While fitting arms to a rocker I am building, I pared down one side of the tenon a tad too far, and I had tenon that was too loose on side and too tight on the other. I did a little research and found a method that worked beautifully to fix this problem.

Since the tenon is the last part that is shaped in the arm, this means I've already invested a bit of time in the arm, so I was not about to trash it over a loose tenon. So I wanted to salvage the arm. I had my own ideas on how to make this tenon tight, small un-viewable wedges in the mortise, among other ideas, but this idea I came upon was absolutely brilliant.

 

Take note how loose the tenon is, then by eye use our block plane and round up a few shavings from it. The tenon below was shaped by hand, a combination of a hand saw and file, but one side of the tenon was had too much material removed. It looks pretty round, but when I fit it to the mortise, it was a horrible fit, especially after I tried to line up the arm with the front leg, it was angling in the wrong direction.

 

Apply glue to the tenon, then wrap the tenon once with the shaving you produced from the hand plane, trim it, then wrap it again, build it up oversize, this way you can always reshape it. In this case, I wrapped it twice, (in the image below the tenon shoulders are shaped, I worked the shoulders to where I needed them thus the reason why it's a different look than the image above. But it's the same arm.)

Trim the access off with a razor knife or other sharp implement of your choosing, and let it set.

 

 

After I let it set for just an hour, I was able to re-shape the tenon and get the tight, exact fit I needed. It was a great recovery from what I first thought was a nearly hopeless situation.

I wish I could quote or reference the source where I saw this fix, but in my haste to find a solution, I whizzed right through it, and out to the shop I went for the fix. I cannot take credit for this great idea, but I can show it off!

 

 

Now that's a neat idea!

 

I've used brown paper bag material to tighten up a rectangular tenon but yours is much better!

Lew, you could use this method to tighten up a rectangular tenon as well, any tenon for that matter. Haven't tried it but for this instance, but I have no doubt it will work for all cases.

I found this, a pretty good explanation at https://www.woodcraft.com/blog_entries/furniture-repair-tips

 

 

The one thing I disagree with on this image, is it appears the woodworker is wrapping the tenon over and over, this will produce an un-even lump where the layers overlap at the end and the begin of the wrap. You should do as I did, and wrap it once, cut it, then wrap it again, this way you are ensured an even build up of shaving.

take that to the bank...

I have done this and it works once glue sets just like the original wood even for turning. A second option is to fox the tenon , but only if the variance is very small

3 minutes ago, Gerald said:

A second option is to fox the tenon

Gerald, what does that mean, thanks!

A foxed tenon is when you cut a slot in the tenon and use a wedge in the end, but also on a foxed tenon the hole (mortise) is slightly wider in the very bottom. What this does is not only fill the space but creates a joint you cannot pull apart without cutting the wood or drilling tenon out. And no I have not done that but learned about it in one of Ralphs Wood quizes.

 

Another option is to cut off the tenon, drill a mortise in the arm, and glue in a piece of dowel.   Can turn/shape the dowel if needed.

I've seen this trick many times over the years and have used it a few myself.

 

1 hour ago, Gerald said:

A foxed tenon is when you cut a slot in the tenon and use a wedge in the end, but also on a foxed tenon the hole (mortise) is slightly wider in the very bottom. What this does is not only fill the space but creates a joint you cannot pull apart without cutting the wood or drilling tenon out. And no I have not done that but learned about it in one of Ralphs Wood quizes.

 

So it would have to be a through tenon?

55 minutes ago, kmealy said:

Another option is to cut off the tenon, drill a mortise in the arm, and glue in a piece of dowel.   Can turn/shape the dowel if needed.

That seems like a nightmare attempt Keith. Can you imagine getting a bit to go in perfectly to that arm, so that after the dowel is inserted, the angle the dowel needs to be at, would be dead on alignment for the arm to meet up at the front leg after it's inserted into the rear leg? Since the arm is skewed, and the square reference is gone, to get that dowel in at the precise angle, whew, makes my head spin just thinking about it. Plus, drilling out the hole in such a slender form, you also risk cracking the arm narrow. It sounds solid, but after ya think about it, the execution would be a nightmare.

48 minutes ago, John Morris said:

So it would have to be a through tenon?

 

no...

use a single double tapered wedge...

use this pic as a an idea former...

 

 

these legs are set up for single wedge wedged fox tenon...

 

 

here's w/ a double wedge... (cut away)...

this joint won't come apart...

 

Edited March 13, 20179 yr by Stick486

Great tip John and others too...just another argument for a Tips & Techniques forum...

26 minutes ago, Grandpadave52 said:

Great tip John and others too...just another argument for a Tips & Techniques forum...

+1 

13 hours ago, John Morris said:

So it would have to be a through tenon?

No usually used in non-thru tenon, but could be used on either

12 minutes ago, Gerald said:

No usually used in non-thru tenon, but could be used on either

Looking at the diagrams here in this topic Gerald, I like it, thanks for opening that idea up here, appreciate it much, always learning! Love it!

9 hours ago, John Morris said:

Looking at the diagrams here in this topic Gerald, I like it, thanks for opening that idea up here, appreciate it much, always learning! Love it!

there is a special cutter that creates a cone shaped hole for this tennon style also. I'll try to find a link

http://www.rockler.com/tenon-lok-dovetail-drill-bit

here it is

47 minutes ago, John Hechel said:

http://www.rockler.com/tenon-lok-dovetail-drill-bit

here it is

Oh now that is cool.

I like it John, thanks.

All that being said, the wonderful thing about the post and rung chairs, especially in the shaker fashion, they are easy to repair, if you get a busted rung, you can knock the legs down and make the repairs, they planned it that way. Problem with that joint, you aint knockin nuttin apart!