Best wood glue for outdoor projects?

[Neocleous]

Hi everyone,

I am going to make a garden gate out of exterior MDF and I need to laminate two 15mm sheets together.

Normally I would just use regular wood glue and I’ve never had a problem with this on indoor projects but most wood glues are not outdoor rated.

I considered using PU glue as that is outdoor rated but I’m not sure if it’s expanding properties make it a poor choice for laminating two sheets together.

The other option I considered is contact adhesive but I can’t find a definitive answer on how weather proof it is.

Does anyone have any experience of doing something simul and have any suggestions?

Thanks
Dan

 

[Spectric]

Hi

I thought MRMDF is only moisture proof to an extent, will this survive in the rain. Some info

"They offer uniform thickness and a homogenous structure. They are resistant to moisture (MR), termite, borer and fungus. " and

" You may notice all of the applications of MDF are either as indoor components or pieces that are otherwise shielded from heavy exposure to the elements. It can not last in harsh conditions and should never be used for external framing and construction. Stick to heavy-duty lumbers such as plywood and OSB for these uses. "

personally I would use more traditional timber.

 

[Neocleous]

I’m not using MRMDF I’m using exterior MDF it’s a grade down from Tricoya.

 

[user22161]

I considered using PU glue as that is outdoor rated but I’m not sure if it’s expanding properties make it a poor choice for laminating two sheets together.

Epoxy stands up to most outdoor conditions and doesn't expand.

 

[Neocleous]

I hadn’t considered that!

 

[gmgmgm]

Can you just use exterior-rated PVA? I use D4 or "502" from Toolstation, which seems to work fine.

I haven't heard of using exterior MDF for a garden gate before, will be interesting to see how it turns out?

 

[MARK.B.]

Titebond3 would do the job, but if I were you I would think long and hard before using MDF of any type in an exposed outside situation like a garden gate .

 

[Phil Pascoe]

If you use PU you'll never clamp the two sheets together. 502 is excellent, but only D3. Use D4 if you go down that route.

 

[sawdustandwax]

Once made consider using a product such as bonda or ronseal wood hardener, it will cure using whatever moisture is in the mdf and will waterproof the gate. You can still use ronseal 10yr finish over the top of it. Not tried it with any other finish. You'll be amazed how much will soak in just keep applying till you get a film on the surface.

 

[Stevekane]

Be aware if using Toolstation D4 it comes in a 1ltr bottle and has a short use by date. I looked up your MDF,,,,it looks just like the regular stuff, a double thickness is going to make a weighty old gate,,,is there an artistic design element to this creation your keeping to yourself?
Steve.

 

[Neocleous]

I am using the exterior MDF to match a garage door and front door that was recently fitted. I am going to put tetrion power fill to all of the edges to seal them and the gate is going to be painted with zinsser exterior paint

For those interested this is the MDF I am using MEDITE EXTERIOR my use is well within its spec.
the gate will be heavy but I am not concerned about that as it will be more of a door than a gate with a bar handle and two locks and heavy duty stainless steel gate hinges.

 

[MARK.B.]

Very interesting, I never knew that they even made an exterior mdf but I do now,how much does the stuff cost ?

 

[Phil Pascoe]

Be aware if using Toolstation D4 it comes in a 1ltr bottle and has a short use by date.
Steve.

It has a fairly short date no matter where it's bought - the last one I bought from TS had a better date than the one I bought elsewhere before it. TS is expensive though, look around.

 

[Hattori-Hanzo]

Have used Tricoya plenty for external joinery work, it really is a superior material for painted external projects.
I've not used the Medite exterior you've linked to, but from reading it looks to be similar.

We only ever used a Phenol Resorcinol glue to bond it. They are exceptionally high strength and fully water resistant.
They are however quite expensive and care has to be taken when mixing and using as they can cause instant dermatitis and respiratory issues, Gloves and a high filtration mask is all that's needed.

