TIG welding first attempt..

cathead

CATWERKS LTD
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Someone(previous owner) beat on the fuel cap on my D4 Cat dozer and broke off one of the tangs. It was my first attempt at
AC welding using the TIG. I can see there is a learning curve for this type of operation but one has to start somewhere.
I just dialed in the upslope, downslope and welding amps along with the pre and post flow gas times and proceeded to burn
off the tungsten! The welding looked pretty cruddy so really don't know what I was doing wrong. The second attempt went a
lot better with less welding amperes. Anyhow, after grinding off the excess and using up a couple 2 inch roll lock discs to clean
the weld up, I was surprised that it looks as good as it does.

At any rate, that's what I did in the shop today. It actually got above freezing with some sunshine so was able to be outside
some and enjoy the day too. P1020674.JPG
The tang on the left is the one I added weld to. The base metal didn't want to melt much but the rod (1/16 inch diameter) melted anywhere
close to the plasma arc. I can see larger rod would have been better but that is all I had in the shop today. For a first attempt, I was happy
that I didn't have to get out the oxy-acetylene welder to finish the job. I was using 2T with the finger tip control as it looked easier for a first
attempt. I would have to say that part of the problem was the thin rod and the rest was improper setup likely. The weld looked to have a lot of
oxidation on the surface so need to use more cleaning action on the welder and maybe surface prep as well. I did grind it clean with a stainless
brush as well. Any advice on settings for this weld job would be appreciated. Thanks all for watching.

One other thing, the garage door opened all by itself while welding attesting to the fact that TIG generates a lot of radio frequency hash.:frown:
 
I'm not a welding expert but I can say this, Your metal needs to be CLEAN! Most likely there is diesel fuel leached into the casting of the cap, that will make it very difficult to weld.
 
Just curious... what material is that cap made from? Use AC for aluminum and DC for other metals. I've found from my limited experience that aluminum welding is more difficult than steel. And yes, any kind of material must be very clean for TIG welding, especially AL. I clean it with a SS wire brush (only used on AL) and wipe the base metal and the filler rod with acetone. Rough rule of thumb, set your machine for 1 amp per 0.001 of base metal thickness. Set it a little higher and control it where needed with your foot pedal.

There are a lot of YouTube videos you can watch that will get you started on the right foot...

Ted
 
As Ted said why AC. unless the cap is aluminum. Al
 
Just curious... what material is that cap made from?

It is aluminum or aluminum alloy of some sort. I'm using an Everlast 210 EXT on 220 volt supply145 amperes and 3/32 2% lanthanated tungsten.
 
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I am always surprised when I switch to aluminum how much extra current it takes than steel.
I believe it is just more thermally conductive and the heat runs away quickly....

Therefore, I like to use the pedal with Al so that I can "floor it" to get the puddle started, then mostly "coast" when the work piece is up to temp.

the garage door opened all by itself while welding attesting to the fact that TIG generates a lot of radio frequency hash.

Good for ventilation, not so good for the temperature and breeze!

-brino
 
You're awfully brave trying to do a repair on 1st experience. I practiced for hours (read that 'burnt up both metal scrap and consumables) before ever touching a real part.
Go for it and have fun!
Aaron
 
Welding on a piece of aluminum like this would be a pain in the butt. It will have soaked up fuel and make it very difficult to get it to stop boiling out impurities.
Like was said earlier, it takes a lot of heat also.
Joe
 
Also, I didn't see you mention having a foot pedal to control your heat. On aluminum you need a huge amount of heat at first to get everything hot. Then when you start to get some puddle going have to back down to keep from melting through. It can be kinda fickle until you get the hang of it.
Also some alloys just don't weld very good.
Joe
 
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