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View Full Version : How to get rid of scratches and scrapes on side of boat??


bfinley
09-24-2004, 04:13 PM
I bought a 1992 Prostart this spring. It's been a great boat, but I'd like to take care of some of the scratches on it. What's the best way to get rid of these or make them less visible??

SkySkiSpokane
09-24-2004, 04:30 PM
I haven't had to deal with anything too deep but for the small stuff and the scuffs, this 3M marine stuff is really good!
http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10001&productId=72492

ski_king
09-24-2004, 04:36 PM
Hey SkySkiSpokane, nice Avatar!

How about the full size picture of that on the faceplant thread?

MarkP
09-24-2004, 06:10 PM
Bfin

Just out of curiosity, What color is your 205?

ShawnE
09-24-2004, 08:45 PM
Bfin
I also bought a '92 205 this spring. pics in the profile.
How do you like it?

MarkL
09-24-2004, 10:28 PM
Depends on how deep the scratches are. If they're not very deep wet sand with 400 then 600 then 800, then 1000, then 1500,then compound and polish. Be careful, gel coat is only so thick and you don't want to sand through to the glass. You can fill deep scratches with gel coat available at West Marine or Boater's World. Gel coat will not cure exposed to air so cover with cellophane tape or polyvinyl alchohol (also at WM or BW). Sand as above after cure of gelcoat.

JimN
09-24-2004, 11:51 PM
If gelcoat doesn't cure when it's exposed to air, how does it cure when it's sprayed on by so many boat manufacturers?

H20skeefreek
09-25-2004, 08:16 AM
If gelcoat doesn't cure when it's exposed to air, how does it cure when it's sprayed on by so many boat manufacturers?


Jim, they use the PVC mold release first, then the gel, it will cure, but not completely. They are then laying/spraying the glass over it, which allows it to cure completely and form a chemical bond between the glass and gel.

JimN
09-25-2004, 08:53 AM
I'm not talking about MC. On most other boats, the fiberglass is layed up in the mold and the gel is sprayed over that, then they sand and polish it to get the best finish they can. Spraying the mold before laying up the glass is the exception to the rule. Gelcoat also cures from the outside in, from what I was told be someone who has a fiberglass/gelcoat repair shop.

stevo137
09-25-2004, 09:39 AM
I have had good results with Meguiars no 49 Heavy Duty Oxidation and scratch remover, about $11 a bottle. I used a random orbit action polisher. DO NOT CHEAP OUT A BUY A CHEAP BUFFING PAD! Buy the wool pad for about $12. It won't wear out on the edges. If it wears out on the edges and the buffer jumps, you could make a worse scratch than you already have.
One time for a deep scratch on my 88' I used the Meguiars right on a 2400 and then a 3600 Micro Mesh sandpaper and rubbed by hand until the scratch was gone. After that I did a final buff with the polisher. It worked great.
There will some areas that you can only do by hand but this product also works good just using it without a buffer.

H20skeefreek
09-25-2004, 10:23 AM
I'm not talking about MC. On most other boats, the fiberglass is layed up in the mold and the gel is sprayed over that, then they sand and polish it to get the best finish they can. Spraying the mold before laying up the glass is the exception to the rule. Gelcoat also cures from the outside in, from what I was told be someone who has a fiberglass/gelcoat repair shop.


it's not that uncommon to shoot the gel first, but in a situation where the glass is laid first, then a gel over it, the gel has to be covered with a PVC gel or some type of mylar film. The gel will partially cure, but not to a hard, sandable finish, with exposure to the air. You can call spectrum and ask if you'd like. I've spoken to them before.

JimN
09-25-2004, 10:24 AM
The biggest thing about getting rid of scratches and scrapes is, BE PATIENT! Use the mildest abrasive you can. If it's a deep and/or wide gouge, use a gelcoat repair kit. You don't want to feather a deep scratch because you would need to remove too much gelcoat for it to not turn into a big job. Gelcoat isn't very thick. Too thick and it tends to crack, too thin and it shows the fiberglass and won't last very long. If you see the glass underneath, you definitely need to fill it in before levelling it.

