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I've come across two schools of thought for gluing dowels in place.

  1. PVA wood glue, such as Titebond.
  2. Two-part epoxy, such as Araldite.

Bearing in mind long-term stability, which is preferable for interior door hinges?

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    I have always wood glue but usually use match sticks or toothpicks depending on hard wood or soft wood. – Ed Beal Oct 14 at 18:47
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    As does Ed, I've always used a quality wood glue. Wood glue actually soaks into the wood and dries slowly, creating a strong bond (with matches or toothpicks). Epoxy doesn't have time to soak in because it dries faster due to the chemical hardening. – JACK Oct 14 at 19:00
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    Have a good read of : diy.stackexchange.com/q/171241/97780 – Solar Mike Oct 14 at 19:37
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    As JACK said, the epoxy will create a CHEMICAL bond which in this case is less reliable than the MECHANICAL bond created with quality wood glue, adequate clamping and proper curing time. – M.Mat Oct 15 at 1:05
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    @Jasen if the holes are badly stripped longer screws won't help for long. There's too much leverage on them unless you can go longer and fatter – Chris H Oct 15 at 8:40
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Wood glue, hands down. Wood glue is designed to penetrate the wood for a tighter bond. Properly done, wood glue is stronger than the surrounding wood. I have chairs I've wood glued and clamped and they're still fine years later.

Epoxy is OK, but you have to make sure you get the right epoxy too. Many are exothermic (they get hot) and might eat your wood. Just be sure to read labels for supported materials.

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    Regarding epoxy, Matthias Wandel did some glue strength testing and notes My epoxy joints in spruce were significantly weaker than the wood glue joints, and even weaker than the hot glue joints. Based on this, I decided to skip the epoxy glue for my tests with hardwood – hlovdal Oct 15 at 7:25
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    The difference in strength is unlikely to be important. The big advantage of wood glue is that it's just easier! You don't need to measure and mix it, and you clean up the excess with water. Cheaper too. – Robin Bennett Oct 15 at 11:40
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    And for this usage, you don't even need to wait for the glue to dry. Once the dowels (or toothpicks etc.) are trimmed flush you can go ahead and drive the screws. I see no reason to use epoxy here. – JimmyJames Oct 15 at 14:06
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    @hlovdal Anyone who makes weaker epoxy wood joints than hot glue joints is too incompetent to be gluing anything. – Kaz Oct 15 at 20:13
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    @Kaz I assure you Matthias Wandel is quite competent. I don't remember specifically his comments on epoxy, but I remember his glue joint tests, and they were very well designed for someone using readily available parts to make his testing rig. He used to be an engineer for Blackberry before he started earning good money selling plans and making videos for YouTube. – Bloodgain Oct 15 at 22:03
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Wood glue, always. Sandpaper the dowel and hole to give a better surface for the glue to hold.

  • Hello, and welcome to Home Improvement. Thanks for the answer; keep 'em coming. And, you should probably take our tour so you'll know how best to contribute here. – Daniel Griscom Oct 15 at 15:49
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Wood glue works well; when cured it can flex a little as can wood itself. Epoxies tend to be rather brittle.

Epoxies vary a lot: slower epoxies (e.g. Araldite Precision) are (i) much less exothermic, and (ii) liquid for long enough to soak in a little. They need the parts to be held stably together during curing. They should be stronger than fast epoxies in this application, but they're still not as good as wood glue.

The key to a repair like this though is to pack the hole well, so you're not relying on the glue to take the weight, just to keep the joint stable.

  • There are so many epoxies, you can't generalize. Some have a variable mix rate of hardener from 1:1 to 2:1 (flexible to hard). The curing times vary greatly. Some harden in five minutes, some take hours. How well epoxies "wet out" a material varies. (e.g. an epoxy that is designed for cloth laminating work in hot weather will have good wetting properties and a long working time.) – Kaz Oct 15 at 20:26
  • @Kaz, that's true, and I've used some that didn't cure at all until heated, but I was only considering those that are commonly sold for domestic use, and made up according to instructions (even common ones cab be accelerated a little with extra hardener, but possibly at the expense of strength) – Chris H Oct 15 at 20:29
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Wood glue, but not for the reason why you ask. In terms of long-term stability, the observable difference is exactly zero. There is no force acting on the dowel, and there is no exposure to water to be expected.
You could probably stick the dowel in with a bit of spit and dirt, and it would do. Still wood glue is the correct thing to use.

