cordless drill/screw driver for weekend DIY

[gychang]

I am a newbie and confused about impact driver, drill, screw driver etc.

Interested in mainly drill and screw driver work on weekend basis, will be putting on shelfs and build desk (with my new sliding miter saw).

Is the 14.4volt system ideal for me?

gychang

[bigstick509]

Impact Driver

In my opinion you can't go wrong with the Ryobi 18V impact driver.

[mpc]

Impact driver: ever see a car mechanic using an air compressor powered impact wrench to (noisily) undo tight bolts, wheel lug nuts, etc? The battery "impact drivers" are small versions of those tools. Rather than using a small motor to turn the tool tip (like a regular drill) they use a mechanical "hammer" system. The motor "winds up" the hammers inside the unit; when they reach a certain point they're released and they "smack" into something that causes a sharp turning torque at the tool tip. The "impluse" energy is much higher than the continuous motor torque so these tools are great for driving (or removing) screws, lag bolts, etc. Way more torque/power in your hand than you expect from the size of the tool. My 14.4volt Makita impact driver can undo lug nuts on small cars! If you've ever used a battery operated drill to drive screws you won't believe the difference an impact driver makes - more power and much more control.

Battery drill: just that - a drill. For most home jobs they work fine. Higher voltages generally can drive larger bits for longer times (e.g. spade bits) but any brand name will handle most jobs. Dad used a Makita 9.6volt unit for years; that thing had amazing power because of the gearing - it had a two speed transmission. High speed for drilling, low speed for screw driving. The modern units (basically anything OTHER than ni-cad batteries) are even better than that old Makita. Mine is a 14.4 volt Makita because I got a great deal on a combo drill + impact driver package; they handle anything I throw at them. Things to watch for in a drill: the chuck size. Basically this is the max diamter of the bit you can clamp into the drill; half inch is an upgrade from basic drills and is worthwhile now if you can afford it.

Small hand-held battery screwdriver: umm... be careful here. There's far more difference in quality and usefullness in these tools than in the other battery tools. I got a freebie (job award) unit that just sucks, yet a small Black & Decker one (small tube-shaped battery that slides in/out of the back end, has adjustable max torque at the tip) works amazingly well. Usually these things have low voltage batteries so they rely on gearing to make torque... ergo they spin slow compared to a drill or impact driver. For driving screws that's good; for removing them it's annoyingly slow sometimes. I rarely reach for this tool anymore; the impact driver works far faster and better.

One thing you didn't ask about but I'll throw in there: Impact Drill. These are designed for heavy-duty jobs, typically pounding through masonry or bricks. In addition to spinning the bit, they actually move it in/out and hammer the bit's tip into the material to help bust it up. Not exactly a fine woodworking too. On many units you can turn the "hammer" or impact function off; then it becomes a regular drill. Just an expensive but powerful one.

When driving regular screws with a drill you'll find that if you don't keep enough pressure on the screw the bit will hop out of the screw head and then the drill RPMs will skyrocket... you'll grind away the screw slots! It's very easy to do. Impact drivers though don't turn continuously - they turn in short segments... so if it pops out of the screw slots it'll jump right back in pretty much on it's own - especially phillips heads. That's what I meant about more control.

If you get a combo kit with a battery drill and battery impact driver you'll be set for many around-the-house jobs. Those tools will serve you well for future woodworking too.

mpc

[gychang]

thanks MPC for such a thoughtful and complete explanation, it answers all my questions and now will get ready to spend more $$.

gychang

Impact driver: ever see a car mechanic using an air compressor powered impact wrench to (noisily) undo tight bolts, wheel lug nuts, etc? The battery "impact drivers" are small versions of those tools. Rather than using a small motor to turn the tool tip (like a regular drill) they use a mechanical "hammer" system. The motor "winds up" the hammers inside the unit; when they reach a certain point they're released and they "smack" into something that causes a sharp turning torque at the tool tip. The "impluse" energy is much higher than the continuous motor torque so My 14.4volt Makita impact driver can undo lug nuts on small cars! If you've ever used a battery operated drill to drive screws you won't believe the difference an impact driver makes - more power and much more control.

If you get a combo kit with a battery drill and battery impact driver you'll be set for many around-the-house jobs. Those tools will serve you well for future woodworking too.

mpc