|This article appeared in Recumbent Cyclist News, Issue #19/20 printed in 1994. Cyclo-Pedia is no longer in business, and the books may have gone out of print.|
It all began when I was talking to Gaylord Hill at Cyclo-Pedia while placing an order for some conventional bicycle parts. In addition to selling me on the benefits of recumbents in general, he mentioned that you could make one from muffler pipe and an old ten-speed! Cyclo-Pedia has both an HPV Parts and a Frame Builder's Catalog ($1 each). The plans for an Econ-Bent are $30. To my unskilled eyes, it looks most like a Lightning P-38. The plans consist of a thirty-page booklet, with a few oversize drawings. (Since I bought mine, a new edition is out, with a few additions.)
The first step was to locate an old ten-speed, preferably one with side-pull brakes. It's best if the front brake cable pulls from the left, and the rear from the bottom. I wound up with a girl's frame Sears Free Spirit. These go for about $25 around here.
The next major component, the muffler pipe, was a pleasant surprise. Meineke Muffler bent it to shape and sold it to me for only $25. My understanding is that Midas would not have done it, because they use pre-bent pipes, while Meineke bends their own. The guys at Meineke also offered to weld it into a bike for me, but I declined!
At this point, you retire to the workshop with a hack-saw and a 10" half-round file and perform surgery. Really, these are the only tools you need. Filing the bicycle steel is tougher than the muffler pipe, but it all goes faster than you might think. The joints are pretty complex, since it's always two cylinders intersecting at an angle. You can't measure everything, sometimes you just file until things look good.
This was the toughest phase for me. The local welding supply houses carry brazing supplies, but they know almost nothing about it. They want to sell you a MIG welder for from $500 to $2000. I took a welding class, but that only covered arc welding and oxyacetylene cutting. (See below)
The bike shop people generally don't remember where they got their welding equipment, or how much it costs. It's just always been there. They do know brazing, but they can't tell you why a MIG welder won't work just as well. To make a really long search short, I bought a Victor portable oxyacetylene torch. It came with brazing and cutting tips and it's own carrying case. The total cost was $360, more than I wanted to spend. You could probably save some money by buying a cheap torch, then going to the welding supply house for "portable" tanks. When the tanks are empty, they cost about $10 each to refill (one tank for acetylene, one for oxygen).
The torch came with excellent instructions. There are several good books in print (see references below). One, Practical Welding, is available at Northern Handyman stores, a good source of welding supplies. You'll also want to pick up a hand-held disc grinder with a wire wheel ($60). This amazing device will clean up any welding splatter in a jiffy, just remember to WEAR YOUR SAFETY GLASSES.
Learning to braze is easy. In part, this is because the oxyacetylene torch produces an abundance of heat, far more than you need. The object is to melt the brass brazing material without melting the steel tubes. Therein lies the distinction between welding and brazing: in welding the steel melts together, in brazing a thin layer of molten brass bonds the steel together. It is rather like soldering, but with brass instead of solder.
The Econ-Bent plans say nothing about welding, but give many hints on how to insure alignment of the pieces being assembled.
It is now that you must spend more money: $4 on electrical conduit (for the seat), $90 for a front fork and head tube (from Cyclo-Pedia), $7 for a bottom bracket shell. The latest plans include some scheme for building your own fork, but I haven't seen them.
Attachment of the various bits requires some guesswork unless you have a finished Econ-Bent to take measurements from. The plans don't, and can't, cover all possibilities. The trick is to take your best guess and move on to the next step.
After ordering a few more miscellaneous braze-on's (hey, this is fun!) you will be ready to paint. Realize that no paint job you do at home will be as tough or as pretty as a factory's. The closest you can come is to use something like Imron paint, but even that requires special skills and equipment to apply (I'm told). The cheapest you can have it done is probably about $100. Since I wasn't sure the thing would work, I just used cans of regular primer and spray paint. It looks OK and I'm not worried about damaging the finish.
