What filler rod to use?

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EOsteam
Posts: 240
Joined: Thu Jan 31, 2013 1:33 am
Location: Pendleton, Oregon

What filler rod to use?

Post by EOsteam »

I'm going to have to weld a cast iron piece and some 1018 steel together. What filler rod should be used and are there any special procedures that need to be followed? I'm set up for TIG.

Thanks,

HJ
Carm
Posts: 457
Joined: Fri Jan 18, 2008 5:14 am

Re: What filler rod to use?

Post by Carm »

Informed response requires intended mechanicals and thermal gradients.
What purpose does the weldment serve?
EOsteam
Posts: 240
Joined: Thu Jan 31, 2013 1:33 am
Location: Pendleton, Oregon

Re: What filler rod to use?

Post by EOsteam »

The cast iron piece is bored to accept a "lightly" pressed shouldered cylinder. The blueprints call for 4 stitch welds to lock the pieces together. I believe the welds are there to prevent the cylinder from being "unpressed".

HJ
Carm
Posts: 457
Joined: Fri Jan 18, 2008 5:14 am

Re: What filler rod to use?

Post by Carm »

Without further comprehension on my part, stitch welds on cast iron are very poor practice.
The reason, rapid chilling guarantees cracks.
Yes, there are procedures to avoid that
But alternate methods may be preferable...anaerobic lockers, mechanical (pins, dutch keys etc.)
If the part is not greatly stressed in withdrawl you could "weld" it with silicon bronze and TIG.
Hard solders would also work...no stress risers.
But then you couldn't have a press fit unless you provided a "key" (like an annular groove)
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warmstrong1955
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Location: Northern Nevada

Re: What filler rod to use?

Post by warmstrong1955 »

Carm wrote:Without further comprehension on my part, stitch welds on cast iron are very poor practice.
The reason, rapid chilling guarantees cracks.
Yes, there are procedures to avoid that
But alternate methods may be preferable...anaerobic lockers, mechanical (pins, dutch keys etc.)
If the part is not greatly stressed in withdrawl you could "weld" it with silicon bronze and TIG.
Hard solders would also work...no stress risers.
But then you couldn't have a press fit unless you provided a "key" (like an annular groove)
Especially true with TIG, as the heat is more concentrated than with MIG, or especially stick. .
If you do weld....
Get some nickel filler rod. Best chance at not cracking along the cast iron as it cools.
Preheat the parts after assembly. About 400-500 degrees should do it.
You will need to preheat it evenly! I've often used an oven for small parts.
Weld, and immediately stress relieve after each bead.
Stress relieve all the beads again after welding. Peining with a dull slag pick will work, but a needle scaler will work a lot better. Small beads, you can remove some of the needles so you don't beat other things to death. An air regulator helps too, for delicate work.
Cool slowly, and pein occasionally as it cools. You can do that in the oven, or, preheat a bucket of floor dry, and stuff it into that. Or....both.

Bill
Today's solutions are tomorrow's problems.
EOsteam
Posts: 240
Joined: Thu Jan 31, 2013 1:33 am
Location: Pendleton, Oregon

Re: What filler rod to use?

Post by EOsteam »

What about silver soldering? Is that what is meant by "hard solders"?

HJ
b4autodark
Posts: 51
Joined: Fri Dec 16, 2016 9:06 am

Re: What filler rod to use?

Post by b4autodark »

I don't have any posts here so I probably have zero credibility but I do have 40 years experience as a welder so here goes. I would weld it with the TIG process using silicon bronze as filler rod, this would work best for dissimilar metals, which I do a fair amount of. If you don't have TIG capabilities I would stick weld it with 316L or 308L stainless steel electrode at 3/32" diameter at about 90 amps using reverse polarity. Just my opinion based on what has worked for me over the years. Pre and post heat and stress relieving would also be beneficial.

Good Luck,
Jeff
hammermill
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Joined: Sun Jun 27, 2010 10:43 pm
Location: pendleton or

Re: What filler rod to use?

Post by hammermill »

i would consider both the silica bronze with tig or the stainless rods. either would call for preheat and a slow cooling. like ashes in the woodstove or the preheated floor dry in a hot oven. unless you want to buy your bride a new over consider snaging a used unit from behind western auto. use it and return it when done.
b4autodark
Posts: 51
Joined: Fri Dec 16, 2016 9:06 am

Re: What filler rod to use?

Post by b4autodark »

Have you done this project yet? Just wondering the outcome.
EOsteam
Posts: 240
Joined: Thu Jan 31, 2013 1:33 am
Location: Pendleton, Oregon

Re: What filler rod to use?

Post by EOsteam »

I have to run to Norco to see if they have any Silicon bronze rod. This is a small town, I wonder what the chances are they will have it?

HJ
JackF
Posts: 1616
Joined: Mon Jan 26, 2009 3:56 pm
Location: Caldwell, Idaho

Re: What filler rod to use?

Post by JackF »

If they don't try Airgas, the store in Caldwell, Id. had it. :)



Jack.
shorttrackhack
Posts: 42
Joined: Sun May 15, 2011 4:38 pm
Location: SoCal

Re: What filler rod to use?

Post by shorttrackhack »

I've TIG welded cast iron with nickel 59 and 99, as well silicon bronze many times. These fillers always leave a noticeable color difference from the original iron, as they don't rust (really only important on restorations). For the last several repairs, I have been using old piston rings from small block Chevy engines. The welded areas rust orange and finish nicely. My favorite part is that old rings don't cost $50.00/lb...
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