by Eric Meier
Conventional wood glues like Titebond are water-based, and they rely on penetrating into the grain of the wood, and then (once the water has evaporated) hardening, leaving a bond that is in many instances stronger than the wood itself.
The Problem:
Many tropical hardwoods are so oily or resinous that they’re practically waterproof. It would then stand to reason that if conventional wood glues need to penetrate into the wood in order to obtain a strong bond, then these oily woods would present a challenge in gluing.
Above you can see a picture of untreated, raw Cocobolo, which was misted with a spray bottle full of regular water. It should be plain to see that this wood, (along with a handful of other tropical species), appear to be nearly waterproof.
They’re technically not waterproof: since all wood, (even the Cocobolo pictured above), contains some degree of moisture that changes depending upon the relative humidity of the surrounding air. But for most intents and purposes, in the short amount of time that is elapsed in the gluing process, so little of the glue sinks down into the wood grain that it is essentially waterproof, or perhaps more accurately, glueproof.
Between different types of wood, and even within the same species of wood, there can be a lot of variability in oil/resin content, and gluing success/difficulty. Sometimes an oily wood can be glued with regular yellow glue with no problems, and in the next instance, the glue joint will almost fall apart on its own.
It would be preferable if the objects which we are building would stay in one piece!
So what can be done about this unpredictable nature of wood?
Some Solutions:
Please note that these are some solutions that can help give consistent results in gluing troublesome woods; but it is by no means a cure-all that is guaranteed to work every time, with all wood species and with all types of wood joints. On the whole, employing these tips should result in generally stronger, longer-lasting glue joints in oily woods..
1.) Wipe the wood surface with a solvent prior to gluing.
Since the primary problem that tropical woods present in gluing is their oiliness, (with density probably being the second biggest problem), any of these natural oils and resins that you can remove from the wood surface will help the glue adhere that much better.
While it’s not a cure-all, wiping the wood with a solvent first goes a long way. But you have to be sure of two things: first, you should try to glue the pieces of wood to be joined as soon as possible after the solvent has evaporated from the wood surface. This is because the wood’s oils will tend to migrate back to the surface of the wood where you removed some of the oils. Secondly, you have to be sure that the solvent you’re using is actually dissolving and removing the wood’s oils. A good way to gauge this is by checking the towel that you’re using to wipe the solvent to see if it’s changed to the wood’s color.
Note in the example above, mineral spirits was used to lift some of Cocobolo’s oils off the wood surface: and you can clearly see the stained orange cloth as evidence. If you’re initially testing a solvent, make sure that the wood is clear of any small particles of sawdust that might make it appear as though the towel is being discolored. Try a cloth with water first as a baseline: it should basically stay white since the water does not dissolve the wood’s heartwood extractives. Some common solvents that you can try are: acetone, denatured alcohol, lacquer thinner, mineral spirits, and naphtha.
2.) Sand the wood to help open up the grain.
3.) Use synthetic, non-water-based glues.
Since water is repelled by the wood’s oils, using water-based glues like Titebond® can pose problems—though Titebond® II or III are usually better at gluing oily woods than Titebond® Original. Instead, use glues that aren’t water based, and/or glues that can bond a wider variety of materials like plastics and other non-porous surfaces (since that’s practically what we’re doing with these exotic woods anyways).
A List of Troublesome Woods:
Wood | Gluing Notes |
Bubinga | High density, closed pores, and natural oils can cause problems with glue penetration. |
Bulletwood | High density and moderately oily. |
Cocobolo | Very high oil content and high density. |
Cumaru | High oil content and high density. |
East Indian Rosewood | High oil content and medium/high density. |
Ebonies | Some oil present, along with very high densities. |
Ekki | High density and moderately oily. |
Goncalo Alves | High density and natural oils prevent water absorption. |
Greenheart | High density and natural oils. |
Honduran Rosewood | High oil content and high density. |
Ipe | Reportedly very difficult to glue in exterior applications, especially for the long term. |
Jucaro | High density and oil content. |
Katalox | Very high density, along with natural oils. |
Kingwood | Very high oil content and high density. |
Lignum Vitae | Extremely high oil content and density can pose gluing challenges. |
Olive, East African | High oil content and high density. |
Osage Orange | Oils present can give gluing problems. |
Purpleheart | High oil content and high density. |
Rosewoods | Typically very oily and very dense. |
Santos Mahogany | High density and moderately oily. |
Teak | Oils/resins can present challenges in outdoor applications. |
Verawood | Extremely high oil content and density can pose gluing challenges. |
See also:
Are you an aspiring wood nerd?
