Sanding/fairing fiberglass panels

[steveinak]

What type of discs do i use for my orbital sander to finish the panels i'm going to be laying up for my split house project. I see 3M has them in different colors(purple,gold,red)? guess that must be different grades of backing and what type of abrasive is on them ? What grit should i use ? I'm guessing 80 & 120 ?? I'd like to get the panels fairly smooth because the boat has a molded top and i'd like to keep it looking all the same.

 

[MDI45]

it kinda depends on the finish top coat you are going to use...gel coat or paint and will you be rolling it or spraying

 

[traditions]

Steve,What did you decide to use for material?If you could get some polyfair from a glass shop,and put it on with a sheet rock knife,and sand it out with some some gold 80 grit,it would take rolled on gel nice.Poly fair works good filling in mat and sands easy before it fully cures,make fiaring up qiute easy.

 

[steveinak]

it kinda depends on the finish top coat you are going to use...gel coat or paint and will you be rolling it or spraying

I'm going to use gelcote & rolling it on.

 

[steveinak]

Steve,What did you decide to use for material?If you could get some polyfair from a glass shop,and put it on with a sheet rock knife,and sand it out with some some gold 80 grit,it would take rolled on gel nice.Poly fair works good filling in mat and sands easy before it fully cures,make fiaring up qiute easy.

Still up in the air on the core material but i'm leaning towards the nidacore type stuff they have here. I'll ask about the polyfair stuff next time i get into town. I will be rolling on the gelcote top coat.

 

[traditions]

Steve,Polyfair comes in a 5 gal bucket,around $180.00.here.All you would need is a gallon or so.Nida core sheets are smooth,but you will have to glass them together.Have you ever heard of peelply?If you are just taping the edges together with mat you could use peelply to smooth up the mat finish,save a bunch of sanding.I dont know if you could buy it by the yard or not from your glass suplier.

 

[steveinak]

Steve,Polyfair comes in a 5 gal bucket,around $180.00.here.All you would need is a gallon or so.Nida core sheets are smooth,but you will have to glass them together.Have you ever heard of peelply?If you are just taping the edges together with mat you could use peelply to smooth up the mat finish,save a bunch of sanding.I dont know if you could buy it by the yard or not from your glass suplier.

I'll look into the peelply and the polyfair. Me & da wife get down to Seattle a couple of times every winter and i'm sure i can get anything i'll need when i'm down there. As always thanks for the advice.

 

[GoodChance]

Nidacore base, tabbed with 1700 or 1708 biaxle, then lots of epoxy mixed with microballons before the epoxy/biaxle kicks, sand with 120, and add several additional light coats of microballoons.

Admittedly this process I have outlined above is time consuming but strong and the right way.

 

[Blitzen]

Nidacore base, tabbed with 1700 or 1708 biaxle, then lots of epoxy mixed with microballons before the epoxy/biaxle kicks, sand with 120, and add several additional light coats of microballoons.

Admittedly this process I have outlined above is time consuming but strong and the right way.

If you choose to go this route just be aware that your polyester gelcoat will not stick that well to the epoxy base and may flake off over time.

 

[steveinak]

If you choose to go this route just be aware that your polyester gelcoat will not stick that well to the epoxy base and may flake off over time.

I won't be using epoxy because i don't have any experience using it.

 

[VPC]

top coat

I used nadia core was very happy with it, for a top coat I shot dupont marine imron excellent product, and for the decks i used delta polymers epoxy it's one of the best products for top coating a deck I did 4 boats with it all of which work and have gotten 3 yrs out of it.