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formulaben

The 3M Super Duty Compound is the equivalent to 1000 grit sandpaper.  I used it with the wool pad after wet sanding and worked my way up to regular compound, finesse it, then fine polish.

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DevonEhrhardt

Finally had a nice day of sun here in Vancouver, so thought I might start working on doing my boat. Boat's gel was in bad shape, pretty heavily oxidized. having done a pass at 400, 800, 1200, and 2000, is it normal for the gel to look almost the same as it did previously? Additionally, im noticing some minuscule black dots appearing in the gel coat. Would that be the real colour underneath, or am I simply going too deep with my sanding? Sorry if im hijacking the thread a bit

 

 

20180310_110157_resized.thumb.jpg.a1d904ef0edff3c1bfdb3e9ddb797908.jpg

Area within the box is the sanded are

Inked20180310_153300_resized_LI.thumb.jpg.b6d8b0fc7edce9d52fb727c21528ed85.jpg

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MadMan
1 hour ago, DevonEhrhardt said:

Finally had a nice day of sun here in Vancouver, so thought I might start working on doing my boat. Boat's gel was in bad shape, pretty heavily oxidized. having done a pass at 400, 800, 1200, and 2000, is it normal for the gel to look almost the same as it did previously? Additionally, im noticing some minuscule black dots appearing in the gel coat. Would that be the real colour underneath, or am I simply going too deep with my sanding? Sorry if im hijacking the thread a bit

 

Area within the box is the sanded are

 

I would say you didn't sand anywhere near long enough with the 400.  I started with 320 and wet sanded until the material being removed was the base color, black in your case.  As long as it's white, you're still getting through the oxidation.

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formulaben

Are you dry or wet sanding?

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carguy79ta
17 hours ago, MadMan said:

I would say you didn't sand anywhere near long enough with the 400.  I started with 320 and wet sanded until the material being removed was the base color, black in your case.  As long as it's white, you're still getting through the oxidation.

yup...wut he sed..

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DevonEhrhardt
12 hours ago, formulaben said:

Are you dry or wet sanding?

Definitely wet sanding it

On 3/10/2018 at 5:25 PM, MadMan said:

I would say you didn't sand anywhere near long enough with the 400.  I started with 320 and wet sanded until the material being removed was the base color, black in your case.  As long as it's white, you're still getting through the oxidation.

9 hours ago, carguy79ta said:

yup...wut he sed..

Thats what I thought was likely the case, but my dad was adamant that I was was going too rough on it. Nothing like two people with differing opinions working on a project like this.

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saxton15

You definitely have more oxidization to get off.  Keep going until the sandpaper is coming off black.  Then gradually move up in grit.  Use a cut compound to bring the shine back.

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MadMan
6 hours ago, DevonEhrhardt said:

Definitely wet sanding it

Thats what I thought was likely the case, but my dad was adamant that I was was going too rough on it. Nothing like two people with differing opinions working on a project like this.

Just to ease your mind, the thickness of the gelcoat on your boat is about 10 times the .002" or .003" the clear coat of your car. 

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carguy79ta

isn' gel coat about 1/16inch?  (.0625")

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boardjnky4

i doubt you'll ever be able to wet sand all the way through the gelcoat. It's REALLY thick.

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carguy79ta
25 minutes ago, boardjnky4 said:

i doubt you'll ever be able to wet sand all the way through the gelcoat. It's REALLY thick.

that's what I was thinking

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boardjnky4

When I wetsanded my A22 (which is Red), it looked like a literal blood bath.

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wbama387
Posted (edited)

It would take a lot of sanding to wet sand through the gelcoat completely, but you can easily sand through colors. They are sprayed with a base color and the rest of the colors are sprayed on top and they are much thinner. A lot easier to sand through. Trust me I am dealing with this on my brand new boat.

Edited by wbama387

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wbama387

I personally would not do anything coarser than 800 grit and step up from there.

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carguy79ta
34 minutes ago, wbama387 said:

It would take a lot of sanding to wet sand through the gelcoat completely, but you can easily sand through colors. They are sprayed with a base color and the rest of the colors are sprayed on top and they are much thinner. A lot easier to sand through. Trust me I am dealing with this on my brand new boat.

I am thinking that the older boats are the ones that have the heavy oxidation, requiring sanding.  they are prolly solid color all the way thru. the new boats shouldnt require sanding, since no oxy.  what happened to yours? didn't know about thin color and cleargel buildup. makes sense.

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wbama387

My boat is a base color of vapor blue and there are low spots of black where the blue is showing through. They are working on correcting this, but even in other spots it doesn't take much wet sanding to sand completely through the black to the blue.

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carguy79ta

holy moly!!! wowzers!! would have never guessed.  glad the dealer is stepping up.  let us know how it works out, pics would be great.  a lot of us have new boats, something to be aware of.

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Pnwrider

Why are you wet sanding a brand new boat?

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wbama387

The gelcoat had to be cut out and new gelcoat filled in where the blue was showing through. My dealer had been great about it and is making sure it looks perfect like it should!

25951403937_9ba5ffa017_k.jpgUntitled by William Bru, on Flickr

40822777861_528a127486_k.jpgUntitled by William Bru, on Flickr

39928126385_6eda9afdc2_k.jpgUntitled by William Bru, on Flickr

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Michigan boarder
On 3/10/2018 at 6:49 PM, DevonEhrhardt said:

Finally had a nice day of sun here in Vancouver, so thought I might start working on doing my boat. Boat's gel was in bad shape, pretty heavily oxidized. having done a pass at 400, 800, 1200, and 2000, is it normal for the gel to look almost the same as it did previously? Additionally, im noticing some minuscule black dots appearing in the gel coat. Would that be the real colour underneath, or am I simply going too deep with my sanding? Sorry if im hijacking the thread a bit

 

 

20180310_110157_resized.thumb.jpg.a1d904ef0edff3c1bfdb3e9ddb797908.jpg

Area within the box is the sanded are

Inked20180310_153300_resized_LI.thumb.jpg.b6d8b0fc7edce9d52fb727c21528ed85.jpg

I agree with the others, keep sanding.  You need to be really patient with this process, your boat looks similar to how mine was, and you will likely need 40+ hours of sanding.  By the way, that hull looks dirty too, where the white appears.  You should acid wash the whole thing up to the rub rail first before much more sanding, so that you are taking the minerals off and any other residues.  That will save you a lot of time.  On mine, I acid washed the whole thing.  Then I did not sand any of the white, just the colors above the rub rail all the way around, the entire transom, and the colors below the transom from the stern to a few feet forward.  I buffed the rest and considered it good enough.  And that process took me 40 hours, so again - be patient, it is going to take some time.  Wet sand with a sanding block is a lot of work, but you will freak out once you start to see your colors pop again.

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Michigan boarder

Also - the miniscule black dots are the gel starting to come thru, that is progress.

Lastly - remove the transom eyes and grab rail, it will make your life much easier.

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Michigan boarder

post-8942-0-13373000-1427119405_thumb.jpgpost-8942-0-89962300-1427119265_thumb.jpg

I saved these pieces when enlarged the exhaust openings for STE's, so this was from the transom.  That white gel is pretty thick.

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