How to Design a Lug and Make It Look Nice

(This post is another in a series of posts on frame building)

After we put all the mitered tubes in the jig, we slipped on all the lugs that would connect the various tubes. I used Henry James lugs and bottom bracket, which all worked fine after some mild filing and a tiny bit of bending... all but one.

The head tube to down tube lug was too shallow! It was so far off we had to order a custom, blank lug, which I had to file into shape to make it match the other lugs.

This post is about that process.

One of the reasons you buy a built-by-hand bike from a master is for the detailed, custom lug work. A professional is able to make intricate designs that are both sharp and thin, whereas a factory lug might be thick, and rife with imperfections. 

This is the template for a lug that Herbie of Helm cycles was working on. 

Here are the blank lugs. The design is taped on top and used as a cutting guide.

Here's my lug, put in the jig to make certain it fits. 

My lug is put on the lug-vise and prepared to be cut.

This is a jeweler saw, the device you use to cut the shape into a lug. I broke about a thousand of those little blades making my lug. 

Little jeweler files are used to get into the nooks and crannies. 

Here's a lug made by Herbie. 

My lug, with a few cuts

This is the rough shape after cutting with the jeweler saw. Now I have to finish the job with files. 

The final lug, here, took about 10 hours to make, most of which was done after class. If a simple lug like this takes 10 hours to make, imagine how much time Herbie spends on his crazy arabesque lugs.