3M Compound/Polishing

R

RobBadgie

Active Member
Joined
4 Mar 2013
Messages
43
Visit site
I'm planning to use 3M Marine Imperial Compound and Finesse It II with an orbital power tool. But I cannot find any advice about how much I actually need, for the hull of a 10m boat. Anyone out there have experience of this? Also, can I get away without the Imperial Compound? The gel coat is dull white but not discoloured.

Thanks vm in advance!
 
I have been using Finesse It in different grades for a few years with good results. I haven't got the bottles here to check the grades, but I believe it is II and III.
I get mine from a car repair supplier, and the man behind the counter tells me he is certain that the stuff is no different from that in the bottles marked 'Marine'
 
RobBadgie said:
I'm planning to use 3M Marine Imperial Compound and Finesse It II with an orbital power tool. But I cannot find any advice about how much I actually need, for the hull of a 10m boat. Anyone out there have experience of this? Also, can I get away without the Imperial Compound? The gel coat is dull white but not discoloured.

Thanks vm in advance!
Click to expand...
You need a proper polisher- Silverline is the usual base model at about £50. Anything less simply will not get the paste cutting. And a decent 3M wool bonnet.
Assuming the boat isnt a real mess, 500ml of both should be enough, but I thought the compound was in 4kg tubs ?
 
Hi Rob, I'm in the car body repair industry and you can use a good half bottle on a flat and polish on one car, I would think 2 bottles to start and keep a water spray bottle handy and lightly dust area to stop it going gloopy. I'm going to flat and polish my small 7m boat in the spring top to bottom and going to try 2000 and 3000 grade foam orbital discs to polish off dullness before a polish with finesse then a sealer to help the weathering. might give it a good wash with a oxalic acid first although I have not had stunning results with this so far and find nothing beats elbow grease versus all the magic bottle cures.
 
A little goes a long way. If the gel coat's just a little tarnished, as the OP describes, a long, long way. I'd have thought a litre ought to do it, or even half that.
Keep the working area wet: frequent spraying with an old squeegy bottle of water, perhaps with a dash of washing-up liquid, helps a lot.

P.S....beaten to it...
 
Hi, the Imperial is roughly 1 litre and the Finesse 0.5 litre. I will get a litre of each as I'm sure it will get used....
 
Last winter I compounded my Fulmar, which is of similar size. I followed the instructions in this web page. http://www.cfsnet.co.uk/acatalog/Gelcoat_Polishing.html

In total I used just under 500ml of G3 and G10 plus a couple of medium and fine foam pads. The Silverline polisher works well and worth getting. For small areas around fittings or the deck edge/waterline you will need I multitool, I use a Fein but there are cheaper ones available. You also need a plant spray to keep the foam and surface damp during compounding. I would also suggest getting a platform to work on. The one I used was this one from Machine Mart. https://www.machinemart.co.uk/shop/product/details/4-in-1-scaffold-ladder

If you want to see some before and after photos look at http://s1294.photobucket.com/user/ConcertoFulmar32/library/?sort=3&page=4 and http://s1294.photobucket.com/user/ConcertoFulmar32/library/?sort=3&page=2.

Once finished I would recommend sealing the compounded surface with Crystal Glo Acrylic Marine Treatment. http://www.cfsnet.co.uk/acatalog/Crystal_Glo_Acrylic_Yacht_Polish.html

The compounding and polishing will take you about 3 to 4 days to complete on your own. Wearing eye protection and boiler suit is highly recommended.
 
This is a question I had been planning to ask here, because my dinghy's hull is yellowed and scuffed, with numerous shallow scratches and immovable tyre-marks, as well as the contrasting bright white patches where enormous name-decals must have been in place for thirty years, while the rest of the hull is variously creamy grey or a bilious yellow...

...just how cheap can I go, in terms of a rotary polisher? Is there a Li-ion battery option? Not that that will be cheaper, but I keep the boat very far from any power points.

For the fairly neglected condition my hull is in, is there an obvious choice for which grade of rubbing compound I need?

And...given that a certain thickness of the gelcoat will be removed by rubbing, is there any greater consequent water-ingress/moisture in the glass, afterwards? Not much of a problem in a dry-sailed dinghy I can see, but I'd gladly paint her with epoxy if it was recommended.
 
I went and washed it down today, here is a photo of the hull after the wash down. It looked less shiny before the wash down. Still not sure whether I need the Imperial or if I can go straight to Finesse.....

Hull.jpg
 
I did this on my Westerly Ocean 33, which has a dark blue hull, a few years ago and was very pleased with the result. I cannot recall the quantities I used but, as has already been said, get a decent polisher, (I used a Rupes which is very light but equally expensive), and the proper 3M lambswool bonnets, you'll need white for the compounding and yellow for the polish. If you're in any doubt, I would try a small area first with the Finesse-it and see if this does the trick, but it is a lot less aggressive than the compound. I did not find I needed a water spray using these products. Finish with your wax of choice, I used 3M at the time but then found Megguirs Premium Marine Wax to give better results.

I have since switched to G-Tech products which you might like to investigate, it's a different technology.
 
