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Dr. Eagle
06-18-2004, 11:29 AM
I hear about doing this to gel coat and paint, but what are the steps and processes to do it properly?
Now that I have the stereo and electrical just about wrapped up in the boat, and I am getting all the mechanical to-dos done today... the next thing I have to do is get the gelcoat cleaned up.
It looks very good, but the first owner of the boat painted a name on the transom. When the name was removed it was a different color underneath than the surrounding gelcoat. Either the rest of the gel is UV worn a bit or the paint reacted with the still curing gelcoat.
Regardless, I want to try to get the color as uniform as possible, how do you go about that?

Wally_Gator
06-18-2004, 11:35 AM
Very carefully,
First you will need 600 grit or even 1,000 grit wet/dry sandpaper.
Then you will Sand the area around with the sandpaper wet. Keep it wet but not too we or too dry. You should feel the sandpaper cut into the gel coat and you will see (with white) milky white water.
Use a sanding block on flay surfaces and don't concentrate too much on one spot as you can burn through the gel coat.
I would start with 600 and then go to 1,000 in your case.
After sanding you will need a good rubbing compound for fiberglass and a polisher with a wool bonnet.
Work small areas and work the compound with pressure over a 2' area until the compound completely breaks down and you see a good shine. Do not work in one spot as you can burn the gel and discolor it. Keep the polisher moving.
I hope this helps.

Dr. Eagle
06-18-2004, 11:37 AM
Thanks, I wasn't sure what grit wet/dry to start with for one thing. I appreciate your help.:D

HalletDave
06-18-2004, 11:38 AM
Keep the polisher around 1,800 RPM.

Wally_Gator
06-18-2004, 11:43 AM
Another thing...
The discoloration is probably the gel that was not covered by the paint. UV does that to the Gel. Be careful and you may be able to fade the discoloration around the painted spot.
You may want to have a beer or stiff drink around for the first time you take sandpaper to your hull. It is one hard first step.
But once you start you are committed.

Jbb
06-18-2004, 12:12 PM
Everyone has there own preferences .....these are mine..
If a light sand/ buff is what is needed due to some dulling due to perhaps wax buildup...first,wash whatever your buffing till its spotless...any grains of dirt under your sandpaper will leave a scratch thats very difficult to remove...
after its clean...wet sand with 1500 grit wet paper...3m is my favorite...hint...let the sandpaper soak in a CLEAN bucket of water with a drop or two of detergent for 15 min.before you start..
sand with 1500 grit...on a soft rubber sanding block till the dullness is uniform...you will know it when you see it....I then go over the area with 2000 grit in the opposite direction...wash again then buff....I use about 1500-1800 rpm with a white foam pad....I use wool only when I need to use a real agressive compound...I use 3m Finesse it 2 compound ...when thats done...wash again and use the black foam pad and glaze with 3m finese it 2 glaze...this is what removes the swirl marks...wash again...apply a coat of your favorite wax or polish..I have been using Collenites Insulator wax lately and I like it...See this thread for some info on buffing paint...
Buff it! (http://www.riverratlife.com/forums/board/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=21;t=000006)

HCS
06-18-2004, 12:17 PM
I got some paper at home. Look me up and I'll come over and we'll sand your boat down.
Just becareful if you use a buffer. You can burn the gel coat.
That can get ugly.:)

HCS
06-18-2004, 12:25 PM
Iv'e sanded and buffed out some real bad scratches.
To my own suprise it came out great. If I remember
right like everyone else I used 1000 grit then buff lightly,
then use 1500 grit and buff again. Then hand polish.

HalletDave
06-18-2004, 12:26 PM
Originally posted by HARDCORE-SKI
I got some paper at home. Look me up and I'll come over and we'll sand your boat down.
Just becareful if you use a buffer. You can burn the gel coat.
That can get ugly.:)
Less chance of burn streaks if you do like Brian said, keep the buffer between 1,500 & 1,800 RPM.
Don't use hard down pressure on the buffer. Let the compound do it's job.
I have had good results using this technique.
The old '77 Hallett won the Best Original Gelcoat Award at 2003 CBBB.;)

Wally_Gator
06-18-2004, 01:04 PM
It also depends on the compound.
Some more agressive compounds won't break down without pressure. These compounds in the right hands break down to produce a finer polish that some of the more mild compounds.
A heavier compound without enough pressure will result in a poor polish.
Not that anyone should be pushing on it like a gorilla.