The poster, Worldwide Woods, Ranked by Hardness, should be required reading for anyone enrolled in the school of wood nerdery. I have amassed over 500 wood species on a single poster, arranged into eight major geographic regions, with each wood sorted and ranked according to its Janka hardness. Each wood has been meticulously documented and photographed, listed with its Janka hardness value (in lbf) and geographic and global hardness rankings. Consider this: the venerable Red Oak (Quercus rubra) sits at only #33 in North America and #278 worldwide for hardness! Aspiring wood nerds be advised: your syllabus may be calling for Worldwide Woods as part of your next assignment!
I would second the use of G/flex (made by West System) for oily woods. West System specifically recommend G/flex for this purpose. I have used it very successfully for bonding teak. To prepare, I sand with 60 or 80 grit sandpaper (needs to be new so the grit is ‘sharp’). Then either blasting the dust with a compressor or vacuuming to get all the dust out of the pores. I then wipe with acetone before gluing (need to apply the glue within a few minutes of the acetone evaporating and certainly no more than 30 minutes later). Gently warming the… Read more »
Hi Everyone, I’m planning on using Goncalo Alves on the back of an Alder guitar , whats the process please and what glue would be proper . Thanks NM
This is very good information. I have a walnut rifle stock that has a large crack, actually a break, running lengthwise more or less with the grain underneath the fore-end area. This was a “bring back” from a relative in WWII and I would like to repair it. The problem is, it’s an old military stock that has had a lot of oil or grease soaked into it. I plan on separating the crack a bit and cleaning it out as best I can with acetone but of course I won’t be able to get every bit of the oil… Read more »
This article directly addresses problems I have been having recently with Bolivian Rosewood (I was using as a trim for a shelf). Couldn’t glue it (Titebond), polyurethane sat on the surface as a pasty substance, and it was just being ornery. Now, I feel a bit stupid as I am a chemist in the daytime, have worked with polyurethanes in the past, and worked for a North American forestry company for 30 years! Should have anticipated that surface oils could cause issues. (Thought it might be related to surface metal content like calcium, which treating with trisodium citrate would ‘cure”.)… Read more »
i am using Bolivian rosewood for the same project as yours. What was your final resolution and outcome?
Wow…now my memory needs to work!! Re: the polyurethane, I was able to use de-waxed shellac as a primer. The polyurethane worked well with that on the surface. Just make sure it is de-waxed! Re: the gluing, I just sanded more heavily after my first try and wiped down the surface with acetone to help “de-oil” it. Hope that helps with your project!
Here is an odd question for someone. What is the most affordable hard, dense, oily wood? I am thinking of making some sliding dovetail drawer slides out of wood so a very hard oily wood sounds like a good choice for that.
It depends on where you live. I am in Australia, and I always use Spotted Gum for drawer runners because it is available economically as decking boards. If you live in America, you could try Ipe as it is commonly sold as decking timber.
maybe look at decking lumber companies. I got a local one near me and stuff like cumaru, massaranduba, tigerwood were much cheaper than ipe or teak.
I made a desk and used ipe for the hanging file slides. It worked great and has held up very well for the past 10 years!
One thing I’d ad is that right after you sand it use a compressor and blow out the pores to give yourself more gluing surface area. Each of those pores will create more area and since they tend to angle it also gives a small amount if directional glue space.
