[TraditionalToolworks]

Just pinging for some advice on this, I don't have a lot of these flange nuts, so hope not to destroy them.

The flange nuts are stainless, about .075" thick, and the tube is mild steel about .090" thick.

I haven't done a lot of stainless, but in the past I've used about 2/3rds the amps, so I would probably use about 55 amps for the stainless. What I'm not sure of is if I need more amps to penetrate the mild steel tube, normally I would use about 85-90 amps for that. When you're welding stainless to mild steel how do you balance out the amps?

I plan to use a bolt in the nut while I weld it, it's a 3/8-16 thread and the hole is 1/2". I will clean everything with acetone, so ignore the sharpie marks.

I plan to use 1/16" tensileweld tig rod which is suggested for dissimilar metals.

What amps would you guys recommend?



This is how I will weld it on top of the hole. It's for an axle bolt on a welding cart.



These are the axle components, a thin dry bearing over the axle, a washer and the flange nut. I have another lock washer for the outside which I bent flat, so the size works out for the width of the wheel.



What it will look like, the thread will go in the center of the 1/2" hole, the thread is 3/8".

[kiwi2wheels]

Run a file over the hole to remove the burr from the counter sink so the flange is in full contact with the tube.

[cj737]

And use some anti sized on the bolt thru the stainless when welding it. Else you may find it fused permanently.

[BillE.Dee]

I just finished. a project that is similar (not stainless),,,didn't give anti seize a thought and had to "coax" a bolt out of a nut. got it out and ended up running a rethreading tap. I will remember cj's suggestion next time.

[TraditionalToolworks]

Run a file over the hole to remove the burr from the counter sink so the flange is in full contact with the tube.

Yeah, I will clean things up and use a 2" scotch brite pad on a die grinder on the tube.

And use some anti sized on the bolt thru the stainless when welding it. Else you may find it fused permanently.

That's a good tip, I've never done that and find I need to remove the bolt while it's still warm so it doesn't fuse, and I have screwed the threads up in the past with too much heat...

So tell me, if I can pick your brain, how do you approach something like this where you have a thinner piece of stainless on a heavier piece of mild? I guess I'm looking for 2 areas. 1st the difference between the amps needed, seems you would need to use the higher amps in order to penetrate the mild tube in this case. The 2nd area, if you would do that would you focus the arc on the mild tube and try to keep it away from the stainless flange nut?

As I think this out I guess it makes sense to focus on the mild steel, so maybe in that case start the puddle on the mild and move it up to the edge of the stainless??? Trying to understand how a real welder would approach it.

[Spartan]

Run a file over the hole to remove the burr from the counter sink so the flange is in full contact with the tube.

Yeah, I will clean things up and use a 2" scotch brite pad on a die grinder on the tube.

And use some anti sized on the bolt thru the stainless when welding it. Else you may find it fused permanently.

That's a good tip, I've never done that and find I need to remove the bolt while it's still warm so it doesn't fuse, and I have screwed the threads up in the past with too much heat...

So tell me, if I can pick your brain, how do you approach something like this where you have a thinner piece of stainless on a heavier piece of mild? I guess I'm looking for 2 areas. 1st the difference between the amps needed, seems you would need to use the higher amps in order to penetrate the mild tube in this case. The 2nd area, if you would do that would you focus the arc on the mild tube and try to keep it away from the stainless flange nut?

As I think this out I guess it makes sense to focus on the mild steel, so maybe in that case start the puddle on the mild and move it up to the edge of the stainless??? Trying to understand how a real welder would approach it.

I'd set the amperage for what you'll need on the mild steel, and just focus the arc more on the mild steel and let the puddle just barely wick up to the stainless. If that gives problems, I'd then try doing a bit of a weave where I shift the arc between the stainless and the mild steel as I progress, but keeping the arc on the mild steel for two to three times as long compared to the stainless. I'd just let the arc "kiss" the stainless for a fraction of a second during the weave pattern, if that makes sense. You can also pump the pedal a bit to lower and raise the amperage as needed as you weave between the two materials.

But I think the first method (no weave) would probably be the way to go.

[TraditionalToolworks]

I'd set the amperage for what you'll need on the mild steel, and just focus the arc more on the mild steel and let the puddle just barely wick up to the stainless. If that gives problems, I'd then try doing a bit of a weave where I shift the arc between the stainless and the mild steel as I progress, but keeping the arc on the mild steel for two to three times as long compared to the stainless. I'd just let the arc "kiss" the stainless for a fraction of a second during the weave pattern, if that makes sense. You can also pump the pedal a bit to lower and raise the amperage as needed as you weave between the two materials.

