Goodies



Moulding Hubs and bearings

OK, this is dads idea and making, I take absolutely no credit! Pics and explanation follows: The Heating element has standard Nichrome ( Heating element wire, the ribbon kind ) wire wrapped around it. The basic element is made out of a brass rod, with a central bore. One end of the brass rod has a conical section drilled into it. If you can imagine, the sectional view is in the form of the alphabet "Y", the top part being the conical section, and the remaining part the central bore. The 2 other brass rods seen on the left have the same OD as the ID of the heating element bore. This goes into the heating element so that their shafts sticks out of the heating element. The length can be adjusted by pushing the rod into or pulling it outside the heating element ( In the pics you can see the moulded components, they are of varying size, adjusted by positioning the brass "shaft" rods to the desired length ). The brass "shaft" rod is the RIGHT fit, no play, no gaps.The heating element with the shaft rod is connected to a power supply and is clamped onto a vice ( A piece of cardboard folded over and over again prevents heat to be conducted away by the metallic vice. You'll have to experiment with the plastic material, Polystyrene is a no-no because it's so sticky, it locks up the shaft rod in the element! You can see the material I use, I don't know what it is, but have a feeling it's a form of Nylon and belongs to the end caps of small speakers that my Dad uses.

Slowly feed small chips of the plastic into the heating element and let if fill to the brim. Take a small metallic disc with a small hole in the center and press it onto the heating element ( The shaft of the brass rod goes into the small hole in this metallic disc, careful here, it can burn your hands!! Ask me how I learnt! ). This helps to flatten the end. Turn off, remove from vice, cool under tap, push the heating element down ( Do this on a table ) and slowly pull the moulded part out. The diameter of shaft chosen for the Shaft rods is such that it's a free fit on a 0.8mm or a 0.6mm shaft. The moulded parts weigh NOTHING and work very well. We have tried PVC and it works fine. Please mail me if this all unclear to y'all.