[PSUBS-MAILIST] syntactic foam

[Sean T. Stevenson via Personal_Submersibles]

Are these floats hollow, or solid / blown closed-cell plastic?

Sean


On 2015-11-17 16:48, hank pronk via Personal_Submersibles wrote:
> I am not sure I would want to risk an impact with the floats that could
> weaken them and potentially have them fail at depth.  I feel it best to
> have them fully protected under a cowl.  I suspect your right that they
> are tough enough, but I wouldn't want to chance it.  I have seen a
> picture of a DW with about 20 floats tied to the front of the sub.  They
> must have had an over weight item mounted temporarily that needed
> compensating. 
> Hank
> 
> 
> 
> On Tuesday, November 17, 2015 4:30 PM, Sean T. Stevenson via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
> 
> 
> I only just now looked up the trawl floats.  I notice that they have a
> depth rating which may match what you need, and you may also be able to
> take advantage of the form factor, instead of viewing it as a
> restriction...  If the floats are available as spheres with a through
> hole, what about mounting an array of them down either side of your boat
> on a round bar which is part of the superstructure to serve double-duty
> as hard fenders?  Placing them outboard like that would increase your
> surface stability as well.
> 
> Sean
> 
> 
> On 2015-11-17 14:03, hank pronk via Personal_Submersibles wrote:
>> Sean,
>> I have looked at building steel buoyancy tanks- they are just to heavy
>> to be effective.  I am trying to keep the sub as light as possible and
>> trawl floats are better than 50% buoyant to weight.  Unless there is a
>> serious risk to using trawl floats, I think they are the most  logical
>> and cost effective choice  at 3 dollars per lb of buoyancy .    I will
>> also have  substantial MBT  volume to offset failed trawl floats.    If
>> I am wrong, please correct me, I would love to have steel tanks,  that
>> is right up my alley.
>> Hank