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Dealing with hull pitting; confusing charging; planning for 240v; tricking the regulator
QMy narrowboat has some pitting on the waterline. Stripping the lining out would mean gutting the shower room, galley and stove area. Is there an alternative to welding on plate? I’ve heard of a method that coats by electrolysis or similar.
ATONY REPLIES... If there are not too many pits, they can be filled with weld and then ground flat. Many hulls are welded without stripping the interior. It depends upon the location and type of thermal insulation. There might not be any below the gunwales. If it is polystyrene slabs it might not touch the side of the hull – but it would be a good idea to get access, take a sample, and see if it is self-extinguishing. If it is Rockwool then welding should not be a problem. If it is spray foam, be cautious, I think it just chars a bit and stinks.
I would be very cautious about filing pits with something such as ‘plastic metal’: adhesion cannot be assured and it might be porous.
Debdale Wharf (0116 279 3034) do some form of blasting then hot zinc spraying followed by twopack blacking. In theory, all further corrosion should then stop (unless caused by electrical problems). However, if you have 6mm hull sides with 5mm pits, whatever you do with the hull you still only have 1mm of steel keeping the canal out. I would want deeper pits welded up before treatment (as I would if you went for a possibly slightly cheaper alternative of blasting, a coat or two of cold galvanising paint like Zinga and then two pack hull paint).
Deep pits need to be welded or plated