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drill bits
JoelP - 7/2/10 at 08:19 PM

i have a set of drill bits that i thought were ok, they've lasted a while when being used in a pillar drill. Now i've been drilling a few holes with a cordless and they are going either blunt or snapping the corners off the tips, after just a few holes. The cordless isnt turning particularly fast, but obviously wobbles more. Is there any particular reason for this?! I have loads more to drill.

Cheers.

Tatey - 7/2/10 at 08:23 PM

Are you drilling steel with the cordless? I started off drilling steel with my hand held drill and snapped no end of bits and barely managed to drill any holes, i thought they were really crap bits, but then i decided to get myself a pillar drill and they drill perfectly now. I'm not entirely sure what was causing the bits to drill really badly or snap though.

JoelP - 7/2/10 at 08:34 PM

thats my exact problem. Think i'll have to use the pillar, and drill everything in advance! Cheers.

rusty nuts - 7/2/10 at 08:35 PM

Are you holding the drill at right angles to the surface being drilled? A pillar drill would probably be at right angles. I still have a set of cobalt bits in everyday use that I have had for best part of ten years , still going strong

Ben_Copeland - 7/2/10 at 08:45 PM

Your either drilling at the wrong angle ie not 90 degrees Or your pushing too hard on the bit.

[Edited on 7/2/10 by Ben_Copeland]

JoelP - 7/2/10 at 08:53 PM

ah... im definately pushing hard, and definately not 90 degrees!

Lesson learnt, will get the pillar drill fired up!

NigeEss - 7/2/10 at 09:17 PM

Are you going flat out too ?
Get slower as the bit goes bigger. And I find you need to go up in more steps than with a pillar drill.

britishtrident - 8/2/10 at 08:50 AM

Depends what you are grade of material you are drilling, modern tin top car body work can be surprising difficult to drill. particularly on some of the steel pressing on BMWs and the Rover 75 are almost impossible drill with a hand held electric drill even with top quality drill bits.

I jest not it is like drilling tool steel, a bit of a culture shock as I can remember how soft the steels on some BL cars were.

sucksqueezebangblow - 8/2/10 at 09:29 AM

Also a good idea to lubricate the bit with cutting fluid (Suds), or a good substitute is WD40. Also the larger the bit the slower the speed you should use.

x-generator - 8/2/10 at 09:18 PM

quote:
Originally posted by sucksqueezebangblow
Also a good idea to lubricate the bit with cutting fluid (Suds), or a good substitute is WD40. Also the larger the bit the slower the speed you should use.


Have to agree: use cutting fluid - don't push let the tool do the job - never let the tip get too hot.

x-generator - 8/2/10 at 09:21 PM

If you are going through a lot of drills and have a lot of holes to do- it may be worth investing in a drill doctor ( drill sharpener) saves a fortune in the long run.

rusty nuts - 8/2/10 at 09:40 PM

You can buy an awful lot of decent drill bits for the cost of a drill doctor.

x-generator - 8/2/10 at 10:09 PM

quote:
Originally posted by rusty nuts
You can buy an awful lot of decent drill bits for the cost of a drill doctor.


I did ! I bought an awful lot over the years - I got fed up of buying them recently after building my own trailer and drilling through 5 mm angle iron prompted the purchase.

JoelP - 11/2/10 at 08:24 PM

its 3mm angle thats doing me in! Put loads through the pillar drill last night, was so much easier even using a chipped bit!