Recommend me FLEXIBLE construction adhesive

[Marctrees]

Will be bonding dry clean warm wood to wood in shop environment.

Need good adhesion but most important - rubbery like flexibility.

End product will spend it's life indoors, BUT unconditioned in a very seasonal changing humidity.

Also, ideally color to blend somewhat w pine boards.

I need flexible because I will be bonding crossgrain boards and need to allow for future wood movement long grain bonded to cross grain yet maintain bond strength.

Thank you, Marc

 

[Marctrees]

Yes, I know all about wood movement R. Bruce Hoadley and all, and I know what I want to do is unadvisable, but in this case necessary.

Basically I need to glue 1x pine boards edges touching on a large piece of plywood ,,, and want the boards to be able to change in width w/o cracking.

Marc

 

[rlitman]

Use Titebond III in a well fitted and clamped joint. Forget construction adhesive.

Now for the technical answer. Titebond III (II also) is more flexible than the original formulation (and other typical yellow wood glues). You are NOT bonding long grain to cross grain. You're bonding long grain to PLY. That's a huge difference, and one that acts in your favor.

Normal wood changes in dimension a lot across the grain, but very little with it. Ply acts more like long grain in both directions. So, bonding long grain along ply will work just fine. This is done all the time. For example, using a small strip of real wood to edge plywood shelving, or panels in furniture.

As for bonding long grain against end-grain, that's a technique that's encountered on breadboard ends, and a spline or dowels are often recommended. In your case, I'd recommend biscuits. That should make up for the deficiencies of the fact that the glue joint is not a completely true long-grain connection.

 

[Marctrees]

Well, I wil also be bonding pine 1x's at 90.

Like board and batten doors.

I do currently use TB 2 for all other projects.

I definately want wayy more flex than TB.

TB3 may be more flexi, but I want actually rubbery.

Just plain RTV silicone would work, but the adhesion to wood is not that good.

Marc

 

[Marctrees]

r - I am very familiar w movement and the details and theory of breadboard.

For what I'm doing those solutions do not apply.

I need the rubbery flexi adhesive.

Marc

 

[Marctrees]

In the glued on ply situation - I am only concerned about the cross movement.

We agree.

Marc

 

[Marctrees]

Although there may be other solutions, the adhesive would work overall best for production efficiency reasons.

Marc

 

[rlitman]

Well, I wil also be bonding pine 1x's at 90.

Like board and batten doors.

I do currently use TB 2 for all other projects.

I definately want wayy more flex than TB.

TB3 may be more flexi, but I want actually rubbery.

Just plain RTV silicone would work, but the adhesion to wood is not that good.

Marc

The difference between TB II and III is minimal. If you already have II, stick with it.

Joining pine 1x's at 90 requires a traditional joinery technique. Mortise and tenon, bridle joint, half lap. What do you feel up to, and how much force will it need to handle. Do you have a biscuit jointer? That not the strongest option, but it might be the simplest.

Epoxy is also quite flexible, and bonds much more strongly than RTV. It's a better gap filler than yellow wood glue too, but gaps ALWAYS mean reduced strength.

 

[rlitman]

In the glued on ply situation - I am only concerned about the cross movement.

We agree.

Marc

Yep. Ply doesn't have significant cross movement, so you're good to go. But because you're only long-grain bonding to half the surface area, a biscuit can prevent failure down the road.

 

[Marctrees]

r - I understand and agree with you.

But in this case I am looking for my original question.

Not disregarding you at all, appreciate your input.. just saying in this case I need what I asked for.

Marc

 

[rlitman]

r - I understand and agree with you.

But in this case I am looking for my original question.

Not disregarding you at all, appreciate your input.. just saying in this case I need what I asked for.

Marc

Understood. I'm just not convinced such a material exists. Epoxy would be the closest thing I can think of. It will easily meet your flexibility requirements, and the tensile bond strength is as good as it gets, but I don't think that will be good enough.

 

[Marctrees]

yarrrrrrrrrrr

I know the PLY is stable... but my face glued to it pine is not and will move in width in the future bigger than typical MC swings it will encouter long term.

I need them to be free to move yet still stay adhered to the ply.

My 1x6's will change within maybe even 3/16 in width of the 5.5".

They need to be free enough to do that w/o splitting, AND yet stay stuck.

Marc

 

[Black300zx]

I notice you requested that it cosmetically blends with pine boards. What is the end application? If cosmetics are important, could you give the entire finished assembly a coat of paint if the adhesive is off-color?

