Tuesday, December 6, 2011

Sump Box for the Bilge

The people over at Carbo Rico_Tiburon36 have built a very nice sump box here's how they did it..........
I needed to add a separate sump to our grey water system. I have a store bought sump from Rule in the forward end of the bilge for the head and shower, but needed one to handle everything else including it. At a $100 bucks or more for one of these plastic boxes, I figured I could make one for a lot less.
Here is how I did it. You can build one too. It's fairly simple. I must add I had some scrap Plexiglas already. I bought the 500 gph bilge pump on ebay. The rest was scrap pieces of marine plywood.

Box measure 11x11x6 inches. It is 1/2 inch ply with 3/4 x 1 inch around the inside for a lip to help seal it and give a place to mount the bolts. The plastic screen inside is actually from a craft store. It is used for some kind of needle work.

Build the box. Then give it several coats of thinned epoxy inside and out. Save money, Don't buy CPES epoxy, just cut your already mixed epoxy with some MEK (NOT MEKP), thin till it's just a little thicker than water, almost half and half mix. MEK is just like Acetone, but evaporates much slower. Let it cure between coats, but put the first 2 coats on while still green. Sand for the last coat and thin it only a little or maybe not at all. You'll know you have enough coats when it is very shiny when finished.

Side note; this little trick will help you fix rotted post and the like without buying special epoxy. I actually apply it to porch post and columns before installing them. Then they never rot.

I used 1/4 inch bolts for the lid. Insert them as you make the box.

From Sump

Fit Plexiglas lid.

From Sump

Install pump and float switch.

From Sump

Install all the fittings in the box and screen plus the fuse holder outside.

From Sump

From Sump

Then install it. I eliminated 12 thru hulls with these two sumps. Now I only have 3 thru hulls.
I mounted it to the bilge with some stainless brackets I had. Screw them to the side of the box, make some pads that can be epoxied to the bilge , with bolts so that the whole thing is removable.
It is under the engine, but hopefully it will be somewhat accessible.

Heat Exchanger Modification

After installing a new heat exchanger for our Gen Set, we had no further issues. However, the primary issue of "stuff growing inside our heat exchanger" has not been resolved, and, because the Fischer Panda generator has it's heat exchanger in such an awkward place to service, we decided to modify our new heat exchanger so that it can be cleaned out with the minimal of fuss annually.
  We took our heat exchanger and removed the ends by "unsoldering", so that new ends could be attached that would allow for easy removal.
We attached some brass ends (by soldering) with a reducing thread and then used a threaded cap, and finally a threaded tail to give us our 19mm hose fitting.

In the picture to the right, you can see how easily it is now to remove the end caps to clean the internals of the heat exchanger. And with it's new mounted location, we should no longer have issues with our Gen Set shutting down to over heating.
Since we have been dealing with heat exchangers, we have learnt something. Heat exchangers made from copper and nickel last a lot longer than those just made from copper. All heat exchangers should have some provision for cleaning the "internals". A sacrificial anode is a must. A fresh water flush through the engine and heat exchanger before turning the engine off for prolonged periods, increases the life of the engine and heat exchanger.

Monday, December 5, 2011

Stove Top Plates, Force Ten Stove

And so it goes that not everything one does on a boat always works out the way you would like them to. You may browse an older post where I took our stove top plates that had seen some years of use and started showing signs of rust as the paint wore/burnt off, were refurbished with a coat of high temperature paint. This lasted all of about three months, before the new paint also was "decayed" and rust started to reappear. I could have continuously repainted them, but instead opted for this solution. Hopefully this will work for a longer period of time.

I took the stove tops and took all the paint off with an angle grinder (carefully), and then worked the surfaces back with finer sandpaper, to finally using a scotch brite wheel and then polishing the steel. These were then sent off to be chromed. The underside was just cleaned from the old paint and not finished as well as the top surfaces. You can see the under side of one at the top of the photo.
I know the chrome will discolor with the heat, but should not burn off. Hopefully these will keep rust free and my wife will find cleaning the stove a little easier.
Cost $20 and a little of my time in the workshop. I'll give a report after the next cruising season as to it's effectiveness.