On Sat, 21 Jun 2014 22:27:50 -0500, "Pete C."
wrote:
micky wrote:
Masonry bits. vs. Hammer drill bits
I had assumed they were the same. Maybe not?
Hammer drill bits seem very expensive. The cheapest was $4.50 and I
think that one was small. A lot are 40 dollars or more. That's more
than the drill was.
Masonry bits are intended for rotary drilling only and use cheap carbide
and other cheap materials. Hammer drill bits look similar, but use
higher grade materials to withstand the percussive forces of a hammer
drill or rotary hammer. If you put a cheap $5 masonry bit in a hammer
drill or rotary hammer it will be destroyed before it even finishes the
first hole.
A friend of a friend borrowed my hammer drill. They didn't ask for bits
and I wouldn't have had any anyhow. It came back with a little white
dust in the chuck and the message that it didn't work for what they were
doing. Maybe because they didn't have the right bits.
This means if I need the hammer part, I'll probably have to plan a bit
further in advance.
The drill came from Harbor Frieght. Has a Jacobs chuck which I don't
think is designed for SMS bits, and since the chuck is barely longer
than any other chuck DOESN'T THAT MEAN THAT AN sms BIT WON'T WORK IN IT?
In fact it's not even labeled a hammer drill. It's called an Impact
Drill. (Maybe I shouldn't have bought it, even for $15) **
The drill cost only about 15 dollars, varialbe speed, reversible, and
switchable to a regular rotary drill, but isn't one of the ones they
sell now. It's all blue with black trim, no metal part to the case (not
counting the chuck) . The brand is "Drill Master. "
And I used it Friday to remove two screws from a lawn mower that would
come out with torx or flat. I wanted the drill to go SLOWLY, BUT IT
WOULDN'T, no matter how careful I was. It would go at different speeds,
but none were slow. My Sears variable speed reversible that's 40 years
old will go slowly but I think its max speed is lower than one.
Reversible run CCW with a left-handed drill bit will sometimes unscrew a
screw while it is drilling off the head, but that didnt' happen to
either of these. But it did do enough that I got the cover of the lawn
mower off.
**This is the closest to what I have that they are selling now
http://www.harborfreight.com/116-in-...ill-69947.html
No reference to a minimum speed. No reference to SDS either, but it
is called a hammer drill, not just an impact drill. 3 of the 11 hammer
drills are labeled SDS. Not only are two $80 and one #120, but they
don't have the same shape as mine, which is shaped like a rotary-only
drill. Here they a Even the url says SDS.
http://www.harborfreight.com/73-amp-...mer-69276.html
http://www.harborfreight.com/10-amp-...mer-69274.html
Both are variable speed, even though only one has it in the URL.
I would never have spent $80, or even what they charge if it goes on
sale, so at least I have a spare drill for not much money. With this
extra information, maybe I can find out why my drill didn't work right.
Used cheap masonry bits that broke?