Frame Jig.

In the mid-1980s I commissioned Photographer Mike Graves to take some photographs of my frameshop. Above is a picture of my frame jig used to assemble frames. My work area was not as messy as it appears here, but Mike took some artistic license and added some extra tools and fixtures to compose a more interesting picture.

The picture does however give me an opportunity to explain what was going on before Mike took over to create this picture. Frames were made in three separate parts, the main triangle, which is not actually a triangle as it is made up of four tubes. Top and down tube, seat tube and head tube.

The second part is the rear triangle, made up of chainstays, seatstays, connected by the rear dropouts. The third part is the front fork that is assembled on a separate jig not shown here.

The main triangle was assembled here then fully brazed out of the jig to allow the metal to expand and contract freely. There is less distortion and built in stresses that way.

The main triangle is fully brazed at this stage. The lugs have yet to be filled and polished, but the surplus head tube has been cut off and the head tube has been machined ready to take a head bearing. The excess seat tube has also been cut off and filed to the shape of the seat lug.

At this stage the rear triangle is being assembled, so that it matches up with the main triangle.

This is evident by the seat stays left long at this point, to extend beyond the seat lug. (Pictured right.)

The seat stays at the rear dropout will be tacked in the jig, then fully brazed out of the jig.

The seatstays will be later cut to length and a machined seatstay cap will be brazed into the seatstay top end.

The main triangle and the rear triangle will both be finished filed and polished separately, because they are easier to handle and manipulate in a bench vise as separate smaller parts.

When the two parts are ready, they are assembled and brazed out of the jig to accommodate the distortion due to heat. Because the main and rear triangle were initially assembled in the jig, they will fit accurately out of the jig for the final brazing.

This modified vise-grip (Above.) has two pieces of angle iron brazed to the jaws, these clamp onto the seat tube. A short piece of round tube is welded to one side, at right angles to the seat tube.

The seatstays are then clamped to this tube on the fixture with two engineers clamps. One shown here. (Left.)

The chainstays are held in place at the bottom bracket with a vise grip on the chainstay sockets.

Alignment tools are used to make sure a wheel will sit central in the frame.   

Frames like the Fuso were made in batches of five frames all the same. So the set up in this picture will be used to make five rear triangles, for example. Each stage of the assembly process is repeated five times. With one exception.

Front fork blades, and chainstays were identical no matter what the frame size, so these were prepared ahead of time in batches of 20 or 30 pairs. Fork blades were bent (Raked.) slotted, tips brazed in, then fully filed and polished and cut to length.

Chainstays were cut to length, slotted, and the rear dropout brazed in. Followed by filing and polishing. One extra item, the right chainstay is flattened on the inside to clear the sprockets when the rear wheel is removed.

This is where this little tool comes into play.

The thin end of the chainstay was placed in one of the slots, heated to a red heat, and hammered flat with a small hammer.

This was done prior to slotting the tube to receive the rear dropout. 

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Capillary Action

David R. Ball Photo

Capillary Action is one of those laws of physics that most people know exists but don’t think about too much. It is the reason a paper towel or a sponge will soak up water. It is the reason a wick in an oil lamp draws the oil upwards, defying gravity, to the flame where it burns.

However, it is not just soft fibrous materials that have these properties, a clay flower pot or a clay brick will soak up moisture because it is porous. It occurs in any situation where there are tiny gaps or fissures between otherwise solid materials, any liquid will be naturally drawn through that gap.

When a framebuilder is brazing a lugged joint on a bicycle frame, it is capillary action that draws the liquid molten brass through the gap between the tube and the lug. If the tubes are mitered correctly, in other words the end of one tube is cut to precisely fit the curvature of the tube it butts up against, it too leaves another tiny gap between the two separate pieces of metal.

The molten brass will also be drawn between this gap to actually braze one tube to the other inside the lug. The final result is a strong joint, but one that spreads the stresses over an area.

When joining metal, in this case steel tubing, there is a need for the tubing and the finished joint to be of somewhat equal strength. If the joint is much stronger than the tube, the tube may fail adjacent to the joint. Conversely, if the joint is weaker than the tubes, the joint will fail.

