The following is a transcript of an article that was orignally published in Cycling Plus magazine. In it, the authors describe how to take a blank set of lugs, and using a jewler's saw and some files, cut your own lug patterns. I would have liked to have scanned the entire magazine page and put it up, but
I do not have access to the originals.
A Labor of Lug
Cycling Plus--February 2000
Looking back, I suppose the idea all started in the forest of dean about 10 years ago, and a chance meeting with two cyclists from Yorkshire. Nothing particularly unusual in that, you might think, but as we chatted about everyday things-the weather, the hills, and the countryside-the conversation eventually turned to bicycles and it was at that point I noticed the extraordinary fancy lugs on their touring frames. I'd seen Hetchins' lugs before but nothing quite like these. Incorporated in the flowing curves and cutouts of the designs were their initials chromed and polished to perfection. "Aye, those lugs were hand made and cost almost as much as the frame," I was told rather proudly as they pedaled away. And that was the end of that-or so I thought. Several years later memories of that brief forest meeting returned when I saw a frame made by London frame builder H.R. Morris, apparently one of only a handful made. The lugs were the most elaborate I'd ever seen-mini works of art and perhaps more at home in a glass case then brazed to a bike frame. Once again they were personalized with meticulously filed initials-not only in the head lugs but also around the bottom bracket. This inspired me further to work out how it was done. Was there some kind of mystical art or engineering skill involved? And, more importantly, could I possible make a set for myself of my own design? After a few weeks of research I decided that the only way to really find out was to get ahold of some blank lugs and have a go. I bought the lugs and bottom bracket shells from Haden Bros. in Birmingham. Described as "plain customizing lug sets," they are made of pressed and welded mild steel, and come in angles of approximately 73 degrees (easily altered by a frame builder) and are relatively easy to file.
File it
Files come in all shapes, sizes, and "cut." Swiss pattern files are available in sizes 00, 0, 1, 2, 3, 4, 5, and 6, with 00 the roughest and 6 the smoothest. For all lug work I found 0, 1, and 2 adequate. Useful shapes include flat, three-square, knife-blade, half-round and round, but there are loads of others (you'll probably end up with quite a collection). Avoid cheap unbranded ones-they break and wear out quickly. Makers such as Stubs, Oberg, and Grebart are all excellent. As far as filing methods go, I'm afraid it's all a matter of learning as you go along. Practice first by filing sample shapes into pieces of mild steel before committing yourself to the lugs.
Art or Engineering . . .
I don't mind admitting that when it comes to engineering I'd be hard pressed to tell a mop from a milling machine but, as I quickly discovered, there's actually very little technical science involved. As most fancy lugs are produced in very small numbers and with so many design variations it wouldn't be cost effective to set up machinery to do the job. In fact, it would be extremely difficult to due the intricate shapes involved, the thinness of the steel, and the considerable problems of holding the workpiece securely. Along with a few basic tools, all you require is a little imagination, creative skills (design and drawing) and reasonable hand-eye coordination-in short a certain level of artistic ability. You'll develop a "feel" for the material-or "medium" as artists refer to it-as you go along. Unfortunately, there is no quick and easy way to learn, it comes with experience and constant practice. One piece of good advice I was given was to pay particular attention to the designs of the lugs. The lug set featured here was intended to be compact and intricate and had progressed from earlier versions that were of much simpler designs. The design and drawing stage also gives you the opportunity to produce something original and personal. In creating my lugs, I've used influences ranging from a bird's head design I saw in a book about Celtic art to patterns in medieval floor tiles and the intricate shapes formed by trees and branches in Epping Forest! The fleur-de-lys-the classic three-petalled stylized emblem of the French crown (and much used in heraldry) has found its way into fancy lug design. If you wanted to create a classic, traditional-looking fancy lug, then the fleur-de-lys would be a good starting point. The tools required are all readily available-a heavy vice (used to hold the bottom bracket and the uncut lugs for drilling and preliminary filing), an electric drill (a bench drill and clamp would be a real luxury), a hacksaw, a selection of HSS drill bits (1.5-6 mm), and assorted files, and some short lengths of tubing (useful to hold the lugs with). I managed to get tubing offcuts of the right diameter from a frame builder-but you could just as easily cut up a scrap frame and remove the paint. Adjustable calipers are handy for checking that each side of the point of the lug is the correct length/height.