HalletDave
06-18-2004, 01:14 PM
Originally posted by Wally_Gator
It also depends on the compound.
Some more agressive compounds won't break down without pressure. These compounds in the right hands break down to produce a finer polish that some of the more mild compounds.
A heavier compound without enough pressure will result in a poor polish.
Not that anyone should be pushing on it like a gorilla.
WG,
Exactly, the "gorilla" part is what I was referring to.:D
The 3M compound I use works well with just the weight of the buffer.

Essex502
06-21-2004, 06:41 AM
Where can you can the 1000, 1500 and 2000 grit sandpaper for these kinds of jobs?

MudPumper
06-21-2004, 06:47 AM
Essex, there is an auto body supply store on San Fernando road in between the 14 and where the railroad tracks cross near Hart Park. Its on the South side of the street across from the plumbing supply store. They will have everything you will need.

HCS
06-21-2004, 07:18 AM
Originally posted by Essex502
Where can you can the 1000, 1500 and 2000 grit sandpaper for these kinds of jobs?
Some of your local auto parts stores have it or can get it.
Napa, Kragens.

nodigg
06-21-2004, 07:35 AM
I just removed the name from the back of my boat after 6 years and had the same dis-coloration you speak of. 1200 grit and buffing not only removed the difference but I was amazed at how bright it made the gelcoat look. (Had to do the whole boat then).

Dr. Eagle
06-21-2004, 07:46 AM
Originally posted by nodigg
(Had to do the whole boat then).
That is what I am expecting. I suspect that I will clean the back up and have to do the whole thing...;) The yellowing is especially obvious on the white gelcoat. Bummer is you have to take the hardware/rails/windshields off to do it right...

HCS
06-21-2004, 08:05 AM
I had to sand around my rear hand rail unless I was going to remove
the fuel tank. If you look real close your can see it. But you have to really
look hard.

Dr. Eagle
06-21-2004, 08:07 AM
Originally posted by HARDCORE-SKI
I had to sand around my rear hand rail unless I was going to remove
the fuel tank. If you look real close your can see it. But you have to really
look hard.
OK when I get home and get to Folsom, you'll have to show me:D

HCS
06-21-2004, 08:16 AM
Originally posted by Dr. Eagle
OK when I get home and get to Folsom, you'll have to show me:D
No problem.;) I let my brother put gas in my boat. He dropped the gas nozzle on the back of my boat and took a small chip out of the gel coat. To my amazement I was able to color sand it out.
Sanded, polished and buffed. Good as new.

Essex502
06-21-2004, 10:56 AM
Originally posted by MudPumper
Essex, there is an auto body supply store on San Fernando road in between the 14 and where the railroad tracks cross near Hart Park. Its on the South side of the street across from the plumbing supply store. They will have everything you will need.
Thanks MP...are you local to Santa Clarita?

MudPumper
06-21-2004, 03:23 PM
Born and raised!!!:D

JetBoatRich
06-21-2004, 04:19 PM
Originally posted by HARDCORE-SKI
No problem.;) I let my brother put gas in my boat. He dropped the gas nozzle on the back of my boat and took a small chip out of the gel coat. To my amazement I was able to color sand it out.
Sanded, polished and buffed. Good as new.
I will bring my boat up and you can knock it out for me during the week;) How about I drop it off on Monday and Pick it up Thursday night:eek:

Essex502
06-22-2004, 06:25 AM
Originally posted by MudPumper
Born and raised!!!:D
Can't claim I go back that far...moved to SCV in 1991 will be leaving when we can support our lifestyle fulltime in LHC!

MudPumper
06-22-2004, 10:00 AM
I hear ya, this place is getting damn crowded. I remember when Soledad from Canyon Country to Valencia only had about 5 stop lights. I think there are about 30 now.