Titebond III testing
I have about finished some pretty extensive testing of this adhesive, as it compares to Resourcinol, and PL brand polyurethane adhesive (in calking tubes). From a variety of immersion tests and breaking strength tests, and using white oak and yellow pine as test species, I am able to see a slight advantage in the purple stuff, but only in the immersion category, and even here the advantage is slight (To help qualify what this means, once sample assemblies were soaked for two months and then broken apart the resourcinol broke with more wood fibers pulled out from the adjacent piece. The Titebond III also pulled original wood, just not quite as much of it.) I also have results from both lightly clamped (10 lbs force) assemblies and heavily clamped (traditionally the advice of resourcinol advocates) assemblies and at a variety of grain orientations relative to the mating piece. It seems best to use a fair amount of force with both materials, but Titebond may be a bit more flexible.
The entire test plan is quite extensive and I've no plan to clean up the data for publication. You shouldn't trust implicitly what anyone else says anyway if you have pride in your work. This is just to let the community know that you might want to revisit (if you aren't already using Titebond III) the adhesive yourself for possible applications. I am impressed. I am not saying anything about the PL stuff. It has its uses and I even make good use of it myself quite a bit: I'm just not going to put it in any boat that I build.
OK. Time to get back to the lofting, though my knees could use the rest of the day off.
way to go
I am looking for a glue that could replace both epoxy and Res in a build I am organizing now
couple of questions
T Bond I always let sink in for a moment or two before assembling the parts
and once placed I always make sure that the clamps are just hand tight and not to crank them as hard as I can so as to leave glue in the joint
would you agree that that is the correct procedure
or did you follow a different procedure in your testing process
thanks for posting your results
points to you mate
this is a thread Ive been waiting for
I'm interested to hear all about your tests, as I'm just finishing a project using Titebond III. So far it sounds like your results are favorable (which is good news for me, I guess).
The small boat I'm building is assembled entirely with TB3. Clicky. All joints in the frame and the butt joints between the planks are glued with the stuff. Now, everything is also screwed, so you could remove the glue and it'd hold together. I've also used the TB3, mixed with wood flour, as a filler, which seems to have worked well (it already has such a high solids content).
I can't comment on the moisture resistance (the boat'll be dry sailed and pretty well sealed) but your comments reassure me. What I have found are a few minor things. When sanding, TB3 gets quite soft from the heat, which can be a pain. It isn't much different than normal wood glue in this respect. I've also seen it do some funny things in cold temperatures that are technically within the rated range.
Also, I've read that TB3 is a poor choice for applications under constant load (oops) and that it will fail suddenly, rather than gradually. Anyone have any experience with this?
Are you going to share any more details about your moisture tests? I know we'd all love to see them.
Cameron D. M.M.
Tite Bond III is rated a type I water proof adhesive. It just passes this requirement in several of my own tests. I've used Tite Bond III for several years with good success, but would never use it in highly loaded or under the LWL applications.
It does seem to fail catastrophically under high loads and isn't recommended as a structural adhesive by it's manufacture, likely for this and other reasons.
Lately, I've been testing it as a coating and results are yet to get in. It's cost and easy of use are real benefits. I've tried using fillers of different types and percentages, but haven't succeeded in making it workable without a lot of "grab" lose. It does appear to be slightly gap filling, though quite small gaps only and shrinkage is an issue.
You have to be careful about this stuff though as it's difficult to repair. Epoxy doesn't like to stick to it.
Hey Par, could you describe a bit more of what you mean when you say 'coating'?
I know that I chose TB3 for it's cost and non-noxious-chemical-ness, as I had to work indoors in a living space that shares ventilation with my living quarters. The clean up was nice too. I think for some people, myself included, these are strong benefits.
You are right that shrinkage can be a problem when filling, but I mostly ran into on larger gaps. I'm sure that our ideas of what is a small/large gap differ (my boat is only 9 feet long, after all). What do you mean by "grab lose"?
Also, thanks for the tip about epoxy. I hadn't expected that, and will need to consider it.
