#Best drill bit to drill through hardened steel how to
IME, the only "better"/harder drills that work well in a handheld drill are TCT drills intended for use on Stainless Steels (which work-harden very readily) or Hard Plate (here in the UK, I've bought them from locksmiths when I've run into the problem when out on sites, but they really know how to charge).
Either sharpen the drill (a skill that is well worth acquiring) or replace it with a new one, then start again.
If you have no option but to use a hand-held drill, use the slowest speed you can, watch the swarf and IMMEDIATELY stop if the drill stops cutting. Many of us are impatient, bloody-minded types and will persist in trying to drill after the drill stops cutting. This high-pressure contact will cause further work-hardening and the problem will swiftly escalate. If the drill stops cutting, even momentarily, it will skate on the previously-cut surface with the feed pressure spread over a tiny area at, and just behind, the cutting edge. Using a hand-held drill, it can be hard to maintain enough pressure to get the feed necessary. Turning slow and feeding hard with a drill-press is the best approach for most of us. If the feed is correct, the next pass of the cutting edge will get below this thin work-hardened layer and cut the un-work-hardened material beneath. Each pass of the cutting edge does work as it cuts and leaves a thin work-hardened layer on the workpiece.
The feed is important for work-hardening materials. "We" can usually take the speed with a pinch of salt and run a lot slower, as the values are given for production scenarios in which time is money. When you look up the feeds and speeds for drilling, there are both values, feed and speed, given.
0 kommentar(er)
