Epoxy for tru design thru hull

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roblpm

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Got the old through hull out!

New one seems to fit perfectly.

The instructions say put some epoxy between the flange and the hull (its a flush one so we need to chamfer a bit of the hole). Instructions say use west and powder.

No as i have no clue and just need a blob does anyone have specific products in mind that i could buy? The chandlery has a whole aisle of epoxy stuff!

I think its butyl tape or sikaflex on the thread.
 
First, the instructions tell you what to use on the threads, and it aint' butyl or polyurethane.

As for the epoxy, I think they've lost their minds, but that is what it says. That they say "tip" about adding powder and do not suggest a type strongly suggests they have not actually done this work or serviced them later. If I were you I would go to the Forespar Marlon (also nylon) site and follow those instructions instead. These are silly. Of course, Forespar does not say which Sika or Boatlife products, and some are not appropriate. So much for instructions.


True Design
Sealant:
Use Epoxy West System or similar 2 pot epoxy to ensure a water tight and strong mechanical seal between the hull and Skin Fitting. This method effectively makes the skin fitting part of the hull.
Tip – adding powder to the West System will help minimize “running” of the epoxy.
Fitting:
Coat the Skin Fitting with epoxy only over the length of the thread that will suit the thickness of hull, and also on the underside of the flange.
Push the Skin Fitting into the hull from the outside. The epoxy should hold it in place whilst you reposition inside, or alternatively, use a piece of masking tape to lightly tape the flange to the outside of the hull.
Hold the Skin Fitting in place and drop the supplied washer over the Skin Fitting followed by the nut.
Tighten nut by hand with enough pressure to lightly squeeze some epoxy out but not all.
Clean excess epoxy from outside of hull, and if used, remove masking tape. Clean any visible epoxy off the thread.
After 24 hours the nut can be tightened to no more than 15 ft.lb – there is no need to over tighten this nut as the fitting is now part of the hull.
Thread Sealant Methods:
Teflon tape
Teflon tape is a traditional method which provides a good seal when applied correctly, however in some cases if the position or tightness of the Ball Valve or Skin Fitting is incorrect, it has to be unscrewed and more tape applied, slowing the construction process. Additionally, the fitting can sometimes be turned by hand after being installed.

Marlon
Bedding compounds such as 3M’s #5200, Sikaflex
or Boatlife are to be recommended as well as others that are equally suitable.
 
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If you are only epoxing this one small component and don't need much then the epoxy that comes in a double syringe from DIY stores is fine. The powder they mention is silica, you mix it with the laminating resin to thicken it and turn it into a glue. make it thick enough and it also makes a good below the water line filler although it's hard to sand . You can also mix micro ballons with epoxy which makes a good above the water line filler which is easy to sand. I've also gone the trudesign way and fitted their seacocks. The through hulls are designed to be part of the hull and fully epoxied in. If they ever need replacing due to damage then you just grind it off as it's only plastic. I also fitted their load bearing collar too.
 
Funny, I could swear I remembered mine saying that Sikaflex can be used. Just dug through the documentation box, and voila, in 2015 the paper that came with my Trudesign bits said: "[..Epoxy..]. Sikaflex 291i or 3M 5200 Fast Cure can also be used."

So I used Sikaflex. Worked fine. I like to think that having a small amount of elasticity is good there. Hulls tend to flex a little.

Perhaps West System signed a sponsorship agreement ;-)
 
They seem to have changed the instructions as epoxy used to be the alternative fixing method to sealant. I used Sika 291i with Hawke White on the threads until I ran out so used Hermetite red on the last one.
 
They do seem to be a bit contradicting themselves as I have just downloaded their "Product Information" again and one version (version 3.2 which I think I got a couple of months ago) says use Epoxy and another (on their web site currently but no version number) says use epoxy or the other glue/fillers.
 
bobgarrett said:
They do seem to be a bit contradicting themselves as I have just downloaded their "Product Information" again and one version (version 3.2 which I think I got a couple of months ago) says use Epoxy and another (on their web site currently but no version number) says use epoxy or the other glue/fillers.
Click to expand...

Unfilled/not thickened epoxy is harder to use if surface not horizontal. OTOH, 291i just stays where you gun it, without running around or dripping.
 
for what it's worth, on my 9 below waterline thru hull Trudesign fittings I've used sika 291i
That was 3+ yrs ago, boat is in the water (except for 1 month out two yrs ago), no leaks nothing.
Wouldn't ever use epoxy for that, it's stupid.

cheers

V.
 
Tammany said:
If you are only epoxing this one small component and don't need much then the epoxy that comes in a double syringe from DIY stores is fine. The powder they mention is silica, you mix it with the laminating resin to thicken it and turn it into a glue. make it thick enough and it also makes a good below the water line filler although it's hard to sand . You can also mix micro ballons with epoxy which makes a good above the water line filler which is easy to sand. I've also gone the trudesign way and fitted their seacocks. The through hulls are designed to be part of the hull and fully epoxied in. If they ever need replacing due to damage then you just grind it off as it's only plastic. I also fitted their load bearing collar too.
Click to expand...

This is what I did. Boat hasn't sunk yet!
 
Yngmar said:
Funny, I could swear I remembered mine saying that Sikaflex can be used. Just dug through the documentation box, and voila, in 2015 the paper that came with my Trudesign bits said: "[..Epoxy..]. Sikaflex 291i or 3M 5200 Fast Cure can also be used."

So I used Sikaflex. Worked fine. I like to think that having a small amount of elasticity is good there. Hulls tend to flex a little.

Perhaps West System signed a sponsorship agreement ;-)
Click to expand...

Just used Sika 291i on one yesterday - as I've done with 8 others recently.
 
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