Finally, sorry for hi-jacking your thread longfellow.
Cameron D. M.M.
Regarding polyurethane adhesives, sold as construction adhesive for subfloors, etc., I am using this glue for certain applications on a kayak frame I'm building. Specifically, i'm using it to bed slash-cut 2 1/2" height gunwales to solid wood stems. I am using screws for primary attachment. The glue is a means to ensure the joint is unable to hold moisture, and to also guarantee the screws cannot "work".
I am also using the construction adhesive to bed the deck cross members to the sides (gunwales). This kind of application was also to augment the primary screw attachment.
I had the opportunity to test the bond when replacing two beams due to a design change. After removing the screws, I sawed through one side and tried to snap off the beam from the other side with a pressure just short of pulling the wood off the gunwale. After failing, I decided to saw the second side and belt sand the stump that remained. Bottom line, end grain joints aren't that good with most adhesives besides epoxy, but you might try construction adhesive (mine was a super-strength type costing 2 1/2 times what the cheap stuff cost--$5.75).
I'm tempted to try Titebond 111 now, as I've been using gorilla glue for laminating strips to make an arched deck beam, and to scarf strips to make a coaming. None of this will be under water nor allowed to remain outdoors between uses. Epoxy isn't needed nor wanted if a no-mix solutiuon can be found. It's not the cost but the pre-mixing, which guarantees waste, while single part glues can be added to if they don't finish the job.
Thanks for sharing the research.
ya great thread topic
this ones got all my attention
in the type of joints that I tend to make the structural loading is whats called a dead load
( at least in the joint the beam itself in this picture is live loaded )
when I use Titebond ( and I been using it for ages ) I have had no problems when its applied to this type of joint
here you can see how the joints fit together
its a half blind tenon in a mortise or a stopped dado ( take your pick someone is sure to call either wrong )
least thats they way I learned it
that will be pinned with a oak dowel
i dont use metal fasteners so there are no metal fasteners to work in any of the stuff I build
basically when joint is made of wood it will flex evenly
when a joint is held with metal
since the metal is harder than the wood it will chew away at the surrounding wood no mater how well you made the joint and eventually work itself loose
metal and wood do not flex uniformly
Ive hesitated to mention this on the forum cause Im sure a number of people will jump down my throat for it what with the method being so old school
but it worked for generations of boat builders in ships that lasted a hundred plus years and more
so if that plywood boat screwed and glued lasts a hundred years feel free to spray paint "I told you so" on my head stone
Im going to get my head chopped off for this but a properly cut pin with a nicely tapered head will outlast any metal fastener if made out of the same wood as what its fastening to and properly cared for
metal no mater what you do will eventually eat away at the edges of the wood in contact with it and become loose over time
galvanic action isnt exactly conducive to longevity either
back to glue
I never used much glue but when I started making furniture I discovered Titebond and been using it for years
what ive found
( and I have not tried the stuff in any underwater applications )
is that its pretty tough if you clamp the joint properly ( not to hard not to soft )
Ive only ever had one joint fail and I dont think I clamped it all that well
so could have been my fault
funny part was that I was telling someone how tough the stand was when I grabbed and shook it with everything I had
normally nothing happens but in that one instance there was this big bang and I knew I had lost a joint
the stand still held and nothing else happened other than me standing there looking stupid
fortunately the tank was mine and not one I had made for anyone
I am eagerly awaiting Par's answer though cause I never mix glues and when I come across a hodge podge of different glue in one joint I always clean the crap out of it and start over if I can
or maybe even make a few new pieces and just start fresh
the joints in this picture are whats called bridle cut and again there is no metal fastener needed in this kind of joint
its dead loaded in the joint at least although obviously the beam is live loaded so the stress in on the joint and not on the pin
I cant seem to find any pictures of the pinning process or placing the risers
risers being that vertical piece on the right hand side middle of the picture
thats held in place by twin feather tenons
the work is a fish tank stand and will be holding about 2500 lbs
Ive never had one fail
and Ive never once used any metal fasteners of any kind
they depend entirely on old fashioned joinery
and a little glue
Tite Bond III is pretty good in compression, not very good (compared to many others) in tension or sheer. It also doesn't like cyclic loading much, but if movement is minimal, it'll hold. For these reasons (and others) I can't trust it in structural applications or places where I know it'll be in tension, sheer or have to tolerate movement.
