Glueing Teak

[Larry L Edinger]

What is a good glue for glueing teak ? The Teak is off a old sail boat that wasn't kept up. The old glue joints let go, and the Teak seems to be dry ( On oil in it).
Thanks :confused:

[James Tibbetts]

Only thing I have ever seen used was West Systems epoxy. The mating surfaces were always wiped down with lacquer thinner just before glue up. Just for insurance sake I would still use an epoxy on it, dry or not.

[Mel Fulks]

Lacquer thinner is probably better than not cleaning with anything ,but I've been told LT actually has oil in it. I would use acetone or MEK to wipe the wood. Epoxy is good but I think gorrila ,type two or type three would also work . Don't know which is "best".

[Mel Fulks]

P.S. If it's going back on boat ,as opposed to being repurposed, definately epoxy.

[Larry L Edinger]

It's is going back on the boat.
I told the guy that he needs to keep the Teak oiled. Right?

[Mel Fulks]

Larry, just noticed no one has posted about the oil question. Marine finishes are a special niche, check with a boat place.

[Sam Murdoch]

Epoxy is the best choice. The value of wiping teak down is a topic of controversy. I typically just sand to make certain that it is clean and that I am gluing to a fresh surface or glue up after machining. Teak can be varnished or oiled or left bare. Teak decks last a long time and are typically not finished - often cleaned with a good scrubbing using sea water. It all depends on the look you wish to achieve and the amount of work you want to invest. The silvery gray of weathered teak can be very nice but so can a grain filled well varnished teak look really beautiful.

[Mel Fulks]

Sam,I hadn't heard the controversy thing before. I worked for a highly skilled German pattern maker for one year a long time ago. He was making a hatch for his sail boat out of teak and had to glue it up . It fell apart right after he removed it from the clamps. I told him I had read that wiping it with acetone or MEK helped ,he used MEK and the joint held. To me this this inadvertant experiment is useful here because the MEK was the only variable. P.S : I am not a pattern maker and learned that in just one year!

[John Coloccia]

The thought is that cleaning does little but smear around the oil. I tend to be in that camp, at least as far as rosewoods are concerned, and I just glue freshly planed surfaces. That said, I always recommend following the manufacturers directions, and West has specific instructions for Teak:

http://www.westsystem.com/ss/surface-preparation/

And West is pretty much all I would use to glue teak.

[Mel Fulks]

Well, solvents do vary in strength and MEK is the strongest widely available . I just don't understand how it could possibly be a negative. I've noticed over the years that the go to technical guys at the glue companies stress that any gluing of any kind of wood should be done as soon as possible after surface dressing as oxidation of oils ,pitch ,etc have a strong negative effect on joint strength. They point out the glue actually penetrates into the wood very little with any species.

[Sam Murdoch]

Sam,I hadn't heard the controversy thing before. I worked for a highly skilled German pattern maker for one year a long time ago. He was making a hatch for his sail boat out of teak and had to glue it up . It fell apart right after he removed it from the clamps. I told him I had read that wiping it with acetone or MEK helped ,he used MEK and the joint held. To me this this inadvertant experiment is useful here because the MEK was the only variable. P.S : I am not a pattern maker and learned that in just one year!


One theory is that using a solvent may contaminate the epoxy as you glue the joint. I can find quite a few references that argue for each technique.
Having said that I agree that it is best to follow the adhesive manufacture's directions - why do any less? I have used acetone as a prewipe to an epoxy/teak connection, also I have just milled the teak, spread the epoxy and clamped the assembly together. I think that milling and soon thereafter doing the glue up is an important factor. Both techniques have worked well - no failures ever. Lots of variables may have supported that success rate and so I go back to suggesting that it is best to follow the manufacturer's recommendation for their specific epoxy.

[Mel Fulks]

Sam, I don't see any theory involved in this and don't agree with the mfg. advice posted earlier . Lacquer thinner should not be used ,as I posted earlier it has wax and oil in it. When a member here reccommends lacquer thinner it is an honest attempt to help . When a glue mfg reccommends it ....it is a glaring mistake. Acetone and MEK are appropriate and evaporate quickly and should be allowed to do so. Some woods have oil or wax in them that can impede a good glue bond,and since there is a way to greatly mitigate that risk I think it wise to do so.

