Polyester Vs. Epoxy Resin

[swihartart]

Hello All,
I've cut a section of floor out of my 1977 Starcraft Capri. I got a sheet of PT plywood and want to glass it in to finish the job. I've read alot online and it seems to me that epoxy is definitely the way to go. I wanted to do the job this weekend so I called a local boat supplies store and the guy says I've got everything you need so I drive there and he pulls a gallon of resin (evercoat premium resin $87) off the shelf and a package of chop mat (50" x 3 yds. $36) and says this is the best you can use. I am covering 2' x 6' section.

I get the stuff home and pull the white cap off the resin container and notice some resin dried around the cap...

I open the cap and there's no seal and the resin is down about 1 - 2" below full...Hmmmm was some of this used or is this how it comes...and the can is somewhat beat up if that matters.

Now I'm really checking this deal out, inspecting the can I read it is Polyester...WTF is going on here, I told him that I wanted epoxy on the phone but failed to be sure when I bought it cause he was busy with another boat sale but pulled off of that even though I said I could wait....

Here's the question: Would I be crazy to use this stuff instead of returning it to him and waiting to have epoxy shipped to me stalling the project for a week or so? Will it do the job?

Something tells me when I take it back he'll say "this has been opened" I know...it came that way! Do they have seals from the factory or do they not, are they 1- 2" below full?

I kinda feel hosed but if this stuff will work it saves me 1 hour driving to argue with a guy about a return. I've thought about just cleaning the dried resin from around the spout and taking it back and just say it's not epoxy...the hardener is still sealed.

Any advice is greatly appreciated.
Sean

 

[Bob_VT]

Re: Polyester Vs. Epoxy Resin

Polyester resin will work fine and it is about 1/3rd to 1/4 the cost of epoxy.

Sad but some store owner's are confused on what is what.

Here is the true way to tell........ poly resin uses "drops" of hardener........ dries FAST! Epoxy uses a thick liquid hardener and it comes in a separate can and gives you a long time to relax ....... up to 6 hrs.

Your boat was built with polyester resin and has held up this long..... go poly and don't worry about it.

 

[Bifflefan]

Re: Polyester Vs. Epoxy Resin

I used only poly resin and have had no issues, (vise not adding enough hardener once). Its a great way to go and is easy to work with and sets up fast enough to sand in a couple hours if needed.

Sure you can use it and also get good results. If there is that much involved in the return id just use it. No need to add to an already trying situation.

By the way a gallon of Poly is about $31.00. Just FYI.

Throw up some pics of the work so we can see how its going.

 

[swihartart]

Re: Polyester Vs. Epoxy Resin

Thanks for the responses...I don't want any hate in my heart, I just wasn't sure if they come sealed or if they used some of this stuff and put it back on the shelf. They fix boats there also.

It's the principle when it comes to if they dipped into something that is sold as new...especially at $87 a gallon.

I could have got 3m Bondo polyester for $43 at the local hardware...is this just as good or is this evercoat premium just that much better.

My main concern is once I do this repair, some section of stringers are also being replaced, glue new carpet in I want to be good to go for many years.

thanks again and you're right Bob VT it's all about boating and having fun...that's why I bought the old girl.

It's all I could afford and knew with older toys, I could expect to fix things and being completely new to boating I've read the manuals, repaired everything else from trim system, rebuilt high output alternator, shift cables and interior upgrades, there was 1 small soft spot and it was right where the foam didn't reach by passenger right foot...so when I get this floor in...last step, kick *ss graphics in vinyl for the finishing touches and then after a year of fixin' her up, I get to chill on the water with my family and hopefully have several years of good trouble-free boating.

Have a great Memorial Day weekend...God bless our troops and Veterans everywhere.
Sean

 

[ondarvr]

Re: Polyester Vs. Epoxy Resin

Make sure the PT is dry before do any glass work on it.

 

[swihartart]

Re: Polyester Vs. Epoxy Resin

roger that, its been drying in the sun for 3 days, flipped twice a day and stood up at night in garage

 

[tallcanadian]

Re: Polyester Vs. Epoxy Resin

If you paid for epoxy then get the epoxy. I personally prefer epoxy for a number of reasons but the main reason for me is you have more working time with epoxy, there is virtually no smell to epoxy and over all it is stronger. But it is quite a bit more expensive than polyester. Your going to be spending enough money on your project, so don't go wasting it. Take the extra time and get the right stuff that you paid for. Good luck.

 

[83mulligan]

Re: Polyester Vs. Epoxy Resin

If you decide to use the polyester resin that is fine, however, I'd make sure you get compensated for their mistake. It sure looks like you paid epoxy price for the polyester resin.

 

[jonesg]

Re: Polyester Vs. Epoxy Resin

Steer clear of the hardware store polyester, it contains wax, you are much better off with the unwaxed resin.
Different websites favor different resins, we mostly use polyester because ....

real men don't care about the smell.

Evercoat is good stuff. Did you get the catalyst in the little tube?