The Proteus Framebuilding Book - Proteus Bicycles

Recommendations

Info

The other consideration, clearance, is also important. Many touristswant room for clinchers and fenders. In this case you maywant to have more clearance. If so, the brakes you use are not important.This is especially true when Mafac cantilever brakes areused, since they can be brazed on anjA^here along the fork. Onefinal note, longer forks flex more than shorter forks.Fork rake - This is the distance from the center line of thehead tube to the center of the front axle. The measurement mustbe made along a line that passes through the axle and crosses perpendicularto the head tube center line. There are two importantcomponents of fork rake, the length of the rake and the radius ofthe rake. Usually, the longer the rake, the softer the ride willbe. A longer rake will also tend to be more stable. However thelength of the fork rake should be considered with the head tubeangle. For example a very steep head tube angle in conjunction witha very short rake may make a frame too quick to steer, even forracing. The radius of the rake can be considered as the radius ofthe bender the fork was curved with. The smaller the radius, themore shock absorbing the blades will be. Generally, you will haveno control over the radius of the bend. If you ever do have achoice of radius you will be able to make a knowledgeable decision.Front wheel clearance - This refers to the distance between thefront axle and the center of the bottom bracket shell. This distanceis usually the concern of tourists. A problem can arise ifthis distance is too short. Usually the toe clip will hit the backof the front wheel or front fender causing a momentary shock forthe rider during the downstroke of the pedal. There is no set correctdistance for every frame. Crank length, toe clip size, and8
youwhether or not you are using fenders makes a big difference. Toincrease the clearance distance you can do one or any combinationof the following things: increase your seat tube angle, lengthenyour top tube, decrease your head tube angle or increase the forkrake .Chainstay length - This is the distance from the center ofthe bottom bracket shell to the intersection point of the chainand seat stays. This is a very simple variable. Larger stayscreate a smoother more comfortable ride and short stays make fora stiffer more responsive ride.Now that you know how to decide on the variables of yourframe, it is time to begin to draw the plan for your frame. Youwill need some drawing paper, a straight edge, a good protractor,a compass, a ruler and a pencil. If you have access to a realdrafting board, you will have an easier time. In any case, youmust begin your drawing by choosing a scale. You could draw yourframe full size, but there is no real advantage to this, and atthe same time, it will create problems. It's best to use a scalewhere 1 centimeter is equal to 1 inch.Start by drawing in a ground line; this is the line the wheelof the cycle will rest on. Next draw a line parallel to the groundline in the center of the paper as many inches above the ground asyou wish for your bottom bracket height. This line represents thecenter of the bottom bracket. Draw two lines parallel and about13 1/2" above the ground line to each side of the paper. Theselines represent the center of the wheels. 13 1/2" represents anaverage height. If you have your wheels already or are using 700c 'sor tubulars,can take an exact measurement of the distance from9
Page 1: 7PROTEUS DESIGN INC.THE PROTEUSFRAM
Page 5: I would like to thank the following
Page 9: Painting''Metal Preparation 77Apply
Page 12 and 13: Just get ones with metric, or Engli
Page 14 and 15: ,It is not necessary to use differe
Page 16 and 17: .frame more responsive and less ene
Page 20 and 21: Thisthe axle center to the ground.
Page 22 and 23: connecting the center of the bottom
Page 24 and 25: Roadgauge of tubing. Most sets avai
Page 26 and 27: efore any damage will occur. So eve
Page 28: The first miter you will work on is
Page 31 and 32: the bottom bracket shell and hold t
Page 33: Preparing the LugsThe next step is
Page 36 and 37: CenterlineFig. 3If possible, use so
Page 38 and 39: area where the clamp was. Turn the
Page 40 and 41: .8the frame will have cooled enough
Page 42 and 43: .touch anything. You don't have to
Page 44 and 45: kept in mind. First, the style of j
Page 46 and 47: The dropout may be able to swing a
Page 48 and 49: Using the scribe marks as a guide,
Page 50 and 51: Gently remove the wheel. Don't worr
Page 52 and 53: and bend the dropout to correct the
Page 54: that you are ruining your frame. Th
Page 58: .Use a small round file for this. T
Page 61 and 62: crushed. At this point the end shou
Page 63 and 64: especially true with silver, which
Page 65 and 66: emain in the right place and you ca
Page 68 and 69:
.is much easier to work on them whe
Page 71 and 72:
the board. (See Fig. 5B.)Lay the st
Page 73 and 74:
Fixing the 2" x 4" axle assembly to
Page 75 and 76:
Correct blade angle ,. WrongangleFi
Page 77 and 78:
the right and left measurements are
Page 79 and 80:
ItLots of points, you may want to s
Page 81 and 82:
the lugs and fork crown. For final
Page 83 and 84:
PointsNext, using a curved or large
Page 85 and 86:
frame. Two popular styles are domed
Page 87 and 88:
IPaintingrub your fingers over all
Page 90 and 91:
.necessary to use small pieces of s
Page 92 and 93:
Fig 2
Page 94 and 95:
.wascomplete.Applying the PrimerA p
Page 96 and 97:
.ofthink it'd be clean. Chances are
Page 98 and 99:
a similar method. At- this point it
Page 100 and 101:
To..only exposed a few tiny spots o
Page 102 and 103:
Peoplepaint to give a bright, shiny
Page 104 and 105:
OneAcrylic.and the frame can be bui
Page 106 and 107:
the frame members apart. The diffic
Page 108 and 109:
\bottom bracket or the seat tube ou
Page 110 and 111:
Seat & Chain Stays 4 piecesFork Col
Page 112:
Proteus Design framebuilders are pr
show all

The Proteus Framebuilding Book - Proteus Bicycles

Create successful ePaper yourself

Delete template?

Save as template?