Welding Tips and Tricks

I have quite a bit of stainless steel that was salvaged from commercial counters, not food service counters just reception type counters. my questions are:

is there a reliable way to determine the type.

if not what filler is a good work around.

is there a pretty safe assumption when dealing with stainless found on commercial counters and cabinets.

thanks guys and gals.

creek.

Granddaddy wrote:I have quite a bit of stainless steel that was salvaged from commercial counters, not food service counters just reception type counters. my questions are:

is there a reliable way to determine the type.

if not what filler is a good work around.

is there a pretty safe assumption when dealing with stainless found on commercial counters and cabinets.

thanks guys and gals.

creek.

Check it with a magnet. The 400 series is magnetic. The 300 series is not, except for 312. Or you can do a spark test. Ferritic(400 series) will throw sparks, the 300 series(austenitic) throws less. You can find a spark chart on-line. A good all around filler for unknown alloys is 309 or 312 AKA Supermissileweld. If your metal isn't magnetic then it's a good bet that it's probably 304.

thanks XNP, i'll give it the magnet test.

creek

Depending on what you are planning to do with it, 308 should work fine as well, just depends on the service your going to put it in after you are done with it.

thanks Mr. O,
I don't have any thing definite in mind, I have never welded stainless so I will probably start by cutting some coupons from the aprox- 3/8'ths X 1.25 corner trim pieces and trying my hand with three processes, mig, stick and tig and see how it progresses. I like giving my grandkids things I made in hopes it will mean as much to them as things my grandfathers made or owned mean to me so I am thinking tool boxes and storage boxes for their camping gear. Christmas before last I made the boys knives and sheaths and the girl a purse complete with tinkerbell buttons, my wife and daughter were quite shocked by the purse but I couldn't leave the little gal out and that's what I came up with. I also built them a little 8 foot hybrid ( forgive the spelling ) peero / john boat and man was that a hit even though you could tell it was my first boat build. oh' the first knives to.

thanks again.

creek

Aren't most kitchen tables and counters 316?

Poland308 wrote:Aren't most kitchen tables and counters 316?

I have always heard that common SS items are usually 304. I know 316 has better corrosion resistance than 304 so it's more expensive.

I've only welded on a few counters/ sinks for commercial kitchens. Those all had manufacturers name plates. I just googled them to find out the material specs.

316 is common for marine applications and supposed to be used within 5 miles of an ocean coast. 304 is about the cheapest so you can see why manufacturers would favor it. I wonder what stainless appliances are made of...betting 400 series.

304 is the standard kitchen grade.

The main difference between 304 and 316 is 316 has molybdenum added to it which gives it an acid resistance and so allows it to stand up to more nasty stuff.

If you'r looking to do cool little gifts like that, stainless countertops should be just fine, most likely they are 304, rarely will they be 316. You probably just want the corrosion resistance malleability of stainless for your ideas which it should offer.

Stainless welding is fairly easy, just be careful with cooking it, once stainless gets hot and molten, it tends to float some materials around which can prevent the oxide layer from building on the surface of stainless. This happens due to the chrome in it. Once metal has more than 18% chrome (Or something similar) it is considered to be "stainless" as the chrome will protect it.

I could go on for hours, I am trying to stay on track.

BUT! Most importantly, make sure you leave the torch with its postflow over the weld once your weld is done, give it a good 5-10 second post flow to allow the weld to cool with a shield over it and then your good to go, by removing it too fast you can contaminate it and once again, prevent the oxide layer from rebuilding.

By the way, that oxide layer rebuilds naturally once the chrome surface is in contact with oxygen that's why there is such a stress on not contaminating stainless, dedicated brushes, grinding wheels, etc.

Sounds like a great idea though, I think they will be happy. Are you planning on painting any of this stuff? Stainless is very good at getting discoloured after welding which ruins the aesthetics but there are ways to handle it, just depends how far you want to go.

There, I feel better now that I got to babble

exnailpounder wrote:316 is common for marine applications and supposed to be used within 5 miles of an ocean coast. 304 is about the cheapest so you can see why manufacturers would favor it. I wonder what stainless appliances are made of...betting 400 series.

Higher quality stainless appliances are 304 from what I see, most of them aren't magnetic.

You owe me a beer too.

Olivero wrote:304 is the standard kitchen grade.

The main difference between 304 and 316 is 316 has molybdenum added to it which gives it an acid resistance and so allows it to stand up to more nasty stuff.

If you'r looking to do cool little gifts like that, stainless countertops should be just fine, most likely they are 304, rarely will they be 316. You probably just want the corrosion resistance malleability of stainless for your ideas which it should offer.

Stainless welding is fairly easy, just be careful with cooking it, once stainless gets hot and molten, it tends to float some materials around which can prevent the oxide layer from building on the surface of stainless. This happens due to the chrome in it. Once metal has more than 18% chrome (Or something similar) it is considered to be "stainless" as the chrome will protect it.

I could go on for hours, I am trying to stay on track.

BUT! Most importantly, make sure you leave the torch with its postflow over the weld once your weld is done, give it a good 5-10 second post flow to allow the weld to cool with a shield over it and then your good to go, by removing it too fast you can contaminate it and once again, prevent the oxide layer from rebuilding.