By now you have something that looks like a bike frame. I waited until this point to order the remaining parts because I wasn't sure I'd get this far. Now you're spending money fast, but you're on your way to riding a recumbent: front wheel & tire $46, rear tire $17, 3 chains $36, brake cables and housing $10, new thumb shifters and derailleaurs $47 (Cyclo-Pedia). At this point it's really shaping up. Your friends will be amazed (at least mine were). Gaylord will even send you a an Econ-Bent sticker for it.
My nearest recumbent dealer (Morgan's Cyclery, Rocky Mount NC) gave me a test ride on an LWB recumbent once. The starting technique is to put the right crank arm at 12 o'clock and push off with your left foot. The same thing works on SWBs. The initial rides were scary. The steering is very sensitive until you get used to it. You can hit the front wheel with your heel in sharp turns (usually at slow speed). You can relax your arms or use them to lift yourself slightly to ride over rough spots.
How does it compare to a regular bike? It's very fast on the level, but seems to use different muscles than those I developed for regular bikes. It's heavy (40 lbs.) and going up hills is tough. When I buy some new cogs for the intermediate drive gears this should improve. Weight distribution is roughly 72% front, 28% rear - if I built another one I could do a little better. It's hard to know what dimensions are important from the plans alone, and I could have moved the rear wheel forward several inches if I had known.
I spent at least $340 for parts and about $360 on welding equipment. It also took a lot of work and time. (I was almost afraid to finish it because it might not work!)
So much for costs, on the other side of the ledger I had more fun than I've had in years. I think of new non-bike welding projects every day. Even with the welding equipment I still spent less than $700 (compared to a Lightning P-38 at over $2000).
One final note, there don't seem to be many books in print on bike building. The only one I know of is Designing and Building Your Own Frameset by Richard Talbot. It's interesting, but not as applicable to recumbents as you might wish.
Propane with a brass nozzle - Not enough heat.
Propane with stainless steel nozzle - Lots more heat than the simple brass nozzle, but still not enough. Some of these can use MAPP gas as well. MAPP gas is hot, but you don't get much control with the broad flame these generate.
Oxy-MAPP - The advantage here is that small disposable tanks of MAPP gas and oxygen are available at local stores (like Builder's Square). The drawback is that oxygen costs $8 a tank. I'm not sure, but my estimate is that a tank of oxygen might last about 10-15 mins. That could get expensive quick!
AC Arc Welder - You can buy a small arc welder for about $100. This can't be used for brazing (see MIG below), but there is an attachment called a carbon-arc torch that can. It costs about $25. It consists of two carbon rods held close together. When the spark jumps between them the heat it generates can be used to braze. Unfortunately, as the rods burn down you must slide them closer together. This can be pretty tricky while you're working on a big joint. It also seems to spray carbon dust on the work, and cleanliness is important for a good brazed joint. In short, I couldn't get it to work.
Oxy-Acetylene - The cheapest torch kit is about $100 and add $100 for small tanks. You'll need a holder for the tanks (for safety reasons) and $10 each to fill the two tanks. You may also need to pick up an adapter when you buy the small tanks. One of them takes a fitting different than the more common large tanks.
MIG welder - This is an improvement over the simpler "stick" electrode welders. The welding rod is a small wire that is fed into the work with a trigger. The problem with all arc welding is that the amount of heat generated not only melts the steel, it also warps everything near it. On a bike, this is unacceptable. Plus, although the muffler pipe is pretty tough, most bike tubes are so thin they would just burn through.
TIG welding - From what I'm told, this is the dream tool. It's uses electricity to generate a controllable flame, protected from the air by an inert gas. Unfortunately, you just left my price range!
Hire a Welder? - This might be an option, but there's plenty of setup to do between brief periods of welding. Hiring a pro could get expensive.
Finch, Richard and Monroe, Tom. Welder's Handbook. HPBooks. 1985.
Geary, Don. The Welder's Bible, 2nd Edition. TAB Books. 1993.
Talbot, Richard. Designing and Building Your Own Frameset. Manet Guild. 1984.
Scheck, LeRoy and Edmondson, G. C.. Practical Welding. Glencoe/MacGraw Hill. 1984.
(These books were still in print in 1994.)