Welding cast iron with O/A?

[874crawler]

I did a search and it seems like the welding cast topic has been beaten to death but I haven't seen any threads about welding cast with O/A. All the threads I have read are saying stick or tig with 99nickle rod.

I have a stock cast manifold for my cummins diesel and I want to weld a short piece of steel tubing to it to adapt an external wastegate to it.

My thinking was drilling/machinging a hole in the manifold the size of the ID of the tube and beveling it so the tube has a nice fit and I was wondering if I could weld it with my O/A torch and a 99nickle rod?

[ArgonWelding]

You can do it if there are redeeming qualities left in the cast. Problem is every single cast iron exhaust manifold I have ever touched has not had anything to weld to. All the weld does is blow out. Your best bet is to machine the hole so your tube fits into the hole. Not a press fit, give it about .005 clearance. Instead of welding, try brazing. You will get your seal and you wont ruin your manifold.

[LarryO]

Originally Posted by 874crawler

I did a search and it seems like the welding cast topic has been beaten to death but I haven't seen any threads about welding cast with O/A. All the threads I have read are saying stick or tig with 99nickle rod.

I have a stock cast manifold for my cummins diesel and I want to weld a short piece of steel tubing to it to adapt an external wastegate to it.

My thinking was drilling/machinging a hole in the manifold the size of the ID of the tube and beveling it so the tube has a nice fit and I was wondering if I could weld it with my O/A torch and a 99nickle rod?

I'm sure Castweld(Peter) will read this soon.

Try looking up his threads. He is the resident expert here on welding cast. ( i know other people can do it successfully )

[gizzardgutz]

The few times I've seen OA used with cast iron has been exclusively brazing. Not that it can't be done, I'm just familiar with it, and I've been around awhile.

[874crawler]

Brazing. Yes. Isn't that what I am talking about? Joining the two pieces together using a nickel filler rod?

[woof]

In welding you melt the filler rod and the parent material.

[DSW]

No. Brazing uses a brass filler usually. It's much like soldering as the iron does not melt and you use a flux. It's done at much lower temps than welding.

With nickel filler you are truly welding. Both the filler and the iron melt and mix.

[874crawler]

Okay, I am new to this.

Which would be the better way to go then. Its possible that this will see pressure possibly around 80psi and temps up to 1700º



What I was thinking is I would be heating the two pieces to red hot and then applying the nickel filler

[castweld]

1: OA is best method to weld, but get cast iron fitting and weld with cast iron filler. Requires lots of pre/post heat.

2: OA powder spray weld will weld dissimilar metals and requires lower pre/post heat.

3: And yes on a new manifold with some pre/post heat -nickel stick, tig, or mig will make an acceptable weld.

4: Braze may work but bronze will soften with high temps, If you are working with performance motor ex temps will be high.

I prefer #2 because of lower pre/post heat.
Although #1-hot welding is most reliable--Heat required for CI filler is over 1100 degrees and can cause warping and need to remachine all surfaces. Also what few know is that a casting at 1100 will expand and not return to orig dimensions when cool.
PM me if you have questions.
Peter

[874crawler]

I may have to find someone to powder spray weld it then because I don't have the equipment to do so

[Grandi]

Crawler,

Don't know where you're located, but I'm out of Harrisburg PA. I have the set up to Spray weld your manifold. I use a Eutalloy B torch with a Nickle based powder. Works pretty slick. If you're interested, leave me know.

Thanks,

Grandi

[874crawler]

How much did the torch run you and where did you get it?

Im out in California

[Grandi]

I work for a company called Dyeco Inc www.dyecoinc.com . We sell these torches along with the powder. The torch runs 650 bucks and I'd have to check on the pricing for the Powder. If you're interested in anything, leave me know. Torches are in stock. Very simple to use. My email is mgrandi@dyecoinc.com if you want more info.

Grandi

[874crawler]

Thanks for the info. Seems like a good price if I was doing a good bit of cast welding but I don't see myself doing any more after this one.

Who know's though, maybe I will get one just for the heck of it.

What other applications is powder spray welding good for?

[Grandi]

There's a ton of applications man. You can do hardface overlay with it, along with dissimilar steels. I works slick for build-up work too. I've used it alot for cracked Cast housings. Here's pic of a before and after of a crack I repaired. The gap at the bottum was a 1/2".



And here's a Manifold that we built back up. Pretty Slick.

[castweld]

874crawler
I bought a spare powder torch on ebay for $125 and it came in a kit with cutting head, and welding tips plus 12 lbs of different types of powder. Nickel powder goes for 30 to 80 bucks a pound, depending who you get it from.
Or prep it box it and ship to me and I'll weld in oven for $80 plus shipping.
Peter

[874crawler]

Would you be able to do it without it warping or expanding?

[castweld]

Originally Posted by 874crawler

Would you be able to do it without it warping or expanding?

I try.
Peter

[DougAustinTX]

Not trying to interfere with the free flow of commerce here, but couldn't you just drill the manifold and use a pipe tap to thread it, then put a threaded fitting for the waste gate with some high temp anti-seize?

[874crawler]

I didn't even think of doing that but I think it would look kind of hokey if it was just threaded in. Plus I don't have a tap that big

[874crawler]

Originally Posted by castweld

874crawler
I bought a spare powder torch on ebay for $125 and it came in a kit with cutting head, and welding tips plus 12 lbs of different types of powder. Nickel powder goes for 30 to 80 bucks a pound, depending who you get it from.
Or prep it box it and ship to me and I'll weld in oven for $80 plus shipping.
Peter

Well I just won a powder torch on ebay. Im not sure if its complete or even the right torch but I won it for 28 bucks:

http://cgi.ebay.com/ws/eBayISAPI.dll...9#ht_500wt_967

[Grandi]

That torch was designed to do buildup on shafts.Spraying is typically done in a lathe as it turns. Can't beat it for 28 bucks though. Eutectic's version was the Rototech Torch.

Grandi