Fixing The Hull quastion...

[LiPo Power]

...so I layed 3 small squares of fiberglass cloth on my hull using 30 min epoxy...
Now I need to send it out flat with 2-3 grades of sanding paper but everytime I get on it, the paper is getting stock with particles of epoxy and it is not sanding properly. Any suggestions on type of paper I should be using to smooth this out?
Any tips would be great...
Thank You
Robert

[monojeff]

You can try doing it wet with some light soap and use wet sand paper.
I am assuming this is on the outside of the hull??

[LiPo Power]

It is outside...

You can try doing it wet with some light soap and use wet sand paper.
I am assuming this is on the outside of the hull??

[monojeff]

That should do the trick for you.
The soap and water will rinse the paper while you sand and stop it from gumming up on you.
You just need a few drops of soap....

[LiPo Power]

What paper I should start with would you say?

[monojeff]

I'd say 320-400.
I'd rather sand longer then dig in to deep with courser paper JMO.
I like to put a towel down under the boat it helps to soak up some of the water and stop it from getting everywhere.

[Rumdog]

make sure the epoxy is fully cured also

[LiPo Power]

Small block of wood would be a good idea to sand flat areas I think.
So I just need to put few drops of water every little while to keep the paper wet not allowing the epoxy to get the sanding surface filled up with it...
Kool staff, thank you.
I will wait untill saturday with this making sure the epoxy is done for sure and after sanding I will paint it white with car paint in the spray can...

I'd say 320-400.
I'd rather sand longer then dig in to deep with courser paper JMO.
I like to put a towel down under the boat it helps to soak up some of the water and stop it from getting everywhere.

[monojeff]

Could also start with 220 but make sue it's wet sandpaper if you do.
Don't need to press to hard just let the paper do the trick.
I like to use a sponge and just squeeze the water on ther as needed to keep it wet.

[LiPo Power]

Ill squeeze the sponge to keep her wet all right!!!
Thanks for the tips and help.
I need to go to bed now but if someone has comments than please, post it, and Thank You...

Could also start with 220 but make sue it's wet sandpaper if you do.
Don't need to press to hard just let the paper do the trick.
I like to use a sponge and just squeeze the water on ther as needed to keep it wet.

[6sHyper]

sAnding works better than sEnding, lol. Sounds like your epoxy is not fully cured, also curious as to why you would use epoxy and not resin?? Resin dries harder and is easier to work with and better suited for that application IMO. With fiberglass resin i would start with 120 grit dry, then 180 , then 320, then primer, then 320-400-paint. I would not recommend using wetsand paper on any sort of filler, the only product that should ever be wetsanded should be primer or paint/clear. I'd like to think i know what i'm talking about on this matter since i am an autobody painter.

PS, for finishing work on top of the fiberglass cloth/resin you can buy marine finishing putty, which dries quick and sands and feathers beatifully! Available and canadian tire or local autoparts stores, heck probably even walmart. lol

[JackBlack26]

LMAO @ sAnding.....Epoxy will clog up the paper no matter what because like mentioned above, most epoxy, when fully cured, will stay a bit pliable. I have found that the more you sand it, the more heat builds up, and the softer it gets making it harder to sand. Resin is definitely the way to go!

[FloatDaBoat]

Can't Sand Epoxy Resin ???

Sanding is a process that requires FRICTION between two surfaces, which results in the creation of heat. Epoxy Resin will soften when subjected to heat. Dry sanding creates LOTS of HEAT, which results in the sandpaper becoming clogged-up.


WET sanding greatly reduces the amount of FRICTION & HEAT generated during the process. It requires much more time & patience to achieve satisfactory results, & should be done in steps.


Start by using 600 grit WET sandpaper, & use a finer grade for each subsequent step (i.e., 800, 1000, 1500, 2000), using LOTS of water. If too little water is used, the paper can still become clogged (rendering it useless), which also results in ruining the smooth, shiny, finished look. Besides, high quality wet/dry sandpaper is not inexpensive. Stay away from the cheap crap sold by places like Harbor Freight.


A properly sprayed finish produces the best results, but if one doesn't have the means to accomplish that, wet sanding can produce a decent looking appearance.


Here are a couple of pics showing the results of wet sanding down to 2,000 grit, when used on epoxy (3:1 mixing ratio) laminating/finishing resin, that was applied using a brush.

[LiPo Power]

Great help (also with gramma)...I hope I got them corrected all now... Thank You guys.
This is no big deal project. I have time so I will try sanding wet method ....
It is the left side of Stiletto after a hit by another boat.
Will let you know how it went.
I have 220, 320, 400 wet sanding paper, should be enough for this project...
Robert

[LiPo Power]

What is the resin you have good expierience with?
Thanks
Robert

sAnding works better than sEnding, lol. Sounds like your epoxy is not fully cured, also curious as to why you would use epoxy and not resin?? Resin dries harder and is easier to work with and better suited for that application IMO. With fiberglass resin i would start with 120 grit dry, then 180 , then 320, then primer, then 320-400-paint. I would not recommend using wetsand paper on any sort of filler, the only product that should ever be wetsanded should be primer or paint/clear. I'd like to think i know what i'm talking about on this matter since i am an autobody painter.

PS, for finishing work on top of the fiberglass cloth/resin you can buy marine finishing putty, which dries quick and sands and feathers beatifully! Available and canadian tire or local autoparts stores, heck probably even walmart. lol