by hand. I've never liked the look of rounded-end through tenons, as much as I use them when they're hidden.

At one time or another, I've used most of the methods previously mentioned, rasps, chisels, even sanding blocks to knock the corners off the tenons. I care about the fit on the sides and ends of the tenon, and don't spend many seconds on the radius.

(yadda yadda)

Just posting to thank the group for giving me fresh perspective. Sometimes I get so focused on a problem that I kick the solution to the side so I can concentrate!

Here I was trying to figure out how I was going to get a router to (safely) round off the corners and the answer is to turn the router off and take a few swipes with just about any other tool ... rasps, sanders, handsaws, chisels.

The matter of rounded v squared tenon would seem to be an aesthetic judgement call. If I make the tenon a wedged tenon a little slop in the rounding process might actually work to my favor. Indeed, if I were to slit the tenon and drill an undersized hole, the wedging could be done with a dowel.

There seems to be some design potential here.

Thanks, guys. I think I'll go downstairs and play for a while.

Bill