Houseboat weight

Yes, in the 3.5m HDPE jetboat thread, the builder reports: "the plastic got to about 70 deg c the other day in the sun and grows about 10mm/1m".

As you point out, any design where this expansion can cause stress problems, will have to accommodate this somehow.

I'm wondering about the scenario in which a larger boat with a full HDPE deck, is out on the water under a hot sun. It would seem that deck expansion would start to rip away from it's anchoring to the hull structure, as CDK described above.

Thanks for sharing your experience.

It's definitely easy to weld and robust, as shown here:

 

I'm curious as well.

Here's one http://www.leister.com/en/plastic-w...&product=de984f74-6631-44bb-bad3-a7f9ef314783 that is used in this video from the other thread:

 

The extrusion welder I used was a Leister ....S model I believe. I hired it as at the time purchase of a new one was outside my cashflow and I couldn't find a second hand unit. They are around $6000 new . If I did another I would buy and then sell on afterwards , as it would be less than the hire cost. That way I could take my time more as well without seeing $ signs tick over by the day.

 

Hi, My experiance wasn't the same for expansion however my HDPE was much thicker and also as a pipe so I get was resisting the expansion within itself. I would not think that HDPE would be very good as a large flat surface . I think it would ripple and buckle as it heated and cooled. Cored hdpe may be better in this regard - black color would certainly be the worst.
As a pontoon hull I think it is idea ( it negates all the traditional drawbacks of other hull materials in a houseboat situation) but for exposed superstructure probably not ,and would have no significant benefits to offset the weight of the material.
There are several manufacturers making larger rotomoulded HDPE boats successfully and also specialist fishing and rescue boats out of hdpe sheet and pipe ( see the Aquatruck) but not on the scale of a launch or houseboat.

 

Cored HDPE? I'll have to look that up.

I think your summary is spot on: it's excellent candidate construction material for buoyancy components when shielded from solar heating.

BTW Scotty and CDK, the Aquatruck is 20 feet long, black and is NOT roto-molded. According to the product brochure it is an HDPE extrusion welded hull, fully framed and ribbed, with a minimum 10mm thickness, and pontoons that are minimum 13mm thickness.

It has quite a bit of surface area exposed to the sun so how does it not warp and distort?

 

I think pipe doesn't distort as much because of the inbuilt contaction stress. To explain.... I found that when I cut a longtitudanal slot in the large diameter pipe , the pipe slowly squeezed the gap in a little. A ring cut off the end and then cut through also contracted so the ends passed each other. As a rough guide a 1000mm pipe wanted to relax to about 950mm diam. To my mind this means the pipe is in a "stretched" form when made. Therefore when heated all it does is relax some of that " stretch" by expansion.Its just a guess but it does explain why less expansion is noticible. As for some flat areas not expanding - this may be because the material is elastic to a certain extent.When unrestrained it will expand but when fixed or welded into a structure it can absorb a fair bit of those expanding forces by compressing.

 

HDPE pipe does distort, and quite a bit. It is well known for this.

I bet the aquatruck does change shape. But it's the same material and quite flexible so it just "moves" together, and returns to the original dimensions when it cools off.

 

Floating Touristic Ecovillage Project )

ROTOMOULDED HULLS FOR AFFORDABLE FLOATING ECOVILLAGE ???


Dear Sir,

site to download our pdf : ecolodgesocial.blogspot[dot]fr or ecotourisme.businessplan.over-blog[dot]com

Mr John Venier, the coordinator of the WAVE International initiative ; Wetlands, Coastal and Marine Resources Management through Mainstreaming EcoAgrotourism based on local community empowerment, asked me to contact you to introduce our sustainable-tourist mainstreaming model initiative, targeted to empower women, youth and fishermen and farmers in the wetlands and coastal regions of emerging countries around the globe.

The aim and intention of our initiative is to create an actual operational model which will give life force, or which will empower international and national support programmes such as the Global Environmental Fund, UNPD, UNEP, etc.... ( The GEF and/or OTHERS NGO grants funders for marine and coastal management programs.) Our initiative, WAVE International, is unique in the world in that it uses breakthough innovation and available resources such as GSTC, STEP, SIFT, to enable wetland communities to create and invest in their own local economies by creating floating eco-villages and eco-resorts.



Our international initiative will support local marine and wetland communities in four major areas. WAVE International will:


1. Create local eco-touristic industry and access international sales markets for local communities' products and services by building floating or partially floating villages for tourists visiting wetlands and coastal regions in countries all over the world. These locally managed floating eco- touristic village and eco-resorts will be self financed from over 3 to 5 years on an average. Such extraordinary rapid self financing measures defines a kind of new and BREAKTHROUGH INNOVATION for the economies of emerging countries' coastal communities by downsizing resort models from 4-5* to 3* ECOLODGES making them affordable to the local residents of these communities and therefore attractive for local re-investment (social business) which would balance the potential loss of fees/night by originality, social link, cultural educational art center, agro-tourism, biodiversity and nature discovery tours to raise up to 150-300 usd a night. Our Gabon, Java and Cost Rica (or Colombia) sites are targeted to be our pilot/demo floating eco villages and eco-resorts.

2. Empower local communities thereby, to create their own jobs, (especially jobs and career paths for the women of these under developed countries as women are often excluded from the higher paid work force and left with only menial employment). We would assist and guide the construction of these floating movable/mobile ecovillages (the design of whch are inspired from Asia) but it would be the local people who would build, manage, run, own and finally profit from their personal investments and creation of these floating villages which would in turn attract tourists of all ages for bio-diversity studies, water sports ( windsurfing, diving, fishingm snorkeling, sailing) and leisure activities as well as exploration tours of the local flora and fauna. These floating communites and eco resorts would also draw university and scientist research groups from all over the world.

3. Provide a means for local communities to fabricate floating village units in their own workshops and factories, using local and renewable building materials such as bamboo, natural fibers, coconut wood, wicker and reed and other natural materials for both local and international sale and exportation. As well as fabricating floating village components for export sales, our initiative will support local communities to engage in seafarming and to build fisheries for a vital and sustainable income for local people.

4. Protect and celebrate wetland regions which are often neglected or exploited by mining and deforestation. WAVE International is an ecological and low impact initiative that strives to promote and participate in coastal and wetland management and conservation.

As the English (and German) speaking correspondent for WAVE initiative, I would be grateful to be able to speak with you on the phone about our project and possibly find ways in which we could collaborate.

Mr Venier would like to invite you to attend our "FUTUR EN SEINE" event on June 19th and 20th, 2013 in Paris. He would also like to invite you for a private meeting, on any day between June 24th and 28th of june, or whenever it would be convenient for you.



Please contact Mr Venier at the above email address for more informations or help :

- by supporting the project (communication, TV, LABEL,conference, dissemination etc..)
- by helping (technically)
- by funding the project(s)
- by duplicating it.

Wishing you a lovely day and looking forward to hearing from you soon.
Ms Julie P., WAVE International, English Correspondent