polyester vs vinylester resins

[sharkbait]

Does anyone know why Grady still uses polyester resins vs. vinylesters resins, which should be better at preventing blistering? :shock:

 

[gw204]

Cost.

I'm not sure about the cost of poly vs. vinyl, but I can tell you that poly is about 1/3 the cost of epoxy.

 

[sharkbait]

It would seems that if vinylester is better, Grady would step up and choose the better alternative. Since many view Grady as a quality boat, why skimp here?

 

[uncljohn]

its my understanding that they USED to make boats out of polyester resin, but that will absorb water, so now boat manufacturers use vinylester resin as that is not succeptable to water absorption.

I'm not sure when that change occurred, but I think it was in the mid-late 90s, so any new boat would only get blisters as a result of a manufacturing defect, but not from osmotic blistering as a result of sitting in the water w/o a barrier coat. While any boat built before 1990 could get blisters.

I can only assume that Grady has followed this.

 

[sharkbait]

I talked with someone at GW today, and they said they used a polyester blend that was similar to vinylester.