# Soldering/Welding Techniques

#### cmartinez

Joined Jan 17, 2007
6,469
302 is an austenitic grade very similar to 304 (generically known as 18/8). Hopefully you have 302L (for low carbon) this allows for more heating and welding without creating chromium carbides which could have a negative effect on corrosion resistance. Doe this come into contact with water and that's why it was chosen? It's not a particularly hard material in case you need wear resistance as well.
Thanks, that's very valuable information. Yes, it does come into contact with water. As a matter of fact, it will be permanently submerged. But wear resistance is not an issue.

#### Wolframore

Joined Jan 21, 2019
1,282
If wear is not an issue brass is a good alternative for water contact, it's easy to solder and easy to drill and machine. Stainless can get tough to work with due to work hardening from the Nickel and some of the austenite formers.

#### cmartinez

Joined Jan 17, 2007
6,469
If wear is not an issue brass is a good alternative for water contact, it's easy to solder and easy to drill and machine. Stainless can get tough to work with due to work hardening from the Nickel and some of the austenite formers.
The problem I see with brass is rigidity, which is important for this application. I'm seriously considering tack equipment at this point. My current consideration is, do I need to use argon?

#### Wolframore

Joined Jan 21, 2019
1,282
C/M anything more than general suggestions and information requires more information. I have no idea what you need. Generally shielding from oxygen is recommended but you can use CO2 in some cases and it costs less but it won’t work well with a flame type heat. It also depends on the process and other variables.

#### cmartinez

Joined Jan 17, 2007
6,469
C/M anything more than general suggestions and information requires more information. I have no idea what you need. Generally shielding from oxygen is recommended but you can use CO2 in some cases and it costs less but it won’t work well with a flame type heat. It also depends on the process and other variables.
I don't know what more info to give you. A detailed drawing of one of the parts I'm trying to solder/weld can be found in post #88.

At this point I'm deciding whether to acquire a tack argon spot welding machine.

#### Wolframore

Joined Jan 21, 2019
1,282
Ohhh gotcha I played with something similar at the last Fabtech. Yeah Argon CO2 mix. The one I played with was a microscopic tig welder it pulses an arc. They let me weld little coupons and even razor blades together.

#### cmartinez

Joined Jan 17, 2007
6,469
Here's another bit of info I forgot to mention. I don't know if it's important. The ss 3/32" rod I want to weld to the ss part is a small segment cut from a soldering rod stripped off its coat of flux.

#### MrAl

Joined Jun 17, 2014
6,513
What have I gotten myself into???? ... I'm trying to solder a part cut from a 1/16" stainless sheet with a 3/32" stainless rod ... and so far I've only made an unspeakable mess ... I'm going to start looking into jewelry making techniques ... YouTube, here I go...

Hi,

Nice drawing BTW.

Couple things you can try...
1. Heat the metals not the joint until the joint becomes hot enough to melt the solder.
2. Wet (with solder not water) each surface to be soldered before assembly, then press and hold together and reheat close to the joint to meld the two surfaces and thus the two parts together.

Also, afterwards test for strength.

Once the two surfaces get

#### Wolframore

Joined Jan 21, 2019
1,282
is the soldering rod stainless? Do you have the info?

#### cmartinez

Joined Jan 17, 2007
6,469
is the soldering rod stainless? Do you have the info?
Yes, it is stainless. And no, I do not have the exact info.

#### cmartinez

Joined Jan 17, 2007
6,469
Hi,

Nice drawing BTW.

Couple things you can try...
1. Heat the metals not the joint until the joint becomes hot enough to melt the solder.
2. Wet (with solder not water) each surface to be soldered before assembly, then press and hold together and reheat close to the joint to meld the two surfaces and thus the two parts together.

Also, afterwards test for strength.

Once the two surfaces get
Thanks for your help, Al. Although I'm currently leaning on using argon tack welding for this particular purpose, I'll definitely still be using silver soldering in a different process.

That's why I've ordered a bottle of Superior #71 Flux for testing purposes. That should make a hell of a difference, from what I've seen in the promo videos.

#### Wolframore

Joined Jan 21, 2019
1,282
You know welding and brazing metal is interesting. After 10 years of MIG welding I’m still learning. In fact I did the best weld in my life the other weekend. The weld looks so good it’s almost TIG quality. Then I go to an inside corner and it looks like an amateur all over again. When I have critical welds I take it to a welder. I will figure it out but wow it’s not simple.

