Move House Bank 1

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December 2003 - This is another little project that's been on my list since I bought the boat. In fact, the view to the left has been carefully omitted from every picture I've ever taken.

Inside that box are two 6V Golf Cart batteries.
They're smack dab in the center of the aft cabin!
Now, this was a good installation in the sense that the box was well constructed, all the weight is on the centerline, and the box is bolted to the bulkhead with a strong steel strap.

But come on --right in the middle of the sole?
I bash my shins on this box every time I'm on the boat!

It's made from wood, then will be soaked in penetrating epoxy, and covered with fiberglass.

I dragged the bench belt sander down to the boat for this job, because there are so many weird angles required to make it fit snugly.

This isn't the design I'd started out with. Originally I was going to put four lateral 'stringers' of 3/4" plywood under it, but after making the first one I realized
that would take too long. So it's braced on all four sides, with a 'foot' that goes down to the one flat area in the bottom of the compartment.

I'm going to move it inside the port quarterberth. It will move the weight about two feet to port, which is not good since everything heavy on this boat is on the port side. (Arggh)

I'll just have to put another two batteries over to starboard.

To move the box I'll need to build a stable flat platform. (That's why I've put this off so long.)

This piece of 3/8" marine ply is 1.5" bigger than the existing box.

In addition to making it stable, I need to think about venting the box outside the compartment.

The bench belt sander was critical for getting the braces to fit well.

I knew they were correct when they fit in place and didn't want to move, even before the screws were in.

I don't want this thing to break and come loose!

I was pretty sure that the 3/4" plywood
I found in the garage was Marine Grade,
but I see voids in the edges that shouldn't be there.

I'll fill those with epoxy putty before covering with fabric.

This little gadget really helped
to get the angles right.

Here it is,
framed and rock solid.

The liner under the 'foot' is braced directly against the hull with putty, so this is structurally sound.

Now to take it home, disassemble it and make it rot-proof before
glassing it
into the boat.

The one side that doesn't have a brace attached to the shelf will be braced with this piece of plywood that's attached to the forward bulkhead.

It will be soaked in penetrating epoxy,
and epoxied directly to the bulkhead

It soaked up about a pint of Smith's Penetrating Epoxy.

Before assembly, I packed all the voids in the plywood with epoxy. Then the whole thing was glued together with super thick epoxy, and the underside covered with fiberglass tape.

I changed the wood 'foot plate' to fiberglass.
It was a scrap left over after cutting a hole for some other project.

It's 3/8" prefab from McMaster-Carr.
This won't get wet and rot.

Abrupt change of plans!

I'd planned on modifying the old box to fit,
but then remembered that I had
a new Blue Seas battery box
in the back of the garage.
(Go ahead and laugh, I did.
Even I don't know what's in my garage anymore.)

It will fit. It's also much lighter than the old
wood and fiberglass box.

The box has good attachment points
for lag bolts, but since I hadn't planned on using it I hadn't built that kind of
strength into the design.

Fortunately, two of the bolts fit nicely right down into the plywood sides.

The other two just penetrate the plywood, and so my design required a little

I epoxied little scraps of teak
in place for the
bolts to bite into.

That's pretty solid.

In the winter, epoxy doesn't kick fast, so there's time to work it.
That's nice.

I made a super thick putty of West System and colloidal silica, to cement the shelf into place.

This is clearly
a permanent installation.

Down at the boat, I taped off the area,
then took a grinder to the edges where the shelf will sit.
This roughed up the area for a good physical bond.

At the very bottom, I drilled a 1/2" hole for water to drain out of the compartment. When I'm done, this area should be a sealed compartment, but it's a safe bet that somehow water will get into this place eventually. If there's no drain it'll get stagnant and stinky, right under the double quarterberth.

Note that I also took the grinder to the bulkhead where I'm going to epoxy the forward brace. I cleaned through the veneer into the laminate, so the epoxy will get a good bond.

Fifty pairs of latex gloves later..

All four sides are firmly seated
in a thick goosh of epoxy putty.

The forward (right) side is epoxied to the transverse structural bulkhead, and glassed into place.

The other three sides are epoxied to the boat, with thick fillets of epoxy putty supporting them, and two layers of fiberglass rolled on with a slotted roller, inside and out.

This platform will never come loose.

The battery box will block access to the forward edge of the compartment, so I put a Beckson port there to maintain access.

I don't know if this will be big enough. We'll see.


A word to the wise
when sawing through existing bulkheads.
Keep an eye
on the other side!

Fortunately, the box is right next to where it used to be, so I don't have to change the cables. They fit fine.
That saved a lot of work!

I forgot to pick up little 'boots' to cover the terminals, so they're wrapped with tape.
The USCG auxiliary inspectors say this must be done.. although ABYC regs say that it isn't required if batteries are in a box.

The box is actually about 20 pounds lighter than the old wood and fiberglass box, so perhaps that will help offset the
weight shift to port.

After sanding and a coat of paint, it looks a bit nicer.

Although no one's ever going to see it again..

I packed the Lag Bolt holes with thick epoxy putty, so that any little cracks would be filled and the grip on
the bolts will be strong.
However, I don't want to actually epoxy the bolts in
(the box may need to be pulled on occasion to get better access to this locker)
so I covered them in some good grease.

Detail on the fastener.

This will need some serious cleanup.
The sole where the box sat appears to have sustained some water damage.
I think I'll add some vented teak doors to remove the scars in the bulkhead,
as well as vent the batteries.

We'll see about the sole. I might just cover this whole section with interior treadmaster or something, but not until I'm all done with interior projects.
(I've dinged up the new main cabin sole pretty well with all the construction in the last couple of years.)

It's such a joy to be able to stand here. This doubled the floor space in the aft cabin, and accessing the engine and port quarterberth will be a lot less painful.