But I think the first method (no weave) would probably be the way to go.

Yeah, this is good food for thought, thanks for the response.

That is how I was thinking about it, where I would kind of just let the puddle kiss the edge of the stainless like that. I hadn't thought about doing a weave pattern on it but that does make sense to lower the amps as you bring the puddle on the stainless. Of course in that case you need to be doing the weave in order to utilize the pedal like that.

I'll try the first method and see how that goes after I get some of my work out of the way...(I might be able to sneak out to the garage during the day).

[Spartan]

I'll try the first method and see how that goes after I get some of my work out of the way...(I might be able to sneak out to the garage during the day).

What's your day job?

Also keep in mind that that little flange/bung will get hot QUICK, so you may need to do the welding in halves or thirds, and let the part cool for 5-10 mins in between. Putting a small fan on it will help speed that.

[TraditionalToolworks]

Also keep in mind that that little flange/bung will get hot QUICK, so you may need to do the welding in halves or thirds, and let the part cool for 5-10 mins in between. Putting a small fan on it will help speed that.

Yeah, that I do know from experience. My plan is to put one small tack on each side, then weld one end at a time and split the sides up between 2 welds each. Although tacks would probably hold it fine, my concern is water being able to get in. The same reason I ended up sealing all seams on the frames.

In the past I've welded stainless hex nuts on for a similar use, but they're quite a bit thicker, and yes, they do get VERY hot.

[tweake]

one of the common tricks i like to use is to clamp a bit of aluminium on the stainless as a heat soak.
however make sure its clamped down. i have had it where the stainless warped a bit which lifted the aluminium off it and it went all to crap.

[Poland308]

Your going to tig them with 309, right?

[TraditionalToolworks]

one of the common tricks i like to use is to clamp a bit of aluminium on the stainless as a heat soak.
however make sure its clamped down. i have had it where the stainless warped a bit which lifted the aluminium off it and it went all to crap.

I've thought about it but not sure I can get access if I put a piece of chill bar on top, I might be able to get a small chunk on there. I could probably add a couple small chill blocks to the side of the tube.

Your going to tig them with 309, right?

More like 312 if I understand correctly, similar to Harris Super MissleWeld.

This is what I'm planning to use, it's called Tensileweld,

https://weldingwire.com/Images/Interior ... ig-tig.pdf

https://weldarcgasandsafety.com/product ... -tig-wire/

[Spartan]

This is what I'm planning to use, it's called Tensileweld,

https://weldingwire.com/Images/Interior ... ig-tig.pdf

https://weldarcgasandsafety.com/product ... -tig-wire/

Seems like an interesting filler. I'm curious why you're using a boutique-ish filler like that, though.

[TraditionalToolworks]

Seems like an interesting filler. I'm curious why you're using a boutique-ish filler like that, though.

Because I have it.

I don't have any 309, only 308.

It's actually a good filler to have, it's intended for welding of indifferent metals like stainless/toolsteel, stainless/mildsteel, mild/cast, etc...and it's not actually boutique, it's fairly common in aerospace, certainly places like NASA which is who my LWS sells it and Harris Super MissleWeld to. My LWS says it can weld any metal together, no matter what it is, and if it can't then it's not possible to weld it.

[Coldman]

That wire will work very well.

[Spartan]

Seems like an interesting filler. I'm curious why you're using a boutique-ish filler like that, though.

Because I have it.

I don't have any 309, only 308.

It's actually a good filler to have, it's intended for welding of indifferent metals like stainless/toolsteel, stainless/mildsteel, mild/cast, etc...and it's not actually boutique, it's fairly common in aerospace, certainly places like NASA which is who my LWS sells it and Harris Super MissleWeld to. My LWS says it can weld any metal together, no matter what it is, and if it can't then it's not possible to weld it.

Might have to pick me up some. Seems like good stuff. I also like how much they stress that it is non-cracking. That MAY be useful for me when I massage my tacked-up parts just a little too much when getting things aligned/squared. Probably not at all what they intend as far as "non-cracking" goes, but hey, if it's just a tiny bit more ductile/forgiving, it may be beneficial to me in some of those scenarios.