#### jpanhalt

Joined Jan 18, 2008
7,933
At this point I'm deciding whether to acquire a tack argon spot welding machine.
I would advise getting a full fledged TIG welder. Maybe twice as much as what you show, but it can do both tack and full TIG welds. You can braze with it too. Some even advertise spool guns, which implies MIG capability too. The only thing TIG is not really good at are lengthy welds (e.g., 16") with thin (e.g., 14 ga.) sheet steel. The welds are OK and look great, it is adjusting for the shrinkage that gets difficult with long (e.g., 10') sections. Stick or MIG is probably better at that, and my TIG welder (I think all) can do stick welding.

I bought my TIG welder (a Miller) in 1983 and have never regretted getting it. I'll soon pass the 40 year mark. You may not get the same years of service (I hope you do), but my point is, a quality TIG welder will last a long time. Lincoln is another good brand, but I am prejudiced as it is a local Cleveland company. Here is one version that looks really good for what you are doing: https://www.weldingsuppliesfromioc.com/lincoln-square-wave-tig-200-welder-k5126-1?gclid=EAIaIQobChMImK3ml_aj5AIVCIzICh1F4wWdEAQYAyABEgKUQ_D_BwE

Mine has a little more current capability, as I was doing structural steel at the time. I don't think you will need much higher current than that Lincoln model.

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#### shortbus

Joined Sep 30, 2009
6,988
At this point I'm deciding whether to acquire a tack argon spot welding machine.
Why? You did see the word spot weld in the name didn't you? Spot welds are for two sheets of steel in parallel. Unless you've changed the design of the joint don't think welds from that machine are going to be strong enough. But Will wait to be proven wrong, have been before.

The ss 3/32" rod I want to weld to the ss part is a small segment cut from a soldering rod stripped off its coat of flux.
Again why? Why not use Tig welding rod with no flux coating?

That's why I've ordered a bottle of Superior #71 Flux for testing purposes.
So your also changing from silver solder to lead solder? That flux is for soldering with soft solder to stainless, it is similar to an old Eutectic flux I used back in the day. Looks like they go by another name now Castolin Eutectic. https://www.castolin.com/product/157 You can usually tell a soft solder flux from a silver solder flux by it's make up. Liquid for soft and paste or powder for silver this is for the heat they become active at. Liquids boil away before the heat gets high enough, where as paste and powder go through a phase change into liquid as the become active.

#### shortbus

Joined Sep 30, 2009
6,988
302 is an austenitic grade very similar to 304 (generically known as 18/8).
And 304 will rust at the welded joint.

#### cmartinez

Joined Jan 17, 2007
6,469
Spot welds are for two sheets of steel in parallel.
Yes, but they can also solder parts that are square with one another, as long as the parts don't protrude so much that the electrode cannot reach the desired spot. I checked my component's geometry, and I can accommodate for that adjustment.

Again why? Why not use Tig welding rod with no flux coating?
Because that's what I had available at the moment. But yes, I will look into Tig welding rod, thank you for the suggestion.

No, I will not be using lead solder, but rather Tin-Silver solder. Remember that at this moment I'm still deciding what to use, where and when. That's why I plan to try different techniques until I find the best one for my application.

#### shortbus

Joined Sep 30, 2009
6,988
Yes, but they can also solder parts that are square with one another, as long as the parts don't protrude so much that the electrode cannot reach the desired spot. I checked my component's geometry, and I can accommodate for that adjustment.
Again don't want to be a downer to you but can't really see how one for ~$500 is going to do the same job of the ones costing ~$5000, like the Sunstone, Orion or PUK. Heres a good discussion on them from Sunstone, with the micro arc about half way down the page. https://sunstonewelders.com/the-science-of-micro-welding/

And if you are thinking there won't be as much of a learning curve, compared to silver soldering, I hope your correct.

#### cmartinez

Joined Jan 17, 2007
6,469
Again don't want to be a downer to you but can't really see how one for ~$500 is going to do the same job of the ones costing ~$5000, like the Sunstone, Orion or PUK. Heres a good discussion on them from Sunstone, with the micro arc about half way down the page. https://sunstonewelders.com/the-science-of-micro-welding/

And if you are thinking there won't be as much of a learning curve, compared to silver soldering, I hope your correct.
Wow, that's a long article! ... but it looks very informative. I'll give it a thorough read. Thanks!

As for the \$5,000.00 dll machines ... I think I'll first spend 10% of that testing and learning things before I jump on the wagon ...

#### shortbus

Joined Sep 30, 2009
6,988
I just don't think if your going to depend on those micro welds to hold your pin in place that it will work, be strong enough. Those welders are mainly for jewelry not for something mechanical. For strength in a 90 degree joint situation like your doing, you need a fillet of some sort. And to get a fillet you need to add material to the joint.

I forgot all about this stuff before, but thought of it overnight. https://www.riogrande.com/Product/SilverPasteSolderSyringe560ExtraEasy/103101 Using it you would apply to the joint and fixture the parts in position and heat. It's a well respected way of doing jewelry work.