What about tools?

34 responses total.

I watched some workmen framing a small building using 2" (nom) lumber,
with screws instead of nails. It was fast and a lot quieter than nailing.
They used what looked like an electric drill, but it also looked like
they set the screw into something that held it while starting it. I was
also a little surprised the screws went through 2" lumber so easily.

What is the tool used for this, and how is the nail held? Does a pilot
hole have to be drilled first (I now don't rcall about that)?

For pine probably no pilot holes are needed.  

Sounds like the sort of drill/driver used by drywall hangers.  Usually pretty
powerful at low speeds and equipped with a clutch for faster start/stop.

I find a "drywall hanger" drill/driver in the Craftsman catalog. (My
need is to install risers from below on basement stairs that have only
treads. The space is rather cramped for nailing, and I also thought
it would be better to use screws through the treads down into the risers.)

You might also just use a powerful variable speed drill.  The screw bits will
fit drill chuck, and you can buy the magnetic holder.  Even without fine speed
control at the low speeds it's not hard to do (takes some practice, though).

What I have is a 0.25 HP single speed drill (Rockwell). I guess that
won't work. Magnetic holder? That's news. And, what kind of screws
are used for framing? What I saw them using were black (and long). 

Jim has an electric screw gun of some sort that you could probably borrow.
Or maybe it is a drill with an attachment.  We used it to put up all the
concrete board siding.  It stops at a certain depth.  

I am just seeking information on the tool(s), accessories, techniques and
experiences, for now. Makes and models would also be of interest. 

I have a Makita 6095D cordless electric drill that I use a LOT for stuff like
this.  It's "only" a 9.6 volt drill but all the volts stuff is mostly just
hype when it comes to portable tools.  (Volts is not a measure of power.  Nor
is amps.  The product of the two is, however.  It's called watts.  Heck, a
120 volt analog electric clock has a 120 volt motor in it.  Just because it's
a 120 volt motor doesn't mean that a clock motor would be a good choice for
a portable impact wrench for tightening the lug nuts on the truck. ;-)

I got this drill because I had gotten its brother years ago as a gift.  It
was a not variable speed but has a torque limiting clutch that you can set.
My wife and I were constantly going for it while we were building our house
and often needed it at the same time.  I got the 6095D because it took took
the same batteries, was variable speed and had a keyless chuck.  I got the
drill, without batteries and charger, on sale for $65.  At the time the set,
with two batteries and charger, was going for $109.  I have used it for
exactly the purpose you describe, Rane.  It will drive, or break, any screw
I dare drive with it in low gear. If you get such a drill set, look to spend
at least $100 for the tool, two batteries and a charger.  Anything above that
price range should be capable of doing.  Variable speed is a very handy
feature as is the torque limiting clutch, two speed transmission and the
ketless chuck.  (If you look closely at and play with the keyless chucks of
cheap and expensive drills, you will notice that the good chucks seem to have
ball bearings in them.  These are worth the extra price because they grip
better and are easier to loosen and tighten.  Good, keyed, chucks are best
if you need lots of gripping power like for drilling 3/8" holes in metal. 
You will find that modern deck / drywall / utility screw heads fit the P2 and
P3 philips bits so well that you don't need magnets.  I have a selection of
P2 bits of various lengths to accommodate screwing in tight paces or at the
bottom of deep holes.  Stadium Hardware has a good selection.  Home Depot
would be a good place to look at drill motors.  Of course you don't need to
go cordless.  Variable speed corded drill motor works well too.  You don't
even need the clutch if it's variable speed as you have better control over
how deep the screw gets set.  If you do get a corded drill, stay away from
the 2,000 RPM cheap ones.  For driving things you need torque.  Spend the
extra $'s and get on with a few more gears in its gearbox.  You want something
with a top RPM of about 1,000.

If you want a nice, tight, joint drill a clearance through the first board.
Otherwise there is no need to drill holes other than to prevent splitting in
very dry or thin wood.  The screws these days are so sharp that they zip right
in.

