28TE thru hull

[alandry100]

I think I'm drilling tomorrow. I see in the schematic that the they recommend to drill larger, fill with thickened epoxy then drill the actual thru hull through the plug. If anyone has done this - how big should I make the hole for a 3/4" thru hull?

[Pitou]

I like a quarter inch extra on all sides .. 1 1/4" for a 3/4" thru hull. Glad to see that you're doing things correctly and protecting your hull.

Post a picture of the hole saw plug of the hull when you're done so that we can all see the coring. This will be helpful to have on the forum for the '04 vintage hulls.

[catalina_mike]

You can just use 5200 to stick it to the hull. Proper cleaning first and let it cure before mounting the pump or mount the pump first then stick it to the hull.

[alandry100]

I like a quarter inch extra on all sides .. 1 1/4" for a 3/4" thru hull. Glad to see that you're doing things correctly and protecting your hull.

Post a picture of the hole saw plug of the hull when you're done so that we can all see the coring. This will be helpful to have on the forum for the '04 vintage hulls.

I will definitely document the install. When I drill and fill I'll figure out the layout.

[GSSeattle]

I think I'm drilling tomorrow. I see in the schematic that the they recommend to drill larger, fill with thickened epoxy then drill the actual thru hull through the plug. If anyone has done this - how big should I make the hole for a 3/4" thru hull?

Just a thought here - when I drill for mounting something, I drill the correct size hole and then use a dremmel or similar to dig out the core material about 1/4" on all sides, but leave the top and bottom laminate. Then I fill with thickened epoxy, and re-drill before bedding it. I think this would be better than drilling an oversized hole because it retains the strength of the laminate, while sealing the core. Full disclosure, I have yet to drill for a thru-hull...

[RobS]

Further to Greg's approach: A properly sized allen key (hex wrench) chucked in a drill works great for digging out the core (long side in the drill)

[alandry100]

Finally got the nerve to drill a hole.

Thuhullhole.JPG

Balsa cored. I will post the plug but it was still in the hole saw and forgot to get it out and photograph.
Used the allen wrench method to chip back some of the core - pretty messy process. If you are type A I would go the Dremel route. Luckily I am not. Filled with silica thickened adhesive epoxy. Temps were around 45-50* so the Total Boat slow curing hardener that I had was not recommended. Trip to West Marine - went with G/flex thickened.
I also epoxied down the backing plate and a board for the washdown pump.

BackingPlate.JPG

Tomorrow plan to re-drill hole, fill any voids and mount the thru hull.

Any ideas on how to line up/ tighten both the clamshell and the seacock so they are both facing in the correct direction without making a ridiculous mess with 4200?

[catalina_mike]

Looks good.... 4200 is good so you can reseal on haulouts.

[Pitou]

You're on the right track and good job sealing the balsa core. All the talk and Albin promotion of going to AirX coring in 2002 and through personal experience and seeing others still having balsa I wonder if they ever really did it. My 2006 has a "dry" balsa core in the hull.

You'll find it much easier and doable having two people, one inside and one out, getting the scoop facing forward especially if your using a scoop strainer that is attached to a threaded nipple.

[RobS]

Are you sure that's not the closed cell foam coring material?

Here's a 2001 that I drilled and carved out for a ducer install. Definitely foam cored...

And the foam core transom gunnel on my 2000 when I drilled for adding a road holder. I had already gelcoated the bore when I took the rod holder pic but the plug is there.

[alandry100]

Rob -
Actually not sure at all - I’ll look again at the core when I get home. It could have been foam - was very easy to remove.
A

[alandry100]

64579520-F41E-4093-A704-EC739E136593.jpeg

Upon review - I think it’s foam.

[alandry100]

With measurement.

91A0E6F5-AB71-47E6-9376-1411E1A6375F.jpeg

[Pitou]

64579520-F41E-4093-A704-EC739E136593.jpegUpon review - I think it’s foam.

That is defiitely foam. Thanks for sharing.

As you move through this project, make sure that you are as diligent with the bolt or screw holes for the scoop strainer and you'll ensure a long dry installation.

[alandry100]

For the screws - what is the proper way? Over drill - fill with epoxy - then re-drill? Or can the holes be drilled then injected with 4200 and filled?