HELP - Gelcoat Repair Discoloration
09-06-2019, 06:50 PM
#1
HELP - Gelcoat Repair Discoloration
I mixed up some gel coat to fix some chips and holes around the boat. In every spot, when I go to sand the new gelcoat down, the old gel around the repair site discolors and turns almost orange. I'm wet sanding.
NONE of the instructional videos mentioned that this could happen. Any idea what I'm doing wrong or how to fix the discoloring now??
Thanks in Advance.
NONE of the instructional videos mentioned that this could happen. Any idea what I'm doing wrong or how to fix the discoloring now??
Thanks in Advance.
09-06-2019, 11:13 PM
#2
Admirals Club 
Keep in mind, the gelcoat is porous, and you may be sanding the surface, but perhaps there is still residue getting down in the gelcoat.
If it may be residue from the sand paper mixing with gel, you might try a scrub/wash with plenty of fresh water rinsing.
If that has no impact, I would wonder if you have some other type of residue showing up like a stain?
Believe it or not, sometimes a little Lysol toilet bowl cleaner can work wonders to clean gelcoat.
It may be worth trying if a good scrubbing and rinse won't take it off.
Good luck.
If it may be residue from the sand paper mixing with gel, you might try a scrub/wash with plenty of fresh water rinsing.
If that has no impact, I would wonder if you have some other type of residue showing up like a stain?
Believe it or not, sometimes a little Lysol toilet bowl cleaner can work wonders to clean gelcoat.
It may be worth trying if a good scrubbing and rinse won't take it off.
Good luck.
09-28-2019, 10:56 AM
#4
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you are likely bringing out the boats original color, what kind of boat is it? something thats an off white like a parker or grady white?
09-28-2019, 05:40 PM
#8
Admirals Club
Originally Posted by Bullshipper
Is the sand paper new, or was it used previously, contaminated with steel and now leaving iron that will rust when it reacts with the catalyst?
09-28-2019, 07:21 PM
#10
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I think he is seeing the original color. This is the reality of gelcoat repair.
Likes:
09-28-2019, 07:44 PM
#11
Senior Member
Originally Posted by Raybo Marine NY
I think he is seeing the original color. This is the reality of gelcoat repair.
I’m assuming he knows the original color, although this may be an incorrect thought.
He’s been back here today, but hasn’t offered any new information or updated anything.
09-28-2019, 07:54 PM
#12
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Original color meaning what you see when you start sanding it aggressive enough to bring it out
if sanded through I think he would be asking why he is seeing dark/black rings ?
if sanded through I think he would be asking why he is seeing dark/black rings ?
09-28-2019, 09:12 PM
#13
Senior Member
Yes, original color, not the faded and chalky color on the surface. I’m thinking he would know what color that was/is.
The underlining resin is typically an amber color, if light shines through it could appear orangish, although with no light it would appear dark.
It could also be a backup gel coat, overspray on the backside from a stripe, or a barrier coat.
For that matter it could be a painted boat and he’s seeing primer.
No way to know until he responds.
The underlining resin is typically an amber color, if light shines through it could appear orangish, although with no light it would appear dark.
It could also be a backup gel coat, overspray on the backside from a stripe, or a barrier coat.
For that matter it could be a painted boat and he’s seeing primer.
No way to know until he responds.
Last edited by ondarvr1; 09-28-2019 at 09:22 PM.
