Cleaning laminate with gelcoat removed

[dweeze]

Hi - can anyone tell me their best way to remove the fine dust thats created when you sand the gelcoat layer off a deck. Have already got acetone waiting but was wondering whether there was an easier method (washing with H2O or the like)

Thanks - Tim

 

[oldsaltoz]

G’day Dweeze,

Just plain old water, two reasons, One, less damage to our environment: I would just hose the deck fist, no detergents needed, you know the areas water will lay so work toward them and leave them till last.

And Two: water and most contaminants don’t mix, so keep a sharp eye open for any signs of water forming beads, a sign of contamination that will have to be removed.

You may need to wash a second time if you have been walking in the dust, a broom or brush will do, again looking for beading of water.

Only apply Acetone just before you start other lay-up be it glass, paint or gel, just let it dry for a couple of minutes first, I use only white cotton rags with Acetone and lots of them.

Needless to say you will to protect yourself when using Acetone, it will go through your skin and has been listed as a carcinogenic, and to think up to a few years ago that’s all the girls had to clean the nail polish off.

Avagoodweekend……

 

[BrendanS]

not sure if anyone has told you this, but you are a gem on these forumns. You keep posting advice on anything related to grp/gelcoat and don't seem to want anything in exchange.

To my simple mind, that makes you a star

 

[oldsaltoz]

G’day Brendan,

Thank you for your kind words, but the facts are that I have been in, under, over, alongside, in front and behind boats, in and out, of the water most of my life.

I think in the last 40 + years I have made about every mistake you can at some time, armed with this knowledge I’m in a good position to save others making some the same errors, so why not.

I tried to retire when I was 55 and did for almost 3 years, having finished a refit of the boat, the house and both vehicles as well a few jobs on other boats, I ran out of regular work and couldn’t sit down, so back into it.

Now I’m a licensed weterproofer and needless to say the whole system is based on fibreglass, this keeps me out of trouble between boat repairs, refits, rewires, modifications, renovations, cold box building, and the still a have time for my first love, sailing. Some of us never learn.

I plan to give up working about 3 minutes after I stop breathing. I’m not as fast as I was, but I do a better job; with more know how and less errors and a much better tool kit.

Keep in mind that I am no expert, but I do take the time to keep up with the latest innovations in the industry and have a habit of testing things to destruction if in any doubt about their suitability for a particular application, like snapping a section of laminated keel and a carbon fibre mast, both test pieces not the finished product I’m happy to say.

Avagoodweekend……

 

[Ships_Cat]

I second that.

I too find Oldsaltoz's posts very informative.

John

 

[dweeze]

oldsalt - Ta for this. I had it in the back of my head that it was fine to wash with water but wanted to be sure. Was a bit concerned that washing with water would just lead to the fibreglass taking it in - not good seeing as its taken me the last month to get moisture back out of the core where it had leaked in.

A further question from your answer. If its ok to wash the exposed deck down how permeable is fibreglass when it doesnt have any form of barrier or gelcoat over it? Does it need a complete soaking before it starts to take in water ?

I like your Aerogard signature. Been a while since I last heard it.

Tim.

 

[Evadne]

Not wanting to contradict Oz's advice, from which I too have learned a lot over the past few years of reading these fora: if you are near to electricity then a small domestic vacuum cleaner will remove an awful lot of the dust.

 

[dweeze]

Yea ta - have been vaccuuming. What I am finding is that even after vaccuuming there is a small residue of the dust left, even with a good vaccuum cleaner - even after letting the dust settle overnight. I guess because its so fine. My main concern was whether the residue may cause bonding problems when I re-coat the deck.

 

[oldsaltoz]

G'day again Dweeze,

Now that the gelcoat or other protection has been ground off, you have thousands of tiny hollow straws of raw fibreglass exposed to the elements and in particular moisture, scary ay.

well not really, provided you let it dry and it will not take long, it's not like you are launching her till you can get back some in 2006. It takes a long long time; some pressure and some variation in temperature to even start doing any damage, as I said, just ensure it's dry when ready to coat.

Then you need the mask and white cotton rags for the Acetone wash down, the Acetone will suck the very last of the moisture, it's like thirsty Metho when it comes to attracting water, so don't let it sit in a puddle to evaporate, it may leave some of the moisture behind.

Have you checked the core to ensure you have no rot, sealing it in will only make the next fix even bigger, if moisture is trapped it will continue to rot the balsa core.

You can save some time and weight if you fair the deck first using 'Q' cells, they are good enough to use below the water line as they are 'closed cell' and cost less than Micro-shears.

You can even duplicate the moulded non slip areas, just find a friendly old salt with a nice clean non slip are the shape and size you would like, give a good clean, at least 2 to 3 coats of wax release agent, slosh on some resin and lay a single layer of 250 gram glass on top; add a little more resin just to wet it out, then lay a big sheet of clear plastic over top, tape the edges and suck all the air out so the plastic pulls down onto what will be your mould.

Return next day and pull her off, clean his deck just to show your a nice bloke and, when you have your deck ready to gelcoat or pint, apply the release agent to your new mould and spread some resin and 'Q' cells over the underside of you new mould, taking great care not to trap any air, drop on the deck by putting one short side down first, then bend it a little so that no air it trapped under it as you lower it onto the deck; tape it and suck the air out to pull it down to the hull and you have a perfect non slip area ready to paint. Use gelcoat rather than resin if you plan to gelcoat you deck. Have a practice run with Mums old bath mat if you like.

I would as always, advise you use only epoxy resins for this project, less weight and more strength is an advantage, plus it has much much better water resistants.

Andavagooweekend......

 

[oldsaltoz]

G'day Dave,

You are correct Dave, and I agree a vacuum cleaner will remove a lot of dust.
However, As this project has been going for a month I would imagine the weather gods have removed any loose material.

Wetting the deck with plain clean water will show any areas that are contaminated, the water will form beads. providing some good time saving information before coating.

As the deck is going to get wet using this technique, it will save time and power if hosed off, a small bit of masking tape on the hull under the normal overflow points will cause the dirty water to drop clear of the hull into a bucket if required.

Avagoodweekend.

 

[dweeze]

I had a good chuckle at the advice on how to re-new the moulding. Very smart.

Ta for the help. T