Hull prep revelation for all

[JimC]

Yes, they are for use with an electric orbital sander, but I used them with my electric palm sander and they worked fine, so much quicker than using sandpaper

When I've tried to use my 5" random orbital sander on the boat I've not found it much good on the convex curved surfaces as it's too rigid to conform to them. Is a palm sander better in this regard?

 

[Mavis]

When I've tried to use my 5" random orbital sander on the boat I've not found it much good on the convex curved surfaces as it's too rigid to conform to them. Is a palm sander better in this regard?

All I can say is that on my little 100mm square Makita palm sander it was a doddle. Also very light on the arms!

 

[capetown]

When I've tried to use my 5" random orbital sander on the boat I've not found it much good on the convex curved surfaces as it's too rigid to conform to them. Is a palm sander better in this regard?

Sometimes a softer backing pad cures this.
Or a sponge interface, this fits between the backing pad & and disc

 

[JimC]

Thanks, I'll try one.

 

[sarabande]

has anyone any knowledge of a (hose) water powered sander ? There might be sufficient energy in tap pressure to turn a scrubbing pad, and also prevent air-borne dust.


Of course, you would need to watersand with a recovery tank system nearby - just as some hull pressure washer units have.

RETHINK

What about an air-powered sander with a hose feeding into the abrasive pad ? No danger of electric shock !

 

[capetown]

I did try a pump up type garden spray, this was tapped to the airline.
Works okay up to approx 45degrees but then the mess just runs down your arms.

Can we see a YAPPING coming?

 

[biscuit]

+1 for Silverline/ Stanley -type palm and pole-sander plus a roll of mesh abrasive, with lots of water and disposable overalls and mask.

https://www.machinemart.co.uk/shop/product/details/040715928?da=1&TC=GS-040715928

 

[Plevier]

These products seem very similar to what I use, links below from eBay

Very cheap, the rolls lasts many years and can be WET sanded, it normally takes me 2 hrs to do my hull, 33'

http://www.ebay.co.uk/itm/Sanding-Mesh-Roll-5m-60-Grit-ts-634001-/191380929810?

http://www.ebay.co.uk/itm/Silverlin...525?pt=LH_DefaultDomain_3&hash=item2a3cc8848d

I think this product is used in the building trade for sanding dry lining filler.

B & Q used to sell single sheets, but expensive

You can buy rolls of that in Toolstation too
http://www.toolstation.com/shop/p41259

Not sure it's the same quality as Abranet though.

I notice the Silverline (Toolstation) one is silicon carbide, Abranet is aluminium oxide. Don't know which is better.

 

[cliff]

RETHINK

What about an air-powered sander with a hose feeding into the abrasive pad ? No danger of electric shock !

Works for me though the bearings are not sealed so they need dried and oiled after use or changed when they seize - simple job though on the DA and jitterbug sanders.

 

[Marine Reflections]

Today I have been sanding down my hull, removing the old antifoul ready for the new. As every boat owner knows it’s an awful but necessary job. I usually kit myself in overalls, goggles mask and gloves and use a small 100mm palm sander but it is a laborious and slow.

While I was working away a mate came over for a chat and told me to try these instead of the sandpaper I was using. They where circular sanding sheets that looked like a piece of gauze and meant to fit onto an orbital sander, but I do not own one. However by putting a small fold on two opposite edges the sheet fitted into the jaws of my palm sander.

The result was a total revelation to me and made the task almost enjoyable. I did the whole hull in a couple of hours and took last season’s entire antifoul coat off to a really smooth finish, a job that usually takes two of us all day. The sheets are called ABRANET and the ones he gave me where 150mm diam. P80 grit. No doubt other companies make them, and no I do not have an interest in the company. They also work equally well on my varnish work. Do yourselves a favour and try these out.

Hi Mavis,

Thank you for the heads up on Abranet discs, despite them being around for quite a while, it is really those in the know or professionals from various trades that have tried them.

We have discussed them on here before a few times, but that does not mean that everyone knows about them or the benefits.

The majority of boaters would not have heard of them, so no-one is saying the advice is not welcome.
It is just that all too often, advice is up for cross examination on here by other professionals or boaters with many years of experience.

As a professional yourself, you see fit to pass on information that would benefit others, Pete is doing nothing different and is actually doing you a favour, not being anti-social. Bare in mind that the advice Pete is offering is more general, it might not seem relevant if you are isolated on a large hard standing, some distance from other boats and people.

The thread gets read by many others on here and the internet, those readers are more often than not, surrounded by other boats with lots of people walking about or working.

