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Frame Forum: How to cut a design out of blank lugs
Cutting Blank Lugs
The sales pitch: I am starting a subject thread on how to cut designs out of blank lugs. Many of my framebuilding class students have some kind of artistic background and want to find another way to express their creative talents. Carved lugs – whether the design is very simple or complex - can add beauty, personally and individuality to a custom steel frame. Using the same lugs as everyone else can be boring. The same principles I’ll explain here also apply for making a head badge or modifying any lug.
Their history: There were a number of classic British and other European framebuilders that used some kind of cut-from-blank lugs in the past. The most famous is Hetchins. Information about its history, models and lug cutters can be found here: <www.hetchins.org> Often the British advertised their advantage as a stress-relieving feature that better distributed the load to prevent breakage. I suppose this provided a rational cover to buy something elaborate. European lug companies offered a variety of models with more complicated patterns. Probably the most famous example is the Nervex “Pro” lugs used on Chicago built Schwinn Paramounts.
Sourcing supplies: The supply of blank lugs has always been sparse. The old European lug making companies like Nervex (that long ago closed) had them available on special order but few have survived to this day. The Haden lug company in England was the last supply house to make them but they too went out of business 10 or 15 years ago. Sometimes a blank set turns up on eBay for about $100. My small supply came from Ellis-Briggs in West Yorkshire England where I apprenticed in 1975. They used to have an “International” frame model with cutout lugs that was popular in the 50’s. Jack Briggs gave me the rest of their old stock. Some of my students have made some really beautiful frames from these lugs.
Alternate methods: Today, builders that want lug decorations usually do a “bilaminate” construction. This is when 2 slip tubes are cut out and then brazed onto the main tubes and then fillet brazed together. There are several ways to do this to make these sleeves look or be like a lug. Claud Butler frames in England were made this way when lug supplies were scarce after the 2nd world war. While this is a good method, it is typically a bit beyond the skills of a beginner. It is easier and more practical to start with a blank lug.
A new source: Just by chance I saw the Nikko company from Japan at an industrial trade show in Chicago 3 years ago promoting their bulge forming process. Back in the 70’s they made lugs for early Trek bicycles. This method is different (and much nicer) than the stamped and welded way old European companies used to make lugs. There are no lumpy seams that need to be filed away. I talked to their vice president who said they still had the tooling to make lugs although it hadn’t done it in years. I convinced him to make some blank ones. It helped that I had taught in Japan in between getting my teaching degrees and remembered some Japanese. It has taken some time, but with Kirk Pacenti’s help, I now have a bunch of Nikko blank lugs in standard and oversize diameters as well as the more typical pointed shaped sets in my shop. These are for sale. Write me for details.
My interest in cutting out lugs: I became interested in cut out lugs when I bought a Hetchins frame in London during a bike tour of England when I was in college. Adding beauty to function really appealed to me and was the foundation motive in my desire to make custom bicycle frames. Over the years I’ve developed and refined methods of how to design and cut out blank lugs. I’ll share those methods with you here.
Index of future posts: I’ll have separate postings on: 1) pictures of some historical examples, 3) an outline step by step of how to cut out a blank lug, 4) a list of the tools needed, 5) how to create a design, 6) how to apply the design to the lugs and 7) how to cut out the lugs.
One of the advantages of a group discussion is that others can bring improvements and/or variations to proven methods.
A quick overview of the procedure:
1. A rough sketch is drawn onto the lug to get an approximate idea of what looks right.
2. A flat blank outline shape of the round sections on each lug is cut out from a piece of paper. This results in 6 outlines for 3 lugs.
3. These blank outline shapes are doubled in size and traced onto graph paper.
4. A design is created at least twice its actual size within the blank lug outline traced onto graph paper.
5. Centerlines are drawn or scratched onto the lugs to establish where the design should be placed.
6. The design is xeroxed back to actual size onto some kind of sticky backed paper (that can be bought at hobby, art or drafting supply stores) or masking material (available at sign shops) and placed on the lug.
7. Round shapes and saw blade access holes are drilled out. A jeweler’s saw cuts close to the lines and Swiss needle files (primarily) are used to file to the line.
Here are a few pictures of lugs my students have cut out in framebuilding class. The 1st set sitting on the table is Noah’s. The 2nd picture in the fixture are Richard’s carved lugs. And the last two pictures of Art Deco lugs already brazed into a frame are Amanda’s (check out her nice clean shorelines!).
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