What you want for the concrete is a rotary hammer. A little spendy and
the bit cost is astronomical, but they will bite through granite like
it's nothing in seconds. We use rotary hammers for rohn wall mount kits
going into brick, concrete, and stone. Have only tried the corded
hitachi's, although dewalt has a cordless one I've been keeping my eye on.
http://www.amazon.com/Hitachi-DH40MRY-16-inch-Rotary-Hammer/dp/B000XVINQY/ref=sr_1_4?ie=UTF8&qid=1433378353&sr=8-4&keywords=hitachi+rotary+hammer
is what we've used.
http://www.amazon.com/DEWALT-DCH253M2-Mode-Rotary-Hammer/dp/B00DD1UOTU/ref=sr_1_9?ie=UTF8&qid=1433378421&sr=8-9&keywords=dewalt+rotary+hammer
is the one I've had my eye on.
Josh Reynolds
CIO, SPITwSPOTS
www.spitwspots.com
On 06/03/2015 02:37 PM, Jaime Solorza wrote:
We are trying different brands for 3/32 holes we need for door
contacts and switches. Metal is tough then we hit concrete on door
frame. Slow speeds and oil helps but we eat them up. For concrete
and cinder block walls Hilti drill and bits have no problem.
Jaime Solorza
On Jun 3, 2015 4:26 PM, "Chuck McCown" <[email protected]
<mailto:[email protected]>> wrote:
You can do it by hand with a bit of practice.
*From:* Glen Waldrop <mailto:[email protected]>
*Sent:* Wednesday, June 03, 2015 4:24 PM
*To:* [email protected] <mailto:[email protected]>
*Subject:* Re: [AFMUG] Sharpening Drill Bits
My dad has always sharpened his own, so I tend to do the same.
In my experience, if used in wood they can be sharpened with
little issue. If you drill through metal, buy a new one.
It loses some of the hardness on the edge. It really needs to be
tempered again after sharpening.
----- Original Message -----
*From:* Rory Conaway <mailto:[email protected]>
*To:* [email protected] <mailto:[email protected]>
*Sent:* Wednesday, June 03, 2015 5:18 PM
*Subject:* [AFMUG] Sharpening Drill Bits
We are paying $15-$25 for longer drill bits. When they start
to get dull, just wondering if anyone has had success
sharpening them or do you just buy new ones?
*Rory Conaway **• Triad Wireless •**CEO*
*4226 S. 37^th Street • Phoenix • AZ 85040*
*602-426-0542 <tel:602-426-0542>*
*[email protected] <mailto:[email protected]>*
*www.triadwireless.net <http://www.triadwireless.net>*
**
*“You may be an engineer if your idea of good interpersonal
communication means getting the decimal point in the right
place.” – Unknown*
