The 4130 can be gas welded. It will last longer than you will, if it is dry
inside when welded.
It is stronger than stainless in the same section.
You can wash the inside with Linseed oil and weld the hole shut when
finished. Then it will outlast all of us. You can use scrap 4130 from aircraft
salvage.
You can fix it anywhere there is a gas torch. Not just a TIG set. Rare at
little airports.
Check the Dillsburg aeroplane co. In Dillsburg Pa. for best new
prices.
Thanks for the comments
Lynn. I only have TIG to weld with, and the gyro won't be traveling
unless it's on a trailer, so weldability isn't an issue. I did figure that
4130 was stronger, but don't know if it's enough to matter, particularly since
I'll be probably using 2-3 times the size I really need.
Fortunately, the quantity I need is so small that I won't be shopping around for
price. I'll just order from McMaster Carr, and have it next day via UPS
ground. Gotta love the way that works :-)
Cheers,
Rusty