I'm making a table out of 1.25" x 0.25" cold-rolled steel. I welded the base and top and they turned out great. For the four horizontal posts that join the base and top, I decided I want to try to braze them. The reason is the joints will be highly visible and I don't want to burn into the steel. And with the bronze, I can file/sand it down really tight so it looks good, and I don't need the strength.
So my question is: What settings and consumables do I want to use to do this?
- Amperage
- Tungsten type and size
- Brazing rod size
Any other hints on brazing would be greatly appreciated also.
Since you have ¼" steel to braze, I'd say no less than 150A to get a good red-hot spot going quickly. One common mistake is new TIG welders for some odd reason set the amps super duper low for the thickness they are working with. I've seen posts where someone was trying to weld ¼" steel with 120A and was wondering what he was doing wrong. You can set the amps as high as you want, you just have to properly modulate it with the pedal. You must to use the pedal to modulate the heat, so don't get hung up too much on settings, as long as you are in the ball-park. The goal is that the rod should melt & puddle when touched to the steel just outside the arc, from the sheer heat, but without creating an initial excessive [steel] puddle. For this you need a small-diameter SilBr rod, I'd say 1/16" diameter. Don't be fooled by the "Silicon bronze melts at a lower temp than steel" line. Temperature is but one small manifestation of heat-conduction and thermal capacity. It still requires lot of heat to melt, is what a lot of people don't realize. As always, don't practice on the part. Make a mock-up joint. Fine tune your settings there. Most any tungsten except for pure will work. 3/32" will be all you need.
Set your pedal amperage to about 10-20% lower than what you would need for steel. This is still a little high but doesn’t hurt to have some extra when you need it. Light up on the base metal and quickly form just the tiniest pin prick of a puddle. Then back it off a hair to where the puddle solidifies again. This is a great way to find the pedal position for when you can easily flow the brazing rod without melting the base metal. As you add the filler, you may need to increase amperage just a bit as it will cool the weld area.
ERCuSi-A Silicon Bronze is a good choice for filler. Practice quite a bit before you attempt to braze the actual parts. It takes a bit to get a feel for the flow of things when TIG brazing. 1/16” and 3/32” rods will probably cover your needs based on the exact joint configs you are doing. Make sure everything is nice and clean.
ERCuSi-A Silicon Bronze is a good choice for filler. Practice quite a bit before you attempt to braze the actual parts. It takes a bit to get a feel for the flow of things when TIG brazing. 1/16” and 3/32” rods will probably cover your needs based on the exact joint configs you are doing. Make sure everything is nice and clean.
I'd second lower amps than what traditional TIG welding would require. But I would differ on the filler size and encourage 3/32 at a minimum, really I'd use 1/8" especially given your intention to grind the weld down afterwards.
Your base metals need to be super clean, even your filler too. A #8 or larger cup, closer to 20CFH is my practice. I also like pulse in these situations because if you blast the puddle then dip, you can get a very nice stack by controlling the heat input.
You do NOT want enough heat to make the parental metals wet; just hot enough to make the filler flow.
Your base metals need to be super clean, even your filler too. A #8 or larger cup, closer to 20CFH is my practice. I also like pulse in these situations because if you blast the puddle then dip, you can get a very nice stack by controlling the heat input.
You do NOT want enough heat to make the parental metals wet; just hot enough to make the filler flow.
Don't hold me to this, but I want to say it was Wyatt Swaim who said in one of his videos on silicon bronze, to set the amperage very low. It doesn't work for me at all, but he seems to think that's the ticket. At least that's what I recall...Oscar wrote:Since you have ¼" steel to braze, I'd say no less than 150A to get a good red-hot spot going quickly. One common mistake is new TIG welders for some odd reason set the amps super duper low for the thickness they are working with. I've seen posts where someone was trying to weld ¼" steel with 120A and was wondering what he was doing wrong. You can set the amps as high as you want, you just have to properly modulate it with the pedal. You must to use the pedal to modulate the heat, so don't get hung up too much on settings, as long as you are in the ball-park. The goal is that the rod should melt & puddle when touched to the steel just outside the arc, from the sheer heat, but without creating an initial excessive [steel] puddle. For this you need a small-diameter SilBr rod, I'd say 1/16" diameter. Don't be fooled by the "Silicon bronze melts at a lower temp than steel" line. Temperature is but one small manifestation of heat-conduction and thermal capacity. It still requires lot of heat to melt, is what a lot of people don't realize. As always, don't practice on the part. Make a mock-up joint. Fine tune your settings there. Most any tungsten except for pure will work. 3/32" will be all you need.
kiwi2wheels
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Try using the machine on AC. The HF cleans the metal ( like the flux when O/A brazing ) and its easier to heat the base metal without melting. Clean material in weld area with red scotchbrite discs.