The newer versions have a liquid hardener rather than the older style powder which is much better and safer.

I can't remember the name of the stuff we used to use but from a quick google I found this on e-bay.

https://www.ebay.co.uk/itm/173675079859
Before this "Cascamite one shot" was frequently used for external joinery, but the quality of Cascamite has vastly gone down hill since the Polyvine take over, lots of reports of bad batches which I've experienced first hand. This was a while ago so the issues may have been resolved.

Cascamite one shot can still be purchased a believe under the new name of "Aerolite one shot" Personally I'd still avoid the Polyvine stuff.

 

[Neocleous]

Very interesting, I never knew that they even made an exterior mdf but I do now,how much does the stuff cost ?

Well timber has shot up and it was about £80 a sheet for 15mm originally I was going to buy a 10 X 4 sheet of Tricoya which was about £240 per sheet when I looked at it but that went out of stock and 8 X 4 sheets went to over £300 per sheet! So I settled on the external stuff instead.

 

[Neocleous]

I think all things considered I'm going to give D4 a go as I would imagine I'll use a whole bottle to laminate the sheets together and I will screw the sheets together also and fill with a two pack filler

 

[MARK.B.]

Ouch that's expensive stuff, i look at my diminishing stocks of ply and dread the time when i need to buy more I find myself saving bits that would usually have ended up as kindling, and i try extra hard to get as many bits as possible from these before I cut into larger sheets .

 

[Hattori-Hanzo]

If you intend to screw the sheets I'd recommend the use of stainless steel screws, any others will eventually rust possibly causing the filler to fail.

Personally I'd consider using screws to hold the pieces together until the glue has fully cured, then remove them and fill the remaining hole.
A good quality glue will be more than strong enough on it's own.

 

[whereistheceilidh]

Have used Tricoya plenty for external joinery work, it really is a superior material for painted external projects.
I've not used the Medite exterior you've linked to, but from reading it looks to be similar.

We only ever used a Phenol Resorcinol glue to bond it. They are exceptionally high strength and fully water resistant.
They are however quite expensive and care has to be taken when mixing and using as they can cause instant dermatitis and respiratory issues, Gloves and a high filtration mask is all that's needed.

The newer versions have a liquid hardener rather than the older style powder which is much better and safer.

I can't remember the name of the stuff we used to use but from a quick google I found this on e-bay.

https://www.ebay.co.uk/itm/173675079859
Before this "Cascamite one shot" was frequently used for external joinery, but the quality of Cascamite has vastly gone down hill since the Polyvine take over, lots of reports of bad batches which I've experienced first hand. This was a while ago so the issues may have been resolved.

Cascamite one shot can still be purchased a believe under the new name of "Aerolite one shot" Personally I'd still avoid the Polyvine stuff.

Would endorse what you said about the strength and waterproof qualities of Phenol Resorcinol glue. we used it in laminating boat timbers......just was not aware if the health issues...... our tubs did not appear to have warnings. Might explain a few things.
BTW with the gate.....
...if you are using stainless & it is heavy structure, which looks likely, a lot of imported cheap A2 stainless fastenings are very brittle ...& often not that stainless over the years. Try A4 or from a reliable source.

 

[Phil Pascoe]

Before this "Cascamite one shot" was frequently used for external joinery, but the quality of Cascamite has vastly gone down hill since the Polyvine take over, lots of reports of bad batches which I've experienced first hand. This was a while ago so the issues may have been resolved.
Cascamite one shot can still be purchased a believe under the new name of "Aerolite one shot" Personally I'd still avoid the Polyvine stuff.

Aerolite is a different company to Polyvine. I've not used one shot, but two part Aerolite is an excellent glue.
If you need one part, use Semforite - Waterproof wood glue, UF resin powdered timber adhesive...Semforite, Resintite

(Incidentally I used Polyvine Wood OIl ........... which is nothing more than a varnish. If I never see that again it'll be too soon.)