# Wood Glue or Epoxy



## medsker (Jun 1, 2011)

I am needing some advice. I am repairing a wooden chair that has came loose at the joints. Some joints are tenons others are simply dowels. What is the best thing to use. Epoxy or wood glue? Thank you.


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## Dal300 (Aug 4, 2011)

Clean out the old glue first. 
Modern wood glue is stronger than the wood. I try not to use epoxy for anything that I want to be nice clean and pretty. That is because I always make too big a mess.


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## donbee (Feb 7, 2009)

Never use epoxy on a chair unless it is a last ditch repair.
The reason?
It can never be repaired again.
When I repair chairs (I've done many) I pull them apart, clean out all old glue repair or replace undersized or broken parts and refit with good clamp pressure. I use Titebond III for most of them.

db


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## NatalieM (Jan 6, 2013)

Ha, speaking of Epoxy being messy. I was using it yesterday for the first time in a LONG time to fill some gaps and cracks in a piece of wood and forgot to use gloves. OMG. Talk about a mess! I used a gel type and I got it ALL OVER my right hand. I wasn't too concerned, because I just was going to wipe it off and use some solvent for the rest, but guess what? When it says it dries in 5 minutes that means that one second it is goopy and the next second your fingers are glued together like superglue!

I took me about 30 minutes and a lot of toxic Acetone to get it off. Lesson Learned!

As far as the furniture goes, like Dallas said you have to clean off the old glue. Traditional wood glue will not adhere to old glue. Getting it all out of those holes can be almost impossible, which might be a good reason to use Epoxy which will adhered if there is some old glue residue. You still have to clean as much of the old glue out as possible.


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## shipwright (Sep 27, 2010)

Important question: How old is the chair?
If it is old enough (pre 1950's) it is likely hide glue.
In that case you are lucky because you don't have to remove the old glue. The new will melt and bond to the old and your chair will be repairable again in the future if necessary. Many custom woodworkers still use hide glue for chairs because it can be reversed. 
I am a big fan of epoxy and have used gallons and gallons of it but don't use it on your chair, +1Don.


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## NatalieM (Jan 6, 2013)

Hey Paul, I would love to know the best Epoxy for using with wood, and a source other than home depot. I don't use it much but will be doing some gap filling and need some recommendations.


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## kati (Feb 8, 2014)

is there a certain epoxy to use or can i use all?


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## MalcolmLaurel (Dec 15, 2013)

For gluing wood to wood epoxy is not the best choice… it hardens too fast, doesn't soak into the wood, and is a weaker bond than wood glues that soak into the wood as they slowly dry. Save epoxy for when you're gluing plastic or metals.

The slower drying epoxies (you can get 15 or even 45 minute epoxy but it can be hard to find, R/C hobby shops sometimes carry them) tend to be stronger. On the downside they may run more before they set.


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## medsker (Jun 1, 2011)

Thanks for the information everybody. I'm going to go repair the chair…with wood glue!


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## shipwright (Sep 27, 2010)

No offence Malcolm but I certainly hope you are misinformed. If not I have built several boats, including my own, that will fall apart soon.
Hobby store epoxies (read fast cure stuff) bear little resemblance to the real thing. " Real" epoxies take from around 12 to 24 hours to achieve full cure and are about the best permanent wood glue there is. My choice for boat building were always those from Industrial Formulators of Canada. They were bought out by System Three and that company still sells most of the old IFC line under their original names. My favourites were Cold Cure for general gluing and structural fillets and S1 Sealer for sealing anything.
Look for System three online or at plastics dealers. West System is OK too but not my preference. There are lots of others.
As far as this relates to the OP's question, ... Epoxy (real thing) is too good a glue. It will never come apart if you need future repair.
I have a blog that answers a lot of epoxy questions here.


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## MalcolmLaurel (Dec 15, 2013)

OK Paul, yes, you're right. I was referring to generic hardware or hobby store epoxies. The longer curing ones you're referring to have time to soak into the wood fibers to get a good bond, but are harder to find locally.


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## Texcaster (Oct 26, 2013)

A lot depends on how valuable the chair is and how sloppy the joint is. I use a Bote-Cote product called
Epox-E-Glue. It is pre-thickened with cabosil, it won't drip, it is gap filling and is strong across the gap. 24 hr. set.

I use it as a bog, colored with wood dust. Also in hard to clamp situations ex: I put an Ebony cap on the ends of my double bass fingerboards. The fb is put in a vise vertically and the cap pushed into place and left to set. If not colored it dries grey.


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## DrDirt (Feb 26, 2008)

REgardless of glue choice if you are using PVA wood glue or epoxy - you need to get the surfaces clean again.

