![]() I've used a strap to hold everything together. If you have a friend, they can help you hold everything together. Position the steerer tube / crown between the forks once more. Fit the new stem into the fork's steerer tube. If you cut the head off the existing stem, you can skip the above steps. Cut the tube so that its length is correct for the steering bolt and wedge. Use the angle grinder to cut a 45 degree cut on the end of the tube. I've chosen to make my own stem, as I had some steel pipe which fits inside the fork's steerer tube. If you like, you can cut the head off the existing stem. Be careful not to get any weld spatter on the bearing races! Next we have to make a stem. Tack weld the base plate to the fork crown. Use an angle grinder to cut the sheet steel so you have a base plate as shown in picture 3. Draw the two outer holes (where the forks go) onto the sheet steel. Make the base plate: Using the cardboard template, cut a shape from some sheet steel. Trim the cardboard so it's a nice neat shape. This will form the template which we'll use for the base plate and the top plate. Using another bit of cardboard, mark and cut holes where the three tubes fit. If you've been careful, it should fit snugly. Next, place the steerer tube / crown between the forks. This will give use the correct width for the forks. Attach the wheel to the ends of the forks. Take your time here, try and get the shape as close as possible to the new forks. Use an angle grinder to cut the shape of the new forks out of the crown. Use a marker to draw the shape of the new forks on the fork crown. Using a bit of cardboard as a template, draw a semi circle around your new fork tubes. Try and get the base at flat as possible. Next step: Build the forks Cut the legs off the forks. Each tube has a drop-out on one end and a threaded nut at the other end. To recap - at this stage we have two tubes. Here's where the time taken to make a straight edge pays off! When your happy that all is well, weld it securely. Luckily, I was able to use another wheel which fitted better, but take heed of this mistake! Pic 7. I only discovered this later during a test ride when a wheel's spokes were rubbing against the inner side of the fork tubes. IMPORTANT: I made a mistake when I welded my dropouts - I placed them right in the centre of the tube - I should have moved them closer to one edge. I used a magnetic mount to hold the drop-out to the fork. (Pic 6) Next, we need to weld the drop-outs to the forks. Keep trying to fit the wheel axle into the slots until they just fit. Your aim here is to cut a slot just big enough for the wheel's axle to fit snugly. Take your time here - don't cut too much of you'll risk the wheel popping out. Clamp the two pieces together and cut out the slots for the wheel axle.This way, you can be sure that when you use an angle grinder to cut the slots, both slots will be identical. Remember, the straighter the surface, the better the join will be. Pic 4 Use the grinder to make the edges neat. I aligned the drop-outs in a clamp and used the grinder to get their edges identical. Angle grinding is never exact, so the drop-outs were not exactly the same. Use an angle grinder to cut out two pieces from the steel to form the drop-outs. This will give an indication of the size and shape of the piece to cut out. Overlay one of the existing fork's drop-outs onto the steel to be cut. I used some scrap steel plate, about 3mm thick. There's no way of attaching them to a wheel, so we need to make some drop-outs. Above all, enjoy building and don't give up! Read on for instructions on how I did it, and the mistakes I made along the way. ![]() ![]() *Access to a pipe bender - you may need this if your angles change significantly and you don't want to cut the extension tubes at an angle. *New chains - if you're extending the frame significantly, the chain length will also increase. I had some 1.4mm thick sheet steel which is perfect for the plates I made. Butt welding tubes of the same diameter is more difficult and will not be as strong unless your an expert welder (and I'm not!). The diameter of this tubing should be either slightly smaller than the existing frame tubing (to fit inside the cut tubes) or slightly bigger (to fit over the tubing). *Steel tubing to extend the frame after chopping. These need to be quite heavy gauge as the forces involved will tend to bend the tubes. *Welder (I used a gasless MIG welder - a Clarke 105EN) *Steel tube(s) for the forks. I took a 25 year old Raleigh Wisp ladies racing bike and converted it to something a bit out of the ordinary. I've recycled as many parts as possible, and used scrap materials when I could. The main inspiration for this came from AtomicZombie and Koolkat's instructables. This is an instructable on how to build a chopper bike on a budget.
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