Extensions
Extra lengths of tubing can be added to blank lugs and bottom brackets by TIG welding. This produces very neat controlled welds which then can be easily filed flat to produce a strong and invisible joint. Don't be tempted to make the extensions too long (I suggest 2-3cm max.) otherwise the points on the lugs become increasingly difficult to hold accurately when filing. Another factor, which applies more to the frame building side, is the possibility of the lug points extending close to or beyond the butted zone of the tube and so creating a stress raiser. Your frame builder could avoid this by careful choice of tubes but, at the end of the day, it's all going to add to the eventual cost. Expect to pay quite a bit extra for TIG welding, and make sure your welder knows the lugs are made of mild steel. I had a half-finished set of lugs ruined once because I forgot to mention it. He assumed they were made of stainless steel and used a stainless filler rod. The finished welds looked perfect, but were so hard I found it impossible to file them flat.
Getting started: A simple 7-step guide to "lug-cutting"
1.File off any welding/casting seams. Check for any imperfections such as splits or poor welds.
2.It helps to lightly file the whole surface area of the lugs before drawing the design. If they are very thick then some pre-thinning will probably be necessary. Whilst this is very time-consuming, it makes the job of "cutting" your design a great deal easier.
3.Spend as much time as possible on the design, paying particular attention to the center line on the front and top sides of the lugs. (Any mistakes in alignment here show up-especially when the frame is painted and the lugs lined in a contrasting color.) Permanent black OHP marker pens (0.5-1.0 mm) are ideal for drawing on the bare metal. Use them to experiment with different designs and use a small file to make any changes or erase mistakes. This is the fun bit before the serious work begins!
4. Once you're satisfied with the drawing, use a small center punch and hammer to mark the center of the holes you will need to drill. If your design has any cut-outs, then drill holes of a slightly smaller diameter than needed inside the cut-outs (this allows you a margin of error and means you can file outwards for the desired shape).
5. Drill holes close to the outside edge of your design and then use hacksaw and files to reduce the amount of metal, working inwards toward your line. Use the vice or pieces of wood/tubing to hold the workpiece.
6. Regularly check progress by eye and then use of the calipers. By sliding the lug over a piece of tubing you can very accurately assess symmetry.
7. Eventually you'll reach a point where the lugs satisfy all the criteria you set out to achieve. It's now time to find a frame builder willing to take on the task of building the lugs into a frame of your choice.
Building the frame
Today's frame builders work in a highly competitive market. Overheads are high and competition is growing. It's unlikely that a frame builder would be able to build a fancy-lugged frame at the same price as a plain-lugged one. I decided to phone the renowned builder Dave Yates to see if he'd build me a frame. As I expected, he insisted on seeing the lugs before agreeing to take on the job. "There's much more work involved in preparing the lugs for brazing," he explained, "and the other important factor is the number of points and cut-outs in the design." Dave explained how it was important to keep the brazing heat down and to work the filler braze from the main body of the lug outwards toward the points and not the other way around. After Dave had seen the lugs and agreed to do the job, I sent him a frame spec sheet. We then discussed the type of tubing-opting for Reynolds 525. This has a very similar spec to 531 and would build into a strong, rigid, and lightweight frame. Finally, it was a matter of choosing the colors and agreeing on a delivery date. As you can see, the result was more then worth all the time and effort.
Thanks to David Bohm, Josh Putnam, Damon Rinard, Fred Parr, and others whose ideas and information have gone into this page.
If you would like to get in touch with me, please e-mail me at: root@student.uchc.edu
Created September 20, 1998. Last updated February 8, 2003.
visitors since October 2000
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