Construction of a snow park rake for use in your back yard or in my case the new Afriski park being designed and built by members of snowboarder.co.za in Lesotho's Maluti mountains. Visit Afriski.com and snowboarder.co.za for more information about snowboarding in South Africa.
Step 1: Supplies
In South Africa we use the METRIC system so all measurements will be in SI units i.e. mm or millimeters (jfgi).
I used a piece of scrap metal roughly A3 which is 430mm x 300mm and 3mm thick.
Some paper for rough calculations.
Pen, ruler and 90 degree set square.
Three drill bits 5mm, 8mm and 11mm in diameter (I prefer to progressively widen holes drilled in steel than go to the final diameter).
Step 2: Dimensions
I did about half an hour of research, looking at what pictures i could find on the innerwebs and thinking about what my requirements were.
I had a piece of steel lying around which looked the suitable size and did my design from there. I chose my teeth size from rough drawings and approximately divided the size into the length of my work piece. I also decided to design a rake that was easy to cut out with a hacksaw and the fact that not much natural snow falls in Southern Africa so the snow tends to be dense and icy. The sharp teeth are quite aggressive and could be rounded for use on softer snow. Also if aluminium (this by the way is also the correct spelling of the element listed as "Al" in the periodic table of the elements) is available it would make a lighter rake that wont rust. I think it would also have to be approximately 6mm thick to have the same strength as steel.
My final dimensions for the teeth were 50mm high x 40mm wide with a ~11mm drill bit used for the rounded parts. Total width of the rake is 430mm. This made 11 teeth with the two outer ones 5mm thinner than the rest.
Step 3: Drilling and Cutting and Bending
Mark out your design on the steel and drill and cut. I had my final piece bent at a factory but one could use two pieces of steel and bolt them together or another clever way. Note that this rake is not going to the moon or going to be used to perform brain surgery so feel free to use this instructible as a very rough guide to build your own.
Step 4: Final Stages
Find a suitable handle. I had a piece of aluminium lying around from a fire staff that i made, it is a bit short but will have to do for now. Mark two holes in the rake, drill and do the same to the handle and bolt together. I painted mine for a bit of rust resistance.