Tips on How to Correct a Loose Fitting Tenon

[JohnM Martin]

I know this probably never happens to any of you all :), but I let my saw wander a little too much when sawing a tenon for a roubo workbench build I'm working on. Now, the tenon fit is a little too loose for my liking; it's not off by a ton, but the joint comes together with pretty much no resistance, and won't quite stay together on its own. Given that I don't have the material on hand to make a replacement, is there a good way to "repair" this tenon to make it fit appropriately?

A couple things to note... This is for me and a workbench, so it doesn't have to be cosmetically perfect, but I don't want to have a compromised joint that will cause problems down the road. Second, I do plan on drawboring with 1 or 2 dowels. That should help with the holding power, right?

[Jeff Considine]

You'll probably get better answers, but I've used the cheek offcuts to glue back on the tenon cheek, then have another go at sizing the tenon from there. Since the tenon is not visible it doesn't have any cosmetic drawbacks.

[Kees Heiden]

Leave it, it's plenty strong enough after drawboring

[David Eisenhauer]

Jeff said it - glue some wood to the loose tenon face and trim it down to the correct thickness. Some folks glue plane curls to the cheek if they only need a few thousands and avoid having to trim it.

[David Myers]

What Kees said for drawbored M&T.

What Jeff said for glue-only M&T.

You are also now contractually obligated to show us your workbench when it's finished.

[Simon MacGowen]

Glue and saw dust! :D Just kidding.

Since you wanted tips...not just techniques:

Now, no jokes, bet you never heard of it: a piece of thick paper, if your fit is just tiny loose (that's the impression you gave). Thick paper is wood fibre, but thinner than a thin veneer which may be too thick for the gap.

Never tried the paper trick myself, but have been told repeatedly by those (good woodworkers) who did it that it really works.

Simon

[JohnM Martin]

What Kees said for drawbored M&T.

What Jeff said for glue-only M&T.

You are also now contractually obligated to show us your workbench when it's finished.

Thanks, all! Jeff, this is the only image I have so far... it is an in progress shot of working on the vise. It will have to do for now. Hopefully, I'll have more after this weekend.
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[sean contenti]

I'd just wedge the thing during glue up

[Hasin Haroon]

The best way in my experience is to glue an offcut on the tenon. But as Kees said, drawboring, (and the stress from the other joints) should get it nice and rigid.

[Jim Koepke]

Another vote for gluing on thick shavings or a piece of veneer.

jtk

[David Myers]

Glue and saw dust! :D Just kidding.

Since you wanted tips...not just techniques:

Now, no jokes, bet you never heard of it: a piece of thick paper, if your fit is just tiny loose (that's the impression you gave). Thick paper is wood fibre, but thinner than a thin veneer which may be too thick for the gap.

Never tried the paper trick myself, but have been told repeatedly by those (good woodworkers) who did it that it really works.

Simon

Business cards make good shims.

I've used them to help me determine which cheek of a tenon needs to be corrected.

And I'm pretty sure there's one in at least one in one of my drawbored workbench joints.

[Simon MacGowen]

Business cards make good shims.

I've used them to help me determine which cheek of a tenon needs to be corrected.

And I'm pretty sure there's one in at least one in one of my drawbored workbench joints.

So here is one independent verifier (we never met before right?) of the paper trick.

David C., if you are reading this, the ruler trick has company! :D

Simon

[Joel Thomas Runyan]

Depends on the size, type, and placement. Through mortise from leg to top? Wedge it. Housed from rail to leg? Draw boring and glue is likely strong enough. Loose enough to rattle? Glue more material on and plane down to fit. And all of that changes between 3x3 and 6x6 material.

[John C Cox]

How loose is it? 0.005", 0.030", or 1/8" too loose?

notebook/printer paper is about 0.003".
Veneer runs right at 0.020".

Glue 1 strip of veneer on 1 side to make up 0.020". 1 strip on each side for 0.040".

If it needs to stay centered - shave the tenon so it's 0.040" undersize and then glue a strip of veneer on each side.. Build up more as needed....

[Lee Schierer]

Now, no jokes, bet you never heard of it: a piece of thick paper, if your fit is just tiny loose (that's the impression you gave). Thick paper is wood fibre, but thinner than a thin veneer which may be too thick for the gap.

Never tried the paper trick myself, but have been told repeatedly by those (good woodworkers) who did it that it really works.

Simon

When making duplicate pieces or when wood turning a layer of paper is used to attach bowls to their lathes for turning or to hold multiple pieces together for sanding or trimming, and later the paper will allow the work pieces to break free without damaging the wood. In fact just this morning I watch a show where the woodworker was carving an Alpine horn and he used a layer of paper to temporarily connect the two halves of the bell while he shaped the outside. He was able to separate the halves with no damage. With that in mind I would think that paper in a joint would weaken the joint. Personally, I glue the off cut back in place and re-trim the tenon.

[Pat Barry]

I've seen paper used in a temporary fasion in a glue joint that you want to take apart. I would not use it in a glue joint I wanted to be permanent. I would much rather glue on a new face to one or both the cheeks and then recut the tenon. Drawbore itself would be great if you plan to disassemble the joint in the future, but, if its supposed to be permanent, I would definitely glue it.

[Simon MacGowen]

He was able to separate the halves with no damage. With that in mind I would think that paper in a joint would weaken the joint. Personally, I glue the off cut back in place and re-trim the tenon.[/QUOTE]

I have tried the paper joint in woodturning but not joinery work. However, I split the paper joint with a sharp chisel on the end grain and whether the joint would have held up in an enclosed M&T pocket is something I can't assert. Those who had done that were confident that they worked well. Perhaps someone could do a quick joinery test...paper thin gap done by fitting a tight joint and shaving off some to glue a paper.

Simon

[David Myers]

Threads here are definitely more similar to wildly figured woods than straight grained stuff freshly split from the log. They go in funny directions but are interesting.

For glue only joints where I've muffed the tenon I'll sometimes use paper shims to see which cheek of the tenon needs a glued wood shim (i.e. to the faces of the mating pieces flush). The shim is then sawn/pared to the fit that I should have achieved the first time.

I've only left paper shims in place on drawbored joints, which were also glued. You'd have to be really determined, and probably insane, to get those joints apart.

Side note: sometimes I'll unintentionally undercut the cheeks either from the saw or with careless paring with a chisel. I eventually adopted the router plane paring method and results are more consistent. And with more practice I occasionally do get tenons ready to go off the saw.

[Marvin Hasenak]

I use scrap or cheap wood veneer to fix my "training" mistakes with tenons.

[Jerry Olexa]

As Marvin said above....It will not "show"

[Brian Holcombe]

I would drawbore it and move on. :D

[JohnM Martin]

I would drawbore it and move on. :D

This is exactly what I did and seems to have turned out just fine.

[Art Mann]

I have used thick paper like a business card many times to repair loose M&T joints on antique furniture. It works just fine. I have never had anyone complain that their piece developed a loose joint. Using paper in this application has almost nothing to do with using paper in a temporary end grain application.

[Mark Rainey]

A gob of epoxy when gluing up?

[Prashun Patel]

Which way is it loose? I think it’s easier and stronger to angle these edges of the mortise and wedge anyway.

[JohnM Martin]

I ended up just drawboring it (as I planned anyways) and it turned out fine. Good to learn all the ways to fix it though. Thanks for all the suggestions. Here's my progress so far (with my helper) ...

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