Tuesday, April 18, 2017

Model testing 4/2017


We have 3D printed pieces for a catamaran and a swathy design.   We glued the pieces together using gorilla glue and clamps to hold while the glue foams up and hardens.  Then we paint the whole thing with styrospray to make sure it is waterproof.  
Catamaran in clamps while glue dries

Amoni with Catamaran model - printed as 10 pieces 37.5 inches
Swathy design - printed as 8 pieces


Amoni making a test wave

Both the swathy design and the catamaran were weighted down with cups of gravel to 2.56 kg.  The catamaran did not take much weight, about 1/10th kg.   The swathy design was close to 1/2 kg of gravel.

The above video shows the setup.  We make the waves at one end of the pool using a 12 inch diameter PVC pipe.  The tension holding the models in place is just from the weight of a rope to the top of a lounge chair.   The "infinity pool" edge dampened the waves some but we had the pump off because it was making waves and with the pump off the pool soon got below the edge so only large waves went over.   The camera for most of the video was on the tripod in the middle of the infinity overflow.

I think the following videos should be viewed full screen and you can also use youtube to slow them down by a factor of 4 to study interesting parts.

First waves hitting from the side:

Next waves hitting on the bow:

Then two older models.   I did not actually use the best of my older models but it then got windy and so other tests will wait till next week.  The orange model with 4 floats is 8 lbs.  It should have been weighted down to about 12 lbs for optimal stability.  Maybe in a future test.

 In these videos the catamaran really looks good.  It is hard to beat but I still want to try.



This next video the model on the left is 4 lbs with 1.1 lbs of gravel in cups for a total of 5.1 lbs.  The catamaran total is 5.64 lbs.   This one does well against the catamaran.

3 comments:

  1. Have you seen this?

    http://newatlas.com/glider-ss18-yacht/45155/

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    Replies
    1. what if this ss18 were designed as a trimaran and the middle float also supported a mast?

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    2. I have seen it but it is interesting. I like it as a way to get a "large size boat with small displacement". I think large size makes waves feel smaller and small displacement keeps costs down.
      A trimaran like this has the problem of weight up high and so needing lots of flotation on the amas, so might as well go catamaran, I think. Thanks.

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