Saturday, January 30, 2010

Sea Chest- Final Resting Spot

OK, I'm getting kind of tired of the re-work, but I had to move my sea chest location once again. I had abandoned the first location as the intake was to small, increased the size of the intake and moved the sea chest to the area in front of the generator. After doing some assembly, I realized that the sea chest was going to be to close to the water line, and I want it a below the water line. I also felt that having it in front of the generator was going to be a pain in the ass, and I'm sure I'd be regretting it years down the road as I banged into it while servicing the generator. So, as much as it pained me, I moved the sea chest again. I turned it 90 degrees, and moved it another foot away from the generator.

During my recent visits to the scrap yards ( selling scrap metal), I've been scrounging around for some for some 2" 316 stainless. No luck on finding some, so I had to break down and make a small purchase of some new material. Making sure all my parts were 316L was important to me so having to buy new material was not such a bad thing given I could assure quality.

The first line of business on the sea chest was building the manifold. I used a 12" piece of 2" along with two 1" x 4" nipples. I cut the nipples in half on my lathe so I ended up with the four pieces needed for my valves. Using a hole saw, I bored four holes in the 2"x12" nipple so I would be able to weld in the valve stubs. I was going to use a boring head to make the bores, but the hole saw did just fine by using the micro feed on my mill and running water on the bit to keep it cool.

Welding the 1" nipples in the manifold was pretty easy. I stood the 1" stubs on the work bench then lowered the 2" manifold on to the stubs and held the manifold up with blocks. This way I was able to keep the stubs plumb, level, and square with the manifold without having to come up with a clamping contraption. I tacked the stubs in place, then placed the manifold in the vice and welded her up. I made two passes around the each stub. I air tested the manifold to 40 psi and I'll be damned if it passed on the first try.

I bolted the stainless flange to the flange I welded into the hull, and just for kicks I tested to see if they were electrically isolated. The electric isolation test was good.

I've yet to find a used 2" sea strainer, so I'm unable to finalize the assembly. I'm going to need to brace the manifold both vertically and horizontally, but I can't make the brace until I know the final location of the end after the sea strainer is in place. I also think I can lower the manifold 2" by using a close nipple vs the 4" nipple I have between the ball valve and the "T". I'm going to keep my eyes open for another valve that with an overall length of 4" vs the 6" valves I have now. I really can't finalize any of this until I I have a sea strainer.

I'm very happy with how the sea chest looks, and more happy with it's location. This set up will be extremely easy to service and bring various water intakes on or off line as I need them. I went with a "T" vs a 90 on building the sea chest in case I had to blow a clog out of the intake while under way. I can screw a nipple down in to the "T" to get above the water line, and clear any thing away without having to get into the water. If I had used a 90, cleaning from the inside would be difficult at best.

Friday, January 22, 2010

Scrap yard finds for the engine room

My excavating business is as poor as I've ever seen having been self employed for 20+ years. With my revenue down so low and my not wanting to not work on the boat even though I have much less cash to throw at the project, I've taken to visiting scrap yards looking for some material.

This post still reflects my working in the engine room, but I want to look at the value of utilizing used material.

Given the down turn in the economy, I had my mind set that I was going to have to sheath the engine room floor in plywood and probably paint it. While down at the scrap yard today unloading the fruits of me cleaning up around the shop, I noticed some aluminum diamond plate getting ready to be processed. The material was a double diamond plate pattern 3.5' x 7.5' x 1/4" thickness. There were 20 sheets, but from what I could remember five sheets would be plenty, so I went ahead and struck a deal for six sheets. We agreed on a price of $.80 per pound. For the six sheets my total costs were $300.00. The pattern of the diamond plate was nothing I'd ever seen before, and as you can see from this picture, it is a double diamond pattern. From here on out, I'm going to call it "Double D", or "DD". Personally, I am partial to "DD", and it just makes me happy thinking about it.

I also needed a 2" stainless ball valve for my sea chest, and a 1.5" stainless ball valve for my holding tank pump out station. This scrap yard had a large bin of stainless valves and it only took me a couple of minutes to find two I thought looked good. I paid $1.00 per pound for the valves so my total cost for the valves came to $18.00. Both valves were 316 grade.

Once back at the shop I took the valves apart, applied some lithium grease, re-assembled them, then air tested them to 40 psi. I only used 40 psi since I was using PVC for my air test, and in all honesty, the valves will see no more than a two or three psi of pressure.

I also made a call to my local metal supplier to see what the costs were on new 1/4" diamond plate aluminum sheets. I was quoted a price of $3.75 per pound. The sheets of diamond plate I purchased weighed around 375 lbs. With the new cost of $3.75 I figured I got $1400.00 worth of diamond plate for $300.00. I'm also going to estimate the value of the valves @ $175.00 and $150.00 respectively, for a total valve value of $325.00. By purchasing used material, I think I can figure the new value of the material at about $1700.00, but my total outlay for this material was only $318.00. Quite a nice savings in my opinion. I should also say that the scrap yard paid me $249.00 for the 2700 lbs of scrap I dropped off.

