PPE for dry sanding antifouling

[Iain C]

I know that dry sanding antifouling is a Bad Thing. I am currently rebuilding my rudder (good job I checked...failed tang weld) and I need to sand all the a/f around the leading/trailing/top and bottom edges to glass it back together. I need to take all traces of a/f off and go into the laminate so the new glass is flush with the rest of the layup for a professional looking repair.

Question...is an organic vapours mask, paper hooded coveralls and gloves OK for this? If it makes any difference, it's International Micron Extra over about 6 coats of VC tar, and it will be done in my back garden away from anyone else.

 

[VicS]

I know that dry sanding antifouling is a Bad Thing. I am currently rebuilding my rudder (good job I checked...failed tang weld) and I need to sand all the a/f around the leading/trailing/top and bottom edges to glass it back together. I need to take all traces of a/f off and go into the laminate so the new glass is flush with the rest of the layup for a professional looking repair.

Question...is an organic vapours mask, paper hooded coveralls and gloves OK for this? If it makes any difference, it's International Micron Extra over about 6 coats of VC tar, and it will be done in my back garden away from anyone else.

Its a dust mask you require rather than an organic vapours mask although I think you will find that the latter is an effective dust mask.

Coverall with a draw string around the hood and elasticated cuffs and ankles sounds about right.
Good eye protection required as well.

Epoxy resin would be better than polyester resin as it will adhere to the existing laminate better. Appropriate glass cloth not the CSM that you would use with polyester

 

[misterg]

...about 6 coats of VC tar...

I think you'll find it nearly impossible to sand the VC tar - it clogs the paper. It can be quite easy to remove if you pick a cold day and go at it with a good scraper (it shatters & breaks off in flakes if you're lucky, taking the A/F with it).

Andy

 

[Simondjuk]

You must use an FFP3 mask. Many solvent masks are only rated FFP2 for particulate filtration. Check the FFP rating of your solvent mask before use.

 

[Elessar]

I know that dry sanding antifouling is a Bad Thing. I am currently rebuilding my rudder (good job I checked...failed tang weld) and I need to sand all the a/f around the leading/trailing/top and bottom edges to glass it back together. I need to take all traces of a/f off and go into the laminate so the new glass is flush with the rest of the layup for a professional looking repair.

Question...is an organic vapours mask, paper hooded coveralls and gloves OK for this? If it makes any difference, it's International Micron Extra over about 6 coats of VC tar, and it will be done in my back garden away from anyone else.

tip:

take the filters off the mask
place hands over filter holes
breath in

if you can't good

if you can the mask isn't fitting well enough.

Tighten it. Have a shave or Vaseline your beard.
If that doesn't work you need a different size mask, it isn't very clear they come in different sizes.

 

[VicS]

You must use an FFP3 mask. Many solvent masks are only rated FFP2 for particulate filtration. Check the FFP rating of your solvent mask before use.

Checked my 3M 4251 organic vapours mask .. only a P1 rating!

it isn't very clear they come in different sizes.

Ceratinly isn't. I did not know and I am sure I have never seen it mentioned before.

 

[prv]

A good vacuum attached to the sander (ideally a sander with extraction through the plate) will reduce the amount of dust your PPE needs to deal with.

Pete

 

[Simondjuk]

That's odd, Vic S, I was sure the 4251s I had were P2. Admittedly though, I only used them for solvent work so didn't really pay much attention to the P rating. Unless of coure they weren't 4251s. Anyway, that yours is a P1 just emphasises how what's good for one job may not be good for another.


I second prv's suggestion of the vacuum, only would warn that unless every single filter/piece of foam in it is removeable and washable, don't expect to use it in an enclosed space ever again as it will probably never stop spewing very fine dust. I find a wet vac, pre-filled with some water to 'catch' the dust is good when sanding paint.

 

[prv]

I second prv's suggestion of the vacuum, only would warn that unless every single filter/piece of foam in it is removeable and washable, don't expect to use it in an enclosed space ever again as it will probably never stop spewing very fine dust.

S'a fair point; my workshop vac is a Henry in which the only filter is the bag, so after carefully disposing of that there's not much else to hold dust.

Pete

 

[Csail]

Well a good clue is here, the establishment i worked for will deny this. Anyway my mum is the pharmacist in the chemist nearest to where i worked and most of the guys were dropping dead before 50.I and them were all issued with good kit but the older boys didn't bother. I wouldn't go in certain areas without it on, our kit was Sabre. Thought it was in here ....must be on boat. Not cheap but nor is life. dust masks....better than nothing but would you put a home made air filter in your Ferrari or bite the bullet and get a real one for 100 quid. Choice is yours.Back soon off for a fag!

 

[ghostlymoron]

it will be done in my back garden away from anyone else.

I removed the anti-foul in my garden on the lawn. The patch remained devoid of grass for 6 years!

 

[aquaplane]

You haven't said why you are dry sanding?
I wouldn't dry sand it at all.
I would strip it with Nitromors or a Sandvic scraper and then sand it with wet and dry. Tyvec suit and Marigolds for that.

 

[pappaecho]

Sanding down the antifoul makes no sense as the particles are easily breathable.

I would use either an electric hot air blowers or SWMBO's hairdrier ( when she is out shopping) to soften the antifoul and then strip it with a Scarsten scraper or similar.

Failing that good old paint stripper should be ok because the base coat is epoxy tar which is not affected by methylene chloride, and again use a scraper. Relatively large pieces of scraped antifoul are not breathable

 

[Hadenough]

Get one of these

http://www.oldewindowrestorer.com/proscraper.html

 

[Hadenough]

Or even one of these

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=150647045136

 

[Boathook]

Or even one of these

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=150647045136

I've got something like that. Works well, though on mine the blade corners are square and it is very easy to gouge the hull. PBO did an article about removing antifoul quite a few years ago and the scraper with vaccum cleaner came out as an reasonable option.
I have also dry sanded many years ago with a vac type cleaner with a cartridge filter. The cleaner also could take a bag at the same time for small quanties of dust. The antifoul dust went through both.

 

[nigelmercier]

Question...is an organic vapours mask, paper hooded coveralls and gloves OK for this?

Just do it outside on a windy day, and stand to windward.

 

[vyv_cox]

Or even one of these

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=150647045136

We stripped the whole hull with one. As said above, the blade corners gouge easily, so grind them off to a chamfer. The vacuum cleaner attachment on ours is not too secure so I added a short length of hose and a clip. Made a good job with minimal dust.

Previous to that I have stripped hulls with Dilunett, a rather tedious job but worked fine. On a rudder it would be a good choice, especially if you can work inside where it is a little warmer.

 

[VicS]

Previous to that I have stripped hulls with Dilunett,

Now marketed by Owatrol under the name "Marine Strip"

.

 

[Iain C]

Thanks for the tips all. I will give it a go with a scraper first, and then see if I need to sand.

What I don't get is FFP3 v organic vapours. I bought an organic vapours mask to do some headlining gluing with some pretty evil contact adhesive. It's a big blue rubber thing, with two headstraps, and sealed all the way around my face perfectly. After 15 minutes, with all the hatches open, I removed the mask and nearly went off with the fairies...the stink was unbelievable, and there had been no hint of it whatsoever with the OV mask.

Yet the FFP3 mask, presumably designed to keep out nasty bits of dust, looks no more secure than some poxy B&Q type carpenter's dust mask!