The above picture is me brazing the main triangle of a frame together. In particular, I am brazing the head lugs. I am using an oxy-acetylene torch as my heat source. I used a fairy small but very hot flame, which allowed me to pin-point the heat where it was needed.

Metal when heated becomes red hot. A dark cherry red first. This is the temperature silver solder melts. I used brass for all brazing of the main joints so this melted at an orange red color. Temperature was controlled by constantly moving the torch on and off the part I was working on, and the color of the hot metal was my temperature guide.

In my right hand is the brazing torch, and a small hammer. I am not actually using the hammer, although at first glance it might appear that I am. It is just there in readiness should I need it. In my left hand is the brass filler rod. I am heating the top head lug and the top tube, and when it reaches the desired temperature, I feed in the brass.

As I feed in the brass, I watch for it to flow through the lug to appear on the head tube. You will notice the head tube extends beyond the head lugs by an inch or so. When the lug is full of brass, (I know it is because I saw the brass flow from one side to the other.) I flow out all the lug edges and any surplus brass is flowed out on the head tube where it extends beyond the lug.

This will later be cut off as scrap. Working in this fashion there is very little excess brass to clean up after. There is a similar situation at the seat lug where the seat tube is left sticking through the seat lug, to be cut off later. Again, excess brass is flowed out onto the scrap portion.

Brazing different thicknesses of steel together can create a problem. For example, the front and rear drop outs. These are of course much thicker than the tube it is slotted into, and if you come in with the flame at the point you need to braze, the tube will almost immediately glow red hot, whereas the drop out itself is still relatively cold.

The trick is to heat the dropout away from the tube, wait for it to turn red, then move towards the tube, which will quickly glow red to match the pre-heated drop out. When the first drop of brass melts and forms a bridge across the two separate parts, it magically becomes one piece of metal and all glows evenly at the desired orange-red color.

One cannot see how much brass is flowing inside the tube where the tang of the dropout reaches beyond the slot, unlike the lugged joint where the framebuilder can see the brass flow from one edge of a lug to the other. However, the builder gets a feel for how much filler rod is going into the joint to know whether it is full or not.

Finally, what is that little hammer for? Well, lugs usually come in standard angles of 73 degrees. But not every frame I built was those exact same angles. So when I assembled the frame and pulled the lugs to the desired angle it left a little gap on one side.

As soon as the lug was heated it relieved any stress, but there was still a little gap to contend with. A quick switch of hands, moving the brazing torch to my left hand, keeping the joint heated and a quick tap-tap with the little hammer in my right hand closed the gap in the lug. Then switching back to as I was, I continued brazing. No loss of heat or time while I searched for my little hammer.

A little refined blacksmithing if you like.

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In search of the perfect fork blade

When a fork blade comes from the tube manufacturer’s factory, it is straight, the framebuilder bends it to a curve that suits his requirements. 

An un-raked road fork blade is oval at the top. The oval section runs parallel for about a third of its length.

Then the cross section becomes round and starts to taper gradually to its smallest diameter section at the bottom end.

The fork blade is bent cold on a curved form that is sometimes made from hard wood. I used one I made myself from two heavy-duty steel fork blades, bent in the desired curve, and brazed together side by side. This made a natural grove between the two blades where the blade would sit as I was bending.

I would slip a short piece of tube over the thin end of the form and the blade I was bending. This acted as a collar to hold it in place. Then I'd start bending, first by pushing down by hand. The thin end of the blade bends easily, and I would finish off by squeezing it in a vise.

Bicycle tubing is hardened, and it will spring back after bending. Because of this, the form needs to be a greater curve than the finished fork blade will be. 

A fork blade is several inches longer than it needs to be. The framebuilder chooses where he will put the bend, and where he will cut to length. For example, if I were making a criterium frame and wanted a very stiff fork, I would cut from the bottom, thin end.

If I were building a touring frame, and wanted a flexible fork for a more comfortable ride, I would cut from the top end and leave the blade thin at the bottom end. The framebuilder creates the perfect fork blade, by selecting the best place to bend the blade, and by choosing how much to cut from either end.

