I won't nick that hose with this hole saw...

Bad thinking!  Everyone knows that any hole saw put aboard a boat becomes a "water seeking hole saw".

I was cutting a hole for a new hose, a nice simple diagonal hole through a locker floor and a bulkhead. I could see through another hole, the hose I needed to not nick. I knew I needed to control the feed pressure on the saw, and just barely finish the cut before stopping the saw.  Yet despite my best efforts to control the feed pressure on the saw, I failed miserably and touched the hose, yet ever so slightly, with the saw.  The bad news is that the hose was 1-1/2 inch diameter and open to below water-line (I wasn't going to nick it so I didn't shut the sea cock.  Bad Sean!)  The good news is I didn't cut it clear through, I only compromised about half of the wall thickness of the hose, so I only had to spend an extra couple hours changing one of the most difficult hoses in the boat.

We were changing the head (toilet to non-boating types).  We had a Raritan PHII, and while it worked, it was getting pretty odiferous flushing with sea water.  (Sea water, even in the intake hose will "rot" in short order and produce a sulfur odor akin to rotten eggs.) Not to mention what sea water does to the insides of the hoses (the calcium builds up very quickly).  So we decided to convert to a fresh water flush.  We have three fresh water tanks, and the smallest one is proximate to the head, so it was easy to plumb it as a dedicated tank for flushing.

We decided to go with a new Lavac marine toilet, a time tested and simple solution, and a favorite of many cruisers.  It has a bowl with a 1-1/2 inch outlet at the bottom that gets plumbed to a great big diaphragm pump.  The lid actually has a seal, so to flush you just close the lid and take some strokes on that pump, which empties the bowl and creates a vacuum in the bowl which is what draws the flush water in.  After about 30 seconds, the
vacuum breaks and you can lift the lid and everything is ready to go again.

You can read more about the Lavac here.

SK


--posted Wednesday, Jun 10, 2009