Chinese Rafts

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Kazzer
    *********
    • Aug 2008
    • 2848

    Chinese Rafts

    Click image for larger version

Name:	IMG_1616.jpg
Views:	1
Size:	86.8 KB
ID:	102142

    Just bought myself a Harborfreight 6hp motor and a LONGTAIL Motor Kit.

    I fell in love with river rafts while in China and have decided that The Erie Canal deserves at least one!



    So in March, we'll be ordering 8 x 20' lengths of 6" plastic pipe (my bamboo) and we'll start bending it to kick the bow up a bit.

    Planning this is keeping me busy these cold winter days!
    Stop messing about - just get a Sub-driver!
  • trout
    Admiral
    • Jul 2011
    • 3545

    #2
    Ah I see, you're building a 1to1 model of a river raft. Very clever indeed.
    If you can cut, drill, saw, hit things and swear a lot, you're well on the way to building a working model sub.

    Comment

    • herrmill
      Commander
      • Dec 2008
      • 360

      #3
      Nice to see your idea progressing but why use PVC when large size bamboo in long length shouldn't be hard to locate?




      BTW, I found the perfect companion for that new raft to help keep your beer cold, and portable to boot! Who knows, you might even create a new market selling iced lollies during the summer months. :wink:

      Click image for larger version

Name:	2012_Newest_design_DC_12V_100L_solar.jpg
Views:	1
Size:	45.5 KB
ID:	75679

      Comment

      • Kazzer
        *********
        • Aug 2008
        • 2848

        #4
        Originally posted by herrmill
        Nice to see your idea progressing but why use PVC when large size bamboo in long length shouldn't be hard to locate?


        Aha! Two reasons - bamboo only 12' long, mine will be 15-20' long. ..6" diam bamboo = $4 a foot + shipping. 6" PVC = $2.60 inc shipping and I can get 20' lengths.



        Originally posted by herrmill
        BTW, I found the perfect companion for that new raft to help keep your beer cold, and portable to boot! Who knows, you might even create a new market selling iced lollies during the summer months. :wink:

        [ATTACH=CONFIG]18224[/ATTACH]
        Hmmm! Taking the ****, are we?
        Stop messing about - just get a Sub-driver!

        Comment

        • He Who Shall Not Be Named
          Moderator
          • Aug 2008
          • 12256

          #5
          Mike, you will be the one guy spending all your time pulling grass off the canal bottom.

          And I think your PVC pipe will be too floppy. You'll need the rigidity of the Bamboo me thinks. I have a minds eye movie running in my head showing you fire-walling the throttle only to see your prop start to whip-lash around like an unattended fire-hose. "New York family of four decapitated in bizarre boating accident ... film at Eleven!"

          David
          Who is John Galt?

          Comment

          • Subculture
            Admiral
            • Feb 2009
            • 2119

            #6
            Bamboo is about a third of the density of water, PVC tends to be about 50-60% heavier. Polypropelene pipe partially filled with foam would give you something approachimg bamboo.

            Balsa wood is the best naturally occuring material for raft building, infact it means 'raft' in Spanish

            Comment

            • Kazzer
              *********
              • Aug 2008
              • 2848

              #7
              Originally posted by Subculture
              Bamboo is about a third of the density of water, PVC tends to be about 50-60% heavier. Polypropelene pipe partially filled with foam would give you something approachimg bamboo.

              Balsa wood is the best naturally occurring material for raft building, infact it means 'raft' in Spanish
              If I need to increase the buoyancy, I'll just add another pipe, but I've studied the Chinese pipe boats, and they work fine.
              For example a 24' long 6" pipe displaces 294lbs water, cut that in half for safety sake, and we have 150lbs. 6 pipes = 1000lbs

              Plastic doesn't absorb water or rot like bamboo.
              Plastic is cheaper.

              It ain't broke guys!

              Watch my video in previous posts.
              Stop messing about - just get a Sub-driver!

              Comment

              • trout
                Admiral
                • Jul 2011
                • 3545

                #8
                PVC exposed to sun turns brittle. Must be painted - perhaps to look like bamboo!
                If you can cut, drill, saw, hit things and swear a lot, you're well on the way to building a working model sub.

                Comment

                • Subculture
                  Admiral
                  • Feb 2009
                  • 2119

                  #9
                  Most PVC pipe will have stabilazers put into it to prevent that happening. Pretty much all guttering, downpipes, waste pipe and double glazed windows in the UK is PVC based, and out in all weathers, unpainted.

                  With hollow pipes you're relying on the air inside to provide bouyancy, okay in calm conditions, but if you get choppy water....

                  Comment

                  • trout
                    Admiral
                    • Jul 2011
                    • 3545

                    #10
                    That may be. I was thinking of the white type used in sprinkler systems. Here in Las Vegas, if left above ground, turn a nasty brown and break easily. Is that the same you are thinking of or the black type piping?
                    If you can cut, drill, saw, hit things and swear a lot, you're well on the way to building a working model sub.