If it is hide glue, like shipwright mentions - hide glue can bond to itself and is reversible.

If you can open it up, I would pop the joints, then use hide glue again - if you don't want to mess with a glue pot, use Titebond Liquid hide.

If it is a modern piece of furniture, I would go with a slow epoxy, because you are likely to need some of the gapfilling properties to get it tight again - as the joints are already loose.


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## Texcaster (Oct 26, 2013)

Liquid hide glue should not be confused with proper hide glue. I wouldn't use it on anything important.


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## Picklehead (Feb 12, 2013)

Not intending to hijack this thread, trying to introduce another option that I, unfortunately, have no experience with.

Has anybody used either of these?



















I was wondering, myself, if I should use these the next time I have a loose rung. Maybe info that would be pertinent in this case.


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## runswithscissors (Nov 8, 2012)

I always make it a point to wear vinyl or latex gloves when using epoxy, but it's almost impossible to avoid getting it on you. One reason for avoiding contact is that people can build up sensitivity to it. Once that has happened, it's just like any other allergy-something you dare not expose yourself to again.

When I do have to clean it up, I always use vinegar instead of acetone. Works as well, if not better. You need to rub it around and rinse frequently with more vinegar. Unlike acetone, it's not volatile and is non-toxic.


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## DrDirt (Feb 26, 2008)

Texcaster - the liquid hide still is reversible, just has additives, which prevent getting that initial tack in a rub joint.

However curious why you would find in unsuitable for gluing dowels into a chair. I use hot hide myself, but have used liquid in the past with no issues, certainly hot hide is the ONLY way to glue stringed instruments up.

But for those that don't want to mess with urea to get a decent open time for gluing chairs - liquid hide is still stronger than the wood itself, and fully reversible.


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## Texcaster (Oct 26, 2013)

Dr. Dirt, mine is a luthier perspective. Hot hide glue can also be cooked in hot water in small plastic bottles to ease application.

http://www.mandolincafe.com/forum/showthread.php?52321-Titebond-Hide-glue attn. post #15


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## LeeBarker (Aug 6, 2010)

I, too have done lots of chairs.

One method not mentioned: Ream out the hole (mortise) in question and hand fit a cut plug or dowel and glue it in (with any glue!) and then bore it out to proper size.

Polyurethane glue has not been mentioned. A loose but otherwise sound joint can be successfully repaired with polyurethane glue by making a mechanical joint possible (notches, cross-boring) and letting the glue do its thing. Mask the joint carefully and time your cleanup.

Picklehead: I read in a review that the "swells wood" products work at first but fail over time. I wish I could quote my source.

Kindly,

Lee


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## donbee (Feb 7, 2009)

Plugging and reboring is a perfectly acceptable method.
One thing I always hate to see when i get a chair to repair is nails or screws put in across a mortise joint. In almost every case some damage is necessary in order to disassemble the joint and repair it.

db


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## DrDirt (Feb 26, 2008)

Thanks Texcaster - I I had always viewed a hot hide only for instruments, because of the bond - where the hide glue is nearly a rigid glass, that allows the instrument to have better resonance - behaving more like a continuous single piece. (since my daughter got me to cough up 2 grand for a starter violin for the youth symphony) On the site you mentioned #21 - they referenced a Stanford study on hide vs Liquid glue - which matches my experience with it when I made a Morris Rocking chair ~10 years ago now.

I add urea to the hide glue, because otherwise for furniture the tack is just Too fast to get the joints all put together as subassemblies before it jells and tacks, but maybe I am working too slow, but still I need the open time. 

http://www.wag-aic.org/1990/WAG_90_buck.pdf

*Conclusion*
The results of this testing reinforce the importance of maintaining a controlled environment for the
display and storage of wood objects. The most critical factor in the strength and stability of the 20 liquid
hide glue and 20 hot hide glue joins was the environment.

*Based purely on strength characteristics this testing indicates that liquid hide glue is the glue of choice for repairing a join which will undergo significant stress, such as the structural join of a chair in regular use. * But, more importantly, that decision must also take into consideration the environmental conditions.
Under normal conditions of 50% RH and room temperature liquid hide glue provides the strongest
bond. However, hot hide glue proved to be the more stable of the two glues under extreme conditions
of high heat or high humidity, and thus would be the more desirable choice if fluctuating environmental
conditions are anticipated.

It is also important to consider whether a very strong bond is desirable, especially if it is coupled with
a higher percentage of possible glue failure. In instances where the glued area will not be subjected
to excessive stress, the slightly lower strength, lower percentage wood failure hot hide glue is more
appropriate.


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