alum floor in my jon

Discussion in 'Boat Modification Journal' started by 4bratsdad, Aug 16, 2009.

  1. 4bratsdad

    4bratsdad Member

    Messages:
    241
    State:
    illinois springfield area
    just got a 1652 polarkraft gonna put the floor in this week, picked up 1 1/2 " sheet closed cell foam. how much is sheet aluminum 16th"??? local places not open till mornin, dont wanna do the marine plywood its heavy, think galvenized sheet would be as heavy, i was thinkin 80-100 bucks, but friend told me more like 500 bucks, if thats case ill run to lowes today do the plywood, anybody buy any lately??? i know scrap price is nothin now
     
  2. brownie525

    brownie525 New Member

    Messages:
    1,505
    State:
    Nj
    Go with the plywood
     

  3. SWeiss

    SWeiss New Member

    Messages:
    751
    State:
    Pennsylvania
    Aluminum? I have tile floor in my john. Makes it easier to caulk around the tub! :smile2:

    Seriously though. Go with 3/4" treated or marine grade plywood.
     
  4. kyleco55

    kyleco55 Well-Known Member

    Messages:
    1,359
    State:
    Central In

    your right there.. but the prices are still high for new material. IF you decide to go with the aluminum floor, definately check
    ALL scrap yards in your area. i know around here, they keep stuff like plate metals, and resell for a small profit.. ALOT cheaper than new!:wink:

    :0a26:
     
  5. cantstopgrandma

    cantstopgrandma New Member

    Messages:
    955
    State:
    MD
    If you can afford it, i would go aluminum. Aluminum will last as long as the boat. The price will depend on weather you want diamond tread or just sheet aluminum. Either way, a 4x8 sheet will probably run you $200 or more. I used street signs in my jon, got them from the county roads dept for FREE. I covered mine in outdoor carpet, so you cant see the bullet holes.

    Whatever you do, do not use treated plywood. The treatment contains tons of copper, which will react with, and eventually eat your aluminum boat.
     
  6. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    3/4" plywood is alot of overkill.
    For some reason people think because 3/4" sheeting is used in house floors it's used in boat floors.
    I build entire power boats from plywood and rarely use 3/4" plywood. When I do it's for stringers and transoms.

    Marine plywood. Another place where people tend to screw up.
    I'm highly edumacated in marine plywood. I've used a bunch of the stuff. Bought a bunch of the stuff.
    Not much I don't know about it.

    Main thing to know, it's not treated with anything to prevent rot.
    If this is what you've been told or taught it's a lie.
    What deems it marine quality plywood has nothing to do with rot.
    In fact many species of marine plywood will rot quicker then southern yellow pine. Imagine that.

    There is one brand that has some level of treating but it's not a full blown rot prevention treating. You still have to epoxy it.
    That brand is also not prevelant in the market either. I have used it but I'd rather use Meranti BS1088 (BS is British Standard) or Okume BS1088 (also known as Gaboon).
    What helps against rot is that there are no voids in this plywood. No voids for moisture or water to collect, sit, and rot from within. Voids are common in your run of the mill plywood.

    Best way to look at marine plywood is from the mechanical stand point.
    It is the perfect plywood. It carries the British Lloyds stamp. If it don't, don't buy it. An example. Many boat plans allow for construction of some hulls with regular plywood but it is recommended that planing hull bottoms be built from marine plywood. Not because of water contact. Because of it's STRENGTH!

    Back to the floor. Since you are laying foam in the floor that will give you support. If it were me I'd go with 1/4" marine plywood glass 2 sides with 6oz cloth and epoxy. If you don't want to pay 40 bucks for marine grade buy an exterior grade pine or fir depending on your location.
    It'll outlast the aluminum the boat is built from with a little care and be alot quieter.
    Damn an aluminum boat. Things are entirely too noisy for fishing.
     
  7. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    Something I forgot to mention.
    A pilot doesn't jump in a plane and fly without knowing his CG. Well some stupid ones do that wind up crashing.

    Weight is just as important on a boat as a plane. You want to minimize weight. Weight should ALWAYS be first and foremost in thought when modifying or remodeling your boat.
    It's real easy to turn a good handling boat into a dog of a boat. It doesn't take a professional to do it.

    3/4" treated plywood weighs on average 86 pounds a sheet depending on moisture content.

    1/4" exterior pine about 26 pounds per sheet. By the time it's glassed epoxied and coated let's just call it a round 30.
    Marine grade Okoume. About 18 pounds per sheet.

    But you see how quick this adds up. If you used two sheets of 3/4" you've permanently added the weight of another adult male to the boat.
    If you use one sheet, you've permanently added the weight of a bag of Sacrete.

    Building boats you often say oh well I'll save a little money by going with this marine grade over that marine grade and it's only 10 more pounds a sheet.
    Only 10 more pounds. What if there is 20 sheets of plywood in the boat? 200 pounds added weight.
    What are really talking here? Permanent additional costs.

    That 200 pounds could throw me over into the next size motor and cost me a 1000 bucks. That 200 pounds will always cost me in fuel mileage.

    Weight consideration is always important. Especially in aluminum boats.
     
    Last edited: Aug 17, 2009
  8. 4bratsdad

    4bratsdad Member

    Messages:
    241
    State:
    illinois springfield area
    just picked up material for my floor, it's made locally by a company called nudo products they mostly make stuff 4 shower walls & carwashes, but i remember my buddy giving me a half sheet of this stuff that looked like masonite paneling w/ aluminum glued on ea side, well they have several products like that, the "meat" on the sandwich is a plastic product waterproof, they sell it mostly 4 street signs, 23lbs, downside is aluminum has a slick powdercoat finish, only comes in colors, i got hunter green, think im gonna put some of those black sticky treads for steps or such on it, i like it 4 the hoseability, but muddy boots& cat slime would not go well with this, thought about ruffin it up but its like a slick appliance finish 50 bucks more durable than plywood,total thickness bout 1/8"