Your Favorite Adhesives

[DeValency]

All adhesives mentioned are great for their intended use. There is no one for all, so I keep at least 15 different products on board, where 5200 and 4200 are always the most used sealants-adhesives.

* MarineTex, although darn pricy is the best I've found yet for Hypalon inflatables
* As for epoxy; West and TotalBoat are always here in few viscosity and hardeners versions but so far my favorite epoxy is actually MAS

[thinwater]

Originally Posted by Stu Jackson

tw, don't have a copy or photo of the JBW, but my photo says it was blck and white tubes to mix.


Here's the Devon:

The JB Weld products are epoxy. Not great for plastic.


The Devcon product you show is an all-purpose epoxy. Not that great for plastic either.


Devcon Plastic Welder, on the other hand, is a methyl methacrylate adhesive (MMA), very good for plastics. In fact, it it Plexus MA-300 in different packaging (Devcon and Plexus are both ITW brands, so this makes sense).

[rossdv8]

In Australia, Selleys have a product called Selleys Wet Area Silicone Sealant.
I've used it on all my yachts and small (16 foot) surf cats.

This Wet Area version' of silicone sealant is the only product I found that could stop leakiing cabin windows while they were actually leaking. I've used it to seal a hole in the hull sufficiently to get me 50 kilometres back to a safe place.

My boat builder hated silicone sealant on yachts because once it bonds to fibreglass - it stays bonded and acts like a release agent when you want to glue resin to gelcoat if you are not aware it has been used.

It glues timber, plastics metals and even glass to themselves and to each other. (Big aquarium fish tanks used to be glued using Silicone Sealant)
It can hold stuff to masts, and seal through-deck leaks.
I have used it to patch large rips in sails (combined with a bit of stitching here and there).

For more than 20 years I never went anywhere without a few cartridges of the stuff. It was about $4 to $6 dollars for a 330 gram cartridge back then.

I tried Sika when it came out, and a few other things. Always went back to this stuff. It smooths into place with a wet finger (before it cures) and any mess cleans up with vinegar (eventually) before it completely cures.

To give an idea of its strength, for years in Australia Silicone sealant was used to hold those reflective ' cat's eyes' onto the bitumen road surface.

[David Mathis]

Our 100 gallon water tank">fresh water tank cracked on an end near the bottom (not a defect, it was damaged). A V was cut into the crack with a Dremel tool then the crack was heated with a pencil torch before using a hot glue gun to "weld" the crack. It completely sealed the leak. Other glues or substances may have worked but the hot glue application is successful.

[ewsponberg]

Originally Posted by thinwater

a. Epoxy has been done to death on a lot of threads. We all know about it.


b. Is West Systems that much different from System 3 etc, or is it just superior marketing? I believe the latter.

WEST System epoxies are my go-to adhesives for laminating and structural repairs. They are quite different from System 3 epoxy. WEST epoxies have a tensile elongation of 3.5% to 5.5%, whereas the System 3 epoxy has a tensile elongation of 2-3 times that at 11%. By comparison, polyester resins typically have a tensile elongation of 1%-2%, meaning they are quite brittle. That is why gelcoat cracks appear so easily--gelcoat is made with polyester resin. WEST epoxy has enough extra elongation that it does not crack so easily and so can mix well with a variety of fibers and fabrics. System 3, in my opinion, has way too much elongation with allows laminates to stretch too much and which can lead to other problems.

The other adhesive that I really love from the US is Shoe Goo--great for repairing shoes and a bunch of other things. Where we are currently in Australia, the equivalent is Shoe Fix. These are clear, highly viscous glues that start curing immediately on applying, and they render shoes somewhat waterproof.

Elmer's Wood Glue is amazingly strong for any wood repair projects. Contact cement of any type is also very handy.

That's my 2 cents worth. I hope that helps.

Cheers,

Eric

[rossdv8]

Originally Posted by David Mathis

Our 100 gallon fresh water tank cracked on an end near the bottom (not a defect, it was damaged). A V was cut into the crack with a Dremel tool then the crack was heated with a pencil torch before using a hot glue gun to "weld" the crack. It completely sealed the leak. Other glues or substances may have worked but the hot glue application is successful.

I keep a couple of soldering irons that are powered by AA batteries in various places, in the home, in my HiAce and I used to keep them aboard the yachts for quick electrical repairs..

I found they worked in a similar way to the post above when I needed to repair things like poly-plastic drums and water tanks, and the kayaks.

I little bit of irrigation type black 'polypipe' can be shaved to fill cracks and welded into place by melting the crack and the poly together. Obviously it works better if you can find more of the actual plastic you are welding.

I suppose that is similar to using the hot glue gun.

[ChrisJHC]

Apologies if this is covered up-thread, but has anyone tried the “UV-setting” glue that keeps popping up in my ads?

This is basically the same concept as the material that dentists use that sets with the application of UV-light.

According to the blurb, one drop would be enough to hoist your whole boat. Maybe that’s just marketing oversell

[flyingfin]

JB Plastic Weld 2-Part epoxy. Take a cotton ball, soak it with JB Plastic Weld and fix any hole, roll the cotton ball smooth, soak it and hold two pieces of any plastic together forever.

[ParL]

Originally Posted by s/v Jedi

Standard part of our medkits. It has been used extensively, I believe it began during the Vietnam war. On Amazon you can buy sterile version (I thinks it’s all sterile but okay) when you search for 3M Vetbond, which is what we carry. The one time I used it for a minor cut in my finger, I used regular CA which was at hand and I remember it got hot. Almost glued extra fingers.

Last I checked the main problem with the hardware type stuff is that there is no check for the compounds that are released when it hardens and while it is exposed to the body[1]. Probably not a major issue for small, occasional surface wounds.