Practices change and the methods improve, you yourself have only just discovered these discs and you are a professional, so it would be safe to assume others are equally unaware of the correct practice.
Certain practices (such as anti-foul removal) are up for debate quite often and what was once acceptable is now gradually being frowned on.

It is slow progress on here and together we only represent a small percentage of the boating community as a whole, but the more we brainstorm and look into the safety and the impact certain practices have on those around us, the more friendly and safer marine environment we will all enjoy.

If I was grinding steel next to your boat with the particles landing on your surfaces, you would hardly be interested in what disc I was using.

The Abranet discs are so effective due to them being designed for extraction. In short, they allow discarded particles to pass through the membrane of the disc much easier than the previous holed discs.
Without extraction, the considered safer method is to use them wet.

Without going to the expense of correct extraction equipment I guess reluctantly I would suggest sanding wet. The problem I personally have with this, is that I believe once the water used as a carrier dries up, you are left with the Total Dissolved Solids left on the floor underneath the boat. This is only waiting for a windy day to be released into the marina.

With extraction you can sand wet or dry, a stepped down 18v dual action sander (like a Mirca) that allows fitment to a hoover is one option, this hoover could also be a wet extraction hoover if you wanted to sand wet.
You would then simply have to dispose of the toxic particles, in the hoover bag or the slurry from the wet vac. Ask your marina if they have a closed loop system this could be added to, or have a specific hazardous waste container.

Tony

 

[Clive]

Firstly, dry sanding a bad idea, whilst you may have a mask etc, those down wid will not. One should only wet sand.
Having said that the silverline sanding mesh is brilliant (available from Amazon and other places). Comes in 5m length, lasts for years.

Cut off a length and wrap it around a sanding block and with a running hose just a few hours sanding and the boat is completed. rinse off the residue down the soak away so wind does not stir up the dust to impact others.

ps on the joint between the keel and the hull I wrap the mesh around a tube to get a good smooth joint.

 

[Chi34]

The Mirka hand kit connected to a good hoover is very effective.
Very useful around the house too.
http://www.axminster.co.uk/mirka-handy-sanding-block-80-x-230mm
Worth pointing out that it's not necessary to remove all the antifouling. Less damage.

 

[ronsurf]

14 posts before the abuse started, not bad!

Single sheets can be obtained from a surfboard shaping supplier, there are a few around. They're used for shaping the rails.

Never thought to use them for this though, thanks for the tip!

 

[Spirit of Glenans]

Why bother? A rub all over with w+d to key the surface and remove any loose bits has always worked for me. When there is considerable build-up I'll consider scraping it all off, using an oscillating multitool or similar.

 

[bigwow]

Why bother? A rub all over with w+d to key the surface and remove any loose bits has always worked for me. When there is considerable build-up I'll consider scraping it all off, using an oscillating multitool or similar.

+1 What doesn't come off with the pressure washer stays on, for me, unless it flicks off with the scraper.

 

[PabloPicasso]

+1 for ABRANET I use 40 grade for antifoul and 240 to prepare a surface for gloss paint.

They are used in the car body repair business.

Although they are expensive at circa 50p each they last longer than 10 paper discs.

Good luck

Can you tell me where you bought 40 grit abranet please? We're they disks or sheets?

Thanks

 

[KREW2]

The best 9 quid I have ever spent.

I bought a pole sander from toolstation.
Fitted cut down sheets of 350 wet and dry, used hosepipe a bucket of water, and did half of my hull in 40 minutes
Great not to have blue water running down my sleeves up to my armpits.
I had 3 people asking me where I bought it from, so I will be buying shares in pole sander ltd

 

[Hadenough]

The best 9 quid I have ever spent.

I bought a pole sander from toolstation.
Fitted cut down sheets of 350 wet and dry, used hosepipe a bucket of water, and did half of my hull in 40 minutes
Great not to have blue water running down my sleeves up to my armpits.
I had 3 people asking me where I bought it from, so I will be buying shares in pole sander ltd

350! May as well use a chamois leather!

 

[Dipper]

+1 What doesn't come off with the pressure washer stays on, for me, unless it flicks off with the scraper.

+2 I've never sanded mine. When my boat was in a boat yard for damage repairs, the boat yard didn't sand eroding antifouling before repainting either. It doesn't even tell you to sand down in the preparation instructions on my tin. All it says is to rinse with fresh water and allow to dry. I don't know why people bother.

 

[KREW2]

350! May as well use a chamois leather!

No, I don't want to remove all the old antifouling. I just want smooth off the hull to fair in where old has flaked off. I don't like the under water bit looking like a moonscape.
What I have used has done the job lovely.