BRAZING: alloys & fluxes.

[Eric Estlund]

gasfluxers are a crutch that most domestic framebuilders learn to walk with atmo.
it's use has no effect on how much paste flux is needed.

Not entirely true. In a past life I've build loads of bikes with no additional paste flux- it all came through the hose. Gasfluxers come out of industry were there is a need to balance quality, volume, and clean up. Used properly they are great for brass or nickel brazing.

I currently use one for tacking, non bike stuff and as a redundant system for paste flux. I think of it as another tool, and treat it as such. I certainly don't consider it a crutch to hold up a sub par skill set or build method (nor do I see others using it that way?).

My bottom line- I absolutely do not need one, but like to have it for certain situations. I don't use as much paste flux as I see other guys use, but I don't lather on as much even when I'm not using the gas fluxer.

[WadePatton]

great replies guys, thanks.

less char eh? noted.

yes, methinks i recall someone mentioning no-paste atall for tacking and small braze-ons. makes great sense.

slathering--yup, i've met the type. "king of the flux" i dubbed him. (it was a tx thing.)

[Dave Porter]

A mig weld cools down very rapidly, and the shrinkage sets up a lot of stress. Put the stresses generated by riding on top of that and you've got a road to failure

Hi Marten,
You know in this case of the DT exploding, I think it was only coincidental. The seat tube is the one I tacked! Then I run the fillet around the seat tube leaving the DT mitered butt bare. Then the DT is literally laid into the frame with out support and the fillet is then completed, so I think this was something else altogether. Perhaps a tube defect? BTW, Columbus lists TIG and MIG as suitable for use with Spirit, They in fact tout the products resistance to overheating, but your observation of rapid cool down of a tack versus a continuous weld is valid. Thanks for the input, as always.
dp

[Freddy]

Hate to start a war over inline fluxers but the effect on bond over using the correct elemental flux does vary a lot.

There are current liquid fluxes that have been formulated to keep up with advanced filler alloys but are not made by Gasflux or Jetflux that work to inspection requirements in SS brazing.
Gasflux on bronze or nickel bronze for steels is very common and provides a fine bond for more generic brazing operations.
When used in newer tech operations with silvers and very much on SS joining it retards the bond integrity, the only compatable liquid is Torch Flux, several versions and temp ranges.
Another case of new tech being used but not much of this trickles down to small shops and is more expensive with high qty min purchase required.

I can validate that using one(GF) to join steel with 680 is just fine - that is what it was made for many years ago.
Almost all the paste fluxes for silver are now adding new formulas that contain flouride agents that are not 100% compatable.
What happens then is the inline flux retards them so action change by seeing a good flow out but once agian the bond is reduced compared to using the paste alone (silver).
Each case of alloy parent and alloy filler has a fluxing action dependency for best possible results.
As bonding issues become more critical with the very thin tube offerings this is a topic that will become very important.
I recieved a reply from engineering data request I made last week, management feels this market is too small to release any unapproved information other than is printed on public tech sheets?
So you won't see me post beyond that here.
You guys are doing a fine job of sorting things out. (Which is good since it already has been and gets updated where the goods come from)
It is a shame that publications are so full of past issues that where wrong then and have been revised for decades but still in print, makes it hard to stay unless topic strings like this are objective in practice and current supply.
For example I could go on for pages about practices in 1970-80 and quite a few more resulting from 2000-2010 regarding SS.
Whole new concept, it is improved well beyond expectations and text book? Success derived from current issues and data and beta only .
Fact is if any of you rode back in time with the pipe and parts we have today, most liikely you would meet with a non-receptive hostile opposition.
Times are changing fast and new joining patents around the world are showing up at alarming speed, I call it a turning point?
The generic low ball vendors are getting on the outsource wagon, the industry heros are working in overtime to compete with industry requirements where quality is first or fail.
You choose?

[e-RICHIE]

the only compatable liquid is Torch Flux,

what is this atmo?

[dbohemian]

what is this atmo?

