Scratches in Gelcoat

[BobT]

As I am starting to sort "Escape" out for the winter her hull has a variety of scratches from lack of use of fenders and the like.  I've done some reading on line and the light "grazing" I have been able to rub out with some rubbing compound and elbow grease. Other slightly deeper scratches I have used  800, 1500, 2000 and 2500 grit wet and dry (wet) and then the rubbing compound with some success. However I am a little cautious as to how much sanding I can do without damaging the gelcoat and when a scratch needs to be filled rather than sanding/rubbing out. Some articles talk about if you can catch your nail in it then fill it but in my case that would be a lot of filling.  I have included some photos that try to capture the issue but I am not sure how clear they are. Experiences and views much appreciated.
Regards,
Bob

[Peter Cockerton]

Bob

That looks very extensive and way beyond what i have had limited success with gelcoat repair.
Being a  complete novice to repairing gelcoat i did ask Matt and he sent me a small amount of green gelcoat and activator. Like you i rubbed out light scratches with compound and deeper ones with wet and dry then compound. The deeper ones, (generally the white underlayer was showing through) i attempted to apply the gelcoat mix to and wait for it to cure, when it didn't cure i then found out you have to exclude the air from it with cling film. After curing i tried wet and dry to flatten it only to find the white started to show through again I i assume the repair thickness of gelcoat was to thin. So do you make the damage deeper and "v" shaped to allow more gelcoat in, I'm not sure. After several attempts i sort off hid the white and achieved a repair of sorts. The colour match was not perfect by the way, even though Matt supplied it and i used cutting past on surrounding area in case it had faded.

The two major sources of damage caused by 1) guiding the boat to the trailer whilst on a pontoon using bow and stern lines, the bow veered off at the last moment and hit the partially submerged end of the trailer where the retracted arms fit, nasty gouge right through gelcoat, very careful now when doing this. 2) Boat on the trailer at home, maneuvering trailer full of soil and hardcore past the boat, left wheel  of trailer hit a stone and the mudguard of trailer ran along the boat ( yes i was miffed ).

I use round fenders when against pontoon or wall, and the old covers supplied with the CF mast Matt purchases to protect the hull from the ratchet straps when trailering. One tip is to wrap the hook and webbing attached to the ratchet mechanism around the trailer chassis to shorten the length and the hook it back on itself this way the mechanism goes no where near the Hull.

Be interested in hearing how you get on with your repairs, i think you may need a professional hull refurb to bring it back to original though.

Peter

[Ged]

What I've done on my boats has been to fill the scratches where you can see the matting underneath, you need to carefully dig the scratches out a bit deeper and wider with a screwdriver and then fill with gel coat, you can get a wax additive which means you don't need to exclude the air.  I've found that deep scratches that don't go all the way through the gelcoat can be polished with an electric polisher (plenty of tutorials as to how to do this on you tube) it doesn't get rid of the scratch but it does polish it so you end up with a polished scratch which I've found to be acceptable most of the time, especially on a cruising boat, it's only a matter of time before it happens again anyway!
Even if you have the original gelcoat pigment the chances are that the hull colour will have faded and weathered so it won't be a perfect match.

[Simon Knight]

Hi,

I did quite a lot of repair of a Drascombe Coaster's Gel Coat  some time ago.  I started out quite timid but realised that Gel Coat is just like a thick paint and that mistakes can be corrected.  The major issue is getting a good colour match and opening up scratches to give the new material something to join to. 

As you have discovered if you use real Gel Coat it does not cure in air.  When the wax mentioned above is added I believe the result  is then known as Flo-Coat i.e. Gel Coat is 'best' repaired with Flo-Coat.  Just be prepared to do a lot of rubbing down with very fine wet and dry.

Good luck.

[Andy Dingle]

This company does GRP repair kits in just about any colour - RAL number colours, one of which should match the colour of your boat perfectly. There was a discussion thread on the forum previously - There is an item on the right RAL number for your boat on this website somewhere too.

http://www.ecfibreglasssupplies.co.uk/c-1041-gelcoat-repair-kits.aspx

They have a useful range of video guides on their website (all on you tube as well I understand) and are very happy to give advice on the phone.

Hope this helps.

Andy
BC23 Equinox (RAL 3005!)

[Rob Johnstone]

A word of caution - if your boat is more than a couple of years old, it is quite likely that new GelCoat of the right RAL number will not match to hull any more because the colour of the hull will have faded and even cutting it back with polish won't necessarily restore it to the original shade. Vagabond is now just ending her 4th season, the hull is Grey (RAL nn15 - where nn is a number currently missing from my memory) and she is now several shades lighter than newly applied gel coat to this specification. All is not lost, because you can buy small tubes of white pigment to add to the new Gelcoat and, by a process of trial and error, get a reasonable match. Like everything connected with boats, it take time and patience!

Happy matching!

[BobT]

Many thanks to you all for the info. Typically I have been unable to do much on "Escape" since putting up the post but will report back when I have experimented hopefully with some photos of after.
Very happy to hear other peoples experiences of gel coat repair/rubbing down.
Regards,
Bob

[BobT]

Spent an hour or two tackling the scratches on "Escape" and the attached photos show the results.  There is much improvement but by no means perfect. The pin pricks as I called them in the original post will need filling but most of the other scratches have either rubbed down or at least "cleaned out" so the black gelcoat shows rather than a white scratch.
The first photo is work in progress showing most of the scratches removed but more to be done to get the shine back.
Second shows the "pin pricks" still present but most of the other scratches faded as compared to the photo in the original post.
Photo 3 more of the same but showing more of the hull.
Lesson learnt is more fenders more often to stop getting the marks in the first place!!
Regards to all,
Bob