Courtney Thomas wrote:
To Glenn:
1-My original post was regarding EPOXY resin, not polyester.
Sorry. Your original post that I replied to concerned polyester. You
did not make much distinction about the change of resins in your second
thread.
2-If I understand you, all I've read says..... the opposite of your
contention, i.e. that E-glass is best. S-glass is way stronger than
E-glass.
S-glass is considerably stronger than E-glass but the price does not
justify the difference.
3-Again, I'm not talking about your suggestion of multiple layers, but
rather a compound 'mat' having all three of the triaxial layers in one
layup.
YOu need to be concerned with the learning curve and getting the team
adjusted to working together. I'll give you an idea of how our lay-up
went. We had two layers of uni-directional to be laid at 45º either way
from vertical to lay. We laid 3 runs of the first layer and then the
first run of the second. Then we kept the first layer two runs ahead of
the second. The first 20' took about 4 hours with one person mixing
resin, two wetting out and 3 or 4 laying. The last 25' took about 2
hours because we all got the hang of it and refined the process.
Triaxial will be a lot harder to wet out and handle. While you will
have less than half as much yardage to lay I would not expect that you
will be able to do it in much more than a couple of hours less.
4-I've said nothing about the cost of epoxy in my posting. I don't know
to what you are referring here.
You were talking polyester 24 hours before.
5-I can't think about a smaller boat 'cause I'm talking about
relaminating an existing one.
You are asking for trouble.
Apparently I did a foul job in my original post.
Yes.
Thanks for input on this matter from all readers !
Courtney
Glenn Ashmore wrote:
Did you read my post in the original thread? You will never have
enough time to bag a 40' hull with polyester. You do not have enough
open time. Epoxy and properly aligned uni and bidirectiona E-glass
will be stronger, lighter and give plenty of time for a crew of 6
people to lay two plys on a 40' hull. We were very well organized
with all the right tools when we bagged my 45' hull and it still took
6 hours to lay the glass and another hour to set the peelply,breather
and bag and another 30 minutes pull the bag. Polyester will give you
two hours at most IF you can control the catalyst very closely and
keep the temperature in the low 60s.
If you are worried about the extra cost of epoxy you better start
thinking about a smaller boat because what you will save with
polyester on the hull glass is an infinitesimally small part of what
you are about to spend.
Courtney Thomas,,, wrote:
John,
Thank you for your reply, but you are repeating my questions :-)
The hull is 40' LOA.
No I don't have any experience doing this....that's why I'm posting
the query.
I'm confused as to why you are unclear of the motive, ostensibly
knowing the difference between E-glass/polyester resin and
S-glass/epoxy.
Anyway, have you any related experience/knowledge of such an
undertaking ?
Cordially,
Courtney
John Meachen wrote:
There is no technical reason why it cannot be done.There is however
a need for enough people to cope with the job.It would be useful to
know how big the hull in question is.
Ther is also the question of why you would mix E-glass and
polyester with S-glass and epoxy.Have you any experience of either
combination?
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at:
http://www.rutuonline.com
Shameless Commercial Division:
http://www.spade-anchor-us.com