Polishing Gelcoat or Not ???

[Sheppy]

One of the jobs I'd like to get around to is giving my boat a good polish to get her looking like she did when she rolled out the yard all those years ago.

On here, in magazines, or by word of mouth, I hear about people taking powerful electric sanders to boats and doing a 't-cut' style cut and polish.
Is this really a good idea? After all, gelcoat isn't very thick. And how do you know previous owners haven't 't-cut' the gelcoat to hell prior to selling? What should one really do to bring a boat back to a good shine and colour?
There must be safer methods out there that aren't quite so abrasive?

 

[gjgm]

One of the jobs I'd like to get around to is giving my boat a good polish to get her looking like she did when she rolled out the yard all those years ago.

On here, in magazines, or by word of mouth, I hear about people taking powerful electric sanders to boats and doing a 't-cut' style cut and polish.
Is this really a good idea? After all, gelcoat isn't very thick. And how do you know previous owners haven't 't-cut' the gelcoat to hell prior to selling? What should one really do to bring a boat back to a good shine and colour?
There must be safer methods out there that aren't quite so abrasive?

Rotary polishers dont turn that fast, say 800-2000 revs.
If the boat is really bad, then of course you will need something aggressive, but otherwise you use the right foam/wool head -they also vary in their "cut" with the right compound and polish.
Obviously it isnt smart to be whistling away while cutting right through your gel, so start with something mild and see if that was enough.
Somewhere on the web sailing.net or something there is a good explanation, but otherwise try youtube.
M.Reflections is the man in the know if he pops along, but meantime there are some threads on this on pbo forum over the last week.
Realistically, you need to invest 100 notes for a Silverline and some gear, or 200-300 if you want a more pro polisher. If you are worried cleanyourcar do a DA polisher for about 120 that is safer, but perhaps doesnt have the grunt for a badly faded boat, but will be fine for most uses.
Also look up sailingtoday.something for polisher reviews.. they also reviewed polishes etc

 

[Sheppy]

Thanks for that, some useful info. I have a small polisher that I bought from boatsheen.com and that kind of worked on a previous boat but the shine never seemed to stay very long, even after lots of wax.
Ironically, I found a better finish when doing it all by hand but it's just such hard work!!!

 

[Piers]

One of the jobs I'd like to get around to is giving my boat a good polish to get her looking like she did when she rolled out the yard all those years ago.

On here, in magazines, or by word of mouth, I hear about people taking powerful electric sanders to boats and doing a 't-cut' style cut and polish.
Is this really a good idea? After all, gelcoat isn't very thick. And how do you know previous owners haven't 't-cut' the gelcoat to hell prior to selling? What should one really do to bring a boat back to a good shine and colour?
There must be safer methods out there that aren't quite so abrasive?

The important thing to consider is the abrasivness of the compound you use. T-cut, for example, is far too abrasive for gel coat. A favoured product is 3M Perfect-it™ lll Fast Cut Compound, used with a slow turning rotary polisher (http://solutions.3m.co.uk/wps/porta...pplies/ApplicationProcesses/GelCoatFinishing/).

This asumes, of course, that the gel coat in question has become faded and non-glossy. Using this product will bring back the shine, after which you should use a good polish (such as the 3M hard wax which is based on Carnuba) monthly.

(Not connected in any way to 3M or their products other than being a very happy user!)

 

[Sheppy]

Just to be clear, I wasn't suggesting using anything from the car market, t-cut was just a term of example.
I bought some cutting and polishing compound from BoatSheen when I bought the electric polisher but I didn't have a huge success. She looked great for a short while but then started to fade fairly quickly. I just don't like the idea of cutting into very thin layers of gelcoat. Other people talk about wet sanding, but that must take off layers?
Thanks for the recommendations on products, I'll certainly look into those. Only I'm still a little worried about how thick the gelcoat is, but perhaps it's not that much of an issue.