H20- the first MC dealer I worked for had a 'glass/gelcoat repair shop onsitewhich is the only kind of work they did) and I was there when they did repairs as well as after it had cured. It was hard, not gummy or soft. They put heat lamps near it unless it was summer. I don't remember them putting any sheeting or gel over it. I also used Spectrum gelcoat repair kits a lot. Like I mentioned, it sets up from the outside first, so that probably helps in the curing process.

I wasn't aware that many boat makers sprayed the gelcoat into the molds before laying up the glass. I don't remember any others making a point of it and have talked to the other manufacturers whose boats we sold, about their processes. They all said they spray the hull after it comes out of the mold.

bfinley
09-25-2004, 11:13 AM
Here's a picture. It's been a great boat for me.

JimN
09-25-2004, 11:40 AM
H20- does West Marine sell an adhesive called Plexus? It's similar to 3M's System 2000- 2 part with the single nozzle that mixes internally, with a gun that holds the double tubes and has two rams.

H20skeefreek
09-25-2004, 12:29 PM
H20- does West Marine sell an adhesive called Plexus? It's similar to 3M's System 2000- 2 part with the single nozzle that mixes internally, with a gun that holds the double tubes and has two rams.


hmmmm...... the only plexus i know of is a plexi-glass/lexan window cleaner. we do sell that. and we sell the 3m system you are speaking of, but don't recognize that name as an adhesive.

MC was definatly one of the first to shoot the gelcoat first, but many have immitated the process from my understanding. it's a much better way to do it for several reasons. 1. you get a smoother gel, which makes the finishing easier and 2. you can apply the glass earlier in the curing process, which makes a better chemical bond between the layers.

I'm wondering when a ski boat manufacturer will go to a plastic outer skin layer similar to what's used on many Genmar boats. It seems to be an interesting alternative.
http://www.genmar.com/page.cfm?id=91

H20skeefreek
09-25-2004, 12:32 PM
Jim, on genmar's website I also found this. It refers to the typical layup process, as if it's the norm.

http://www.genmar.com/page.cfm?id=40

MarkP
09-25-2004, 02:16 PM
Bfin

I have a scratch that I want to fix on my boat. Unfortunately, the 15.00 “kit” is not available for my color anymore, just the 65.00 quart can of gel. (6 mo shelf life). It looks like we have the same color “blue Atlantic” So if you need to repair any gel, maybe we could split a can..

http://www.spectrumcolor.com/catalog.htm

MarkP
09-25-2004, 02:19 PM
Bfin

I was just looking at the Spectrum product catalog and your 92 is probably the “flagship blue”, Never mind :o

JimN
09-25-2004, 02:34 PM
Genmar's process does sound interesting and I have seen articles about it since the late '90's. I think they went to this type of molding to save a lot of money but I think they are more easily able to absorb the development costs because of the size of the corporation, as opposed to a company that makes 2000-3000 boats per year.

Jorski
09-27-2004, 10:01 AM
Virtually every boat made is built from the outside in...spraying gelcoat into the mold.

Cheap boats spray the glass with a chopper gun, this is where savings can be made. Well built boats hand lay the glass which is time consuming and therefore expensive. The result is that there is a better glass to resin ratio which is stronger and lighter.

In fact I have never heard of a manufacturer (no matter how small) applying gel after the boat is built. I have been to dozens of plants.

LakeLottawatta
09-27-2004, 11:23 AM
To get rid of scratches:
1.)Wet sand with 1200-1500 grit (or lower depending on depth of scratch)
- things to remember with wet sanding: Soak your sand paper overnight! also, add a small amount of liquid dish soap to your water, use a squeege to clear the water/grit so that you get a good look in between rinsing your paper.

2.) Buff with 3M "High Gloss Gel Coat Compound" using a variable speed buffer with 3M SBS pads. Makita makes a variable speed buffer (model #9227) that has a governer in it that regulates speed and maintains a constant speed no matter what! It is the buffer the pros use. The cheapies from Harbor Freight are more likely to burn right through the gel coat and into the mat in the hands of the inexperienced user.

3.) Polish with 3M "Perfect-It Foam Pad Glaze #05937"

4.) Sit back and enjoy the highest gloss, best looking Gel coat on the lake.