I refrained from posting so far in this thread, as so many people seem to believe in compounding using electric machines. I don't. Gelcoat is a scarce resource on most boats, and it's very easy to remove it through amateur compounding. My last boat was 24 years old when I sold her, and I'd owned her for 19 years. I only ever hand-polished the topsides - 2 coats of Meguiars polish followed by 2 coats of Meguiars wax. All very easy by hand, both applying and polishing off. If I were you, I'd miss out the compounding and go straight to the Finesse-it. But I would suggest you apply wax afterwards to protect the shine. Here's a pic of my 24 year old boat earlier this year...

sc21_zps6f9b6665.jpg
 
RobBadgie said:
I went and washed it down today, here is a photo of the hull after the wash down. It looked less shiny before the wash down. Still not sure whether I need the Imperial or if I can go straight to Finesse.....

View attachment 48099
Click to expand...

Going by the pic,I would also skip the compounding stage on this, just the later (finer) stages inc protection.
 
pvb said:
I refrained from posting so far in this thread, as so many people seem to believe in compounding using electric machines. I don't. Gelcoat is a scarce resource on most boats, and it's very easy to remove it through amateur compounding. My last boat was 24 years old when I sold her, and I'd owned her for 19 years. I only ever hand-polished the topsides - 2 coats of Meguiars polish followed by 2 coats of Meguiars wax. All very easy by hand, both applying and polishing off. If I were you, I'd miss out the compounding and go straight to the Finesse-it. But I would suggest you apply wax afterwards to protect the shine. Here's a pic of my 24 year old boat earlier this year...

sc21_zps6f9b6665.jpg
Click to expand...


Great condition pvb.
Yes, there's a lot of truth in that statement.
Many believe that using a polisher with some heavy compound forms the basis of regular maintenance, it doesn't.
Compounding is a form of correction, only to be performed after neglect.
Once you have the condition 'performing' there is no reason why the later finer stages of polishing and adding protection couldn't be done by hand.

Personally I find it easier to fine polish via a machine, but always wax by hand.
 
djrussell0 said:
Hi Rob, I'm in the car body repair industry and you can use a good half bottle on a flat and polish on one car, I would think 2 bottles to start and keep a water spray bottle handy and lightly dust area to stop it going gloopy. I'm going to flat and polish my small 7m boat in the spring top to bottom and going to try 2000 and 3000 grade foam orbital discs to polish off dullness before a polish with finesse then a sealer to help the weathering. might give it a good wash with a oxalic acid first although I have not had stunning results with this so far and find nothing beats elbow grease versus all the magic bottle cures.
Click to expand...

That's a good process, starting with an oxalic wash to brighten the gel, this will also remove the tiny layer of water scale (so you aren't working on TDS) rather than the gel coat.
As you know it won't give the results, but will help you prep for being in a marine environment.

Yes, you will have good results with foam discs, Trizact 1500 - 3000 seem to work well but as you know they are all fairly similar, just the Trizact seem to bite better on gel than others.

Can of course completely skip the compounding stage due to using the discs to flat as you know and move straight on to Finesse it, but do get the marine version of Finesse it (09048) it is different both in chemical make up, clean up is easier, also less working oils so won't give you a false finish.
 
Marine Reflections said:
That's a good process, starting with an oxalic wash to brighten the gel, this will also remove the tiny layer of water scale (so you aren't working on TDS) rather than the gel coat.
As you know it won't give the results, but will help you prep for being in a marine environment.

Yes, you will have good results with foam discs, Trizact 1500

thanks for the tip about marine finesse it

you know your onions, a lot of people including experienced painters don't seem to accept or acknowledge that a lot of compounds out there are full of bullshit fillers to make the product look good and to speed the job up.

I find 3m products have less fillers and you actually get more or less what you see.

Dave
Click to expand...
 
djrussell0 said:
Marine Reflections said:
That's a good process, starting with an oxalic wash to brighten the gel, this will also remove the tiny layer of water scale (so you aren't working on TDS) rather than the gel coat.
As you know it won't give the results, but will help you prep for being in a marine environment.

Yes, you will have good results with foam discs, Trizact 1500

thanks for the tip about marine finesse it

you know your onions, a lot of people including experienced painters don't seem to accept or acknowledge that a lot of compounds out there are full of bullshit fillers to make the product look good and to speed the job up.

I find 3m products have less fillers and you actually get more or less what you see.

Dave
Click to expand...

Thanks for the compliment Dave

Yes, I was kind of dancing round the filler subject, albeit in a different thread, you seem to have cut to the chase. :D
Click to expand...
 
Last edited:
djrussell0 said:
Marine Reflections said:
I find 3m products have less fillers and you actually get more or less what you see.
Click to expand...
I gave the boat a once over before winter and , for a change, tried some Autoglym Resin on a small area as an experiment . ARGG.. it was like glue on the wool bonnet and almost impossible to wash out. What the hell is in that stuff !!
Back to the 3M for me !!
Click to expand...
 
gjgm said:
I gave the boat a once over before winter and , for a change, tried some Autoglym Resin on a small area as an experiment . ARGG.. it was like glue on the wool bonnet and almost impossible to wash out. What the hell is in that stuff !!
Back to the 3M for me !!
Click to expand...

Gavin, tell me you didn't use those new wool pads with car products..
 
You must log in or register to reply here.

Share this page

Top