which welding rod?

[3RRL]

</font><font color="blue" class="small">( I found a 1" long crack at one of the welds)</font>

All welds create stress on the parent material and if the ends of the crack are not pooled through, it may migrate further under stress from usage.
Besides "V-ing" out the crack, I've had great results with drilling a hole at the end of the crack to keep it from migrating further, removing a "sharp edge" there. Then weld the hole shut with circular welds and follow with filling the crack itself.
As for welding rod, use what you can handle to get good penetration and strength with as little heat as possible. This helps the overall strength of the weld and parent material. When selecting rods that are close close in tensile strength, I'd opt for better weld preparation and a rod that will give me penetration.
I's like the old golf commercials advertising Beryllium copper irons for "soft" feel. There is a diference on the Rockwell Hardness Scale (Rc), but you really can't tell the diference from hitting a golf ball.
Personally, I use my 330A Miller TIG welder with 410SS rod, Ø1/16 for repairs. That rod mingles well with most all metals from mild steel to tool steels. The weld comes out clean as a whistle. I realize most guys don't have a TIG in the shop so that may not be an option.
But like so may others said before me, prepare that weld area real good.

 

[tswirka]

a 1/8 6010 and 3/32 7018 both run at the same amps 75-100.
i like to run @ 80-85 amps, any hotter and the weld puddle is harder to control. drill the ends, grind out the crack grind deep if its a deep crack, just dont go through, and put a pass of 6010 in there to penetrate and fuse the crack. grind that a little or just brush the slag of and fill and cap with 3/32 7018. multiple passes not just one big one. chip and brush between passes and VOILA'. yer a welder.
good luck, just do it(practice a little first)
Todd

 

[bjr]

Great subject. I've the very same questions. One thing I'm needing is there a price deal on rod online somewhere? I paid $3 a lb for 5 lb 3/32 6011 locally and felt like I got hosed. $15 for a hand full of mild steel rod is ridiculuos I think. I've searched but haven't found any good online vendors, any recommendations? bjr

 

[_RaT_]

I would do it as tswirka says. That has been my experience as well. A 6010 root pass and 7018 for the fill in as many passes as it takes.

 

[ALABAMA_KID]

Not cheapest but better.
Lowes 6011 5lbs $8.00 10lbs 16.00 ..

local welding shop 50Lbs about $63.00

Hope this helps..

 

[Diesel_Boy]

home depot. 5 lbs 6011 - $8.00