Chair repair

[Chet]

I have been asked to repair a chair.  I haven't seen the chair yet but they sent me a few photos.  I will see the damage in person this Wednesday.   It appears that the side aprons of the chairs were attached to the front and back legs using pocket screw and the screws have pull out if the rear legs.  My first thought when I saw the photo was to fill the area that the screw pulled from with epoxy and then replace the screw.  this concerns me though because if it failed once I would guess that it will fail again.  Or doing something with a domino.  The challenge in almost any repair is I have no idea what finish is on the chairs and because of this, doing sanding to clean up the epoxy or trying to use glue on a finished surface concern me. 

This is the under side of the seat.  You can see the screw protruding from the end of the apron on the right.

This is the rear leg section and you can see the tear out on the leg at the bottom of the photo.

 

[Tpt life]

For those screws to pull, I would question the screw choice or wood species. Two screws should hold 300 lbs. I am not sure I would have drilled the two so close together on one side of the apron.

 

Having said that, pocket screw butt joints? Anything more will aid a ton. 

[wtnhighlander]

Chet, my personal opinion would be to use the domino. Disassemble the parts if you need to for access. Painter's tape around anything that might get glue or epoxy. I'm just not a fan of screws in joints that see a lot of racking forces, like almost every joint in a chair.

Adding a screw as reinforcement is a different story. When the shank takes the force, rather than the threads, a screw should work well.

[Chestnut]

300 lbs of force is not nearly enough for that joint. An adult leaning against the back of a chair could easily put enough force against the back rest to pull those screws out. I'd do a loose tenon of some sort domino or otherwise. If your some what sparing with adhesive on the tenon and apply to both tenon and mortise you should get a good bond and won't have to deal with much if any clean up. Make sure to charge enough assuming your going to have to do the other 6.

The screws didn't get enough threads into the wood another fix that might not last as long would be to plug the screw holes and use a longer screw. In my mind a screw should have metal failure before the threads pull.

[Bmac]

That is just a terrible joint for a chair, pocket screws and a butt joint.

Domino might work better, but you will likely need to remove the screws near the break or your domino mortise bit may hit the screws holding on the side apron.

I would also consider adding a corner brace under the seat at each corner to supplement the repair, whether the repair is to re-pocket screw or domino.

Even with corner braces I wouldn't promise the world with the repair.

[wdwerker]

If it's possible to put a Domino in concealed coming in from below for the screw to bite into that might help reinforce the joint. Corner braces if they can be concealed would help too. Masking and scraping off any finish that's under the joint will help the glue stick & make clean up easier. 

[Coop]

9 hours ago, Chestnut said:

Make sure to charge enough assuming your going to have to do the other 6.

I’m betting that this is not a paying client but a friend of a woodworker. 

[Tom King]

That's what you call:  Designed to fail.    I wouldn't touch them.

[wdwerker]

I might repair it for a friend but not for a client.

[Chet]

13 hours ago, K Cooper said:

I’m betting that this is not a paying client but a friend of a woodworker. 

 

45 minutes ago, wdwerker said:

I might repair it for a friend but not for a client.

This "client" but not my client had the table and chairs built for her by someone out of Chicago.  I met this person (client) by doing a very very minor adjustment for them on a piece that was done by a fellow forum member.  The forum member had contacted me to ask if I would do this favor for him because I was about 1500 miles closer to her then he was.  Now a few months latter she has contacted me about this chair repair.  

[Tom King]

Here's a picture I just took of a strong, Walnut chair joint.   This is one of our kitchen table chairs, that came out of a factory that made school furniture 50 years ago-short story.  Notice that all legs have stretchers too.  Every one of those chairs is still wobble free, after being used for 50 years, and my Uncle that used them before us weighed over 350.