1971 170 Aquasport rebuild

Discussion in 'Boatbuilding' started by Rickk, Dec 26, 2012.

  1. Rickk
    Joined: Dec 2012
    Posts: 1
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Sarasota, FL

    Rickk New Member

    Hi All,
    I am a long time lurker here.
    I am starting a rebuild of a '71 170 Aquasport which I've owned since '88 and actually did a little restoration on it in '98 (new floor and stringer repair) and facelift in '00.
    This is what the boat looked like in '00 when I was done and for the most part looks the same today, from the outside at least.


    I started to get some floor deterioration where the floor met the casting deck and I dove in and cut the floor out
    Here is what it looks like now:



    and eventually this - the point of no return.I will lam 2 layers of new glass on the inside of the hull before I start stringer rebuilds.

    I have added some layers to the inside of the transom and just 2 days ago put in the new transom core (2x3/4" marine ply with 3/4oz, 1708, 3/4oz between it).

    You can see the clamping going on and my buddy Ed, mixing some more resin for new stringers.

    I found an old "new" 27gal Inca belly tank for the boat - this boat always had a tank inside the console above the floor so adding this will free up a ton of room in the back of the boat.

    This is where my questions begin.
    I decided to make some forms for new stringers to match the shape of the originals and I made two forms - one with angled sides on both sides and one with a 90 on one side and an angled on the other.

    The pic above with Ed shows the double angled form getting ready to lam it up. I lam'd 1 continuous 1708 and then added the cutoff of 1708 in the bottom. Then I added a 12" piece of 1708 on each side overlapping the corners. Topped the bottom off with 2 layers of 6 or 8oz mat.


    Here is the 90 degree one - look at the other end and you can see the 90.

    So anyway, I'm getting the pieces of the puzzle together and now need to figure out the exact stringer layout. I had 3 stringers as seen in one of the pics above. but I don't think I can use 3 anymore due to the tank.
    The following drawing is what the thought is

    I know that I need continuous longetudinal stringers for strength and I think I can fit 2 in.
    The stringers I made are 5.5" wide at the top and about 9" wide at the bottom and are roughly 11-12 inches deep. I would like to raise the floor an inch or two to facilitate self bailing - as she sits right now (see top pic) the scuppers are under water at rest. Plus I'll need that height to accomodate the new tank.
    The drawing shows that the chine width at the transom is 63" and it starts narrowing and at the front of the tank is 55".
    If I move the stringers in from the outside 14" (outside stringer top measurement) I think I can can get about 135" of stringer before they disappear into the hull. This unfortunately runs through the tank so here is my question.
    At the top of the drawing you can see the profile of the stringers and the profile of the tank. I need to notch the tank a couple inches into each stringer to allow this to work - will that still give me good strength? I will glass the cutouts back in, inversed as a ledge.
    I will use the 90 degree stringers as bulkheads for and aft of the tank.
    I think I supplied enough pics to give you a good idea of how she sits in the water, the old stringers and drawings to help you visualize the plan.
    The console back edge was 64" from the transom so that is where I started the back of the tank - might move it forward 2 more inches to allow the pie cover for the fuel feed and gauge to be inside the console flooring.

    Any questions? I'm hoping you guys can help me out here.
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