It is rather like a furniture maker choosing where to cut from a piece of wood to achieve the best end product. Once I arrived at the perfect fork blade, it was then an easy matter to repeat the process again and again.

On a John Howard

On a Fuso

On a Recherché

One exception to this process was the Reynolds 753 fork blades. 753 was heat treated to a degree that the material could not be bent after. These were bent at the factory, then heat treated, and the framebuilder then cut to the required length. You will notice on the 753 Fuso Lux frame (Pictured below.) that the fork bend is a different shape than the ones bent by me.

Chainstays and seatstays are also tapered and the same selective cutting to length is employed. In this case, where the cut is made depends a great deal on the size of frame and its end use. 

The perfect fork blade is stiff enough to allow precise handling, but with some flex to absorb road shocks. It also looks pleasing to the eye. I have a theory that when something is designed correctly from a functional standpoint, it has a natural aesthetic beauty. This is true of a boat, a bridge, a building, and even a bicycle frame.

The modern trend of building straight forks of course saves the framebuilder a great deal of time and effort. If this look has become acceptable, why should today’s builder go through all the time consuming process I have described here? 

The straight blade is angled forward so the same fork rake or offset is achieved and handling would be the same. I can’t comment on the shock absorption qualities because I have never built a frame with a straight fork.

In my view, a great deal is lost aesthetically, so where does that leave my theory about function being linked to aesthetics? On the other hand, is it simply that beauty is in the eye of the beholder?

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Prices then and now

Above is a retail price list for my bikes in 1990. The most expensive is the Fuso Lux which was custom built to order, with chrome plating, and retailed at $3,150 equipped with Campagnolo C Record components. This was probably the most you would pay for any top of the line racing bicycle.

I say this because my competition back then were the Italian imports like Colnago and Pinerello. You would pay a something over $3,000 for one of these lugged steel Italian bikes equipped with the same Campagnolo C Record group.

My production was only a fraction of these much larger companies, they probably each produced far more frames in a month than I did in a year. But I was able to compete because I had a much lower overhead, and I did not need a distributor to sell my frames in the US. It was the shipping and middle man cost that the Italian companies had to deal with that allowed me to compete.

I attended the big bicycle trade shows each year, and gradually built up a network of bicycle dealers all over the US. I could then sell and ship direct to them. My competition, the Italian bike builders, could not do this. The shipping costs alone on individual bikes or frames would have been prohibitive.

They had to ship frames over by the container load to a distributor, who would then market and sell to the individual American bike dealers just as I did. The Italian import frames were mostly built on a system made by a company called “Marchetti and Lange.” This was a conveyer track system, where the frames were completely assembled, front and rear triangle, and “Pinned” together, then placed on the conveyer.

Gas jets pre-heated first the bottom bracket area, the conveyer then moved on, with the bottom bracket and tubes glowing red hot from the pre-heating, and an operator quickly hand brazed the bottom bracket. While this was happening, gas jets were pre-heating the head lugs. Then the conveyor moved on to a second operator who would then braze the already pre-heated head lugs, and so on until a completed frame came off the other end.

By comparison I brazed together batches of 5 frames at a time, using a hand held oxy-acetylene torch with no pre-heating. This meant less heat went into the tubes, so the Columbus tubing retained more of its inherent strength. I don’t mean that the Italian frames were over-heated, but just a larger area of the tube beyond the lugs was heated, due to the use of pre-heaters.

The Italian frames came off the Marchetti and Lange track, were cleaned up and went to be chromed and painted. They mostly left the factory, with the bottom bracket threads not cleaned out, the BB and head tube were un-faced, and the frames were unchecked for alignment.

This work was done after the frames arrived in the US, either by the distributor, but most often by the bicycle shop. Any top of the line bike shop in the 1980s or 1990s had a full Campagnolo tool kit in a wooden case.

By comparison, I would braze 5 bottom brackets, check for alignment. Braze 5 head tubes, check the alignment, and so on. Every frame had the BB thread tapped and faced, and the head tube was reamed and faced ready to accept the head bearings. The seat tube was reamed, so the seat post would slide right in. All this was done before painting, along with a final check for alignment. When a dealer got the frame it was ready for assembly.

