Advice Sought - Removing / Grinding Horiztontal Deck Welds

[MisterBaxter]

Hi MrBaxter.. thanks for this advice. Much appreciated. I have seen people reccomend a full face plastic shield AND wear goggles underneath. If a shield comes with a "hat" even better..

That sounds good. I used to have a chainsaw helmet with a fine mesh visor and built in ear defenders. One of them over goggles and a mask would give you really good face and hair protection. It wasn't expensive from Screwfix as I recall.

 

[Bouba]

Do want to cut at the bottom then lift the wheelhouse off with a crane, or are you cutting in sections. Is the boat on the water. With you being so close to other boats you need to inform the owners of your intentions as one spark off grinding on fibreglass will mark it .

This is very important......one of our forumites had his big, very expensive, boat peppered with metal filings from angle grinding on a nearby boat or dock....it was a major insurance claim and a massive task to remove each of the millions of imbedded shards. So check which way the wind is blowing and build barriers out of cheap materials like wood, hardboard etc

 

[PaulRainbow]

We had a big steel boat visit our marina, which was put on the berth beside us. One of the crew thought it would be an ideal opportunity to clean the rust from the many, very large, external mild steel chain plates using a big grinder with a wire brush on it. I spotted her before she did the whole side of the 80+ foot boat, but not before we had wire brush bristles here, there and everywhere. Not to mention the rust, old paint and crap. She was quite indignant that i asked her to stop and couldn't see a problem. Luckily this wasn't anywhere near as bad as red hot grinder sparks, but still took a good while to remove the bristles the next weekend, when they were easier to see as they had gone rusty. Then followed an afternoon of removing the rust stains with oxalic acid.

 

[rogerthebodger]

Not for serious work, just the odd touch-up.

There are welding helmets with a flip up welding lens with a clear lens for grinding as DownWest says for the odd touch-up.

I have a full face for long term grinding as I wear glasses for detailed work.

Lots of different ppe to suit what the OP needs

 

[KochADV]

all this talk of grinders, cutting wheels and local protection - do remember boats along side too, they'll not appreciate fine angle grinder debris in their topsides

Absolutely.. will speak to the harbour master first. The boat is normally "alone" in the corner of the harbour so can pick days with no boats alongside (usually a fishing boat now and then).

 

[Alex_Blackwood]

Looking at the photos ,it would appear that the rail is not solid but probably a U section. I am guessing this by the holes drilled in the top of the rails.
Hope for your sake that this is the case, as it will make the job a lot easier.

Surprisingly no one has suggested hiring a hefty angle grinder , at least a 150 mm wheel size. which will be big enough for the job and relatively easy to handle. Firstly I would cut vertically down the cross section of the rails to divide them into sections, about 400 long and then cut along the bottom of the outside face,as close to the deck as practical. Then cut along the back face but not all the way through, you might then be able to lever each length off ,(saves a lot of work.)
Then swap your cutting disc for a coarse grinding disc, and clean up the remaining welds, finish off with a finer disc .
Be very aware of safety ,, don't take chances wear proper gear .
Get plenty discs from the hire place, normally they will only charge you for what you use.
I have done this type of work very often ... don't envy you!


Awaiting incoming.

Bit late in post but looking at photo. Agree not solid but looks L section? Maybe wrong