By the way, that oxide layer rebuilds naturally once the chrome surface is in contact with oxygen that's why there is such a stress on not contaminating stainless, dedicated brushes, grinding wheels, etc.

Sounds like a great idea though, I think they will be happy. Are you planning on painting any of this stuff? Stainless is very good at getting discoloured after welding which ruins the aesthetics but there are ways to handle it, just depends how far you want to go.

There, I feel better now that I got to babble

You were babbling? Sounded good to me...I just think maybe you need some trim...that'll shut you up for awhile

316 filler is cheaper than 309 or 312 fillers and will weld any combination of commercial 300 and 400 grades that you are looking to do.

Im pulling my foreigner card, what's a trim?

Olivero wrote:Im pulling my foreigner card, what's a trim?

Google it. I bet all the old timers know what trim is...or used to be Or look up poontang...same thing

exnailpounder wrote:

Olivero wrote:Im pulling my foreigner card, what's a trim?

Google it. I bet all the old timers know what trim is...or used to be Or look up poontang...same thing

Lol. Had to look for Trim in slang dictionary

Doesen't keep me quiet for long

Sometimes to trim something you just( tear a piece off.)

Olivero wrote:

exnailpounder wrote:

Olivero wrote:Im pulling my foreigner card, what's a trim?

Google it. I bet all the old timers know what trim is...or used to be Or look up poontang...same thing

Lol. Had to look for Trim in slang dictionary

Doesen't keep me quiet for long

Me neither...when I get some I whine to get more...probably embarrassing but I don't notice

Hahaha.

now that we settled that

Do you know if you have to repassivate stainless after any welding regardless? From what i know you can loose the corrosion resistance if its cooked too much but I believe that if you don't overcook you can get away with just cleaning it up?

Got any info on that one? Always wanted to know if I should feel bad for leaving a stainless weld un-passivated.

Olivero wrote:Hahaha.

now that we settled that

Do you know if you have to repassivate stainless after any welding regardless? From what i know you can loose the corrosion resistance if its cooked too much but I believe that if you don't overcook you can get away with just cleaning it up?

Got any info on that one? Always wanted to know if I should feel bad for leaving a stainless weld un-passivated.

I repassivate on sanitary welds. Rub In some Barkeepers Friend, takes the colors out and makes the welds look like natural stainless...allows the oxide layer to reform. Highly recommended. For non-sanitary...let your conscience be your guide.

Olivero wrote:Hahaha.

now that we settled that

Do you know if you have to repassivate stainless after any welding regardless? From what i know you can loose the corrosion resistance if its cooked too much but I believe that if you don't overcook you can get away with just cleaning it up?

Got any info on that one? Always wanted to know if I should feel bad for leaving a stainless weld un-passivated.

If you cook it, it's beyond passivation as you've boiled the chromium out. The color you see is contamination from atmosphere, and passivation, whether with paste or with a machine, removes the contamination. @rick_h will have a better answer as to why you passivate in the food service industry.

Sent from my VS995 using Tapatalk

Olivero wrote: Do you know if you have to repassivate stainless after any welding regardless? From what i know you can loose the corrosion resistance if its cooked too much but I believe that if you don't overcook you can get away with just cleaning it up?
Got any info on that one? Always wanted to know if I should feel bad for leaving a stainless weld un-passivated.

As you know the 300 series stainless is used in many applications, most of which aren't passivated. If good welding procedures are used the haz can be controlled and passivation isn't required. In sanitary applications it can be required as well as piping for the water and chemical industry. It really depends on the use (the environment) the part will operate in.

At my last job we welded 316L, duplex and other stainless piping which all had to be passivated (electropolished) per the customers requirements.

Olivero...here is a great article on passivation. http://www.thefabricator.com/article/tu ... -stainless
I have quenched stainless with wet rags to draw out heat when welding thick to thin to hold down warpage and my well water has tons of iron in it and it will turn a stainless weld black. That's not good. You need a process to remove that iron and let the metal reform an oxide layer. Oxalic acid is one way but is more of a pickle.

exnailpounder wrote: I have quenched stainless with wet rags to draw out heat when welding thick to thin to hold down warpage and my well water has tons of iron in it and it will turn a stainless weld black. That's not good.

You might consider investing in 5 gallons of Distilled Water from the store and keeping it handy as a quench bucket in lieu of using your well water. Cheaper than acid and saves you from contamination of all your welded metals.

cj737 wrote:

exnailpounder wrote: I have quenched stainless with wet rags to draw out heat when welding thick to thin to hold down warpage and my well water has tons of iron in it and it will turn a stainless weld black. That's not good.

You might consider investing in 5 gallons of Distilled Water from the store and keeping it handy as a quench bucket in lieu of using your well water. Cheaper than acid and saves you from contamination of all your welded metals.

I do alot of welding for homebrewers on their kegs. Sometimes they bring over brand new kegs and when I weld on them I will try to keep warpage and distortion down as much as possible by drawing out heat with a damp rag. On an old beater keg, not so much. I actually have used distilled water but I don't even do it that way anymore. In reality, all stainless should be repassivated all the time, every time, but who can afford to do that? My way is more of a pickle and wouldn't be acceptable in true food service but it's better than nothing for a brewer. I learned of Oxalic acid from a friend of mine that welds for brewers too.