Nice article. Thank you for this. I have a partially broken Stanley plane handle in oily rosewood that I want to repair. This is exactly the information I needed. Gorilla glue sounds like my solution.
i’m trying to resurrect a weathered teak patio set. apart from the surface issues, one of the supports has split, on the diagonal. luckily, it isn’t particularly visible until the table is folded up. the information on stripping oils is great, as is the recommendation for glues. (i would have done it all wrong, and the joint wouldn’t have held.) i’d like to glue and clamp it, but i don’t like to trust the glue as a permanent fix. would it be better to hold it together with a (brass) screw, or to use a dowel? (bow ties look pretty… Read more »
Hi, Maybe late to give some kind of an answer, but I’ll do it anyway. I repaired 2 teak outdoor chairs. (To put it into context, I never take them inside or so during winter, they just are always outside during summer/winter). We have old teak chairs (20yo+), they never broke/cracked. About 10years ago I bought 4 extra chairs. These (2 of them) did break. Why I tell you this is? It might be a structural building problem/quality of the wood (just saying :-) ) Now, I live in Belgium, so the glue I use mostly, is PU glue of… Read more »
Biscuits could be an option.
Can anyone recommend glue for Ipe?
What is the best glue to use to laminate pantagonia rosewood (curupay) to make a dining table?
If I was using that wood, I’d test a few different glues on scrap wood first instead of relying on what someone said.
I glued Patagonia Rosewood with T-88, and the joint came apart at the resin seams under high stress (coffee and play table). I removed all the resin mechanically, cleaned surfaces with mineral spirits, and reapplied T-88. Joint stable under sometimes high stress for about a year now.
If you wish to do a glue up with any oily woods, Try this. I had a piece red wood of a sort, which was waxy and oily. the piece was 1”X 1″ X 12 Inches. I put it in a microwave in steps of 10 seconds to a full minute in total. The waxes and oils came running out. I used a paper towel and just wiped it off. The wood ended up Hot and dry and free of oils. It will take quite a while for the wood too cool, so be careful handling it. After sanding, I… Read more »
What glue would you recommend for teak? Specifically a part of a teak umbrella frame one of the arms snapped as I was raising it.
Thank you for this wonderfully, delightful website. You have opened my eyes to a ‘New World’ of woodworking with exotic wood I was not aware of being available in the UK.
I am going to use 200 year old African mahogany to make a table; will this still need special treatment when gluing? I shall also use some of this to make a frame for your poster when it arrives.
Thank you for taking the time to read this and I look forward to your comments.
You shouldn’t have any issues gluing mahogany. Thanks Peter!
I remember making a pen from lignin vitae and having to glue the metal parts together around the wood because nothing would stick to the wood! Nice final product though. LV requires no finish and just fine sanding.
Can Hide glue be used to glue Santos rosewood veneer to birch plywood substrate after wiping with acetone?
yep and titebond will do the trick
Has anyone tried to glue purple heart? I have just made a (hand-cut) dovetailed jewellery box out of it with incredible difficulty and then glued up but some of the joints really struggled to come up.
I accept the points regarding the use of acetone but if anyone has had a successful experience can you please share your knowledge!
thanks,
matthew UK
I glued rosewood to cypress. Read a while back, when gluing oily woods, the best way is to glue the wood right after cutting your piece. The heat from cutting will move the oil away from the edge. ASAP
apply glue and join the other piece. It has been 7 years and the plate is beautifully together. Hope you have success, try a small piece first.