Wood glue is non-toxic, easy to handle, and it works very well for wood. In fact, in absence of water, it is one of the best choices for wood (unsurprisingly) rivalled only by polyurethane (which is much more expensive and somewhat on the toxic side). Wood joined with wood glue, even when done with bad skill in unfavorable conditions, usually holds forever, or until the wood breaks to pieces, with the glue still intact and wood splinters protruding from it.

Epoxy, on the other hand, is vile chemical stuff that certainly has its merits where you need it (above all, it's waterproof and insensitive to most chemicals, plus it can also be used to "fill holes", give smooth surfaces, etc.), but it is uncomfortably sticky shit that spoils everything and anything it comes in contact with, and by no means as easy to handle as "open screw lid, use, close screw lid". Plus, it's poisonous, or at least skin-irritating. Depending on what type of epoxy you use, it may create poisonous fumes while curing (or significant amounts of heat). There exist "epoxy" types that are in fact not epoxy at all, they only look the like, and aren't necessarily easily identifiable by a layman. Not all epoxys even cure the same (there's sticky and non-sticky ones). You must get the mixture right, or it will not work well (cure more slowly, or inconsistenly, or not at all, or something different).

Wood glue, you can wipe off cleanly without leaving a trace using a piece of cloth, should a few drops fall to the floor. It's something you can wash out without much hassle (unless you let it dry) if it stains your clothes. It's something that will not provoke a skin reaction on your fingers or take half an hour to get clean fingers which are able to touch something without sticking to it, again. It is something that your three-year-old could, in the worst case, eat -- and most likely not a lot of terrible stuff would happen.

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For installing a dowel in the hole I'd prefer wood glue. However, given that the objective is not to plug an unwanted hole with a dowel but rather to repair a screw hole...

The hole could be filled with epoxy alone - no filler wood. The hole is drilled out oversize and then filled with just epoxy. An interesting outcome of the epoxy solution is that the hole is left with threads that fit the screw perfectly without any further compression or deformation of the surrounding wood.

The epoxy solution doesn't have to hold the screw permanently. If the screw is coated with some kind of mold release like wax before assembly then the epoxy will fill around the screw but won't bond to it. Alternatively, if the epoxy is bonded to the screw, the bond can be broken by heating the screw with a soldering or wood burning iron.

There are some descriptions at the West System web site.

A big advantage of the wood fill method is that the hardware and screw are installed later after the glue is dry. This avoids the clamping hassle that's inherent with the epoxy method.

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    For screwing into, you can buy "wood filler". AFAICT, this is two-part epoxy with plenty of sawdust mixed in to the resin (which makes it look acceptable, as well as creating strength as a composite material). – Toby Speight Oct 15 at 9:26
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    The trouble with epoxy as a stripped hile filler is that once set, it is a solid and pretty rigid material. You'll need to drill a pilot hole, and if it's not the right size the screw will split the epoxy and may exert so much pressure on the wood that the wood also splits. A "screwable" wood filler won't have this problem, it will include something such as sawdust to give it greater compressibility. – nigel222 Oct 15 at 10:14
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    Depending on the ultimate strength needed, it may be quite acceptable just to put three or four thin bits of softwood (like matchsticks) into the hole and then force them outwards with the screw down the middle. Friction may suffice, with no glue at all. – nigel222 Oct 15 at 10:18
  • @nigel222 When using epoxy alone (or with a filler blended in) the idea is that the screw is installed at the same time as the epoxy. It cures with the screw already in place so there's no need to drill a pilot nor cut threads after the cure. This would usually require clamping somehow to keep things in position until the epoxy has cured. – Greg Hill Oct 15 at 16:42
  • @Greg_Hill But then how would you ever get the screw out again without wrecking the item? OP's question was about door hinges. Doors swell or contract with dampness and do occasionally need to be taken off and planed. For a permanent joint you'd use a glued dowel, no screw. – nigel222 Oct 15 at 16:47
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You don't want to dowel the stripped screw hole: to plug it instead. The difference is that a plug is cross-grain while a dowel is long-grain.