                    Comment

                    • Subculture
                      Admiral
                      • Feb 2009
                      • 2119

                      #11
                      The colour is largely irrelevent, as you can purchase pipe in various shades e.g. white, black ,grey etc. Unfilled PVC is actually clear, and you can purchase clear PVC pipe, although it tends be very expensive, presumably because there isn't such a big market for it.

                      Sounds like the pipe you have isn't designed to spend time in the sun, and hasn't been modified for ultra violet exposure. The early PVC base double glazing windows suffered from the same effect, they yellowed and went brittle. This understandably gave plastic windows a very poor reputation, as the so called lifetime windows neded to be replaced after just a few years. The engineers got to work, and came up with upvc, which has some chemical additive which makes the PVC resistant to ultraviolet. You can see plastic windows over 25 years old, and they still look fine, so clearly the chemistry works.

                      You might want to give the company that makes your sprinkler hose a call, and ask them why it is they can't incorporate technology that has been around for several decades. Either that or have a look for a different make of sprinkler hose, I'm pretty sure there will be a company out there that does supply a better product .

                      Comment

                      • trout
                        Admiral
                        • Jul 2011
                        • 3545

                        #12
                        I will stand corrected.
                        Here is a manufacturers description

                        The Effects of Sunlight Exposure on PVC Pipe
                        Occasionally we get questions about the effects of sunlight exposure on PVC Pipe and Fittings. We have put together this information to help answer some of those questions.


                        The sun emits visible and non-visible radiation. One component of non-visible radiation is ultraviolet (UV) light. Like many other substances, PVC plastics are affected by exposure to UV radiation.


                        The exposure of PVC to the UV component of sunlight causes PVC molecules in the first .001" to .002" of exposed surface to become permanently converted to a complex structure typified by polyene formations. The result is a brownish discoloration, often called "UV discoloration", "UV degradation", or more commonly "sunburned". UV discoloration does not occur where PVC is not exposed to sunlight, and ceases when exposure ends.


                        The discoloration process is time-dependent, and can be slowed with the addition of UV absorbers in the PVC compound. The most common additive used for this purpose is titanium dioxide, which also functions as a pigment.


                        Research has been done to determine the effects of long-term (two year) sunlight exposure on PVC pipe (see "UNITR-5: The Effects of Ultraviolet Aging on PVC Pipe", by the Uni-Bell PVC Pipe Association.) Other than visible discoloration, the following summarizes the results on pipe physical properties:


                        Physical Property Performance Characterstic Effect of Sunlight Exposure
                        Impact Strength Impact Resistance Decrease
                        Tensile Strength Pressure Capacity No Effect
                        Modulus of Elasticity Pipe Stiffness No Effect
                        Research indicates that the sole performance characteristic adversely affected by sunlight exposure to pipe is impact resistance (the ability of the pipe to withstand a rapid external force or violent contact). UV discoloration does not effect the pressure capacity of the pipe, or the pipe stiffness (external load capacity).


                        The degree to which impact strength is affected by sunlight depends upon a number of variables, including: time of exposure, climatic conditions, diameter of pipe, wall thickness of pipe, and type of PVC compound used. The thicker the pipe wall, the more unnoticeable the effect becomes. Care may be required when handling thin wall pipe to avoid impact or breakage, but once the pipe is installed however, there will be no effect on the pipe's pressure capacity, or external load capacity.


                        For permanent above-ground PVC Pipe and Fitting installations, it is recommended that the pipe and fittings be protected from sunlight exposure. This can be accomplished by wrapping the pipe and fittings with an opaque material, or more commonly, by painting it. If pipe or fittings are to be painted, a water-based latex paint for exterior use is recommended.
                        If you can cut, drill, saw, hit things and swear a lot, you're well on the way to building a working model sub.

                        Comment

                        • trout
                          Admiral
                          • Jul 2011
                          • 3545

                          #13
                          Originally posted by Subculture
                          You might want to give the company that makes your sprinkler hose a call, and ask them why it is they can't incorporate technology that has been around for several decades. Either that or have a look for a different make of sprinkler hose, I'm pretty sure there will be a company out there that does supply a better product .
                          My experience was from a house I bought and had to redo the backyard where a lot of the pipe was left in the sun. I ended up yanking the stuff out and replacing it in nice deep trenches. It was schedule 40 replaced with 80.

                          You amaze me in your breadth of knowledge.......Thank you for keeping me honest.
                          Peace,
                          tom
                          If you can cut, drill, saw, hit things and swear a lot, you're well on the way to building a working model sub.

                          Comment

                          • Subculture
                            Admiral
                            • Feb 2009
                            • 2119

                            #14
                            It's just something I remember the materials lecturer banging on about at technical college many moons ago. I would suspect that ultraviolet inhibits the properties of the most plastics. All materials stress and age over time.

                            Comment

                            • herrmill
                              Commander
                              • Dec 2008
                              • 360

                              #15
                              I'll make Mike an offer he can't refuse... I'll give you all the long-length big bamboo you'll need for FREE!!!. Heck, we can even make the raft for ya & strap on that new fangled electronic lolly cart if you'd like. :wink:

                              All you need to pay is the S&H from China.

                              Comment

                              Working...