Epoxy versus vinyl ester

[rxcomposite]

Originally Posted by apex1

There is NO increase Mike and Rx!!!


The composite does just not behave as we want it to do! ****..

Why do you lose your cool over studies presented by refutable institutions. Why, even personalities were not mentioned. Unless that "****" refers to me and Mike? Then that becomes personal.

Originally Posted by rxcomposite

Why, even personalities were not mentioned. Unless that "****" refers to me and Mike? Then that becomes personal.

Of course not!

[rwatson]

Originally Posted by rxcomposite

Why do you lose your cool over studies presented by refutable institutions. Why, even personalities were not mentioned. Unless that "****" refers to me and Mike? Then that becomes personal.

I dont think Apex was being personal, for what its worth I read it as being "**** - we cant do anything about it"

This written word can be so easily mis-intepreted though, thats for sure.

It pays to clarify.

[War Whoop]

Originally Posted by rxcomposite

Marine Composites by Eric Greene and Associates have long stated that "Some advantages of the vynil esters, which may justify their higher cost, include superior corrosion resistant, hydrolytic stability, and excellent physical properties such as impact and and fatigue resistance. It has been shown that a 20 to 60 mil inner layer with a vynil ester resin matrix can provide an excellent permeation barrier to resist blistering in matrix laminate."

Professional Boatbuilder magazine also ran an article about "blistering" some many years back. The article reccomends a vynilester resin matrix on the initial (after gelcoat) laminate.

Vynil ester drawback is its low Barcoll hardness reading and high elongation, hence it did not became popular to use "vynil ester only" on the whole boat.

Depends on the resin there are some with good barcol and @5% elongation which is what one would want for a survivable boat, a example would be the old Dow 470-36 with excellent chemical and physical characteristics which was my base resin system for years.

Originally Posted by War Whoop

Depends on the resin there are some with good barcol and @5% elongation which is what one would want for a survivable boat, a example would be the old Dow 470-36 with excellent chemical and physical characteristics which was my base resin system for years.

5% is a hell of a lot.

After 1200 tonnes (structural weight) of craft produced (was only 5 boats) we give up on VE processing.
It was nearly a death trap!

A proper investment in skilled labour on carbon prepreg, would have saved me money, time, and some disgusting experience, how VE **** deteriorates even while processing it!

Forget about VE!

Regards
Richard

edit:
well, should have said:
we were the "new boys on the block", having processed wood Ep for over 30 years, but "ester" is not what one single worker on my shopfloor wants to handle! So, we go CF for the bigger thingies...

[War Whoop]

Originally Posted by apex1

5% is a hell of a lot.

After 1200 tonnes (structural weight) of craft produced (was only 5 boats) we give up on VE processing.
It was nearly a death trap!

A proper investment in skilled labour on carbon prepreg, would have saved me money, time, and some disgusting experience, how VE **** deteriorates even while processing it!

Forget about VE!

Regards
Richard

edit:
well, should have said:
we were the "new boys on the block", having processed wood Ep for over 30 years, but "ester" is not what one single worker on my shopfloor wants to handle! So, we go CF for the bigger thingies...

LOL NO 5% is about perfect Also Here is a 488 KG Hull and deck 11 Meter Offshore boat of mine in done in Dow VE some 20 years ago, I can do better nowadays, BTW you talk to much,it depends on the customer they want to spring for the epoxy then fine but in this economy the VE will win ,I build One off foam core.

http://www.youtube.com/watch?v=h1csGLgX4tk

[rxcomposite]

Originally Posted by War Whoop

LOL NO 5% is about perfect Also Here is a 488 KG Hull and deck 11 Meter Offshore boat of mine in done in Dow VE some 20 years ago, I can do better nowadays,_the VE will win ,I build One off foam core.

http://www.youtube.com/watch?v=h1csGLgX4tk

Right on the money. When designing for impact strength, VE is better that poly and epoxy

High density foam core is better than honeycomb or balsa.

The material property is always chosen by the designer to satisfy the operating condition. Of course, cost is also a factor.