Cameron, when I added fillers to bulk up the glue, it lost much of it's "tack", which is one of the nice features of this adhesive (quick tack). I found I was wetting it out with neat TB3, just to get it back, which literally watered down the filler. I've never expected it cover very large gaps, a 1/16" would be as much as I could ask, with considerable shrinkage to be anticipated.
Like all of the modified aliphatic resins, it has it's limitations, but it also has it's uses and I'm finding more all the time.
Boston, you experienced the catastrophic failure I mentioned. Your joint which was in sheer, just confirms my testing. It's kind of weird, they just give up, usually with a loud bang. I've seen very old resorcinol joints do this under load, but the glue had turned to powder and it was obvious from the looks of the glue line, that it would eventually happen. The TB3 failures haven't given me these warnings.
well I am avidly reading along cause I want some kind of option to my old school ways and the modern glues like epoxy or Res which I know are just horrible on both the environment and on the person living aboard
I am disappointed that Titebond wont work for my build
joints in a boat are under stress in every direction at some point in there life time
I think that the sound associated with the failure of Titebond is due to the pressure originally placed on the joint by the clamping process being suddenly released
or maybe the swelling of the wood in different moisture conditions placing enough additional pressure on the joint that once an additional force in an unfavorable direction is also applied you end up with a sudden failure
I been wondering if the same characteristics would hold true for this type of glue depending on its moisture content
if it were in an immersion situation would this type of failure be more or less likely to occur
Good information folks.
Great looking workmanship ! I sympathize with your fear of attack here. Everyone has an opinion right? But you've got the right idea in challenging some of the ideas that you hear and read. This is why I humbly invite everyone to do their own investigation. Regarding clamp pressure, you're right on. Use moderate pressure. Your woodworking instincts are all you need and it is too difficult to try to write about how to do it. Yes, I would allow a minute of soak time but only because we are always gluing variously different faces (radial, tangential, or somewhere in between) and they soak up glue differently. I just give every joint a minute or so. Finally, your technique of trying to end up with a truely homogeneous assembly with no single component (metal screw) having drastically different mechanical or thermal properties, is fantastic. We just can't dowel and biscut everything in boatbuilding. We'd never get done
Good point about the actual mechanical strength. I only did destructive testing that would approximte sheer loads (with and also across the grain). I do what I can to make sure that there is no joint that is truely in pure tension. Neither would I think that true fatigue loading (the general category that cyclic loading falls in, as well as reversed cyclic which is even worse (This is vibration.) exists anywhere in a boat except maybe on engine beds and surrounding structures, so I don't really worry about results. I am only building daysailers without engines so I don't think I need to worry about performance under fatigure loads. But now that you've mentioned it, if I ever were to consider hanging an outboard on a transom, maybe I should be more concerned. Do you have strength data on the two materials? I'd be curious I guess about tensile, pure sheer, and fatigue strength values if you have them as well as the "many other" types of adhesives that you mentioned were better. I still have some time to repeat the testing with whatever you suggest, before I am going to actually need to 'cut bait.' The lofting is almost done. Thanks,
Thanks Ed for the response
you would be surprised how fast pinning goes once you get it down and the quality of the joint is tops
although I did have one fail
once that I know of
the time consuming part is in making proper pins not the actual application of the pins as you would in many cases be pre-drilling screws anyway
fluting em is what sucks and my grand dad would have us turning out pins for days on end sometimes
I dont use biscuits either but instead true feather tenons
the biscuits are flimsy and just not big enough
besides I kinda hate plywood
so I make a nice feather out of stock and use the old scantling rules for size
a joint made this way can potentially last a hundred plus years and historically nothing that I am aware of can beat that glue or no glue
when I get my materials all together and start my build Ill post some pictures of the pinning process
my old grand dad Roby taught us kids how to build according to what his dad had taught him and Im kinda partial to it
not sure if I just like the nostalgia or if its the simplicity or what
just kinda feels right to do it that way
I actually started writing a short on the old school joinery techniques
maybe someday Ill post it if I ever get it done
nice quote from H by the way
has a ring to it
I want it to be more than the sum of its pieces
and I want each piece to be a pleasure in itself
sounds like thus far Im still stuck with epoxy
should I decide to use glue at all
It's going to be really hard to replace epoxy with any one part adhesive. The properties are just ever so tailorable to whatever adhesive bonding/laminating job you happen to have.