My favorite flexible adhesive is 3M 5200 marine sealant (fast cure formulation). It's white and can be very messy if you don't make it a point to regularly change gloves, but I've yet to find a material that it won't bond to extremely well. It also takes paint well and is fairly flexible. I've personally used it for repairing rips in urethane car bumpers with great results.

I don't know what your end application is, but it might be worth trying it on a sample to see if it suits your needs.

 

[MoonRise]

3M 5200 - cure time 5 days (heard it referred to as "Satan's Snot" )

https://www.3m.com/3M/en_US/company...ive-Sealant-5200/?N=5002385+3293241623&rt=rud

3M 5200 Fast Cure - cure time 48 hours

https://www.3m.com/3M/en_US/company...t-5200-Fast-Cure/?N=5002385+3293241048&rt=rud

 

[MoonRise]

Sounds like you would want something in the 'construction adhesive' type and not necessarily the 'wood glue' type.

So, a urethane or polyurethane construction adhesive.

Go to the Titebond website and use their 'picker' to get some possible options. Or call them. Or call 3M or dig through their website.

http://www.titebond.com/product/adhesives/244021b4-7d47-4b78-8efd-ebef0bf67647

http://www.titebond.com/product/adhesives/f29013a3-8db0-4b81-b308-46eef40bd3c5

Picker:

http://www.titebond.com/guide/question/0/0/adhesives

 

[Marctrees]

All I want is "Construction adhesive", caulk gun tube, that is cream to light tan, but is more flexible and stretchy than const adhesives I have seen.

Dry or cure time of 5 days is a problem... need more like 2 day or so for most strength.

Either solvent or water based is fine.

Cleanup needs to be like typical stuff, nothing crazy like Gorrilla glue.

Marc

 

[Marctrees]

Moonrise - Will look now.

Marc

 

[strutaeng]

How about polyurethane sealant? I think they are able to expand to 150%.

Sealant will also bond to raw wood very well.

Or that 3M Marine adhesive? It actually meant for wood that gets get and moves. Check out the technical data sheet:

https://multimedia.3m.com/mws/media/576967O/3mtm-marine-adhesive-sealant-fast-cure-5200.pdf

 

[Marctrees]

Gonna get a tube of this and test it.

Also Lexel.

Marc

https://www.sashco.com/products/big-stretch/

 

[Black300zx]

3M 5200 - cure time 5 days (heard it referred to as "Satan's Snot"

I've never heard that one before, but it sure is a great description! I think I'll have to start using it

 

[tarbellb]

Look up Sikaflex and Dow 99X family (995 comes to mind), both are very strong sealant/bond. Not sure about colors though.

 

[steel 35]

Look up Sikaflex and Dow 99X family (995 comes to mind), both are very strong sealant/bond. Not sure about colors though.

I have ten tubes of 252 tanish color too.

 

[dwysywd]

Solar seal best stuff ever. In a situation where it’s not out side but has humidity as an issue, treat it like it’s outside. I’ve used this stuff for every thing you can imagine and even things it was NOT intended for and it’s never let me down...ever. Just my $0.02



Sent from my iPhone using a facsimile machine.

 

[Firstram]

I have used cases of NP1 for exterior trim work on beach houses, lots of colors to choose from. On red cedar shake siding with mitered outside corners the joint will still be solid after the shingle has almost worn away.

Invest in a good high leverage caulking gun!

 

[theoldwizard1]

Will be bonding dry clean warm wood to wood in shop environment.

Need good adhesion but most important - rubbery like flexibility

Don't laugh, it works ! Amazing Goop/Shoe Goo !!

I swear they are the same just different packaging. Very reminiscent of "rubber cement". Comes out very thick and sticky. Do not squeeze the joint to hard if you want it to flex.

 

[kerrynzl]

Will be bonding dry clean warm wood to wood in shop environment.

Need good adhesion but most important - rubbery like flexibility.

End product will spend it's life indoors, BUT unconditioned in a very seasonal changing humidity.

Also, ideally color to blend somewhat w pine boards.

I need flexible because I will be bonding crossgrain boards and need to allow for future wood movement long grain bonded to cross grain yet maintain bond strength.

Thank you, Marc

PVA glue [Polyvinyl acetate]
Flexible wood glue that cleans up with water.

 

[NORDFORD]

I have used cases of NP1 for exterior trim work on beach houses, lots of colors to choose from. On red cedar shake siding with mitered outside corners the joint will still be solid after the shingle has almost worn away.

Invest in a good high leverage caulking gun!

I second NP1. Should be perfect for your application