Welding Tips and Tricks

Cast housing (AL) with 2 mounts with a 1/8 OD steel pin through the middle. Broke the bottom off both lugs, gap from end to end is 3/8. No way to drill new holes for pin if I completely fill exixting hole and build new lug. Is it possible to leave pin in and bridge gap with filler and build up new lugs for support after bridging the gap of aluminum over the pin? New housing is about 800.00 customer doesn't want to spend that to fix it but doesn't want to junk it. The lugs or mounts in the casting are app. 3/8 wide by 1" long. I have enough room to add all the filler I need width or length wise. Just want to know if it is worth my effort and if it is possible.

Steve - I've had some success using steel to exclude built-up aluminum. So I think what you are proposing is certainly possible.

Here is an example where I built up some aluminum around a sacrificial steel bolt. You can see where the arc struck the bolt head and fried the plating off it, but for the most part it worked very well. I was able to unthread the bolt after welding and not have to re-drill or re-tap the threaded hole afterwards, which was my original goal.

The only part that causes me concern is the small, 1/8" diameter of the steel pin you're talking about. That small of a pin if struck with the arc could pretty quickly heat and melt, which I think you'll want to avoid. So you would need to be very careful to not direct the arc directly at it I would think.

I've heard of solid carbon cylinders and blocks being sold specifically for this purpose, which might work even better than steel. Here is a link you may want to check out, although no 1/8" carbon rod is listed:
http://www.stoodyind.com/Catalogs/FISC/05catpg197.pdf

Thanks for the input.

it should work just leaving the pin in, but I'd see if you can find a piece of stainless or copper to stick in there instead of the steel pin. I've had some contamination issues welding aluminum in contact with mild steel when the mild steel is small enough to get truly hot while welding. if it were something like a 1/2" rod, I'd be less worried about contamination, so long as it was clean.

thanks for the input but the customer backed out of the deal. I estimated the job at 150.00 for three hours and said I would eat anything over that and they said I was too high.Not knowing what I was getting into with contamination and such I thought it was fair am I wrong? Sorry I don't have any pics.

nope. I'd say that's more than a fair shake. you'dve likely had 2hrs at an absolute minimum + comsumables. new wire brush, new grinding wheel, new tungsten. it adds up fast. if anything, you we're cheating yourself. some people just can't(and shouldn't) be sold. they want it done yesterday for a beer and a fiver.

ogorir wrote:they want it done yesterday for a beer and a fiver.

I know those types! Man do they get me steamed. They are best identified as early in the work process as possible, so a minimum of time may be wasted on them.

totally agree, unless it's friday and it's really going to take 15 minutes. I'll take the beer.