Transporting in Freezing weather

As I start planning a few months ahead for trips, I was wondering how the hobie kayaks withstand cold weather.

How well do they tolerate say 10 deg F (-12 C) weather being transported on a rack on top of a car? I suppose the answer is "it depends" but are there any guidelines or experiences?

I can see cranking down on the straps and having it explode because it got cold and brittle. That would NOT be good.

I can understand your concern.
Yet if there is any doubt, double up on the tie downs and keep them at different tension levels (very slightly). That will give you an idea what works best.

Best regards from Vancouver Island, where it's not so much about minus zero but rain, rain, and more rain...

If there is still any doubt, double braided nylon fore and aft tie downs are a must anyway..that would give you 3 different ways to check on your ability to keep it on your roof. (the fore and afts use a trucker`s hitch which will not fail you unless you live in polar regions)

Edited: You asked as how the Hobie would perform in sub zeros on your roof. Consider that the means to repair a dent is to soften the hull my boiling (or very hot) water to the hull with added internal air pressure, the opposite would hold true as the hull becomes hard and possibly brittle. In that case, it would seem that cranking on the tiedowns would be also a bad idea as cranking the tiedowns in very warm weather.

Having a good cradle that matches your hull config seems as important as applying the correct tension to any roof (or fore and aft) tiedowns.

Best Regards
Trinomite

_________________
Always looking for ways to make good things 'Gooder'

Thanks Trinomite. All very good points. I was asking for this winter but last weekend, it was below freezing already on the morning drive to the launch. Well that's the price of living in Alaska!

More generally my concern is what might happen at say 10deg F (-12 deg C) if I were to drop the yak from a foot or two. Or I am fishing and bang my net on an exposed frozen part of the kayak?

Does the rudder lines fail? How about the components of the mirage drive?

I know from snow machining that there are plastics that are impervious to the cold, and then there are others that turn into brittle shatter packs the instant it gets slightly cold.

Seeing all the Hobie promotional videos and pictures of sunny southern california yakkers with barefeet and shorts doesn't necessarily instill cold weather confidence though it seems to be doing great so far!

Alaskan here... I've never been too concerned about any of the plastic parts becoming too brittle.

The kayak has been on and off of my vehicle every year until at least December. The only problem I have had is showing up to the launch too early when everything is still frozen solid and the rudder lines are frozen. I'm assuming they were frozen in the tubes ('07 Outback). I'd just paddle for the first hour or so and never use too much force until the rudder control moved with little effort. It has always thawed out for me. If there is no sun and its less than 15 to 20 degrees all day I'm not on the water so this may not apply to you if you're still searching for fish when its any colder.

The lines are frozen only on the second or third day of a fishing trip when the kayak goes on the car kinda wet. If you allowed it to dry at home and showed up on a cold morning I wouldnt worry too much about any of the plastic on the kayak itself.... the only thing I've snapped is the cheaper plastic buckles that adjust the seats.

Thanks Shaggrugg and my apologies for not replying sooner. Well it's almost November and I am still using my kayak. While air temps during fishing has been in the upper 30's to mid 40's, that's not going to be the case here really soon.

I have full intentions of making whatever modifications are required to be able to fish my Hobie outback in the dead of winter here in southcentral Alaska. As you pointed out, anything in the water is might be okay...after awhile. But I can foresee winter trips being shorter and waiting an hour to unthaw while on the water is a MUCH higher percentage of daylight hours and that's not acceptable to me if a solution can be found.

I am willing to add an internal heating source whether it is for transport or on water. Of course the trick is to have a source of heat, hot enough to be effective but cold enough that it doesn't melt through the plastic in the worst of cases.

I was hoping someone from Hobie could tell me the different characteristics of the plastic used. I wonder if they wouldn't ship me a decent size piece of the plastic so I could just leave outside or throw it into a freezer so I could see for myself. Maybe its some kind of plastic that handles well in the cold. I have plastic components on my ice fishing gear or snowmachines that have no issues. Of course I have taklen other gear out which is VERY sensitive and becomes extremely brittle as soon as it gets slightly cold.

A catastrophic hull failure, let alone a rudder failure, while on water, in Alaska during winter is just that...catastrophic!!!

Anyone have any ideas or a contact within Hobie that can answer my questions?

I caught three kings out of Homer, AK last weekend but the weather was perfect. If I wait for weather like that, I'd be waiting till summer.

Thanks in advance for any info!!!!!!!

The technical term for when a plastic turns from a rubbery elastic material to a rigid brittle material is the glass transition temperature. Hobie manufactures their kayaks out of polyethylene which has a glass transition temperature somewhere between -90C and -110C.

So, stay away from -90C temperatures and you should be fine.


elaborating further: On the hobie kayak page it says "Each Hobie Kayak is a seamless, roto-molded, polyethylene torpedo." There are many different kinds of polyethylene, classified by either the density of the plastic or the average molecular weight. Most consumer products made of polyethylene are classified by weight usually falling into these categories:

LDPE=low density polyethelene
think plastic bags and cling wrap

MDPE=medium density polyethelene
pipe fittings, shrink wrap

HDPE=high density polyethele
Milk jugs, laundry detergent containers

I believe they use medium density polyethylene [MDPE], since that is what is typically used in this application. HDPE will have a lower glass transition temperature and as a result plastic milk jugs will go brittle before your kayak.

Here is a link to the ppt where i found the glass transition temperatures (slide 20)

http://docs.google.com/viewer?a=v&q=cache:ftuyupoU7EgJ:www.mse.mtu.edu/~milligan/my3400/polymer_review.ppt+polymer+review+my2100&hl=en&gl=us&pid=bl&srcid=ADGEESjik-EgkwbXxy72rRU53kLjCyesr6fpBW47RUmE6-Yh0Y5jpiDq0YKHC2QS2emQDiyV31plfK1XSsc9rfBIAdjL650KC19CupssonmUlLTOIDyp1lNDfB8z5wHeFpkYlq6cKGYO&sig=AHIEtbRCFmUN7wbAaJngFDsfgSDqrEkX5g

thanks to Dr. Milligan for putting his lecture slides online for me to find