[TraditionalToolworks]

Might have to pick me up some. Seems like good stuff. I also like how much they stress that it is non-cracking. That MAY be useful for me when I massage my tacked-up parts just a little too much when getting things aligned/squared. Probably not at all what they intend as far as "non-cracking" goes, but hey, if it's just a tiny bit more ductile/forgiving, it may be beneficial to me in some of those scenarios.

It's definitely good to have on hand, if not else but a last resort, for those very unusual tasks where the metals are different.

Once in the past my LWS gave me some Harris Super MissleWeld rods to weld some stainless hex nuts to mild. Later I found out they made tig filer, so when I was over there I asked them if they had any. I had never heard of Tensileweld, but they had a case of it and sold me a pound out of it and he told me it was the basically the same as the Harris Super MissleWeld. He had told me before that HSMW was pretty much 312, which is why I mentioned that here.

And you're absolutely right about the cracking, because my understanding is that's exactly where the failure happens on welding different steels together. This is also like 122,000 tensile strength.

I didn't get out to the garage yesterday, but going to try to get out there soon.

[TraditionalToolworks]

Best tips in this thread were cj's recommendation to use anti seize in the threads while welding, that saved me. Just as a data point, the anti seize is good for up to 1600 degrees and the flange nut get to about 325 degrees on one of the long sides. Normal temp is the shop today is about 88. I have an infrared thermometer, so it's pretty accurate. Surprisingly the actual grade 8 nut I had in it and the stainless nut got the hottest, and weld cooled down quickest. On the side of the tube was hot up near the top of the side, but down about halfway the metal almost dropped down to room temp.

I tried to stay on the edge of the flange nut, but this pic show I had plenty of filler...

[Spartan]

Looking good! Been waiting for you to share some pics!

Can you post a link to the anti-seize you used??

[Spartan]

Also... Was welding some tool steel splines to stainless round stock today, and thought "dang, I could sure use that tensileweld rod TTW was talking about, bet that would be perfect for this". Definitely going to pick some up now.

[TraditionalToolworks]

Looking good! Been waiting for you to share some pics!

For certain your welds will look better than mine...

Can you post a link to the anti-seize you used??

I used Permatex, got it at O'Reily's Auto.

Permatex Aluminum Anti-Seize 81343

It actually is for Aluminum, but it was the only anti-seize they had...says -60f - 1600f

They have one for nickel when I was looking online, it's good up to 2400f, metal will be meting at that point, seriously, mild steel melts at about 2300f. The nickel one is 77124, get that if you can.

All of them are that messy silver $#!T that gets all over everything, even with a small dab. I was so careful to add it to the threads and screw the bolt in all the way, even wiped it off and cleaned it, but still go some on me anyway. At least I didn't end up looking like a martian.

RE: Tensileweld, it seems to flow really nice, not that I could really tell, but it seems to flow better than ER70S-2/ER70S-6.

[BillE.Dee]

Also... Was welding some tool steel splines to stainless round stock today, and thought "dang, I could sure use that tensileweld rod TTW was talking about, bet that would be perfect for this". Definitely going to pick some up now.

spartan, do you suppose just asking for 312 will get you the tensileweld or are the two not synonymous????

[Spartan]

spartan, do you suppose just asking for 312 will get you the tensileweld or are the two not synonymous????

I had seen somewhere (probably here) that it may be the same as 312...but I don't know for sure. Either way, tensileweld's marketing people did a good job of getting me to choose it over 312

Just picked up a pound of it in 1/16" which is my "I can make this work on almost anything" rod size of choice.

[LtBadd]

I had seen somewhere (probably here) that it may be the same as 312...but I don't know for sure. Either way, tensileweld's marketing people did a good job of getting me to choose it over 312

Just picked up a pound of it in 1/16" which is my "I can make this work on almost anything" rod size of choice.

I saw on ebay it's $18 per pound, not a bad price. I paid a similar price for 1/16" er312 locally

[Spartan]

I had seen somewhere (probably here) that it may be the same as 312...but I don't know for sure. Either way, tensileweld's marketing people did a good job of getting me to choose it over 312

Just picked up a pound of it in 1/16" which is my "I can make this work on almost anything" rod size of choice.

I saw on ebay it's $18 per pound, not a bad price. I paid a similar price for 1/16" er312 locally

I looked around online...didn't see a whole lot of options. Ended up getting it for $19/lb from the link TTW sent. They seemed reputable and had a paypal checkout option which made it fast and easy.