Tailgunner wrote:
Brian Nystrom wrote:

Tailgunner wrote:

Anybody use this in a marine environment? How does it hold up?
I'm using it for a leaning post seat covered in vinyl.





Ethafoam is not closed-cell and depending on the density you use,
it can absorb quite a bit of water. The lower the density, the
more this is an issue. The 2# and to some degree the 4# density
are not well suited to a wet environment. The heavier 6# and 9#
densities don't absorb as much. The difference is due to the
smaller pores on the denser foams.




One last question if you don't mind. Can you suggest something for my
application?

I made a seat pan for the leaning post I'm building from a piece of
8" PVC that I cut lengthwise and flattened to form a 90. I used a
heat blanket and several cinder blocks to achieve this. It worked
like a charm. My plan was to glue the ethafoam to the pvc and then
wrap it in vinyl.


If the question is about gluing, it's very difficult to glue Ethafoam,
since it's polyethylene. In packaging, it's typically fused together
with heat (hot air or hot wire). If it fits the surface well, so that
there will be minimal tension in the glue joint, contact cement or an
adhesive/sealant like Lexel, 4200/5200 or one of the GOOP product
should do the job. If the foam must be bent to conform to the PVC,
you'll probably need some form of mechanical fastening in order to
keep it in place long-term. If you're wrapping it around a post, I
would suggest spiral wrapping it with tape before covering it with the
vinyl. This might actually be a "legitimate" use for duct tape. ;-)


Actually I was wondering what is a better foam to use. It sounds like
this ethafoam might turn into a sponge over time.

For the application you're contemplating, that's probably not the case,
but why take the chance? Something like Minicel foam would be a better
bet. It's microcellular, closed-cell polyethylene foam thats commonly
used for bulkheads, seats and padding in kayaks. It works well in wet
environments and although it's still polyethylene, it's much easier to
glue than Ethafoam, using the products mentioned above. It's also easy
to shape with Surform tools and sanders. If you want to see some
examples of it, you can peruse my Webshots albums on kayak outfitting at:

http://community.webshots.com/user/brian_nystrom-reg