Jim has three different things that you can borrow.  He says a clutch is handy
unless you like breaking screws.  He has two angled drills, one with a screw
clutch and the other fits into smaller spaces due to its shorter head.  Not
cordless (you don't need cordless for working where there is power).  About
$120 for a Sioux and $100 for a Milwaukee (without the clutch, also made by
Sioux).  He also has a 'drywall gun' by Milwaukee, the higher amp one, over
$100.  For putting up cement board siding he used them all and none were
perfect.  You predrill the first piece when you want to pull two pieces
together so it sucks the boards together.  But then the head sinks deeper.

The clutch is nice in theory but I find that there is too much variability
in your average chunk of wood to make it truly practical.  With a given
torque setting, I sometimes find the screw not going in as deep as I would
like because it hit a knot or going too deep other times because I hit a
soft spot.  Drywall guns and deck guns drive the screw until a given depth
is reached.  I set my clutch such that I don't snap off the screw should I
hit something really hard when I'm not paying close attention.

I think the one time I used a drill with a clutch I wasn't very happy with
it.  With a variable speed drill it's easy enough to feel how the screw is
driving and when you should stop.  Even back in the speaker company days with
a temperamental old Sears drill it wasn't very hard.

Jim would use the clutch and then sometimes finish off the job with a hand
screwdriver.

I looked up various drill/drivers on the web. Klaus' Makita 6095D
has a 2-speed transmission for 400/1100 rpm. All the drywall screw
drivers have variable/reversible speed but top speed os ca. 4,000 rpm.
(Why so high just for driving screws?) There is no corded version
of the Makita 6095D - nor do other makes have most of its features. 
This gets tricky....

Places like Home depot have a lot of drills on display.  Lots of models too.
Drywall screws only get driven about 3/4 inch deep and the motors are usually
line powered and are fairly powerful, making low RPM's unnecessary.  High
RPM's make driving screws much faster.  The guys getting payed by the square
foot of sheetrock hung don't want to be messing around with 400 RPM drills.

And it is usually into new wood, not aged wood that has turned to concrete.

You may also want to take a look at DeWalt drills, Rane.  The heating
contractor that helped me out was supplied with those.  Milwaukee is another
really nice brand.  Milwaukee has a reputation for building tools with plenty
of power in them.  I found it interesting that the heating contractor got
reconditioned drills from DeWalt to save money.  They seldom bought new.

Sears (Craftsman) seems to have a corded drill with features like your
Makita. 

Any 1/2" chuck drill of decent quality ought to be powerful enough for any
screw work.  That's what I've got, a neat Skil drill with high torque and a
hammer drill setting.

I had a commercial duty, 3/8", VSR, K-Mart drill that would drive screws with
no problem. (Made by Black & Decker who also makes DeWalt)  It needed a lot
of fixing but that's because I used it hard.  It finally burnt out a couple
of years ago while I was building the house.  I'd had it for some 30 years.

You will find that a drill that is geared down a lot is more controllable at
low speeds.  I'm not a big fan of Craftsman power tools but they are usually
just fine for the occasional user.

I have finally looked at a wide range of drills, and discovered that
many battery-powered drills have clutches, but none of the corded
drills do (in the group I saw). Why is that - to limit battery current?
The advantage of a clutch cited above was to prevent twisting off
screws, but surely that would be an advantage on a corded drill too. 

You didn't look at the BIG hammer drills, capable of running a 1 1/2" carbide
bit through concrete and twisting your arm off should it get jammed.  (Been
there, done that :-)

I don't know why they don't put clutches on corded drills.  To keep the price
down?  They are not usually used to drive screws the way battery drills are?
Beats me.

Good point - screw drives would be used the most in construction when
building houses, when they don't usually have AC power. I see lots of
advantages in using driven screws in place of nails in all sorts of small
woodwork projects (won't dent wood when you miss... 8^}), but then one
has/wants more control over the use. 

