fairing fight

[dpollitt]

Wonder if anyone can confirm the order involved in fairing the inside of a head compartment....shower and vanity and head.

the guy who is doing it applied fairing all over, then sanded it down to a pretty rough finish, then applied 4 coats of primer.

when I saw this, I became a little agitated as it seemed that he had put the four coats on to cover up, not prime. it needed alot more fairing/sanding/fairing/sanding...then.....prime.

Can anyone confirm that I am right on this......not fairing once, priming and THEN doing some finishing sanding.

many thanks
david pollitt

[44'cruisingcat]

It might be a highbuild/primer he has sprayed. A normal primer won't hide much anyway, so if it's not fair it will show up when he sprays the gloss.

If I was good enough at it, that would be my sequence - fair with bog, sand, spray highbuild, sand, spray highbuild again, sand lightly, then paint.

[dpollitt]

Interesting
why would one not fair the original fairing compound to the finished surface one wants, then prime. Maybe, I am too house oriented.....compound until its near perfect then paint.

High build primer.....I wonder if thats what we are using...not sure.

many thanks for your reply
david

[Whimsical]

Originally Posted by dpollitt

Interesting
why would one not fair the original fairing compound to the finished surface one wants, then prime.

Try using a long board for half an hour on fairing compound then try it on high build and all will be revealed.
Oh my aching arms

Mike

[dpollitt]

Mike,
I sort of get your reply...but do tell me straight out....what is the difference b etweeen fairing compound and high build as it pertains to getting a smooth finish, ie in all the corners....you are a little over my head so ...be patient.

david

[Whimsical]

The highbuild is a lot easier to sand than the fairing compound.

Mike

[sobraon]

G,day Dave,

We have a lot of information and photos about painting and fairing on our website Refit pages that may be helpful.

April 2006 (Refit)

Whilst what you describe doesn't sound to bad it depends on how rough the fairing preparation is. Epoxy high build (primer) is designed to fill small scratches and imperfections and is not designed to fill large imperfections. If the initial prep work is rough it will still require further fairing before it will be ready for final polyurethane top coats. The smallest blemish will appear a lot worse under lighting inside your boat

I would recommend that the final topcoat have a small amount of flattening agent applied to it to give you a satin finish for interior work. It will give you a very professional look and help cover any small imperfections when viewed under bright lighting.



Above is the satin finish we achieved in our head and shower. Most of the sanding and fairing was done with power sanders for expediency. However, for a flawless finish it is imperative that the final fairing is done with a flat board ie. (Torture Board). The hull took us about 3 months of torture boarding to achieve this finish.




If you can post a photo and let us know what product your contractor is using we may be able to help you further. Let us know if you want any more information.

Fair Winds

Garry and Wendy

'SV' Spirit of Sobraon

Talkspot

[dpollitt]

Hello Garry and Wendy
what a great finish...you guys are pros.
the stuff we are using is Awlgrip kit....I t hink the number is 545...it is 1/1 ratio...I will get the actual numbers on the can today

Ok here is the question.....there are two head compartments. The first was treated to 4 coats of primer and now they are sanding .....but the really big imperfections....ie 5200 bulges etc remain. Now the second head has the fairing compound already sanded but very rough...ie same sort of things.....mostly at the corners etc. My contention is that we should not prime now but only after we have smoothed the edges, cut off bulges of 5200 etc. then faired again in those areas.....then prime.

How does that sound....or am I wrong.....prime now then perfect the edges then.....?

fair again or prime again?

Lovely job you guys do.....

I want to hire you!!!

david

[sobraon]

David,

Thanks for the complements.

It sounds like the contractor isn't doing the hard yards to give you the finish that you are expecting. By 5200 do you mean that there is still exposed sealant. If this is so, this definately shouldn't be primered over.

Whilst I am sure there are so reputable marine contractors out there it has been our experience that they are very few and far between.

Painting is the easy bit. Preparation is the real secret to the perfect finish.

[sobraon]

David,

Unfortunately I pressed the post before I had finished the reply.

The two most important things to consider when fairing and painting a head/shower is to ensure that it is waterproof and that it is fair so that cleaning is easy.

To achieve this I believe the correct procedure is as follows

1. fill all of the coves and imperfections with a bog mixture of polyester/microballoons/cabosil

2. fair the entire area with 120 grit. (all coves should be sanded by hand using your palm to achieve a smooth transition)

3. spray 2 coats of 2-pac epoxy high build followed by a disclosure coat of methylated spirit and food coloring

4. re-sand the entire area with 240 grit trying not to cut through the highbuild ( repeat 3 if necessary )

5. if there are no blemishes spray a thinned coat of epoxy high build (if your painter is good at his craft he should be able to achieve this without runs etc. so that the top coat can go on with out further sanding)

6. spray 2 coats of 2-pac polyurethane over the entire area. In my head/shower I rolled the floor after the rest was dry to minimise over spray.

The high build provides both the smooth surface for the top coat but also the waterproofing.

We have had a number of issues with marine contractors and it is one of my pet hates.

If you can send us some photos via email ( gary@prodigymotorsport.com ) or post them so that we may be able to help further.

Fair Winds

Garry and Wendy
SV Spirit of Sobraon

www.sobraon.talkspot.com