I am in the process of installing a handrail down to my basement. I need to
attach two of the rail mounts to a cement wall. I spent a few hours trying
to drill into the cement--- very slow. I am using a 7/16th drill bit from
TrueValue-- it is new and I haven't turned the tip "blue." I got one set of
holes done (I need to go in about 1 1/2", but it took forever. Are there
better drill bits out there that might speed the job? I have a conventional
corded drill, not a hammer drill.
If the masonry drill bit is ok, the concrete normal (poured concrete
foundation wall, 40 years old), and the drill spinning correctly---- could
the presence of stones (aggregate) in the cement be a problem? Can a
masonry drill deal with stones? Thanks for your help.
I have never had any success with masonry bits in a standard drill (and I have
tried the expensive bits). As soon as the bit hits a piece of aggregate nothing
happens except that the bit is destroyed. Rent, buy, or borrow a hammer drill
You can mannually peck with a conventional drill. Just tap it in and out
of the hole. It sucks compared to a real hammer drill, but it's better
than just using the regular drill if that's all you got.
But get a hammer drill: they're not that expensive and they work much much
Remove the dead poet to e-mail, tho CC'd posts are unwelcome.
Ask me about joining the NRA.
Why dont you get one of those tools that uses a 22cal shell to shoot a
fastner. They shoot nails and (I believe) a nail sort of thing with a
threaded end to put a nut on, like a stud (correct me if I am wrong, I
have only shot nails in the past). These things do the job. I have
fired them thru all sorts of stuff.
You could probably fasten tbe railing with JB Weld too, if you have a
way to hold the rail in place till it dries. JB Weld holds on anything
except those exposed to very hi temps like an enhaust manifold.
Of course a redneck would use duct tape :)
Yes I tried all the modern technology, star drills, carbide drills, hardened
drills pilot holes,
and altogether $20+ worth of crap and no, you cannot drill treough concrete
with aggregrate. think of it as a sunk cost. start fresh. the .22 gun
When drilling concrete without a hammer drill, I find a star drill and
hammer work better than any type of bit in a regular drill. The ancient
method works pretty damn well!
I wonder if anyone having problems with a star drill was like the guy I
saw. He put the star drill into his electric drill! The damn thing got
hot and lost it's temper! I wonder why? ;-)
This is good to know...you should publish your findings immediately.
The concrete industry simply *must* stop putting aggregate in their
concrete mix, nevermind that it is a defining element of "concrete".
And of course all the fools that have been drilling holes in concrete
must stop doing so!
(wonder if he hit a piece of rebar...)
dadiOH's dandies v3.05...
...a help file of info about MP3s, recording from
LP/cassette and tips & tricks on this and that.
Get it at http://mysite.verizon.net/xico
I use a regular variable speed drill on older concrete and standard masonry
bits work - slow on the rpm's, not bad for 3/16 & 1/4. Too fast just
heats/blues/polishes the edges of the cutters and if you don't keep it
straight it rounds the tips all that much faster. Masonry `Carbide Tipped
Bit` is designed to hammer & chip a hole, not really cut like a regular
Diamond tipped bits drill quick & work easily,,, hammer drill will bust em
quik too .
Don't worry too much about bit speed, Just brace yourself and put as
much pressure as you can on the back of the drill motor. Try to keep the
motor just above bogging down with forward pressure. You can also try
drilling a pilot hole first maybe a 3/16
I appreciate all the input. Sounds like I need to fined a hammer drill with
an appropriate masonry drill bit (yes I was using a masonry bit before).
Typical "simple" project evolves into weekend project.
Thanks to all.
I should have said this too. I tend to drill a smaller hole first,
then enlarge it. I'd use a 1/4" first, go to a 3/8" and finally the
7/16". Yes, a hammer drill would get the job done a lot faster. If
you forsee doing this again, you might be able to buy a hammer drill
for twice what it costs to rent, but then it's yours. Just dont buy a
real cheapie. I had a cheap Skil and it didn't do shit. THe "hammer
effect" was more of a vibration, and was near useless. I completed
the job with my extra heavy duty Milwaukee brand Industrial drill (non
hammer drill), and it worked like a dream. Hammer drills require a
special bit too. They are usually black in color.
Only a couple of things I can suggest:
Get a hammer drill, or rent one.
Make sure you don't keep spinning the drill when you feel it stop going in.
This will "smoke" the bit, turning it blue. That is a sign of overheating.
Keep the rpms up, but not high when you feel it stop penetrating. You can
also spray some water into the hole.
Get a piece of cold rolled rod, or some steel that is very hard, but smaller
diameter than the hole. Sharpen it to a chisel point. When you feel the
bit hit something hard and stop penetrating, stop drilling. Put the smaller
rod in the hole, and hit it lightly with a hammer. This will help fracture
the piece of aggregate you have hit. If you don't have any cold rolled,
stainless, or an old center punch, sacrifice an old screwdriver. Cut off
the handle, as it will split. Just keep the point sharp.
A rotohammer will drill each hole in about ten seconds. A hammer drill will
do it, but not as fast.
A regular drill will do it, but you will probably burn up bits.
A powder charge will also do it, but may fracture some concrete.
If you anticipate doing any more of this kind of project, go get a hammer
drill. I have a Makita and a Metabo. They are okay, but I prefer a
Milwaukee rotohammer for serious drilling of holes larger than 3/8". Any
hammer drill will be better than a regular drill.
HTH - try the punch thing before buying a drill.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.