DRILLING GEO.
	Post Reply		Forum

Replies to this message

Re: DRILLING GEO.
Re: DRILLING GEO. -- NDR	Post Reply	Top of thread	Forum

Posted by: randykimball ® 12/11/2005, 10:51:05 Author Profile Mail author Edit

Thinning the web will make a drill take less force to travel into the work, but a thinned web may break easier. So this depends on the material. When drilling through thin material it is often wise to flat the lands. This is to grind a small flat on the cutting edge that is vertical so that when the drill goes through it has less tendency to grab and "screw" itself through the work. We have all experienced this with a hand drill motor at home. The angle of grind at the point will effect the tendency the drill has to walk. The shallower the grind the more the drill wants to stay centered. However this decreases the effeciency in which the drill uses downward forces into the work. As the angle of the grind is increased the effeciency of forces into the work improves to a point. As the grind angle increases so does the area of contact of the lands, thus there is a point of best effeciency. This tends to be around 30°. The helix on the flute spirial effects the way chips are removed from the hole. The grind style effects the way the chips are broken. This becomes a science in some materials. This could go on for some pages as there is much more to the science of drilling than most imagine. The worst suggestion of your lifetime may be the catalyst to the grandest idea of the century, never let suggestions go unsaid nor fail to listen to them. Modified by randykimball at Sun, Dec 11, 2005, 10:56:08

Post Reply | Recommend | Alert

Where am I? Original Top of thread