Introduction: How to Sharpen a Drill for Soft Materials

Picture of How to Sharpen a Drill for Soft Materials

Has this ever happenes to you? You grab a nice sharp drill bit and start to drill some brass ( or anything else soft ) only to find when you break through the backside your drill bit grabs and either breaks or sends your workpiece on a ride? Read on....the solution is very simple.

Step 1: Drill Bit

Picture of Drill Bit

So you have a drill bit. Freshly sharpened and ready to go. I am using a large drill so you can see the modification to the cutting edge.

Step 2: Grinding

Picture of Grinding

Using your bench grinder, with very little pressure, grind the cutting edge flat. You must use the side of tbe grinding wheel for this. This is onlyca touch to flatten the cutting edge. This is called Brassing Off.

Step 3: Finished

Picture of Finished

Now your drill will look like the pictures. I retouch on the grinder to re-sharpen cutting edge. Now you are ready to drill soft materials such as brass without the bit grabbing on the way through. This is usefull for plastics as well. Hope this little trick is helpful!!


VadimS (author)2014-02-14

I'll be spending some time Tuesday sharpening bits at work.

Think this would work for sheatmetal (about 1/16")?

cutprogram1 (author)VadimS2014-02-14

For thin gauge sheet metal put a piece of wood under or behind as a backing for the drill to go into. If you can screw or bolt metal to wood. Sheet metal on a drill press quickly can turn into a rotating knife edge!! Be careful

pfred2 (author)cutprogram12014-02-15

Use a Unibit for sheet metal. Larger diameter twist drills do not work well in thin stock. Even the cheap knock offs are not too bad. Better than twist drills at any rate. I have both. The real thing is a bit nicer.

VadimS (author)cutprogram12014-02-14

I knew about the wood, these are large industrial control panels, and few drills would have the torque to turn them.

I drill holes before using a Greenlee hole punch, so the holes don't need to be clean.

I was just looking for a way to make it a bit easer, I really should be using a corded drill as the old cordless ones we have don't have the power and catch on the metal.

metalbasher (author)2014-02-14

Standard angle for drill bits is 118°.. good for most metals and wood. steeper angles like 90° are used for softer stuff like brass and plastics. wider angles like 135° is used fit the hard stuff, stainless steals.

cutprogram1 (author)2014-02-14

I have always had good luck with a good old fashioned step drill in sheet metal. I do a lot of work on cars and sometimes you just cannot beat them

rimar2000 (author)2014-02-14

WOW, I didn't know this. Thanks for sharing.

pfred2 (author)2014-02-14

What I'm seeing does not match what I think you're saying so I guess I'm not getting it.

cutprogram1 (author)pfred22014-02-14

In step one photo 3 shows a drill not brassed off. The following steps ( I hope ) show position and what drill should look like when done. A very small "flat" on the leading edge or cutting edge of drill bit. Hope that clarifies a bit.

Fikjast Scott (author)2014-02-14

Also - Plastic, I needed this information, great job

I have used this method for plastics, soft non ferrous metals and even some rubber body mounts I had to drill a while back. Glad it helps

About This Instructable




Bio: I am the co-director, co-founder and lead instructor for the Customs for Urban Teens Program (CUT Program). Started in 2009 we take at risk youth ... More »
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