Thread: Can you over weld ali?

Thankis for the input people,

I ground out some of my worst welds and cleaned up with a stainless brush on a (guarded) 4" grinder all the areas that had undercut, then took my time to fill and reweld everything. It all came out alright in the end. Not the neatest of welds but looks okay for me!

I don't use a "killer" blade on my grinder. I can just see what that will lead to for me, although I know a bloke who uses them all the time. He is probably more confident with it than I am., but then again he never chopped his left thumb almost clean off with a wayward circular saw with a guard stuck open like i did, so thats his choice.

Prior to welding I clean everything with the stainless brush and then metho and on the whole have had good results, but I did use a flap disc a few times on the transom so maybe there is something in the theory they leave some crap on the site, although I did buy the discs from a weld shop who specified they were good for ali,

But I am happy with the look so far and have placed some extra braces, just because I can. Going to put the floor in this week and the side comings then it will be motor on so I will start posting pics under a new thread next week most likelu.

Chris

[QUOTE=Com_VC;1435589]At my work the first year apprentices use them without any issues

Duty of care?

As for your questions. I've seen a lot of table saws that used circular saws that had no guards fitted. Looks at chainsaws for example, they are far more dangerous but we still use them. Common sense plays a big part.

To my knowledge such table saws are no longer acceptable under work cover legislation, nor should they be.
I don't see a chainsaw as more dangerous - slower cutting speed + greater mass = slower kickback speed, allied with the greater control provided by the layout of a chainsaw's handles and the fact is the majority of chainsaws are equipped with a device that stops the chain in a fraction of a second.

Circular saws are usually big and chunky and I think the smallest blade available for them is about 160mm, I don't know how you could compare them to a angle grinder.

Hmm, lets see, circular blade - CHECK
Spins at high speed - CHECK
Has teeth - CHECK
Cuts aggressively - Check
Sounds much like a circular saw to me. /QUOTE]

Once risks and injuries were acceptable in industry, now everybody is expected to go home in the same condition in which they went to work, rightly so too.
The perceived speed of these cutters, (they are very effective at what they do), is more than offset by the potential loss of time and money caused by an injury.
Why do we need to remove ally at a far greater rate than if we were working in steel?
Using the aforementioned wax impregnated wheels or the candle wax method ally grinds far quicker than steel anyway. The amount of time one spends grinding is small compared to the overall job usually.
Why risk it?

Totally agree Karl about how hazardous these things are. I certainly wouldn't put one in the hands of a novice, trainee or apprentice. Lots of experience with regular grinders/cutters first me thinks..
Right or wrong they are however widely used in Ally fabrication shops and particularly boat building. I have used grinders all my life and these things do scare the hell out of me to use but I do use them selectively because they have advantages being mainly clean and fast. Perfect for cutting out tacks prior to welding over and I don't think it is too dangerous if used for the right situation.
Workers can just get too familiar with these things and take silly chances and there goes your face or picking up your gizzards off the floor!!
Definitely full coverup, always two hands on the thing at arms length.