Its a brand name of a flux meant to be used in gas fluxers. It has some real positive feedback so far and it may not be anytime real soon but I plan to offer it for sale as buying it in individual quantities isn't really financially viable. Keep your eyes and ears open

[David Cheakas]

What size rod are you guys using? I recently built four or five frames with 1/8" rod from Hank and I had a little trouble with consistent heat control.

[e-RICHIE]

What size rod are you guys using? I recently built four or five frames with 1/8" rod from Hank and I had a little trouble with consistent heat control.

always use 1/16" here atmo.

[conorb]

always use 1/16" here atmo.

+1 on that.

Conor

[Freddy]

1/16 makes for an easy fillet, the hand motion does the rest.

[David Cheakas]

I normally do use a 1/16" rod, but I thought Hank told me that he was selling the 1/8" rod to many builders and they preferred that to the 1/16". I though I'd give it a try, but I've already gone back to the 1/16".

[EricKeller]

I really like 1/8 rod.

widget.jpg

[Freddy]

Eric,
We will have 3/32 in the new LFB, right now there may be 1/8 at P&I mill.
I will check on monday and post back.
We did put part of the website back at http://www.fredparr.com and we are still working on it.

1/8 is harder for me to flow inside, works great for build ups and of course we should have them all.
Takes time with new alloys to get stock made, stay tuned.

[CyclesNoir]

Let's take this a different direction for a moment.

I usually slather on lots of flux, clean everything and have extra available if I have to push it into the joint. As I get faster, there's not so much need to have extra flux to push around.

Freddy recently told me about brazing up a bike (maybe Wade B's daughters bike) with only a tablespoon of flux.

Anyhow, recently I received a new shipment of Stainless Light. It now has a slightly greyish color, as opposed to pure white. And it seems creamier than ever. Really easy to apply thinly with good coverage.

So after a couple of test joints, I tried brazing some chainstays to the BB using the flux only on the inside - except for what pushed out while assembling the joint.

Everything flowed beautifully. There's probably no advantage to this approach - there's more cleaning of metal afterwards. But it was fun to see things work.

[EricKeller]

thanks for reminding me that widget pictured in my previous post is still soaking.

I like stainless lite, but you have to get past the disconcerting moment where it all seems to have disappeared. I'm looking forward to the LFB.

[Curt Goodrich]

Next time you're ordering some brass flux from Gasflux try type B-4. It's a little different than type B. I like it better. It's not night and day better but it's better IMO.

[steve garro]

I usually slather on lots of flux, clean everything and have extra available if I have to push it into the joint. As I get faster, there's not so much need to have extra flux to push around.

brazing up a bike (maybe Wade B's daughters bike) with only a tablespoon of flux.

Odd that you should say that, i have a tablespoon to measure flux for brazing a whole frame! while we are at it I will add that i use two rods { with some left over for tacking} on the dropouts & five rods to braze the actual frame. - Garro.

[EricKeller]

Steve - you use 1/16 rod?

I am not sure if I really like the 1/8 rod or if it's just because I've never used the Gasflux rod before and it's better than what I was using.

[steve garro]

Steve - you use 1/16 rod?

yep. - Garro.

[Freddy]

About using a lot of flux?
I never did and I show students how to use very little.
This is why I made powder flux and paste version for our completely new formula of LFB
It is shipping out and we will get some realtime feedback soon.
Guys like Curt are getting a sample of the system so I am sure it will get a fair testing.
You all can thank the economy for this product, time and money dictated re-noodling
the venerable mid-range lfb, ours does not depend on lead content and that flow is done
with some metal oxides and of course more tin content.
Nothing as earth shattering as the Fillet Pro but well below flow temps of any other rod without
silver.
Brinnell is 94-95 and very ductile and easy to finish.
The fluxes are without flourides and easy to remove after joining with water only.
And very little gets the job done.
So after two years of study and one year of active R&D it is improved and in the sustainable
supply line.
For brother garro, it is a varient of the rod he likes and would not have become here and now without his
input.
Safer stronger faster and no flare from the flux....