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Often I find myself fixing a failed rail of an arm chair or a part of a sofa that is inserted between plywood walls and holds the legs. Something like this, those red circles are butt joints where end grain of a front rail meets 2 sheets of plywood.

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Now because most furniture is made the way it is made 90% of the time that joint consists of a spit of wood glue with a few 2-3 inch staples applied from the outside that goes through the plywood into the end grain.

I work on location so repair needs to be quick and the joint is hidden so I am not planning to use any kind of joinery that requires hand cutting. But stability is of course a factor given the fact that often that railing is what the legs are screwed into and it being a chair.

Typical repair is remove the dried out dab of glue do a good application covering entire surface make sure it's a good fit and put in a few screw from the outside in to replace the staples.

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Now I realize that traditionally this is not a strong joint, but it does hold well (so does the Chinese dab of glue and a few staples to be honest since that's how 90% of factory furniture is made). But I would like to do my repairs as strong as possible.

So my question is, is it advisable to switch to pocket holes for this type of repair? Is there significant structural improvement? It is relatively quick to do and inexpensive.

I watched a few joinery overviews and my takeaway was that aside from cutting mortises which are not time feasible and a few other hand cut joinery the only 2 good fast and dirty options were pocket screws and Festool dominos (with dowels and splices performing about the same as just glue).

What threw me off was this video https://www.youtube.com/watch?v=ERXdLDudBnw

In which typical butt joint screws outperformed pocket hole screws like so:

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Is there an explanation of why that happened in this particular experiment? Is this an anomaly?

P.S. This post is about pocket hole screws and I want to keep it on point but as a follow up in your opinion does adding either metal corner braces or gluing in wood braces in the inner corner further improve stability? Or is it a waste of time?

Thank you!

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  • Who is the video from? It's best to name the source of a link (and in the case of YouTube the title ideally) when posting one because some people won't follow blind links, myself included. Sometimes this is for a very practical reason and in my case when I'm logged in I don't want YT to get the idea I'm interested in specific channels because then it'll deluge me with more suggestions from them (or the dreaded "People who watched X also watched the following") LOL
    – Graphus
    May 9, 2021 at 9:42
  • "Now I realize that traditionally this is not a strong joint" This is the first belief to challenge. We have a couple of related Q&As that relate to this (both glueing end grain | long grain joints and screws into end grain). Without going into any details, neither is as weak as almost universally believed! "I watched a few joinery overviews and my takeaway was ... the only 2 good fast and dirty options were..." Uh, through dowels??? Just blind dowels can match (or exceed) the strength of M&Ts! Again, we have one or two Answers here that touch on this.
    – Graphus
    May 9, 2021 at 9:51
  • Thank you for suggesting that option. Assuming I am putting in a 2x4 should I glue it in place, put in 2 screws towards the ends of the board and drill through the outside plywood into the center of the 2x4 endgrain to mallet the dowel in? Something like a 1/2 inch dowel?
    – Woodworking Devil
    May 9, 2021 at 17:21
  • Actually yes you can do that, but what I meant was standard dowel joinery, i.e. in the joint pictured above dowels would be used instead of screws. If glue and screws get the job done strongly enough then you could just go with them, I just wanted to highlight the quite startling absence of mention of dowel joinery in what you'd read/seen so far. In addition to how outright fast they are to do (equal to or faster than Dominos for example since you drill just one hole per dowel for both pieces of wood) they potentially yield the strongest joint poss; so they're by no means a compromise.
    – Graphus
    May 9, 2021 at 22:09

1 Answer 1

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I've seen other videos testing pocket screws, which also did not have them perform favourably compared to simple screwed butt joints. The primary benefit of a pocket screw joint is that the fixing can be hidden (depending on the application) - they are not a particularly strong joint. If the joint is going to be hidden or it otherwise doesn't matter what it looks like then there is never any reason to make it a pocket screw joint IMO. Just stick with what's faster, easier, stronger and doesn't require any special tooling, i.e. a screwed butt joint.

A bracket or braces should make the joint stronger, yes. It depends what kind of forces you're primarily trying to resist though. If you're guarding against racking forces (which you might be to some extent with a chair) then a wooden corner bracket will help the most, if it's simply the shear or straight-pull apart of the joint then I would think that a metal strap bracket like you've shown will give more strength.

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  • Thanks for the answer. When I was doing my research conventional point was that pocket holes are significantly stronger. Like in this thread reddit.com/r/woodworking/comments/ktsonb/… the most upvoted answer basically says that. Sounds that that is not always true and should be taken with a grain of salt.
    – Woodworking Devil
    May 9, 2021 at 5:07
  • Kreg states in their owner's manual that a pocket hole is mechanically stronger than a M&T joint. So various someones are doing something wrong, or Kreg are fibbing.... and given the litigious age we're in I'm pretty sure Kreg have solid data to back up that claim! Even if we want to be cynical and think they rigged their tests, I also know/know of a few professional cabinetmakers who rely on pocket-hole screws in various scenarios and one is confident to state that they compare favourably with blind M&Ts because he tested them and that's the result he got. [Disclosure: not a Kreg fanboy]
    – Graphus
    May 9, 2021 at 10:02

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