But some sources points out that the formulations (hobby/medical) are different[2]: the hobby stuff degrades quickly in the body and release toxic compounds (iirc formaldehyde).



Oh, and in some cases it can cause burns[3]: there is a lot of heat produced when used on some fibrous materials.





[1] E.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4913938/
[2] Superglue - cyanoacrylate - Molecule of the Month - July 2009 - HTML-only version
[3] https://pubmed.ncbi.nlm.nih.gov/28054930/

[Thumbs Up]

Originally Posted by DeValency

All adhesives mentioned are great for their intended use. There is no one for all, so I keep at least 15 different products on board, where 5200 and 4200 are always the most used sealants-adhesives.

* MarineTex, although darn pricy is the best I've found yet for Hypalon inflatables
* As for epoxy; West and TotalBoat are always here in few viscosity and hardeners versions but so far my favorite epoxy is actually MAS

You mean this stuff right:https://itwperformancepolymers.com/p...e-tex-flexset/
Because when I think of Marine tex, I think of this stuff:
https://itwperformancepolymers.com/p...x-epoxy-putty/
I don't like marine tex putty because it is 5 to1 and unless you are using a gram scale, you have to eyeball it.
As for the Flex Set, it appears similar to West's G-flex (which I don't think has been mentioned). G-flex is great for lots of stuff. You can repair polyethylene tanks and kayaks (flame treat the plastic first). I use it to repair Teak (is amber colored) and anywhere I need a very small amount of very high quality resin (1:1 ratio is easy to eyeball). For dinghy repair is tricky because it takes awhile to cure, but for pinholes in an old dinghy I would just apply a few drops and cover with a square of duct tape. I would then leave the duct on.
I have heard of people using Krazy glue for dinghy patches, anyone try it?

[s/v Jedi]

Originally Posted by Sailorman97

Nonsense. You are never going to use debond to get a keel off. It would take gallons of the stuff, weeks of time and is of dubious effectiveness anyway. I tried this product years ago. It seemed it was designed to make money for the manufacturer and not much else.

How would you get it into the keel hull joint which is at best has a gap that is varying from nothing to 1/8-1/4" and is 9 inches wide at the widest part of the keel.


5200 and 291 are different formulas of similar ingrediencies. They are not the same.

You always know that if you can get Sika 291 out of the tube it is going to harden. This is not always true of 5200. It does not take long using google to find out this can be a problem.

I have separated fiberglass parts bonded together with Sikaflex 291. I have never managed to do this with 5200 except at the destruction of one part or the other.

If I know the part must be separated at a later date or parts that are going to be subject to movement I use butyl tape. It never hardens. This is not the same as butyl caulk you use out of a tube from Home Depot. That stuff hardens and then cracks.

You of course are welcome to use whatever you want. I use Sika 291 for most adhesive work. It has never let me down.

So you used 25 saw blades to cut the keel off that was put on with Sika 291 but think 5200 is bad?! Common now, do you really think it would have required more saw blades? Or saw blades don’t cut through 5200?!

I have seen DeBond in action: it works, period. No it won’t take the keel off in one go, but after brushing it on, even a 3-in-1 tool can rake it out to 0.5” deep or so. Rinse and repeat, like you did with saw blades

[Thumbs Up]

You can saw through these tough sealants using steel cable or heavy nylon string.

[nhschneider]

When we were cruising in Australia, we met a man with a PhD in chemistry who worked on the development of 3M's 5200.
He was very skillful in all aspects of boat building and repair. When our hypalon dinghy developed a leak, he offered to fix it using a patch of hypalon fabric and 5200, which he then hit with a heat gun. He claimed the heat gun not only caused the 5200 to cure more quickly but also made the cure stronger.

Fair winds and calm seas.

[hirondeller]

Anyone try this? 'Sikaflex Pro', I am only a consumer of this product and have no contact or affiliation with Sika. It is Labeled Sikabond Construction adhesive. Model #505423. It also comes in a 10oz tube, Model # 106403.



At the 'big box' stores in the US it is ~$19.00 for 29oz. Look for a green label and read carefully, there is a bewildering array of similar looking Sika tubes at the store. The Sika polyurethane is ~3X less in price compared to 5200; is that because construction workers are very price sensitive compared to 'Yachters'?


I find the two adhesives to be similar, the applications seem identical. It paints well. This Sika is gray (not white like 5200). The Sika is somewhat less viscous than 5200 and sets up a little softer. It claims to be truly waterproof and can be immersed after fully curing. Only 5200 and epoxy adhesives make this claim, the rest of the adhesives (including Titebond III) do not make water immersion claims on their labels.



I use it as a replacement for 5200, so far so good. I keep the giant tube (you will need a 'big' construction sized caulk gun for the 29oz tube) carefully capped and sealed in the refrigerator, it keeps about 1-2 years that way.


I also used it to repair 3 separate flats on my bicycle inner tubes, so far (2 years) no failures! Flat repair is a very demanding application because the adhesive must expand and contract as the tube changes size; will this be good for inflatables using a cloth patch (thoroughly smeared on both sides deep into the cloth?). It is also useful as a general purpose caulk and sealer on the exterior of my home.



On a big job (I am going to bed all my replacement Lexan windows on my catamaran with this) the price is compelling. I will post a 'new string' follow up, on the windows.


Please share a post if you try it.

[flightlead404]

Originally Posted by thinwater

Epoxies (including thickened) and polyesters are obvious.

Originally Posted by thinwater

a. Epoxy has been done to death on a lot of threads. We all know about it..

Don't skip the "obvious" stuff, or the things you *think* "everyone" knows about

Us newbies don't...