I build interior cabinetry and the teak grating and dive platforms for 70′ yachts. One of my jobs from years ago, called in a warranty report for the teak dive platform. I laminate solid teak, 3 layer to be almost 2″ thick. I use 3M epoxy, cure it in a vacuum table, rough cut it on a CNC, and finish it with a trim router. The teak strips were cleaned with acetone before assembling. Some of the epoxy has started to separate. These yachts see the the blue water and lots of UV. Does anyone have any experience tring to… Read more »
Resorcinol glue. Once you’ve used it, you’ll never go back. Still available, just from obscure companies. 4 hour pot life. Sets in 10 hours, although let it stand for a couple of days before going crazy with more shaping. Light sand planed edges, degrease with acetone or lacquer thinners, apply to both sides of the joint with a stiff brush, working it into the wood, no holidays, not even a bubble (you will understand this better after you’ve done it once) clamp that baby up, and it is now one piece of wood. If it won’t adhere to the surface,… Read more »
Whatever you’re about to do to remove the oils, here is a starting point: iron the surface as if it were a garment. That’s right – use an ordinary clothes iron with an old T-shirt or whatever between the iron and the wood surface. I discovered by accident that this really draws the oils to the surface and you can just wipe them away with the T-shirt. As others have mentioned, the oils will migrate to the surface again, but doing this a few times surely must reduce the overall levels of oils near the surface. Warning: I only found… Read more »
We have a carved cane made in jamica several years ago. It’s made of ironwood. It is broken in half with a clean cut to glue back together. The cane means a lot to us & my husband needs it. Please let me know what glue I need & the process to put it back together. Thank you.
Is the split diagonal across the grain line, or what direction and place is the break at?
I would think the break will be vertical. I us 2 walking sticks to get around and they are both vertical grained.
Can anyone recommend a glue that will work on Milo wood joints?
Have you (pl.) ever noticed that when you use masking tape (etc.) on a smoothed but unfinished tropical hardwood (like cocobolo or Braz. r’w’d), when you remove it, it leaves the area to which it was applied, paler and slightly depleted of color (some of which comes off on the tape)? Well, I’ve found it helps in gluing, because, I think, it draws out waterproof resins. I prepare the surfaces to be glued and cover them with masking tape (lately, I’ve had good results with transparent packing tape, warming it, just slightly, with a heat gun, and pressing it down… Read more »
In his book, “Classic Guitar Making” (Copyright 1974, published by Lawrence A. Brock), Arthur E. Overholtzer writes about removing pitch and tar from Brazilian Rosewood. After sawing to size. He used “Spic and Span” laundry detergent and water, completely immersing the boards. He agitated through the day and changed the detergent solution daily, for a week, then boiled in clean water, with 3 changes. He taped the ends of the boards to slow evaporation from the end grain, and let them dry for a week. Titebond water-based glue worked fine on rosewood treated this way. One of his students, Rose-Ellen… Read more »
Has anybody ever had problems gluing yellowheart wood? Does it have a high oil content like purple heart or cocobolo?
I have recently glued yellow heart and purple heart for a segmented turned bowl. I had no problems and I used Titebond original.
I am somewhat new to woodworking, as I was a tool & die maker for 41 years. I know that the super glues have a tendency to break down in about 5 to 7 years, but I am wondering about the type that uses an Ultraviolet light to activate it. I have had great success using it to repair ceramics, some wood, and plastic. I have even glued Teflon on cast iron. Since Teflon is so slick, it really presents an economic issue to bond it to anything. I also have used it to bond an old wood plane base… Read more »
Not having actually seen knitting needles, it’s hard to visualize what is being done. In the end, it will come down to how clean the fit is between the two mating parts. If it’s a clean fit, I would just use CA glue (aka “super” glue). If the fit is sloppy or loose, your chances of long term success are much lower, but you could try a two-part epoxy to take advantage of it’s gap-filling properties.
I haven’t used the G/Flex yet that was recommended by Wood Sculptor, but I have used Smiths Oak and teak Epoxy, which worked fine and without any use of solvents too. It also remained flexible and had a discrete glue line.
He is utterly on the pin with Cyanoacrylate, it wasn’t designed for this, and will fail normally sooner rather than later. Temporary repairs ONLY, brittle, and degrades under all sorts of conditions.
For all these oily woods use either G-2 (System Three Epoxy) or G/Flex (West System Epoxy). These adhesives are specifically made for these woods. I prefer the “repair viscosity” G/Flex as it helps hold the joints together where clamping is difficult. Never use cyanoacrylate adhesives (CA or superglues) except as a temporary bond – they always fail after a few years. The G-2 and G/Flex adhesives remain flexible whereas CA becomes brittle so as the different woods move differently over time/temperature/humidity only the flexible adhesives can hold the oily woods together. Titebond Original works sometimes but the Titebond II and… Read more »
Many thanks. I’ll give it a try.
