Monday, January 30, 2012

Aft Bulkhead

Finally I have made a start on the glass. I used a wire brush on my drill and went over the rear bulkhead and adjoining areas both fore and aft. Then I went over the area with a palm sander with 40 grit sandpaper to leave a rough surface for the resin to stick to. Then, because I had removed the lower portion of plywood on the aft side due to rot with a wood chisel, I had punctured some holes in the firberglass on the fore side. Before I rebuild the "core" of the bulkhead, I needed to place a new skin on the fore side. So I cut out a piece of 1.5 oz Matt to fit and, with some 105 West Marine System resin (205 hardner), I wetted the Matt in place. First time for me using West System. It worked perfectly. So, now that I have the front layer of glass in place and cured, I am about to use fiberglass pipe wrap insulation wetted down with West System to fill in the missing plywood on the aft side. To do this I have made a cardboard template covered with packing tape to press over the wetted insulation to keep it in place (on the verticle) while it cures. I will then remove the cardboard template and run a final layer of Matt over the entire back side of the bulkhead covering the upper portion of plywood and the lower section of resined insulation. Eventually this will all be painted.

Sunday, January 22, 2012

To Keel Step, To Seat Step or To Deck Step the Mast

When I bought this boat, I thought of just getting back on the water with the wind over my shoulder and the exhilaration of the bow dipping, the stern raising a bit and the feeling of "taking off". Then as I read more about Dinghy Cruising I began to see this as the perfect "Creek (slough or bayou) Crawler. Shallow draft, 2 retractable bilge keels and all open cockpit for tent camping on the water.............I could and still imagine being out there watching wildlife and leaving not a trace when I left. As I contemplated the "camping" aspect, I wanted to make available all the storage space I could. This was being hindered by the basic keel stepped mast design as it obstructed the 3 foot of bow space to any sort of real storage like a cooler. A duffel with clothes and a duffel with ropes, extra sails and maybe anchors were all that I could envision there and they would be somewhat "inconvenient" to access. So............I started thinking of extending the deck by 2 feet and deck stepping the mast to gain access to the bow space. I knew I would have to accommodate the compression of the mast (a compression post would defeat the purpose so I figured a strong bulkhead just under the mast would work just fine). I would cut the existing interior and replace with deck & bulkhead, all of oak plank and West Marine Epoxy covered glass cloth. The deck would only be 2' long, 4' wide and the bulk head would be only 2 ' high. I didn't see a problem with flexing in the 1/2" x 1' oak planks.

Saw line: 


Proposed Deck & Bulkhead:



After waking up a few times in the middle of the night trying to imagine how all this was going to work, I decided that deck stepping the mast was just too ambitious for me right now. But I still wanted to get the mast up off the keel so, 1) I would not have the initial problem that rotted out the entire floor to begin with and 2) so I didn't have to derig the shrouds and lift the mast out of the hole in the front seat every time I wanted to lower the mast (as in maybe going under a low bridge in my future intended creek crawls). So I settled for seat stepping the mast and that is my now intended build. I figured that I can always deck step at a later date if it proves to be necessary. So I bought 8 foot of 1/2" x 7 1/2" Red Oak planking. I will use that to lay flat on the new floor, laminate 4 together to make the compression post and another piece to lay flat on top of the post (and front seat) to support a tabernacle for the mast foot. This I believe is within my skill to build properly and will suffice as I will likely only be day sailing for a year or more on my local Arizona lakes. Even an overnight-er will be fine only an hour's drive from home.



And then.............While I was at Home Depot to get the planking for the mast step, I started thinking about the new floor and my intent to build it out of glass exclusively on a cardboard template and place it in the boat on top of the existing foam without the "benefit" of plywood. So I thought I had better seek some advice. I called my buddy Jorge in Mobile, Alabama (who incidentally was also in Home Depot!!!) as he is a contractor, sailor and restorer of old sailboats. He said I either needed to use plywood or more layers of fiberglass cloth/matt than I could imagine. So the next question was Marine ply or not. He said as long as I was going to epoxy the plywood anyway (floor = 2' x 12') I need not worry about marine ply. "Just get a top grade ply, epoxy it, lay it in with a glass/cloth overlay and get back on the water!" I think that was the way he put it. "After all", he said, "this is a daysailer, not a blue water boat, right? and besides, it will last longer than you will be to sail it." So I bought a top grade sheet of 3/8" Oak plywood and am planning on getting to the floor in the next few weeks. It is in the low 70s here now and very nice to be outside working on the boat. I have a bit more prep to do and then I can start with the construction.  Will keep in touch.

