I am hoping Matt Miller and the Hobie techs will be able to advise on this question.


Essentially, it involves the question of putting a small amount of non-toxic anti-freeze (say 1/8 to 1/4 gallon) into each H16 hull for the winter. This is what we sometimes do in the bilge of the big boats/yachts around here. The anti-freeze (the pink RV Plumbing stuff) guarantees that any trapped or missed water will not freeze hard enough to cause any damage.

I am interested in doing this with my H16 because I have to store my Hobie relatively level (as opposed to elevated for drainage) and it seems there is always a little H20 present in the hulls from condensation. Whether this is enough errant water to cause freezing damage I do not know, but I`d rather not worry about it through the winter.

I have viewed the cross-section photo of the inside of the H16 hull and it seems to me that this may be a good solution - one which will allow me to safely store my Hobie as I have described - regardless of errant H20.

Also, the photo seems to illustrate that the foam core does not extend as low as the keel; thus minimizing any seepage issues into the core that could occur from an unseen inner hull defect.

Any thoughts on this? I would also leave the drain-plugs in - but very loose.


Dave

I have never heard of damage to the H16 hulls from freezing water. The issue may be worse with water rather than ice, but water absorbed into the glass structure and then freezing might not be good. Still, I have no history about freezing damage to a 16, 18... just water in wing tubes and mast extrusions.

Dave: Take out the drain plugs and drain real good. Leave out the plugs and your good for the winter. I have been doing this for many years in Syracuse and never had or heard of a problem. Even if a small amount of water finds it way in to the hull it has lots of room to expand. It seems to me your introducing a potential problem by adding fluid and closing up.

Thanks for the reply Matt,

It sounds to me like I may be worrying too much about this with the Hobie. In many other designs of boats this can be a very serious issue.

As you know, it doesn`t take long for several ounces of condensation to collect in the hulls. And, due to my particular storage situation, I am forced to leave a small amount of water in the hulls to freeze. The interior geometry of the hull does look as though water should safely expand upwards as it freezes. In addition, unlike other boats, there are no stringers or bulkheads for entrapment.

Still good to have a little reassurance.

Thanks


Dave

Pat,

We posted almost simultaneously, so I did not address your response. In any event, thanks for the info. It is exactly what I need to know. The anti-freeze route is certainly not my first choice on this type of boat. But neither is storing my hulls horizontally (actually a little nose-down) whereby they cannot continuously drain. I have already drained as much as possible with the boat on the trailer.
I just need to feel comfortable with the little bit of water left behind to freeze.

Thanks again guys,


Dave

If you are really worried about the condensation you can get cans of dessicant to put in your hulls. I've seen them at West Marine. You will need ports installed for access.

If you leave the drain plugs open all the way you will be fine. I have stored both of my Hobies all winter like that. At some point in time water does condense and freeze. No damage to either boat ever occurred.

I fully understand the concern... you put many hours into restoring your boat.

How about a little hood / gutter over the opening when the plug is out to help deflect water? The hull would be vented and water (rain) could not enter.

Matt,

I have that looked after. The whole package is covered from the elements by a custom canopy over top of a Hobie cover.

Nick,

I use 6 containers of the stuff you`re talking about (made by Starbrite) every year on my other boat. It`s great stuff, but you`re right - it would only work inside a Hobie that has large access ports. It does keep the air dry and prevents mildew. But, it is not a substitute for drainage.

I think I will go with everybody`s suggestions. I will drain as best I can, then let the remainder freeze.

I am just glad to have this resource (catsailor) whereby I can get the answers to my questions and feel comfortable with my concerns.

Thanks to everybody - as always.


Dave