I use the nonflammable formulation of Zip-Strip. It’s readily available in hardware stores where I live, and I think it’s widely distributed.
I brush it on with a throwaway acid brush, give it a few minutes, scrape it off with a razor and clean up with water. If I’m in a hurry I’ll even use a blow drier to dry things off before gluing.
Cheers!
Hello, Carter, thanks for the suggestion. However, could you suggest a brand of paint remover to try as there a lot of formulations out there? I’m definitely interested. Jim
I am a guitarmaker, and have used cocobolo on a number of guitars, both as back and side sets, and as fingerboards and bridges. I’ve never had trouble with gluing it, and have used PVA, hot hide glue, and “all-wood” epoxy, all with good success. I have heard a warning about pre-treating with solvents, namely that it can cause more oil to rise to the surface from within the wood, and so I have chosen not to use that method. What I do is I pre-treat the glue joints with a chemical paint stripper before proceeding. I figure it’s designed… Read more »
I’m a hobbyist and built a steel string guitar over 50 years ago. I used Brazilian Rosewood for sides and back and German Spruce for the sound board. I just used regular Titebond glue with no special preparation and it has held fine for all these years.
hi i am a guitar maker,,i use lignum vitae very ofter, it is a very very difiicult “customer” to glue, but since 3 months i started glue this one with cianocrylate, many times fretboards. i designed a big truss rod option specially for having less surface to glue, just 15mm sectors on the borders operation takes 15 minutes, and 6 grames of cianocrylate, it glues it mint, putting a good quantity of glue because it dries so fast that if bit glue, no time for pressing, but leaving a good hand of cianocrylate,,i press fretboard exactly 10 minutes and after… Read more »
if you are still around, can you tell me if the super glue held up. I was under the understanding that that glue is not good for a long time.
thanks
I cannot speak for the poster, but I can speak from experience.
I have had no bad luck with inlays that were small and held in with superglue like glues. However larger parts exposed to prolonged stress often do fail. It can make a real mess of a fretboard, as the surfaces will separate, but enough of the superglue will remain in the wood making it difficult for a different glue to grab in a repair.
good to know, thanks
The glue sounds like urea formalderhide, such as cascermite, a powdered wood glue. I think the only thing that may dissolve it is water, as some manufacturers recommend that the glue lines are protected if using out doors There is A bowyer who has had similar problems with oily woods when using this glue and manage to repair them. If the pieces have not comletely seperated and there is only a thin crack then use CA, low viscosity (super glue) If you wish to seperate the parts then steam may work. A red colourd resin I use called resorcinol (Phenol… Read more »
You can order it online.
I am trying to re-glue a Dansk rosewood bowl that has separated along several glue lines. The old unknown type of glue is white-ish and brittle and I have tried many solvents to remove it from the joints, but none has worked. I’d love it if someone could suggest a solvent to remove the old glue and also suggest an appropriate product for the repair glue up.
I glue up Ipe on a regular basis it is a very oily wood. I use Resorcinol resin as it is one of the only one that works well with oily woods. I used to Remove as much oil as possible using acetone but withe some pieces it would take forever and in some case end up more oily than after sanding. Even so resorcinol worked very well. Now sand the suface using 40 or 60 grit with a new belt where the grit is sharp. put a drop of water on a wast part to make sure it does… Read more »
p.s. THE WOOD DATABASE is GREAT!
I use it on knife scales and handles.
The joint is basically Gorilla glue and the two wood pieces clamped until dry.
I have had to router out a line joining both pieces on the backside of the project and used a length of bamboo placed in the routed line with glue to give it some added strength. So far this works. Since the backside is not visible it seems to work for when I have to use Cocobolo.
(maybe a picture would help to illustrate my joinery)
What are you using the Cocobolo for, and what kind of joinery is being used?