[John Coloccia]

Sam, I don't see any theory involved in this and don't agree with the mfg. advice posted earlier . Lacquer thinner should not be used ,as I posted earlier it has wax and oil in it. When a member here reccommends lacquer thinner it is an honest attempt to help . When a glue mfg reccommends it ....it is a glaring mistake. Acetone and MEK are appropriate and evaporate quickly and should be allowed to do so. Some woods have oil or wax in them that can impede a good glue bond,and since there is a way to greatly mitigate that risk I think it wise to do so.

What's the problem with lacquer thinner? It's mostly Acetone, MEK, Toulene, etc...powerful solvents. West has been doing this for many decades, and they're the most well respected name in marine adhesives. I think they know what they're talking about.

[Sam Murdoch]

… in this case West recommends acetone as the prewipe. See John's link in post # 9 above.

[Mel Fulks]

I just went and read that again. It says "lacquer thinner, acetone, or other appropriate solvent". They reccommend one inappropriate solvent and don't mention MEK. I find that sloppy. No wonder there is debate and theory!

[Mel Fulks]

John,I just now saw your question. Lacquer thinner is MOSTLY solvent but has waxes or oils to retard too quick drying .There may be different proprietary formulas but those additives are what makes it "lacquer thinner" and might explain the pushing oil around thing .

[Sam Murdoch]

I just went and read that again. It says "lacquer thinner, acetone, or other appropriate solvent". They reccommend one inappropriate solvent and don't mention MEK. I find that sloppy. No wonder there is debate and theory!


Mel, I'm not trying to argue with you - just trying to be clear for the OP - below is the quote from the West System thread detailing specifically how to prepare teak and other oily woods - found down the page from the general comments you quote -

"Teak/oily woods-Wipe with acetone 15 minutes before coating. Solvent removes the oil at the surface and allows epoxy to penetrate. Be sure solvent has evaporated before coating."

[Mel Fulks]

Sam, I appreciate your posts and sure all intentions are good . When I find a mistake in something like that ,I stop readin
And I think most would stop there ,it never occurs to me that the writer might change his mind in another paragraph. As you stated what I wrote was their words. The use of LT is wrong and the recommendation to do so is sloppy.

[John Coloccia]

John,I just now saw your question. Lacquer thinner is MOSTLY solvent but has waxes or oils to retard too quick drying .There may be different proprietary formulas but those additives are what makes it "lacquer thinner" and might explain the pushing oil around thing .

I think lacquer thinner generally contains naphtha and possibly mineral spirits in it. You can get low quality naphtha and spirits that leave behind oily residues, but high quality of the kind you would use in thinner evaporates completely and leaves no residue at all. In fact, mineral spirits are generally considered to be de-greasers and are used industrially to remove oily residues from items. Iit's one of the traditional pre-paint cleaners that you would find in an auto body shop. Hardware store mineral spirits generally won't work well because they're not pure enough, but spirits designed for the task will remove all of the oils and leave nothing behind. Similarly, the VM&P in VM&P Naphtha generally indicates it's appropriateness for use in finishes and lack of oily residue....which would be disastrous in a finish.

I do believe that you're correct about their being used as retarders. I can't imagine how quickly pure acetone, toulene and MEK would dry in a spray mist....you'd probably just have dry finish hitting the target! :)

[Mel Fulks]

I had no idea what was in LT until I did some googling to be sure. This subject first came to my attention by an employer who had some background in chemistry. I was using LT myself at the time I was corrected and told to use MEK. The very type of work you do assures your knowledge and skill. The mistake belongs to someone at the glue plant ,or advertising agency. If I were a steady user of their product I would give them an angry call.

[John Coloccia]

I had no idea what was in LT until I did some googling to be sure. This subject first came to my attention by an employer who had some background in chemistry. I was using LT myself at the time I was corrected and told to use MEK. The very type of work you do assures your knowledge and skill. The mistake belongs to someone at the glue plant ,or advertising agency. If I were a steady user of their product I would give them an angry call.

