Re: 16' Nescher ski boat complete restore
Re: 16' Nescher ski boat complete restore
The next stage was to get the floor actually in permanently. Part of that process was foaming the floor.....now it seems this is a hot button topic with some people.....but after doing some research I decided to go with the pour foam. I still had a lot of reservations about the expanding foam. I popped some aluminum trim off a building once with the spray foam...I was surprised at how much force it produced. My friend David K used expanding foam on his....I wish I had some video! He used the tank type system rather than the pour foam. His method was to spray the cavity with what he thought would fill it, then throw the deck on top of it....then stand on it!
One of the reason I went with the pour foam, is I figured I could calculate how much I needed. All of the literature I saw indicated some type of volume ratio...."1 quart of mixed material makes 1 cubic foot of foam." I figured this way I have a good shot at getting the right amount of foam. I was still leery of "blowing up" my boat with it! I thought if it had a way to "escape" the cavity I would be ok. One of the web sites I found, Areomarine products in San Diego, had something along the lines of "have questions, call the owner answers the phone". I like that kind of service, so I gave him a call about my concerns. I told him that I was planning on tilting the boat forward, then starting in the bow and working back. I was planning on installing a 4' long section of deck, foam it, then repeat till I got to the stern. He said that would work great as long at the deck was fastened in place and the excess foam had a place to escape. So I bought my foam and was ready to go! Next was getting the deck in place.....
The front part of the original floor was just glass and mat. It was in the storage area up under the bow...about a 3' triangle. So for the first foam pour I made a "form" to shape the top of the foam. I also installed the first section of deck. I could screw it to the seacast keel beam, but had no way of attaching the edges. It looked like they had "glued" the original plywood down with resin, so I did the same. I used West Systems 6-ten...worked great. I was still worried about the foam bowing up my deck, so I put temp braces on each end of it. You can see the braces and the form in this pic..
I had a piece of wood to wedge between the bow support beam and the form to hold I in place...here is a picture of the form after I finished the foam. the two holes were "relief" holes at the front of the bow.
I learned a couple of things from my first pour....
1. The mixed foam is very "water like", I thought it would be thicker...therefore it "runs" like water.
2. It has to be "contained" to overcome gravity.
3. I worried too much about the expansion damage issues.
4. It doesn't expand quite as much as advertised.
Here is a picture of what happened...still had some work to do on my method!
I had the boat slightly tilted forward...unfortunately where I poured in the foam, the hull was curving towards the stern. The foam ran down this curve, gaining speed and ran completely past the deck! it ran back under the decking, but some it still expanded where I didn't want it to! Also the foam would only expand up so far before gravity made it grow sideways....The two board are some that I used for makeshift dams....So after pondering my next pour for a while this is what I came up with....packing tape, cardboard and duct tape!
Actually this is a picture from the 2nd section of deck, but you get the idea. The "dam" forced the foam to expand inside the cavity till it was full (also kept it from running out). Here are the results:
Once I removed the "dam", I just had to clean things up, and move on to the next section. I poured the foam into the cavity through 1" holes using a funnel. Once I had poured it in, I put a piece of duct tape on the hole and set a concrete block on it.
Hopefully this will save someone else the learning curve!