One more thing I should add about the valves is that they are rated at 1000 psi, and I think they are sch. 80 or sch. 120. I can say with confidence that these valves are what I would call "beefy" valves, and have what I would guess double the duty rating as any valve one might buy from a marine catalog.

The aluminum diamond plate I purchased was obviously used as a cat walk or some other industrial application. This is a great example of why metal is such a good building material. While this material could have been in heavy service for 20+ years, a little work on my part and it will clean up and look just like new. I also think that the aluminum diamond plate will make my engine room floor as fine as any of the so called high end production plastic yachts on the market.

Sunday, January 17, 2010

Thru Hull Fitting

I decided to make each job I have to do in the engine room it's own post vs adding to the "back to work on the boat" post.

Now that I'm back working in the engine room I find myself wondering "why in the hell did I do that"? Maybe it's an older and wiser thing or maybe I just wasn't thinking right a couple of years ago, but either way I find myself having to do a bit of re-work.

My main engine is keel cooled with dry exhaust. My generator is cooled through a heat exchanger with wet exhaust. I had originally laid out the generator to be installed on the port side, but with all the weight I was putting to port, I thought it better that I move the gen-set over to starboard. Looking at the through hull fitting I had originally installed to service the gen-set ( a 1" pipe welded into the hull and threaded on its end), I began to feel this set up was totally inadequate for my future needs. Having realized just how lame my original thru hull was, the first order of business in the engine room was to remove the that 1" pipe and fabricate a more suitable through hull.

I don't want to punch a bunch of holes in my hull so I decided to fabricate a two inch sea chest that will handle my water intake needs. I want to have a fore and aft wash down set up, I might also want to have the option of raw water flushing the heads if fresh water gets scarce, I also need to think about possibly cooling my hydraulic system, and I need to be able to cool my generator.

I decided to install one 2" water intake using socket weld flanges that will lead to a proper valve, then through a sea strainer to a manifold consisting of four or five 1" valves to direct water as I need.

I bought the socket weld flanges from my local plumbing supply house and used sch. 80 pipe for the thru hull fitting. Because I want to use stainless steel for my valving and manifold, I had to electrically isolate the thru hull from the stainless. I did this with a gasket and isolating bushings for the flange. The flange on the hull side is carbon steel, while the flange on the boat side is stainless steel. In the first picture, you can see the green coating on the carbon steel flange that is welded to the mild steel sch. 80 pipe.

After welding the thru hull pipe to the flange, I gave the piece a quick sand blasting before I welded it in place.

These pictures show the various parts along with the flange welded into the hull. On the last picture you can see the remnants of red dye I used to test the welds. Air testing this piece would have been difficult and while the welds looked good I decided to dye test just in case. I'm planning on making a trip to the scrap yard later this week to see if I can find some valves and some piping. In the past I've been able to buy stainless steel ball valves at the scrap yard for $10.00, and with a little luck I'll also find some couplers and other bits I'll need.

Thursday, January 7, 2010

Back to work on the boat

It's been a while since I've made a post but I'm happy to say that I'm back to working on the boat. Life seems to get in the way of things we want to do, and I've recently had a run in with just such an episode. Getting the house ready for winter, a short lived uptick in my business ( business is still way down and dropping), pulling the Caver boat out of the water and winterizing, cutting firewood for the shop and house, blah, blah, blah. I"ll quit bitching now, but I'm sure all who might read this will be able to relate.

The next job at hand on Conall's big boat build is to finish getting ready for the insulator to do his thing. I need to finish painting the engine room witch is turning into quite a bit of unfinished business. My list of what needs to be done in the engine room is as follows:

- Install the generator and weld in all the fittings for the water lift exhaust system.
- Weld close the generator access hole.
- Install ac and dc electric conduits and various junction boxes and fixture boxes.
- Install the center baffle on the exhaust/intake trunk
- Re-prime the engine room with etching primer, then top coat with Alkyd Enamel
- Install all the wood firing.

This is the abbreviated version of my list as I still have ac and dc conduit work to do in the master stateroom, forward cabin, and head. All in all I would have to guess that I'll have a solid month worth of work to get her to the point of being ready to insulate.

I"ll start to post some pictures as I move forward. I've found that this boat building thing seems to go a little easier if I break the "big boat build" down into about 80,000 smaller jobs that make up the "big boat build". I might continue this post and add to it as I mover forward, or I'll post a separate entry for each of the micro jobs I get finished.