Monday, January 9, 2012

I have been reading DYI articles, blogs, & forums, watching You Tube tutorials and talking to anyone that I think knows anything about fiberglass and it’s marine applications for the last 6 months. I think I have finally formed a reasonably versed opinion on the various materials and their applications.

There are 2 major types of fiberglass resins and 2 major types of fiberglass core materials.
Of the 2 resins, Polyester resin is the cheaper and is used for primary adhesion. Epoxy resin is much more expensive and is used for secondary adhesion. I will get to Cloth & Matt in a moment.

By primary adhesion I mean an application like the making of a boat hull.
Polyester works well for this application, especially when used wet on wet. Wet on wet is when a layer of cloth is laid down and subsequent layers are laid down while the previous layer is still wet with resin (or uncured). This is purported to make a very strong bond if the various layers can cure together.

By secondary adhesion I refer to fixing something to the cured primary adhesion like an addition to an existing hull.

Cloth is a woven material just as it’s description suggests and is primarily used for the construction of structure but can be used for just about any application. Matt is a pressing of fibers and can be used for filler or bulking up a construction project.

I am in the process of rebuilding the floor in my 16’ sailboat and after having removed the rotted plywood, I want to build a floor entirely out of fiberglass with no wood in the structure.
under the plywood was expanded foam and it is still in pretty good condition. It does have a few dings and depressions in it so I have decided to use the canned foam from a hardware store that is used for filling cracks in houses. This foam is "Closed Cell" foam and should be fine. It purports to be sand able and paintable so I believe that after filling, trimming with an electric kitchen carving knife (I am hoping to buy one used for $10 today) and sanding, the foam should be ready to accept a fiberglass floor with no other support. The floor is approximately 2’3” x 10’.

So I am intending to lay down 4 layers (Cloth/Matt/Cloth/Matt) in succession using polyester resin. When cured, I intend to lay one more layer of Cloth with Epoxy resin, sealing up the sides to the seat bulkheads. This should give me the cheapest and the strongest structure.

I bought the Cloth, Matt, and Resins this last weekend. Cloth & Matt was about $6 average per yard (48” wide). The Polyester Resin was $36 a gallon including hardener and the Epoxy Resin (West Marine System) was $150 per gallon including hardener. So you can see that the correct resin for the correct application is important both from a strength and cost perspective.

That is the plan I am going forward with and here are cross sections of my plan.


Monday, January 2, 2012

The Floor

Due to the split in the Starboard forward hull and the Deck/Hull join separation on the Port side, not to mention the normal splash from waves coming over the sides, water got under the floor at the mast step just under the front seat. This was let go for a good 30 years. I didn't like the mast keel stepped anyway so I pulled the mast foot and surrounding bracket/guide. What a mess! The entire boat floor was glassed over so I figured I would cut the glass to inspect the floor and just re-glass. I went to Home Depot to buy a small (3") saw blade to put in my drill like a grinder disc. I was told that tool doesn't exist and that it would be really unsafe to have a rotating open saw blade so it was illegal to even sell such a rig. It was suggested that what I needed was a "Multi Tool". The cutting tool is a back & forth vibrating tool (not rotating). So I bought the Ridgid brand "starter Kit" (the plug in not the battery model) that came with the power tool and the cutting head. It also has jig saw, drill, impact hammer, & ratchet attachments that can be bought. There is a life time warranty with registration. So, $130 later, I was headed home. It being the New Year's weekend, I had Friday afternoon, Saturday, Sunday & Monday off. The days are 75 plus degrees now so I got out to the boat on Saturday and started with the floor under the bow. Once I got the glass up, I found the the floor construction to be of unsealed 1/8" plywood over foam. This turned out to be the floor construction throughout the boat. There were two stringers, one each side of the cockpit. Both stringers ran from the aft bulkhead all the way under the forward bulkhead to the bow. These stringers were a strip of 3/8" plywood on top of foam. Both were completely rotted. So I ended up pulling the entire floor out except for the foam. The foam was fine as, although it was also wet, it doesn't rot so that part of the floor is still in tact and will be fine once it drys out. Under the mast step and under the main sheet block was a square of 3/8" plywood also unsealed and rotted. I pulled out the stringer on the port side. Still have to do the starboard side. Not sure how I am going to replace the floor but I know I don't want any wood in it so maybe "Sea Cast" for the stringers. I am also thinking of 3 layers of Glass. Well, since I still have the Starboard stringer to remove, I have time to think about it.