Update: I spent some time brazing today. Really glad I did, and the tips here are excellent. I got to the point where I could lay a really nice bead on a plate, or a butt joint. Inside corner joints were harder for me and they turned out passable but not great on the table I'm working on. Generally I was working in the 80-100 amp range with both 3/32 and 1/16 filler.
Question: what would you use to grind down brazed joints the nicest and smoothest way possible on inside corners, while minimizing impact to the steel?
Question: what would you use to grind down brazed joints the nicest and smoothest way possible on inside corners, while minimizing impact to the steel?
Here's a little known internet gem for ya. This is a mom-n-pop hardware store that added on a website and holy smokes do they have a great variety of things for sale. Country of origin is about 80% USA and if you go through the sections, they've got tools you've not seen in decades.
Here's some round files for example.
https://www.harryepstein.com/catalogsea ... round+file
Here's some round files for example.
https://www.harryepstein.com/catalogsea ... round+file
eelman308 wrote:^^^^^. Got my LaSquare thru them. Good people to deal with
Glad to see someone else shops there. I love dealing with them. Milton air fittings and quick couplers, I buy em by the box full for at work. A few years back I bought enough to replace every coupler in the building and throw the old stuff away. One of the best moves I've made and I didn't have $150 in it. I enjoy just shopping through all the stuff online and placing an occasional order for stuff for the tool box. It's like a candy store for guys who appreciate hand tools.
I also enjoy the touch of "Box Art" and I get it EVERY time. I wouldn't care if they charged for it I'd still do it. I think they have kids/grandkids to watercolors on the boxes and it's really cool what they do. I keep the boxes and make sure to reuse them when I ship things or store stuff in em.
Seems like a great shop, and that box art is really cool. That alone makes me want to buy from a shop like that.
I do wonder if the name has hurt their sales at all over the past year or so. I reeled back for a second when I saw it. Little things like that can sometimes have an impact, unfortunately. Similar thing several years ago with the plethora of companies that had ISIS in their names or brands which was more common than you may think. A buddy of mine saw some impact from that and ended up removing that name.
I do wonder if the name has hurt their sales at all over the past year or so. I reeled back for a second when I saw it. Little things like that can sometimes have an impact, unfortunately. Similar thing several years ago with the plethora of companies that had ISIS in their names or brands which was more common than you may think. A buddy of mine saw some impact from that and ended up removing that name.
I never even considered that, so I can't imagine there's a widespread connection made, but ya never know I guess. Since it's the owners name, I doubt anything is gonna change.Spartan wrote:Seems like a great shop, and that box art is really cool. That alone makes me want to buy from a shop like that.
I do wonder if the name has hurt their sales at all over the past year or so. I reeled back for a second when I saw it. Little things like that can sometimes have an impact, unfortunately. Similar thing several years ago with the plethora of companies that had ISIS in their names or brands which was more common than you may think. A buddy of mine saw some impact from that and ended up removing that name.
It's not that people would necessarily confuse the two, but it creates an instant negative connotation with the brand/store for many consumers, and can hurt sales. I'm not guessing on that...it's a well researched thing, and as mentioned above, corona and isis are just two recent examples of many.cj737 wrote:Are you referencing Harvey Epstein? Who would confuse the two?Spartan wrote: I do wonder if the name has hurt their sales at all over the past year or so.
But I do hope that everyone knows that I am no way trying to insult him or his brand, and I will likely buy from him at some point in the near future. I really do like how he does business. My initial comment was more just me thinking out loud, and was probably inappropriate for the scope of this thread for me to make such a comment.
Not inappropriate at all, just thinking out loud and we all get it. I just know that I personally don't make connections due to a last name and likely they don't want customers who would make such a reach. I've known some pretty good people with the last name of Manson as well. 
