When I first purchased my minilathe one of the first projects I attempted required drilling 4mm holes 50mm deep into round mild steel bar. Drilling the first 10mm was easy but as the hole gets deeper then the drill must be withdrawn frequently to clear the swarf that accumulate in the flutes. Failure to do this slows the whole process down, the drill heats up and becomes blunt and there is the possibility of the drill jamming and breaking. On the other hand, withdrawing the drill every few seconds is also slow and tedious. Whilst doing this operation I pondered on how this operation could be performed more efficiently and I started to imagine a feed arrangement a bit like a drill press on its side whereby the drill could be advanced into and withdrawn from the bar by moving a lever.
展开▼
