The house bank battery box, bolted to the battery box shelf |
You'll recall that I had long before this time decided I would orient that house battery bank box in the fashion pictured below.
You'll also recall that I had constructed cleats of Douglas fir for the house battery bank shelf. These I would soon glass to the hull as a foundation of sorts for the battery box shelf.
You also may recall that I had taken into account the future location of the cleats when deciding where exactly to mount the Noco brand battery box on the shelf.
The forward end of the box would be easily accessible, since it would be close to the cutout under the companionway. For this reason, I planned to use 1/4 inch stainless steel hex-head bolts to secure the box. With a wrench I would hold the hex head steady underneath the shelf, while I tightened the lock nut down with a ratchet wrench on top of the shelf.
The aft end of the box was going to present some problems. Fortunately, since the cleats were not as long as the shelf itself, they would not prevent the installation of hardware through the mounting holes. The problem was that it would be impossible for me to use both hands to install hex head bolts and lock nuts on this end of the shelf. There was no way that I could get both of my hands back there to do this work.
At first, I considered installing weld studs. I had used these earlier for mounting the panel over the cutout underneath the companionway. It just so happened, however, that when the time came to permanently install the shelf I no longer had any more 1/4 weld studs on hand. I was on a roll, and I did not want to wait several days for this hardware to arrive in the mail at my home in Charleston, South Carolina from McMaster-Carr in Atlanta, Georgia.
Therefore, I took a trip to a local hardware store (not a big box retailer) and described to the friendly folks there my predicament. Unlike the big box retailers, which are staffed with people who know almost nothing about the products they sell, these people actually know what they're talking about. They quickly pointed me to their supply of T-nuts. Since this store is in a coastal area, it had stainless steel versions of these T-nuts in stock. As I would later discover, McMaster-Carr sells a similar product, but calls it a "weld nut." These particular T-nuts that I purchased from this hardware store had holes on either side of the flange - holes that were made for securing the nut to the material (as I shall explain below).
Although the T-nut might look quite small in the picture above, it was actually large enough to accommodate a 1/4 inch bolt.
Earlier I had drilled 1/4 inch holes in the battery box shelf, since I planned to install 1/4 inch bolts or studs in all four holes. Now that I would be using the 1/4 inch T-nuts I needed to enlarge the two aft holes. The external dimensions of the T-nuts were of course greater than 1/4 inch.
Into the enlarged holes I inserted the T-nuts. Then I drilled pilot holes so that I could secure the nuts to the underside of the shelf with stainless steel pan head wood screws.
Afterwards, I temporarily installed the battery box shelf, just to see how the T-nuts worked.
As you can see, they did exactly what they were supposed to do.
As I mentioned at the end of my last posting, I pre-painted the underside of the battery box shelf. After I had accomplished this, I re-installed the T-nuts and prepared to glass the shelf permanently into place.
Earlier I had also considered how I might best secure the reserve battery bank on the port side shelf. Of course, in accordance with the regulations, I would use a strap.
I did, though, want something there in addition to the strap to keep the box absolutely still. My solution was to construct a frame of sorts for the battery box.
I constructed this frame out of scrap pieces of mahogany.
I had to leave one end open to accommodate the curvature of the hull.
I thought about leaving the mahogany plain, but eventually decided to stain it and varnish it along with other pieces from other projects. I began by wetting down the wood in order to raise the grain.
Then I rubbed Pettit brand Brown Mahogany stain into the wood with a clean rag.
The stain brought out the deep, rich color of the wood.
After I had rubbed away the excess stain and allowed the wood to dry for one day, I came back with Epiphanes varnish. The first coat, as per the manufacturer's recommendations, I thinned by fifty percent.
This enabled the varnish to creep deeply into the grain of the wood and seal it.
Two days later, I lightly sanded the wood with 220 grit paper. This would remove tiny imperfections and provide some tooth for the next coat of varnish.
I continued this varnishing-and-sanding ritual for quite some time. On these pieces of the battery box frame I stopped at three coats (on each side). If these pieces were going to be exposed to the elements, I would have applied eight to ten coats as I did for some of the other pieces.
Before I had ever done any of the varnish work I had pre-drilled the pieces, and I had pre-drilled the shelf on which I would mount the frame, as I described in an earlier posting.
At this point, it was simply a matter of screwing the mahogany pieces into place.
This ends this posting on the hardware and the techniques I used to secure the battery boxes in the lazarette of Oystercatcher, my Ericson 25.
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