The reasons?

Using a dowel...

  • Gives you end grain to screw into. Screws do not hold well in end grain.
  • Gives you a short- to long-grain glue joint. Such joints do not hold well regardless of the glue used.

Plugging

  • Long grain to long grain joint. Nearly as strong as the original wood.
  • Screw goes into long grain. Much stronger than a screw into end grain.

Procedure

  • Get a plug cutter of suitable size and cut a plug from the same kind of wood.
  • Drill out the stripped out screw hole using a bit the same size as the plug.
  • Dip the plug in wood glue (which see below).
  • Seat the plug and align its grain with the piece being repaired.
  • Tap the plug home — gently.
  • Let the glue dry.
  • Trim the plug flush using a sharp chisel or block plane.
  • Drill the new pilot hole using a bit of suitable size for the screw in question.

Done right, this sort of repair is virtually invisible, and, nearly as strong as the original wood.

Glue it in with a decent wood glue. Glue choice should be determined by usage: Epoxy is the glue of choice if the repair is likely to be wet. However, epoxy is also non-reversable, and takes a long time to cure. If it's ordinary furniture or cabinetry, I would suggest using either Titebond or liquid hide glue.

There's a simpler way, though. Don't plug it if you don't have too: just move up one screw size. If it's a #10 wood screw, move to a #12.

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If it,s a quick-n-dirty, wood glue.

Otherwise a competent epoxy, period, becuase you can dial it in to be exactly what you need.

I am not talking about random hardware store packs (not least, most are far too fast). I'm talking about a well-developed epoxy system such as West System. However, we could fan this out into a product like Git-Rot if wood deterioration warrants this. They will play well together; we overcoat West System, Git-Rot and Abatron all the time.

You are modifying the epoxy in two separate areas: Bonding filler, to allow you to reliably bridge irregular gaps between surfaces; and as general filler, if you need to fill inaccesible voids, or simply want to use the epoxy as the fill material instead of setting a dowel. As a filler, the epoxy can be "dialed down" to the same softness as the substrate, and that allows direct screwing the same way you would the substrate. The fillers also assure good characteristics from the epoxy.

You could also mix the epoxy to be harder and make it more like drilling into a hardwood bos, but for that matter, you could just glue in a threaded metal sleeve and have it act like metal.

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Neither is really needed. Use a slightly over-size dowel and hammer it in there. Sand off or cut the excess. It won't come out.

(edit) caveat: Obviously this answer is only applicable where the recipient wood is substantial enough to take a tight fitting dowel without splitting (example a door frame with stripped screws). If not, I recommend an exact fitting dowel (drill out to fit if needed) and a small amount of wood glue.

  • Hello, and welcome to Home Improvement. Thanks for the answer; keep 'em coming, but one question; does this depend on the strength of the surrounding wood? (Don't want to split the thing...). And, you should probably take our tour so you'll know how best to contribute here. – Daniel Griscom Oct 16 at 19:01
  • @DanielGriscom yes, but so does gluing it. I just drill out the hole to exactly match the dowel -1mm then hit it, example from my current work list, a hinge thats been pulled out of a door that was opened too wide. Drill out the screw holes to 7mm, hammer in an 8mm dowel. Refit hinge. – bigbadmouse Oct 17 at 7:15
  • I was wondering if the stress (and there needs to be a significant amount if you hope the pin to stay without glue) might itself split the wood. A glued peg of the right size shouldn't add stress. (Just looking to help you improve your answer.) – Daniel Griscom Oct 17 at 11:29
  • no, because I drill it out to slightly less than the size of the dowel.There's no harm in adding a dab of wood glue, but no need ether, and it gets messy when the two parts are a tight fit. – bigbadmouse Oct 17 at 12:51
  • Sorry; you're misunderstanding me. If you have the dowel large enough relative to the hole so that the friction alone keeps it in place, then it has to have force against the walls of the hole, which (on thin pieces) may split the piece. If you're using glue, then the dowel won't need to have any force on the walls of the hole, thus no force that might split. I think this info might be helpful to add to your answer. – Daniel Griscom Oct 17 at 13:20

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