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System 48 Flux vs. Stainless Light

Recently, a few folks have been asking what the difference is between our Stainless Light Flux and System 48 Flux. Both are paste fluxes for silver brazing. Stainless Light was originally designed for the then new stainless steels like Columbus Metax, XCR and Reynolds 953. Fred Parr had a silver fillet brazing filler, but there were no existing flux that worked to allow this amazing alloy to flow well on stainless steels. Stainless Light took close to a decade to develop, and went through several formula changes to arrive at the current flux. Stainless Light is great on non-stainless steels too! It has been the primary silver flux in my shop for years. It has a great temperature range, you can even braze LFB if you work quickly!(Not a recommended use!) It has a great shelf life and low toxicity. What makes this flux different is its ability to make the filler flow quickly and at the lowest temperature. It is also particularly aggressive at removing chromium oxides and opening up the grain structure of the base metal. Stainless Light’s activity really starts kicking in at about 400 degrees. At that point chemical changes start to take place within the flux. Proprietary compounds that have been inert up until now are acted upon by the flux itself. These compounds are transformed into highly active deoxidizers, and pre-flow agents. This happens in several steps, and you can actually watch it happen as you heat the flux. It doesn’t just melt, it changes. Watch the color changes, there are five! (If you don’t hear from me again it’s because Freddy killed me for revealing too much!)

Well, if it’s so darned good, why do you need another flux? Well, for the same reason I “need” so many bikes. Specificity. Each flux has its own specialty. Stainless Light is unbeatable on stainless.

The “System 48″ silver brazing filler was my idea, the Flux was Freddy’s. I wanted a filler that was stronger than 56, flows as well, fills larger gaps, contains no cadmium, and works at a low temperature, and has improved eutectic characteristics over 56. The wire mill said “Sure, we can make that” but you’ve got to order a zillion pounds… Well, I was chatting with another mill and told them what we wanted. She said, I’ll call you back? A few hours later, she called back and said “we have that in stock”! A large aerospace contractor ordered a run and there was some left, so we bought it!

Freddy was excited and said we needed a new flux to go with it. Dave Bohm and I said why? Freddy sagely explained how stainless light was too fast for many braziers, its texture while good was not great, and its cleaning abilities were tailored toward oxide removal, and not traditional cleaning. System 48 flux has the best texture of any flux I’ve ever worked with. It goes on, stays put, and doesn’t drip. It has a pure white color. I can hear people saying “It’s the same as Ha****”, well try both, see which burns first, and take a whiff of each! Don’t judge a flux by its color! We can make any of our fluxes whatever color you’d like! You like White? Pink? Green? Black?, but there’s no point – it’s just color! System 48 flux contains no potassium bifloride- you know that stinky stuff that you taste for 12 hours if you braze with poor ventilation! It’s also bad for you. In action, System 48 removes rust, oil, and mill scale very aggressively. It flows the rod quickly, but not too quickly. It’s great on 4130 and all of the non-stainless tube offerings from every manufacturer today. It is also great with 56. It slows the flow down just a bit, and keeps things a bit more controllable. One builder recently described how System 48 would flow without requiring capillary action. It just follows the heat, flows where you want, and builds up if you want it to.

Email me if you want to try some, or have questions

Have a great week,


What’s a System? Isn’t Flux all the same?

One of the most important things Cycle Design is doing is to make products that work together. When you use a generic brazing filler rod and generic flux, the products are not designed to work together. They are probably made by different manufacturers, and certainly don’t take bicycle construction into account. At Cycle Design, our products are specifically designed to work together. System 48 is a product and a concept. The filler rod is designed to be stronger than the 56 and to fill gaps better. It also has excellent flow characteristics and is easier to work with. I’m sure the first thing people will ask is “Does it work with Stainless Steel Light (SSL) Flux or other flux’s?”. Well Yes, but let’s explore the issue. Stainless Steel has different types of surface oxides than other steels. That’s why it doesn’t rust. SSL is designed for stainless, and it’s deoxidation characteristics are also designed for stainless. System 48 Flux is specifically designed for the lower chromium steels that we typically use. System 48 does work with stainless, just not as well as SSL, and System 48 is superior on dirty mill scale covered steel. Look at the inside of your tubes- System 48 flux will remove these oxides. It is more active, because it should be. Silver doesn’t flow as easily on Stainless, so SSL has more and different flow agents. System 48 has a different balance of flow agents better suited to more traditional tubesets.

