The short & sweet of rotomolded polyethylene kayaks and boats.

A lot of people ask us what the kayaks and boats are made out of that we sell. Which is an understandable thing to ask, I'd want to know what I'm buying as well. Most of our kayaks and boats have a rotomolded polyethylene hull construction. Which I know means zilch to a lot of people - hey, it's okay, it took me a while to fully understand it when I first started working at Fogh. Rotomolded Polyethylene in plain English means that the kayak or boat is made out of plastic. Our boat builder Adam, a certified Composites Technician, gives us the low down on Rotomolding & Rotomolded Polyethylene. 

Now let's break down the process of rotomolding so we all have a better understand of what the heck rotomolding and rotomolded polyethylene is. 

Old Town Predator

Rotomolding is a short way of saying rotational molding, which is just a mold that gets rotated during the cooking process while Polyethylene is a type of plastic, the most common to be exact. Companies, like Hobie and Old Town, use rotomolding because the process allows them to make long, hallow shapes - like hulls. 

The process in it's simplest form goes something like this: 

1. Make mold. 

This is arguably the most important part of the process as the mold is what shapes the hull and holds value. 

2. The mold is filled with polyethylene pellets, which come in bags in different colours .

3. The filled mold goes into the oven to cook while being rotated. 

The pellets melt from the heat of the oven into a liquid like state. The rotation forces the liquid polyethylene to coat the entire mold surface evenly.  

4. The cooked mold comes out of the oven and is cooled while still being rotated.

5. Release the cooled polyethylene from the mold.

6. Finish the edges so they're all nice and smooth.

7. Moves on for the rest of assembly. 

Simple right? Well at least it sounds simple but it does take quite a lot of work. 

We have people ask us all the time what the difference is between polyethylene and Fiberglass hulls - Which is better, Which is better suited for cottages and/or families? Take a deep breathe, we're going to tackle all this. 

Let's jump right in with Polyethylene vs. Fiberglass:

- Polyethylene is more cost effective.

The process is quicker & easier than Fiberglass. Fiberglass (cloth + resin) is laid by hand over top of the mold then the resin has to cure before you can take it out of the mold. In comparison, polyethylene you pour out of the bag, into the mold and then it goes into the oven. So material wise & labour wise, Fiberglass will increase cost. 

- Polyethylene is more durable.

Let's say you have a cottage and there's rocks where you launch or along the shoreline, the polyethylene will hold up better if the hull(s) come into contact with those rocks in comparison to the Fiberglass. Basically, Polyethylene is highly durable and more impact resistant than Fiberglass. 

- Polyethylene is more for recreational kayaks and boats whereas Fiberglass is more performance oriented.

For example, the RS400 Hobie 16 are made out of fiberglass whereas the RS Quba and Hobie Getaway are made out of rotomolded polyethylene. 

- Polyethylene is easier to repair. 

Have more questions? Give us a call at 416-251-0384, send us an Contact Us or drop on by the store. Any Fogh Marine employee would happy to assist you! 

Tags: rotomolding, polyethylene, polyethylene kayaks, polyethylene boats

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