Now, the followup question: what are recommendations for the sizes of
screws to use with power screwdrivers? I'm familiar with hand screwdriving,
and selection of screws for that, but what additional considerations
apply to screws used with power drivers? For example, I can hardly ever
twist off a screw head by hand, but it might be easy with power, so should
larger sizes be used? What would be used for screwing deck boards, or
framing, for example? I would expect that the screw should also penetrate
the 'bottom' board at least 1.5X to 2X the thickness of the 'top' board,
with a minimum of ca. 4X the screw size (diam). Any other rules-of-thumb?

Jim wants a minimum of 3/4" into the supporting member (the second board) if
it is a 1" or 2" board, so that it will hold.  The thinner the screw the less
chance of splitting something.  The only choices are 6 or 8 in a bugle head,
which tends to bury itself into the wood.  Jim uses 6 where possible, and 8
only if the 6 did not hold - he replaces it with a larger screw.

For screwing stairs together, I'd go for about 1 1/2 inch penetration into
the supporting member if it's pine, less if it's hardwood or plywood.  If
you're securing a 2X, I'd go with a #8 or larger.  You can twist off a #6
bugle head screw by hand, at least I've done it more than once.  #6 is
fine for light duty fastening:  Drywall, panelling, 1/2" sheets of plywood
to framing, etc.  Construction adhesive is also useful stuff.  Go with
Tighbond.  I've not been very happy with some of the Liquid Nails
products.

I chose a Craftsman 27112 1/2" corded variable speed and reversible, 850
rpm (max), with auxillary side handle and keyless chuck. It says it has
electronic feedback to maintain speed under load. I will be using No. 10
2-1/2" screws for my stair job. 

The question of why portable DC drills have clutches and corded AC drills
do not still intrigues me. I suspect this is because they use univeral
(series-wound) motors. A DC series wound motor has essentially no current
limitation when heavily loaded, which could burn it out: a clutch limits
the current by limiting the torque. A AC series wound motor, however, has
automatic current limiting because of the reluctance of the windings.  (I
once knew more about these characteristics, but have forgotten most of
it.) 

Jim's AC drill has a clutch.  Sioux.  They make drills for Milwaukee.
He has a Milwaukee without a clutch.

(hmmmm...a fact negating a theory...)

I have a cordless drill where the cluch can be taken out for drilling.

Re #26: after trying out my new drill, and reading the manual, in that
order, I found it has a little maximum speed knob, by which one can adjust
the top unloaded speed from 850 rpm and down. Variable speed is still
attained by the trigger position. The variable speed also occurs in small
increments, not trully continuously. Do all variable speed drills have
these features (variable max speed and incremental speed)? 

After a little more study, I believe that the AC motors are "repulsion
motors", not series-wound motors. AC repulsion motors also have the
property of current (torque) limitation at high loads without using a
clutch. A clutch could, however, give more direct control over maximum
torque than does a motor characteristic. 

I'd guess that the max speed knob just shifts the transmission.  Many battery
drills have this capability.  Both of mine do.

Repulsion motors?  Okay.  The AC power tools I've taken apart seem to be
series wound.  I could be wrong as I never really looked with that in
mind.  I will the next time the opportunity presents itself.

A "repulsion motor" applies the AC to the stator, and "shorts" the
rotor with brushes placed at a displaced phase from the stator. There
would not be a direct electric connection between the stator and rotor
windings - easy to check (with some disassembly). 

The max-speed knob on this drill is on the trigger switch, and is very
tiny. The effect seems to be electric, not mechanical. Since this
drill claims to have an "feedback" system to maintain speed, I presume
that the little max-speed knob does something electronically.

Does the repulsion motor require a capacitor to achieve the phase shift?

Some do, but usually the phase shift is obtained by the brush position on
the commutator. If the brush position is 15 to 20 electrical degrees
either side of the magnetic field center, speed varies inversely as the
load. Placing a *second* set of brushes at 90 electrical degrees from the
first set will maintain constant speed. Speed control can be obtained by
shifting the brushes around the commutator. My sources that describe
these motors do not also give speed-torque curves, which would be
most instructive. There is only one set of brushes visible on my new
drill, but one cannot determine their electrical orientation, as that
depends on how the stator and armature are wound. 

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