The environmental and health concerns are wholly addressable by simply selecting the appropriate curing agent as it's the curing agent that has all the serious health issues (there's no epichlorohydrin left in epoxy resin after epoxidzation; most resins are not even classed as hazardous.)
There are literally hundreds of curing agents available. Most users of epoxy content themselves to using a 'system' (resin + curing agent) off the shelf rather than formulating one for themselves. This approach works OK as long as what you want happens to be right in the middle of what's easy/economical/profitable for the re-sellers to provide.
Most formulators will not offer a 'very low toxicity/sensitizing' resin system since it will cost more than one that uses curing agents that are poisonous/sensitizing, and the more expensive product line (which provides no other benefit) will just sit on the shelf unsold next to the typical product.
Virtually all the epoxy resin systems, regardless of curing agent used, can be totally inert, and not outgas any volatiles and can even approved for food contact ONCE FULLY CURED. The volatile modifiers can change this picture by adding a component that may continue to outgas later. Resorcinol modified epoxies also will outgas.
So why use these modifiers to begin with? AGain, the answer is mostly cost. The use of the modifiers can again be eliminated by selecting a better resin like BPF instead of BPA, as the BPF tend to b lower viscosity. But it is once again cheaper to make a system with BPA + volatile modifiers to thin it out and a cheap and nasty amine curing agent like TETA, than to use the thinner BPF resing and a polyamide or some such and price is all anybody ever buys on.
Look how many threads there have been recently where someone asks "What's the CHEAPEST epoxy around?" It's never "What's the lowest toxicity/sensitizing resin system around?"
I got into formulating epoxy about 10 years ago when I needed a resin system that nobody offered 'off the shelf' yet, as I was building carbon masts. That's all changed and now there are resin systems that if available 10 years ago, I could have put to use instead of learning about formulating, something that I have never needed since.
I use plywood or same-wood splines now (both sides mortised) if doing cabinets for kitchens, etc..
Depending on what the job was (most of what I've done has been cabinets), I would avoid both biscuits and whatever they're called--- the screws angled from behines stiles and rails. Seems there're a lot of new systems.
Like you, I'd go with old world methods if the piece was worth the effort. Through tenons with wedges, wood pins slightly offset to draw the parts together, or whatever method made a lasting joint.
I dont mind glue in a joint
but the joint has to be able to hold with or without the glue
a pinned feather tenon will always hold
as will tree nails or a true suicide lock ( stopped tenon with a wedge, very tricky to do properly )
a through tenon wedged is called a fox lock ( much easier to do )
or at least thats what Roby called it and he was an old school trained shipwright his father having come from Bristol
I think we are on the same page concerning joinery
the thread is about glue
so enough of this nostalgia
and no more about our joinery skills
I just wanted to point out that in certain joints certain glues seemed to work fine
( although it was news to me that Titebond sucked as a ship building glue, and Im disapointed but glad to be aware all at the same time )
but for bellow water applications and in many boat building applications simple joinery has been augmented by some pretty dam good glues
which I know nothing about
lets not distract from what is a great thread about glue and its applications by people who obviously have us both beat on the glue issue
so whats the verdict
Jimbo seems to have some good points about epoxy
and Edd seems to have done his homework on the empirical end
so what do we have to work with in the end
sounds like epoxy or Res
with PL being a close runner up ( maybe )
can I or cant I use PL for below water applications
and if I dont use it all I can always cap it for use in the future
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