Use consistent hammer blows, starting from an inch from the edge on both sides, working your way out to the edge. If you don’t have access to a shrinker/stretcher, you can also achieve the same results using a stump or a leather bag.
I shrink along the edge, overlapping my bites, in order to create a consistent and evenly shrunk piece. In order to work efficiently, I use a shrinker/stretcher – this works by producing bites on the piece where the machine comes in contact with the metal. Once the metal is at annealing point, let it sit for a few minutes until it is cool to touch – you are now ready to move on to the shrinking and stretching processes.įirst, in the shaping process, you need to shrink the outside edge to create the curve.
I use a large head on the torch in order to reach a larger surface area – this will allow the aluminum to heat more evenly. Next, turn your oxygen on, to create a blue flame – this will produce more heat. This allows you to tell when the metal is at annealing point (when the carbon layer or permanent marker disappears). Alternatively, you can use a black permanent marker pen to scribble over the sheet and use a propane torch as your flame. This torch works by producing a red flame (straight acetylene) that applies a partial layer of carbon to the metal. I prefer to use an oxygen-acetylene torch to heat the metal. Aluminum ‘work hardens’, which means it gets harder when you work with it (that is when you apply hammer blows).įirst, heat the aluminum in order to relax the structure of the metal, allowing it to become soft. This involves making the metal soft and hard again with the use of heat. In order to create the shape you want, the aluminum has to go through a process called annealing. Once you have cut your piece to size without losing a digit, make sure to deburr the edges, as you will be manhandling it quite a bit throughout this process. As a general rule, I start out with a 600mm x 180mm sheet, which will be ample for a fender to fit a wheel with a front tire size of 100/90-19.Īlways remember it’s easier to remove metal than it is to add metal, so if you’re unsure, always go bigger. This is a good thickness because it’s strong, but not too stiff. To start off, take a 1.6mm thick aluminum sheet. By helping you to understand these principles, you will be able to learn techniques and use them to make any size fender that your crazy motorcycle heart desires.
Two principles that are essential to the metal shaping process are shrinking and stretching. I am customizing this into a scrambler for Wide of the Mark.īefore you go diving into shaping a dustbin fairing that has more complex curves than a 10-year-old has coins stashed in his motorbike piggy bank, it’s best to start with the basics. Here I’ll show you how I shape a motorcycle fender using my 1972 Triumph Trophy 650.
Homemade wood mini bike chopper how to#
If you’ve ever been interested in learning how to shape metal, this is where to start.
Homemade wood mini bike chopper series#
So I’ve found some bike builders I know, respect and admire for their craft.įirst in the series will be my mate, Keeley Pritchett.
The true value of knowledge comes when you share it. In this new series, I want to feature bike builders that have a certain skill that we can all learn from. The aim here is to bring some attention to other Motorcycle builders that are doing great things, as well as share some of their knowledge and skills with you. I learn a lot from my customers and friends in the custom motorcycle space, and I wanted you, the garage builders to be able to as well. An initiative I’ve wanted to kick off for a while is the Purpose Built Moto guest builder series. I know a thing or two when it comes to making a motorcycle fender but sometime’s you need an expert. How to make a motorcycle fender – a guest DIY blog from Keeley Pritchett