Impact Driver or Wrench for large-ish hex head screws & bolts?

[MeUseDinoBone2Hammer]

Which tool is right for the job? On the one hand these hex head screws/bolts need "driving" but they also need driving via a socket (considerable length difference between a 3/8" stubby Impact + socket vs a compact impact driver with hex-to-3/8" bit + socket on the end). Additionally, fastening bolts vs driving screws offers a difference in resistance to the work. Are impact wrenches really mostly ideal for bolts on machinery and not so much for putting a hex head screw into some thick wood?

 

[KnurledNut]

Wrench

 

[RTM]

Lag screws are soft, and will tear the head off easily with an impact driver. I use one to remove them sometimes, and recently sheared it midway down the shoulder, on the way out

I know guys love driving deck screws etc, but be cautious w lags and impacts.

 

[Shiftless]

I used my M12 impact driver to sink half inch lag screws through 2x12s into 4x4 posts. But I first drilled pilot holes and passage holes. Maybe I’m just old school but I think that’s the proper way to proceed with lag screws. Some modern structural screws don’t need pre drilling.

 

[WWheeler]

I've driven tens of thousands if not more than a million lag bolts and screws in wood with my Dewalt 1/4 impact driver. If it's a large screw or lag bolt I've learned to pre-drill a pilot hole, especially if going into pressure treated lumber.

 

[619DioFan]

Normally when driving fasteners into wood ( or removing them ) I use a Ryobi hex driver with appropriate impact rated adapter and socket ( or bit ) I do pre-drill for lags. on rare occasions when the fastener is larger I will use the bigger impact gun.

 

[Xcursion88]

Fastenmaster HeadLOK fasteners are fantastic.

More expensive? Indeed. Worth it? Absolutely.

No drilling. Put the supplied bit in your impact driver and run those s.o.b's in there.

Stronger than lags, code approved

 

[mike93lx]

I use my high torque Dewalt 1/2" to drive large lags, particularly stuff like 5-8" fasten master headloks/ledgerloks. It is so much faster than a 1/4" driver and I have never had a problem with stripping or damage.

I had a project last year that used something like 80 7" screws. The 1/2" saved a material amount of time and probably also saved my driver from a release of the magic smoke

 

[anndel]

I used my M12 impact driver to sink half inch lag screws through 2x12s into 4x4 posts. But I first drilled pilot holes and passage holes. Maybe I’m just old school but I think that’s the proper way to proceed with lag screws. Some modern structural screws don’t need pre drilling.

This

 

[KnurledNut]

Which tool is right for the job? On the one hand these hex head screws/bolts need "driving" but they also need driving via a socket (considerable length difference between a 3/8" stubby Impact + socket vs a compact impact driver with hex-to-3/8" bit + socket on the end). Additionally, fastening bolts vs driving screws offers a difference in resistance to the work. Are impact wrenches really mostly ideal for bolts on machinery and not so much for putting a hex head screw into some thick wood?

There is some confusion here.
Define "large-ish".
Can you be a little more specific on application?

By stating "hex head screws and bolts" I dismissed small diameter structural construction screws like GRK RSS, FM LOK, SST, Spax, PowerPro, Tapcon, etc.
Any modern impact driver will do just fine on those, but often a drill works better and faster without all the noise.

To me "Large-ish" implies:
Installing 10" 1/2 zinc lag screws (3/4 hex) which is gonna kill an impact driver.
Installing 7/16 hex garage door screws can even be tough on an impact driver.
1/2" Powers Wedgebolts (3/4 hex)? Good luck with your impact driver.
If were talking exterior cladding screws of the 1/4, 5/16, 3/8 hex variety, then yeah, am impact driver is great. (I wont get into Versa-clutch.)

Lots of variables here. We need more details.
In a nutshell, impact wrenches certainly serve a purpose in construction, especially heavy.

 

[Zewnten]

Assuming the OP is referring to lag screws, pre drill a hole the size of the lag's shank, as it pulls itself in the wood compresses and binds. Also don't buy garbage lags and they won't break as easy.