lower units...skegs

[blackwire]

I'm new to aluminum welding and am doing a few skeg jobs.What do you use to sand paint off and bevel pieces to be welded?(without contaminating the aluminum).

[Hardrock40]

I'd say pretty much anything you want to use. You can run your disk across a wax candle to keep it from loading up to much.

Personally I wouldn't worry about contaminants on a skeg. Your most likely going to see black crap floating out of the base aluminum.

If the lower unit still has the prop shaft and gear housing seals in it that would be more of a concern. Use high heat to get the weld going quick and let it cool some when it gets hot. Maybe some wet towels will help cool the gear housing.

[blackwire]

Yeah I was wondering what to use..my aluminum oxide flappers embed the aluminum(I wax them too),I found 3M surface conditioning disks work.Just looking for some tricks here.How about cutting the skeg material and the lower unit..I use my plama on thr cast,but saw cut the blanks...any thoughts?

[Bistineau]

There are grinder discs made specifically for aluminum you could try instead of the flap discs. These do not load up like the standard type disc do. Check at your LWS for them, someplaces you may have to ask them about it as they don't always keep them out on the shelf.

[MMW]

A carbide bit in a die grinder can also work depending on the application.

[sturugged]

Hello, I have had good luck using flapper or sanding disks to remove the paint off the lower units. Once the paint is gone , regular grinding wheels or zip-cuts with bees wax to stop them clogging up for grinding or cutting the base aluminum. As for cutting the new patch pieces or material , I use a small wood cutting bandsaw for making up patch pieces or shape cutting, its alot cleaner cut than the plasma and there is no cleanup required, before welding it. You can even bevel your pieces nice if you want to get real fancy. For just breaking up the oxide layer and between passes i use a blue Walter stainless steel wirewheel on the grinder for buffing off the welds. This works good if you do get the black junk contamination . hope this helps