Other Ideas?
I have tried solvents to clean, rough sanding the surfaces to be glued and used Gorilla glue on Cocobolo.
It seems to bond well until heat comes into the equation which seems to cause the bond to release.
Any ideas? (besides keeping it away from heat)
As a boat builder and luthier Id never use a water based glue on oily hardwoods,its just not worth the trouble. epoxy only. my .02 cents.
Use epoxy, I recommend system 3 brand “silver tip” i have had good results with it on teak. you will have to cut the teak thinner than 1″ or it will not take that bend without breaking. Based on your pic and dimensions, i would try 1/2″ or thinner. If you do manage to make it work with the thicker pieces, there will be an incredible amount of stress locked in the part that will result in a lot of “spring back” and early failure. Make sure to wipe all surfaces to be bonded VERY WELL with solvent (acetone, MEK,… Read more »
I have a bunch of these laminated Larch Stands, but I would like to try the same design with laminating 4 1″ thick x 4″ long x 1.9m long Indonesian teak wood together into a curve. Does anyone recommend a type of glue that is fast drying and has a strong bond with Teak? Also does anyone know how much compressive strength would be the best? It would be kiln dried, Premium or A grade teak. Does anybody have any experience with something like this and think 1″ thick maybe too thick and would crack? Any recommendations are greatly appreciated.… Read more »
Hello. I am debating buying what appears to be a VERY nice used classical guitar whose Indian rosewood bridge has separated from the body’s top/soundboard which is red cedar. However, I am unfamiliar with exactly how to go about re-attaching the bridge to the cedar given the oil issues mentioned above. Logically, there must be a standardized type of approach to this issue since virtually all red cedar topped classical guitars have rosewood bridges and for them to rip up like this isn’t very common. I would seriously appreciate any and all information about the best way or a standard… Read more »
One of the suggestions I could make that if possible or when possible to mortise out a section of the two pieces being glued together and incerting another, glue friendly wood, to bond the two together. The mortise would be an inset so that the true wood would show and not the insert; if that makes sence? The inserted wood could be slotted in place like a dowel, or small screws which are resesed below the surface of the softer wood will hold it in place. Just thinking outside the wood box.
good day
about this 3 possibilities
1 poliurethane glue
2 epoxic glue
3 cianocrylate
which one do you think it is best for gluing hard woods between
in middle measured pieces???
(sorry if my english it is not the best)
thanks a lot
good afternoon i am just making some investigations about gluing hard woods here in colombia about amazonas you can easelly find out 50 species of hard woods worst of all it is lignum vitae and some very similar to that,, tabebuia impegitinosa or sapan for example i am highly interested on trying cianocrylate on fretboard joint and any non water based glue,, lignum vitae it is extremelly hard one that absolutelly do not tolerate any water based glue,,after 3 days starts to open, and gives a lot of problems,,if you add to this fact that this hard woods hot a… Read more »
Hello Ignitious
It is not possible, so you had better not try
Love from
The Internet
Hello
I love leadwood and i in my country it is not protected, so i wanted to make a log cabin, is it possible?
kind regards
Ignitious
Tropical hardwoods have tons of natural oils in them ,the oldschool trick of cleaning the surface with acetone still works great, just be sure to do your gluing within an hour but no less than 30 minutes. That way the solvent has gassed off and the oils have not started to return to the surface. West systems with the normal catalyst not the fast one. is my first choice, with a close second to system 3. Works on teak and cocobolo, Ipe, canary, and other rosewoods and bocote to name a few.remember dont over tighten your clamps bring it up… Read more »
Tropical hardwoods have tons of natural oils in them ,the oldschool trick of cleaning the surface with acetone still works great, just be sure to do your gluing within an hour but no less than 30 minutes. That way the solvent has gassed off and the oils have not started to return to the surface. West systems with the normal catalyst not the fast one. is my first choice, with a close second to system 3. Works on teak and cocobolo, Ipe, canary, and other rosewoods and bocote to name a few.remember dont over tighten your clamps bring it up… Read more »