I’m sure many builders are thinking; “My frames don’t break, so I don’t need to change from what I’ve been doing all these years.” Well that is true, however certain parts of the frame are more prone to failure. On a traditional lugged frame, brazed with 56, there are a few weak points. The brake bridge, Seatstay to Seat Lug joint, and chain stay bridge are areas where the braze is less strong than ideal. System 48 is excellent for these areas. Even if you want to keep with 56 for your lugs, at least try System 48 on your bridges and seat stays. There is no downside, just stronger joints. Give System 48 a try, I think it will become a valuable part of your framebuilding arsenal.

Have a Great Week,

Wade Barocsi

Welcome to the Cycle Design Blog

The Cycle Design Group concept was formed by Fred Parr in 2003. “Freddy” as he is known, has always been available as a resource to ask questions to. He has probably helped more frame builders get started than any modern frame builder. Freddy’s vision was of a group of like-minded frame builders who share information, develop and share new techniques and further frame building technology. He also envisioned a buying group. Most large welding product companies do not serve frame builders well. They are unfamiliar with our needs, and require volumes far beyond the means of any frame builder. They also (and this is almost unbelievable) have little knowledge of how to use their products. They are just product numbers! The customer is supposed to have their own engineering staff to consult. To add further insult to injury, the minimum quantities just to get in the door are huge. Builders typically buy flux in 1-5 lb quantities. They want you to buy hundreds of pounds. So No tech support, no familiarity with our needs, poor product selection, and outlandish prices. These are some of the problems that have resulted in the founding of Cycle Design.

Freddy has been my friend and mentor for many years. He’s always been available to answer questions, give tips and pointers. Freddy has always enlisted the help of group members. He feels that everyone can contribute. Each of us has different skills, and techniques. As Cycle Design began testing and developing products, it was the Cycle Design members who tested and approved each. For example one of Freddy’s early flux’s was “Safe-T-6″ this excellent flux is far safer than what was available commercially. It eliminated many of the toxic compounds in other flux’s. Safety six worked great for Freddy, but he is a master brazer. Some of the newbies found it burnt too easily. So he reformulated, a new version that was much more heat-resistant. Next he worked improving the formula to improve its ability to de-oxidize, and clean the steel. Finally some of the developments from the Titanium Brazing Project resulted in further (and revolutionary) advancements to the brazing of stainless steel and aluminum. There were at least four versions that followed, each resulting from group feedback, and providing incremental improvements. The most current version of this flux is Stainless Steel Light (SSL). This flux has been revolutionary. It is the single most advanced flux that I have ever worked with.

I will expand on our product development at a later time, or give Freddy a call, and he’ll tell you all about it.

Cycle Design had been growing over the years, and eventually it became too much for one person to handle. A few years ago, Dave Bohm (Bohemian Bikes) and I stepped up to help with the load. Freddy is still heavily involved with Cycle Design, but he is tired of packing and shipping. He lives in Douglas AZ not exactly a centralized shipping hub. Cycle Design now has two US shipping points; Cheshire, CT (Wade) and Tucson AZ(Dave). We have been steadily increasing our purchasing volumes, which have been resulting in progressively lower prices for all. We have also been re-investing ALL Cycle Design funds in to new product development, and group benefits. I would expect this to continue, as we have quite a few new products in various stages of development.

If you’ve been reading this far, thank you!

We will continue to develop the Cycle Design products, and the Cycle Design Group. There is a lot to do, and Freddy, Dave and I would be happy to have further help. This is an open project. If you’d like to help, let us know. Are you good with websites? Graphic arts? Metallurgy? Are you a total beginner? Beginners have contributed significantly in product testing and development.

Welcome aboard, and thank you all for your support.

Wade Barocsi,
Cycle Design Director