Cast differential truss

[chopfab]

I have a Question about cast.I am building a rock crawling buggy and it has dual triangulated 4-links front and rear.Should I stick weld the trusses with High nickel electrodes,or Tig them with Silicon bronze ?I have been told both , but I am not familiar with these metals.I know I must preheat,but If you are familiar with these procedures ,please explain how I should go about this in detail ,and what electrode or filler metal to use.Thanks in advance!

[MicroZone]

What is the axle out of? Have you attempted a spark test on it? It could be cast steel, cast iron or basic junk (import) metal.

[chopfab]

The rear is a chevy corporate 14 bolt full floater,The front is a dana 60.I Would think they are nodular iron centersections , but I am not sure.No I have never heard of a spark test ,I am 200 miles out in the gulf of mexico at the moment .I'll be home on the 9th to do the test if you can explain how,someone might know the answer before I get home.

[rusty ripple]

http://books.google.com/books?id=6gP...RA1-PA8-IA4,M1

page 68

[goose-em]

I believe that both axle pumpkins are made from cast steel. Very , very doubtful they would be made from cast iron as it would be extremely brittle and prone to failure.

As such, I would recommend welding with good old fashioned 7018 stick if that is what is available. You could also use FCAW or GMAW or GTAW all using plain carbon steel electrodes.

I wouldn't worry about preheat on your application, I take it that you live in a gulf state and right now that metal ought to be well preheated for it's thickness.

[reddoggoose]

As long as the trusses are cast steel then I agree with Goose-em, weld it up with a Lo-Hy electrode, GMAW or TIG, all of which are low hydrogen processes. As long as the carbon content in the casting is low, a preheat won't be necessary.

If the trusses are cast iron go with the high nickel rod, preheat, and slow cool.