From the Argonaut Cycle blog.

"On to the new dropouts; my intention in redesigning my dropouts was to come up with a way to braze the dropouts to the frame with brass while still being able to keep the axle slot bare.  My current stainless drops allow this, but as you might have read in some of my previous posts, they create some unique challenges when it comes to brazing them into the frame.  Stainless steel can only be brazed with silver, and from my experience and from talking to other builders, slotting the stays and brazing the dropouts with silver just isn’t strong enough.  To unsure the viability of that joint I machine plugs that go inside the stays and braze to the interior and exterior faces of the dropouts.  This is a bulletproof solution, but it’s fairly cumbersome and adds a lot of steps to my build process.  Plus, polishing the dropouts after they’ve been brazed into the frame is a fairly arduous process.  The plugs also add unnecessary weight to the frame.

I haven’t abandoned my old dropouts at all.  They work really well and provide a very clean, more classically styled bicycle. I think they’re beautiful, but from a functionality standpoint, they don’t add much.  I decided that a two part dropout was really the way to go, as this would allow me to braze a steel connector piece to the frame with a nice brass fillet, and allow the removal of the dropout altogether during painting.  No more inconsistent masking details or scratches in the polish, and a removable dropout would also save the painter the hassle of masking off the dropout, thus saving me money.  Additionally, a two part dropout yields the ability to have an interchangeable single speed dropout!  I probably would have gone with a two part design regardless, but being able to swap out a geared dropout with a single speed dropout is a huge bonus.

On top of that, a two part design allows the use of materials beyond steel.  This first batch was done in 6/4 Titanium.  They’re stiffer than my old dropouts and 55 grams lighter per pair!  I’m so excited about this new design because it is far superior to any other dropout available, and on so many different levels.  They’re faster and easier to build a frame with, they’re lighter, they’re stiffer, they don’t have to be masked off during paint saving time and cost, and they’re interchangeable with single speed dropouts!  I feel a little like the Shamwow guy right now."

Argonaut Cycles