Add resin to gel coats ?

[mokaa]

I add about 1.5 kg resin to 8k gel coat and add more pigment like 800g (color black) and spray it as flow coat then spry the pva . There's problem i will get in the future ?

 

[Woodonglass]

What are you trying to accomplish? I'm NOT a Gelcoat expert by any stretch but...

Adding Polyester resin to your Gelcoat mix is NOT gunna work. While Gelcoat uses Polyester as it's BASE it has additional chemicals in it. Adding more Polyester resin to it will really mess things up IMHO.

 

[ondarvr]

Like Wood said, it depends on what you expect to do with it.

Gel coat bases are typically ISO resins, laminating resin is normally a DCPD - ORTHO blend, there are other blends, but these are the lowest in cost and most common.

DCPD resins tend to weather poorly, can be rather rigid, to the point of being brittle, they also cure quite well even without wax being added to it, and don't shrink as much as other types. ORTHO's tend to be weaker, less water and weather resistant, more flexible and easy to work with.

Adding laminating resin to gel coat will lower the viscosity so it will flow better, Patchaid is made from the same base resin as gel coat and is added so gel coat can be sprayed more easily when doing repairs with smaller spray equipment. Adding laminating resin will work, but it may change some of the characteristics of the gel coat, but as a flow coat it should be OK.

Adding pigment back into it will help it weather better than without it.

 

[mokaa]

First, thx for your help Really i don't know what to do now, i spray my fishing boat 15m (hull only) with this way (resin to gel coats) my boat stay in water(salt water) for long long time (4-5) year. what should i do now ?! sanding the Hull again and spray it with gel coate only ! or keep it ,

 

[Woodonglass]

What Brand Name (MFG) of GelCoat did you use and what Brand Name of Resin did you ad to it? Did you thin it with any solvent and if so what solvent did you use?

 

[mokaa]

I use gel coat made in Taiwan 2740, same for Resin 2405, i add small amount of [SIZE=-1]styrene [/SIZE]to thin it, like 500g for total amount,

 

[jbcurt00]

What's the question?

You did the gel~resin blend 4 or 5 years ago, left it moored, and now you want to change the colors?

Is that gel mix failing in some way?

Now you want to know if you can re-spray it w/ a similar mix, just in different color, black?

Or do you want to use a similar mix to spray a different boat the same way and need to know if you can/should? And if there will be problems later?

 

[mokaa]

What's the question?

You did the gel~resin blend 4 or 5 years ago, left it moored, and now you want to change the colors?

Is that gel mix failing in some way?

Now you want to know if you can re-spray it w/ a similar mix, just in different color, black?

Or do you want to use a similar mix to spray a different boat the same way and need to know if you can/should? And if there will be problems later?

1-i Already spry my boat with this mix (gel&resin) "The question" there will be problems later ?!

 

[jbcurt00]

When did you spray it?

4 or 5 years ago, and it's been moored in saltwater since then?

I don't know as much about gelcoat as WoodOnGlass does, and not nearly as much as Ondarvr,but if it's been moored and over 4yrs, it seems to be holding.....

 

[mokaa]

I sprayed it from 1 month,

"The question" there will be problems later ?!

 

[jbcurt00]

Not sure anyone will be able to give you hard definitive Yes or No, lots of variables go into typical gel job. This wasn't typical.

Best I can do is maybe/maybe not, which is the same answer Ondarvr posted, if I'm following what he said.

 

[ondarvr]

My best guess, knowing nothing more than what has been stated so far, is that it will probably hold up OK. This is assuming you used the correct amount of catalyst, sprayed it correctly, and prepped the surface correctly.

 

[Woodonglass]

ondarvr IS our resident Gelcoat expert soooo I'd say that given the information he has to workwith, you should just let time pass and see what happens. As JBC says there's really no other definitive way for us to tell Way over here in America!!!! I wish you well!!!