 

[longjohnsilver]

I've always started with Farecla G10, most others recommend G3 but imho that's too harsh, G10 is more a liquid than a paste. Have used it for about 15 years with good results. 3M polish seems good but a huge range to choose from.

 

[Greg2]

How much you want to cut back on the gel will depend upon its condition. The 3M product is very good where you don't need to take much back and there are graded compounds that will take more away if necessary. Obviously the less abrasive you can get away with the better.

I have used Meguiars products for several years and found them to be excellent. I start with the de-oxidiser to get the ingrained dirt off, then a couple if coats of polish to seal the gel followed by a minimum of two coats of wax. Once a year is all it needs and it still looks good when it comes time to do u again.

 

[Sheppy]

Thanks again.
Just off now for a run up the river as my Bro is visiting.
If you're about John I'll wave as we go past.

 

[Nick_H]

The important thing to consider is the abrasivness of the compound you use. T-cut, for example, is far too abrasive for gel coat. A favoured product is 3M Perfect-it™ lll Fast Cut Compound, used with a slow turning rotary polisher (http://solutions.3m.co.uk/wps/porta...pplies/ApplicationProcesses/GelCoatFinishing/).

This asumes, of course, that the gel coat in question has become faded and non-glossy. Using this product will bring back the shine, after which you should use a good polish (such as the 3M hard wax which is based on Carnuba) monthly.

(Not connected in any way to 3M or their products other than being a very happy user!)

Yep, my polisher used 3M fast cut this year, and I was impressed at how easy it was to get a good shine even on the heavily oxidised bits that face the sun. It's fairly aggressive, so you have to go easy, but it does mean less elbow grease on a faded boat.

 

[BartW]

there is a article in MBM in the last issue about the subject,
I didn't read it, so don't know if usefull,
but maybe worth having a look.

 

[rafiki_]

I use the Silverline polisher from Boatsheen once a year, and polish by hand 2 or 3 times. Initially I used the Boatsheen products, but use whatever I have to hand now. All work well on rafiki.

 

[Marine Reflections]

One of the jobs I'd like to get around to is giving my boat a good polish to get her looking like she did when she rolled out the yard all those years ago.

On here, in magazines, or by word of mouth, I hear about people taking powerful electric sanders to boats and doing a 't-cut' style cut and polish.
Is this really a good idea? After all, gelcoat isn't very thick. And how do you know previous owners haven't 't-cut' the gelcoat to hell prior to selling? What should one really do to bring a boat back to a good shine and colour?
There must be safer methods out there that aren't quite so abrasive?

Some great advice offered already, just to add:

3M Gel coat finishing system

The safest method would have been attention prior to this happening.
Gel coat with oxidation has already gone past the preventative maintenance stage and correction is called for.

The least aggressive - most efficient stance is the safest you can hope for when correcting, you do not know the true depth of gel coat until it is too late, so you are correct to give it caution.
How do you know previous owners have not compounded it to death? you don't! The high points are most at risk, you would start to see speckling of a second colour coming through.
That said it would be my guess that the average gel coat could withstand at least 25 full compound and polishes within its life, as even with full corrections you are only working with 2-3% of the gel coat.
How many should you give it from new? ....none!
One method I see only too often is people adding polish/sealant or wax to an oxidised gel coat in the attempt to build up the lows to a reflection rather than polish enough down to form the same.

The problem with this 'safe' method is that air gets trapped in the highs and lows or small fissures in the gel and the trapped air continues to oxidise the surface behind the scenes.
When the product fails and erodes away not only is the oxidation still there, but it has got worse!

The safest method, is to follow the advice in the above video, get the surface to a performing, highly reflective finish and maintain that finish as best you can with ample protection when needed.

Don't spend hours deciding over this product or that, that is for the pro's, if it is compound then this will work, if it is polish this will polish, wax will wax and so on. Use what you have in the toolbox.

 

[Sheppy]

Thank you all once again, very useful advice indeed.

It seems then that my concerns are quite justified but alas I guess I'll just have to get on with it now I have all the ammunition I need.