Hi, everyone, recently I‘ve been in need of new cones, but I just find that all the bicycle stores sell you all the set or kit complete, no the cones and if somebody does the price is too high and not convenient, so I was thinking to making from scratch, with the help of my uncle and his lathe but with the surprise that the measure of the threat is something between 3/8 and 10 mm, so nothing exactly, I didn‘t know that!!, so maybe they have they own measure tool (tap), however I‘ll like to hear the opinion and advice for someone who know something more about thisRecently and by the use my cones worn out or crack, I am a heavy/serious bicycle user, but the only I need to change is the cones and sometimes the bearings, but not the axle, thanks in advance for your commentaries and adviceshave a great weekend
If you are able to turn new cones then I hope you understand that they must be hardened, then the bearing surface must be ground. I am sure you have the proper measuring tools to copy the radius of the old cone to the new one. If you are able to do all of this then you should be able to put any thread you want on a 3/8 rod and then match the cone thread to it. Don't forget to make locknuts and axle nuts as well. Most, but not all, axle threading is 3/8-24 but there are instances where it is M10. Believe me, it is MUCH cheaper to purchase a new axle set. but doing what you propose would be a fun experiment! EDIT: The answer from nodope is pretty much wrong about the tolerance required, sorry to say, unless you are machining sealed or shielded bearings. Neither the cones nor the cups require that type of precision since they are generally machined with 1.5 to 2.5 times the radius of the ball itself, allowing the bearing to touch at just a single point which facilitates adjustment and error correction. To be more realistic he should have reduced the fractional measurements. For example, 50/1,000,000 is the same as 0.000005 which is ridiculously WRONG.
Look for scrap wheels which may have a trashed rim yet the bearings are often new inside with the original manufactures grease. As long as the axles are the right thickness and length plus cone type any wheel will do. To avoid cone wear use Oregon Two Stroke chainsaw grease and oil as it repels dirt, a useful feature on bearings.