What I find interesting is the price comparison from 1990 to now. The most you would pay for a top of the line race bike was a little over $3,000. You might go to $4,000 for something special like Columbus Max tubing. (Picture above.) However, this would be an exception. Today a top of the line carbon fiber Colnago or Pinarello can set you back $12,000.

The average income in 1990 was $29,000, today it is more than 2 1/2 times that at around $73,300. A Ford Mustang convertible cost $14,250 in 1990, today it would be less than twice as much at $25,500. So the cost of a CF bicycle today would almost buy you a Ford Mustang in 1990. Whereas the cost of a Ford Mustang is less today when compared against income.

Back when I built frames, as a small individual builder, I could compete with the larger import companies and still make a fair profit. Today, top of the line bikes are made by large corporations, and prices are not based on what it costs to produce, but rather by what the market will stand. With a consumer, it seems, who would rather pay more, if only for the bragging rights.

Previously posted in Feb. 2014. The price comparisons have been updated to reflect today's figures. It seems CF prices have dropped since 2014. Could it be consumers are balking at these over inflated prices. What do you think?

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Functional Art

Can a bicycle frame be considered art? The term I always use is “Functional Art.” Anything manufactured whether it is made by hand or mass produced, can be considered functional art.

Furniture for example, a chair in order to serve its purpose has to be comfortable to sit in, but when it comes down to making a final choice, quality, and appearance will play a big roll. 

Aesthetics and function go hand in hand, hence the term Functional Art. If someone made a musical instrument that looked beautiful but sounded awful, what use would it be apart from something to hang on the wall and look at? Likewise, the beauty of a well-crafted bicycle is in the way it rides and handles 

When I built frames in England during the 1970s my customers were almost exclusively racing cyclists. They bought my bikes because they handled well and were reasonably priced. On moving to the US in 1979 and I saw that framebuilders paid a great deal of attention to detail and finish of the product, because their customers were swayed by aesthetics as much as what was beneath the paint. 

To take this discussion one step further, does the individual craftsman or artist inject something of himself into whatever it is he is making? Does he breathe life into an inanimate object and give it a soul almost. How else does one describe a feeling?

A handmade musical instrument by a known and respected craftsman will feel different when played and sound better than a massed produced factory made item. How does one describe the difference? 

How do these qualities get into the musical instrument other than through the artist? Through his design and skill. I will go so far as to say there is a part of me in every frame I built. Also when you practice a skill long enough it becomes second nature, automatic without conscious thought.

This is not a new notion, the Native American called this “Hand Magic.” Nature bringing something into creation through the artist’s hands. When an ant colony builds an ant hill, is this any different from man building his cities and roadways? Just on a larger scale. 

The Navtive American sees mankind as part of Nature, not separate from it. There is nothing in Nature that is not beautiful. One can dive deep into the ocean and find beauty, or go to places where humankind rarely travels and find the same.

The only ugliness is man-made. Man builds a barn in a field and paints it red. It is an eyesore, a blight in the environment. Given time the barn becomes derelict, nature takes over and the barn becomes a thing of beauty. Photographers come to photograph it, artists come to capture it on canvas.

If the artist is connected to the creative source in the first place then his creation will be beautiful to begin with. It is not even necessary for the artist to be aware of this.

When I built frames some thirty years ago, had anyone put forward this point of view to me, I would have said they were full of crap. It was only towards the end of my framebuilding career in the late 1990s did I realize that all creativity or art comes from one source only. Be it music, painting, or even bicycle frames.

To put it another way. Back in the 1980s when I was building frames, there were many import frames coming in from Italy and other parts of Europe, as well as Japan. These would be built in factories, usually by a team of builders. One would braze bottom brackets, another head lugs and son on.

Some would be more conscientious than others, but to most it was just a job, a pay check.  Does it strain the imagination too much to see that frames built in this manner can never consistently measure up to those built by an individual builder, whose life passion is framebuilding, and his reputation rests on every frame.

I am just putting forward my thoughts and ideas. Not trying to convert anyone to my way of thinking. If you disagree that is fine, and I would be pleased to hear your point of view.

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