Ok to epoxy parts to fiberglass hull?

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Todd
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Sailboat: MacGregor 26M
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Ok to epoxy parts to fiberglass hull?

Post by Todd » Sun May 24, 2020 4:15 pm

I have a battery charger on the way. I want to make one of my bins under the seat as an Electronics / Power Center since I already have a charge relay and battery switch in there. Previous owner had to cut holes to mount the wood which has some of those parts mounted to it. I don't want to continue to put unnecessary holes because it leads to bolt heads on the other side that are exposed do the occupants.

When I did my bilge pump I used a cutting board and I just put a thin stripe of epoxy on each end and adhered it to the hull.

Is it okay to use that method too glue a cutting board to the hull? I found thick cutting boards at Walmart that worked well for the other project and was going to do the same thing. I was going to note the thickness of the board with a black Sharpie for future reference so I don't inadvertently drill through the board and into the hull when mounting a part. I suppose I could also do a raised strip on each side so there is an air gap behind it which would also help with that prevention.

My main question though is just is it okay to use epoxy in that application. I would Mount the battery charger to the board then Mount the board in an appropriate location with the charger screws still accessible in case it needs to be removed and or serviced.
Todd
'07 26M

:macm:

Banner_IV
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Sailboat: MacGregor 26X
Location: Head of the Bay (Chesapeake)

Re: Ok to epoxy parts to fiberglass hull?

Post by Banner_IV » Sun May 24, 2020 9:14 pm

Sure is, that is the standard practice using thickened epoxy and or tabbing with strips of fiberglass. The two things I will mention is I do not know how well epoxy will adhere to the cutting board material, and you should probably scuff up the fiberglass hull with some sandpaper for better adhesion.
BTW if you do not have silica for thickening the epoxy, talc/baby powder can be used in a pinch.

If you are interested in learning more, I would suggest youtube channels

Boatworks today and saillife for lots of fiberglass "O glorious sanding"

And west systems epoxy has several good manuals for free to download from there website
https://www.westsystem.com/instruction-2/
:macx: Shenanigans
Head of the Bay(Chesapeake)

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Russ
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Re: Ok to epoxy parts to fiberglass hull?

Post by Russ » Mon May 25, 2020 5:57 am

Sounds like a good plan.

For mounting my washdown pump, I used silicone caulk to "glue" a board of wood to the fiberglass. Then mounted the pump to the board.
As mentioned above, rough up glass for better adhession.

An extra benefit was the caulk absorbed vibration and if I want, I can use a knife to remove it.
--Russ

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Todd
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Sailboat: MacGregor 26M
Location: New Mexico

Re: Ok to epoxy parts to fiberglass hull?

Post by Todd » Mon May 25, 2020 3:59 pm

Russ wrote:
Mon May 25, 2020 5:57 am
Sounds like a good plan.
An extra benefit was the caulk absorbed vibration and if I want, I can use a knife to remove it.
That is a good point. I might do that instead. It will be in an Inspectable location so to reduce the permanency slightly would probably be a good thing if I ever wanted to switch it up.
Todd
'07 26M

:macm:

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