Farm TIG Welding (Part 1)

After a few month of TIG welding practice I’ve taken on my first “real” project. One big change since the last post, I have started using a foot pedal instead of a hand control for the current control, this has made a huge difference in my ability to smoothly start and stop a weld. I strongly recommend it over the hand controls when the application allows it.

I am making a walk behind flame weeder with a stainless hood. While there are many different ways to make or buy one, I decided to make just about as much as I could, manually. First off, a sheet metal brake would have been ideal, it turns out 16 gauge stainless sheet metal is pretty hard stuff to bend without a massive multi ton brake, so I decided to cut and weld the bends of the hood . The hole for the torch heads were drilled into the stainless using the nicest carbide tipped hole saw $15 will buy on Amazon. This was a long process and was done on a drill press (outside) with lots of cutting oil, smoke, and breaks.

The gas manifold was made from 1-1/2” stainless square tubing about 0.080” thick, the easiest thing to do would be to have purchased some iron pipe and threaded everything together. I decided to Make a manifold instead, it would be more sturdy and made an excuse to weld in threaded bungs. Turns out those are harder to weld in than expected, I learned this 6 times over on this project. Keeping an even torch angle, feeding filler, and realizing you’re running out of space was hard. The end caps were just 16 gauge stainless sheet, precision cut with an angle grinder, and like everything else wiped down with acetone before welding.

The hood was tricky to line up without the proper jig. I improvised with random items on the uneven bench and a few bar clamps. I started by tacking the top piece to the front/back edge every 4”-6” without filler. I I originally tried using filler on the first pass, 1/16” 309 rod, and made it harder than it had to be. Then I just moved on to just doing a fusion weld, sliding down the 36” using a TIG finger to keep the digits cool and made the motion easier.

After all was said and done, I took a wire wheel to the welds to clean off the color and see the true weld at the end of the day. I think the bung welds look better when they aren’t dark shades of stainless discoloration. The downside is that you see every inconsistency and mistake when the pretty colors are gone.

Part 2 will be the rest of the walk behind unit including the propane tank holder.

Enjoy