New windows in steel boat. Need welder.

[Roadkill]

Hello,

My boat survey revealed some leaks and rusting around the windows. The windows aren't the best design and it's likely to happen again if repaired, so I'm looking at getting new windows made - possibly from Houdini Marine. I'm thinking of cutting out the whole sections of steel with the old windows on and having new steel precut with window apetures. Can anyone reccomend a welder/shipwright in the Hull area who could do this work? The boat is in the yard at Hull Marina.

Thanks in advance,

Dave.

 

[PCUK]

If the plating is not too thick - say 4 - 5mm, you can do the job yourself quite easily with a good quality pendulum jig-saw. I cut many apertures in my boat using one on 4mm plate. Use quality steel cutting blades and you will be pleasantly surprised.

 

[Roadkill]

It's only 3mm, but I'd be too scared to attempt it myself.

 

[AndrewB]

This seems a very radical approach. Why don't you just cut out the old windows, treat the rusty steel, and get replacements to fit the existing apertures?

The world is full of welders, just ask around. Its MUCH cheaper to engage a private guy than go to a big company or yacht yard. The job you describe doesn't require great skill. Check first with the marina though, most have very strict rules about having welding done, because of the danger and the mess.

 

[Roadkill]

I think I might be going down that route now, resealing the existing windows, to save time and money. The survey came up with some areas of the 3mm super structure being perforated though. Should I be able to get a welder to patch those areas up easily enough? Before all this I'll be getting her shot blasted and primered which should should show up any badly corroded areas, on the outside at least.

 

[AndrewB]

You must treat the rust under the window frames, of course, its just a waste of time to patch this up around the outside as the rust marks will reappear almost immediately. If the windows are aluminium framed you will be lucky to get them off intact, as the rust implies galvanic erosion has been taking place. However, if you can, there are places that will refurbish them for you. Otherwise, a small made-to-measure fixed window in an aluminium frame is going to cost upwards of £150.

It may not be strictly necessary to go for a total shotblast of the deck. Where the paint looks sound, neither rust stained nor raised in a blister, then the chances are high that there is no rust problem underneath. It is an idea to clean up the rust stains a bit with dilute oxalic acid ("Starbrite"), as often the damaged area is smaller than it seems at first sight. Most deck rust problems occur around fittings (specially of wood or aluminium), and in awkward corners that good yacht design should minimise.

You will certainly want any perforated area rewelded. It should be downhand welding, so not difficult. The only advance preparation is to remove everything flammable from anywhere within several feet of the place to be welded. This may mean getting down the headlining and roof insulation inside the yacht. You don't prime until afterwards, as the welding will simply burn it off!

Best would be to have the affected part neatly cut out and a new piece of steel welded in. It is a lot simpler, and so cheaper, to weld a patch over the affected area, and with care this will scarcely be noticeable after repainting. Another possibility, which was advocated for small holes by several others on another recent thread, is to patch the damage with epoxy filler after it is first derusted and primed. I don't like this myself, except as a temporary solution.