It's easy to confoozle what goes into these concoctions. I just went out and looked up the MSDS on my thinner. Turns out it's a large part naphtha and spirits...larger than I thought.

[Mac McQuinn]

Found this;
http://www.jamestowndistributors.com/userportal/show_product.do?pid=1265&familyName=Smiths+Tropical+Hardwood+Epoxy
Mac

[Jack Battersby]

In the "for what it is worth" Category, i'll throw in a couple of cents.

I have been using epoxy for 30 years for gluing wood. I have used MAS, RAKA, West System, and System 3 throughout those years as their formulas changed, we have changed what we used to best suit our needs. For a glue up, any of them will work fine, though some of these manufacturers still sell epoxy which blushes and you should avoid that if there is any laminating involved. (long discussion not really pertinent here). In general, you want to use the epoxy formula with the best viscosity or flow rate. I have found RAKA and MAS to flow the best.

The only thing which hasn't changed is what we use for cleaning joints when necessary. As a general rule, when possible, you should always sand away contaminates to get to bare wood. I prefer Denatured Alcohol as a cleaner for epoxy, but will not penetrate deeply and open the pores of the wood. Acetone is just as effective as denatured alcohol for the most part. Just think about how dry your skin gets when denatured alcohol is in regular contact.

In order for epoxy to be effective, the wood needs to be contaminant free and relatively dry. Air dried is fine, however oily wood which releases to the surface is problematic.

If you are going to use epoxy then in my experience, there are a few things you need to know. First as this thread implies, the surface and just beneath the surface needs to be clean and dry. Taking a heat gun to the joint for a minute or so before you glue up will help in a couple of ways. First, it will dry oils near the surface, and second it will assist the epoxy to penetrate the joint. Never thin epoxy with thinner when making a structural joint. It can be thinned and used as a penetrating coat, however the thinner will significantly lessen its holding abilities.

When you glue with epoxy, you always want to spread clear epoxy on the joints and let them set for a couple of minutes before they mate. The clear epoxy will penetrate the surface without starving out any fillers. Then mix some clean wood flour in with the remainder of the mix and spread that on the surfaces as well. Wood flour is more structural than say microballoons or talc though it does take a bit more effort to sand it up.

When joining the two surfaces, never over clamp. This is the biggest rookie mistake and in general the source of most failed epoxy joints. Epoxy is not like carpenters glue where you need to squeeze the heck out of the joint. You absolutely do not want to squeeze the excess out of the joint with epoxy. Just a firm clamping will do the trick. In most cases, we use spring clamps when using epoxy as a glue. If you are screwing it down, then do not overtighten when doing so.

After you have glued up your joint, be sure an clean it up as much as possible. NOT with chemicals, just by scraping off the excess with a putty knife or the like. Epoxy dries very hard and when sanding, the surrounding wood gives way much quicker than the epoxy will.

Now remember that epoxy takes days to cure. It may be dry in 24 hours but is not fully cured for a few days depending on your climate. You should never sand green epoxy unless absolutely necessary and if you do, make sure you have a mask on, good ventilation and you are using a vacuum assisted sander.

Lastly (AND THIS IS IMPORTANT), remember that epoxy must be protected from UV. Epoxy left unprotected in direct sunlight over a long period of time will break down. There are some epoxies which have a certain amount of UV tolerance, RAKA comes to mind, however even those are UV resistant, not UV protected.

Remember that there are alternatives such as 3M 5200 which is very popular in decking out topsides of boats, but it won't make a clean invisible glue joint if that is what you are after.

Hope that helps a little.

[Jack Battersby]

OK, so one more thing. I have an online video which shows using epoxy as a glue for a set of scarfed gunwales, but I didn't want to post it because I didn't want to appear to be pushing you to another site, however I read the forum rules and I think we are OK with this and if not let me appologize right off the bat to the good people here at Sawmill Creek.

Anyway, if you go to http://sandypointboatworks.com/wood-boat-school/video-library and look about half way down the page, you will see a video entitled "using epoxy as a glue". I think it may clear up pretty much everything I wrote above. There is also another video there called "Installing Seat Risers" which show you how to attach items to a hull using epoxy which may help as well.

Happy to answer any questions if I can.