3.5m HDPE jetboat

despite what someone people may say this stuff can not be glued, it has to be mechanical ie welded or screwed together

the boat is very rigid now, if i sit on one corner and another person sits on the opposite and we rock the boat their is very little distortion but before i welded the sides up i could get both ends to touch the ground

 

http://m.youtube.com/#/watch?v=lYPFATFM9ZA&desktop_uri=/watch?v=lYPFATFM9ZA&gl=NL
http://m.youtube.com/watch?feature=related&v=ntJG5YR7L-0#/watch?feature=related&v=ntJG5YR7L-0

 

I like it, diffrent anyway.

 

With flame treatment and the right glue, gluing HDPE is somewhat effective. HDPE looks even more attractive when foams, reinforcing fibers, cross linked PE, pressurized compartments and molded in metal reinforcing are considered.

 

VERY nice work, first i've seen of sheet plastic made into a boat.

Couldn't you somehow laminate a thin sheet over an aluminum hull
to get its advantages without the extra weight?

Does marine growth attach to HDPE like most surfaces?

 

Thanks for the information.

Some HDPE kayaks and even fiberglass ones that sit 100 % exposed look somewhat faded where the sun hits after a few years. Maybe just the surface color or sheen affected as they still seem to be quite strong. Perhaps there is a dressing like armorall that helps...

I wonder are the rotomolded boat hull structures thicker in the critical stress areas, or just uniform thickness all around, like those being made by welding (except for thicker joints) ? Seems like trash cans, barrels, and dock floats are uniform thickness, but these are not critical structures...

Porta

 

You can see the variation in thickness on this cross section:

http://www.extractorsled.com/picts/MEGA/MegaHullCrossSection.jpg

 

Pioner boats video explains it all (for rotomolded boats):

https://www.youtube.com/watch?v=abKTUi5Yd9s

Triumph boats in the US are built this way also...but they totally foam fill them.
They are high density PE I think?

Pioner are low density PE. Hollow on inside. Some foam slabs inserted.
Maybe that works better in cold water?
More flexibility at low temps?



The Leister extrusion welding guns to make PE sheet boats are very $$$
The S2 is $5600 USD I think?
Cheapest decent extrusion weld guns are $4000.

Our NZ friend borrowed his S2 for the jetboat build possibly?

 

alloy has a very high cof compared to HDPE so it grabs when you touch the bottom, most ppl put a strip down the delta to help it slide better

the plastic got to about 70 deg c the other day in the sun and grows about 10mm/1m

 

i did borrow it to begin with but ended up buying one instead

 

i used to work for a company in New Zealand making rotomoulded boats, to get it thicker the area of the mould was sprayed with black paint to get the area hotter their for making that area of the boat thicker

http://www.marinerevolution.com/sw2400.htm

 

engine bearers made tonight, ill dry fit the engine in over the next few days and start tacking it all up, almost getting close now

 

i got the engine it tonight, i forgot how heavy it was, looks like its going to come together nicely

 

This is AWESOME! Cool stuff so far! What motor are you using? Is it the Polaris motor that's from the same Polaris Ski your pump is from? Can't wait to see more!

 

yea its a 1999 Polaris 1200 fetich Genesis i imported from USA. i have stripped just about every nut and bolt from the ski, its surprising how many they have and its saved a lot of money, apart from the cost to build the hull the only other item i will have to make/buy is the intake grill, i have some ideas of how to optimize its performance and reduce the chance of stones getting jammed in the grill, preventing those mid winter swims