ortho-Iso-Vinyl,,a comparison of resins....

[seamonkey]

I'm trying to establish the price/strength/weight comparison between these 3 resins.--the product focus is a 24' sportboat racing sailboat,,where strength/weight is definetly a priority,,but of course,,$ are part of the equation.
So far ,it seems to me for the reletivly small difference in price,that it's a no-brainer to at least use ISO resin for the lessened degree of shrinkage which is widely acknowledged,,,but few people I've talked with regard vinyl-esther to be enough of a structural improvement to justify it's extra cost.
Personally,,I've used vinyl and iso/vinyl blends extensively in high performance sailboat -repairs-,,and have considered vinyl to be superior not only for osmosis supression,,,but also in it's resilience , shrinkage and bonding factors,,hence it's better strength/weight ratio is a good solid step towards using epoxy.---am I wrong??..........thanks.

[tja]

I think that you have answered your own question, but here goes. You will have more shrink with iso then the other two resins. Go with a vinyl ester blend. I personally prefer Hydrex. Good luck, Tom.

[seamonkey]

thanks tom,,I was kinda thinking I had a handle on the information,,but it's a jungle out there,,and I'm in between a build company,,,,supply reps,,,,and the guy paying the bills,,trying to mediate the most effective approach through all the interests.---you'd be surprised that the supply rep was advocating ortho resin even as the best choice for strength/weight,let alone cost.

Do you know where I might find a technical comparison of the properties between ortho/Iso/vinyl/...and blends??.....thanks!!

[Herman]

Ask for datasheets from your supplier. There is some data on it about strength, elongation and glass transition temperature. Then you will quickly find out...

[D'ARTOIS]

Vinylester is far more superior to ortho and iso, as already said, you answered your own question - .

[JR-Shine]

I second the vinyester vote.

[rxcomposite]

Dont use ortho. It is cheap but it is also brittle. Iso is the best all around choice. Vynil or Iso Vynil is best. It is also the most expensive. Ive seen boatbuilders layup the outer wet side resin rich layer with vynil then proceeded with iso resin on the succeeding layers to save cost. I do not know the long term effect of the bonding between iso and vynil.

What i do know is that you can bond epoxy to any iso or ortho laminate but you cannot bond iso or ortho to an epoxy based laminate. So once you repaired the hull with an epoxy resin, you cannot re-lay it up with iso/ ortho. You have to remove the epoxy first.

[Vanbokklen]

Originally Posted by tja

You will have more shrink with iso then the other two resins.

Sorry but this is wrong information. Iso is typically tooling resin which is shrinks less than Ortho.

[Herman]

I think the topicstarter was comparing ISO against vinylester and epoxy. In that case the topicstarter is right.

[Danielsan]

My idea, Seamonkey,

Get the best quality (vinyl) if you are going for the weight and good specs. I have to recalculate because i lost some things on a computer crash this WE.
But I found out that if you do a ordinary handlayup in glass or if you would make sandwich constr it is an higher cost of about 80% (1000 instead of 1800)

If you use worst to best it will be 15% more coslty (compared glass layup and glass layup) (compare sandwich and sandwich)

(so ISO + core + Iso) < (Iso + better core + Iso) < (vinyl + core + vinyl) < (vinyl + better core + vinyl)
common better better best

Upon the size of your boat +80% +15% can be acceptable or huge :-)

Some with exp. correct me if I am wrong, so me and other dont follow foolish things

Daniel

[jfblouin]

Danielsan

Can you detail the cost of with and without core.

I study core application (for small boat whitout weight problems) and maybe I wrong or I don't find a good supplier for core but I dont find a big difference in cost between the two methods.

Like I probably use female mold for my project, I find that a good laying core is difficult to reach.

[ErikG]

jfblouin

SP Systems makes their SAN core in Canada... maybe you could buy factory direct?

[jfblouin]

Very Interresting

I find their WEB site so I will continue in this side

Thanks

[Danielsan]

JFblouin,

attached you can find some excel sheets I made last night.

I based it upon data RXCompite gave me, I have to change according new data he gave me today.

I used this for the price calc of the sandwich construction.

If you dont use Core material you will have to add some layers of glass see coloured numbers and leave the core at 0,00.

I made this for my own purpose so I know what I put in the sheet. If you need more info, just ask me.


Greetz

Oh hell! I put the no sandwich sheets in it too. You can play with the numbers yourself as I am not sure about the glass layup for non sandwich.

[rxcomposite]

Jfblouin,
A cored boat will always be lighter but not necessarily cheaper. If you can get cheap core in your area, then you are in the winning side. Shipping core is like shipping air. Lots of volume but no weight. On our side, core is very expensive because of shipping.

Rx