Tell me about impact guns

[Drew20]

I need to replace a wheel bearing on my modern Nissan, and having looked on YouTube, I think having an impact gun will make the hub nut a much easier proposition. I've only ever used hand tools on my cars, so this is a new thing for me.
Should I get an air gun, or a battery gun? I'm looking for 2nd hand quality tools, but on eBay the snap on battery guns are still quite a price, even when they're clearly toast! The air guns are much cheaper, but not quite as convenient I guess, as I'd need to hook up a compressor. I have a basic garage compressor, I'm assuming that this would be enough to power an air gun.
I'm also assuming that when refitting the hub nut, I'd need to torque it by hand, i.e. I can't accurately use an impact gun (air or battery) to torque the hub nut (I saw a YouTube garage vid do this, but how can they know what the final torque is?)

Thanks

 

[Gransin]

I bought a Hazet 9012mt air gun about two years ago, and due to the small size and big power, it gets used for most jobs/maintenance that I do since you can actually get to those bolts in relatively tight spaces.
I don't have a serious compressor either, but it's okay for shorter bursts which usually gets the job done.

I order most of my tools from TBS Aachen in Germany due to the lower price for quality tools, and that's where I bought the 9012mt as well:

Hazet 9012MT Schlagschrauber 1/2" 1400 Nm

Hazet 9012MT Schlagschrauber 1/2" 1400 NmHazet 9012MT Schlagschauber 1/2" 1400 Nm Der Profi Druckluft-Schlagschraube...

www.tbs-aachen.de

My dad has the even smaller version, it's been in hard use and he's really happy with that one as well:

Hazet 9012M-1 Schlagschrauber 1/2" extra kurz

Hazet 9012M-1 Schlagschrauber 1/2" extra kurzHazet 9012M 1/2" Schlagschrauber, extra kurz Merkmale: Abluftf&uu...

www.tbs-aachen.de

There's nice electric ones out there as well, I haven't used them much, so I can't speak for them.

The hub nut needs to be torqued by hand, here's a great write up:

Wheel bearing 101

EDIT: realized it was for your new Nissan and not your coupe, and I don't know what kind of bearings Nissan uses up front?

 

[Krzysztof]

Hi,

Topic is probably too big for topic.

I found impact gun (both: air or electric) extremely handy.
Newest battery (LiON) operated guns are much more handy than for air. I can even risk to say they are more powerful (especially comparing hoppy-level tools).
My friend has 230VAC tool and it is perfect in his eyes for changing wheels etc.

During the assembly proper tightening torgue (especially for hubs and bearings) is crucial.
Modern, professional electronic tools have the ability to setup the torque limit. Most of factories using them currently.
Even simpler models have some limiters which are very helpful. I used it even during dissassembly to protect bolts/nuts against braking as on full power it is just a matter of seconds.

There so many options here on the market but for sure it is someting good to have when doing with cars (even from time to time).

 

[Dick Steinkamp]

If it is just a one time need, how about borrowing or renting an impact wrench or buying a long breaker bar

 

[Markos]

Unless you plan to use other air tools, I would buy an electric gun. They work very well, don’t require a compressor, and overall aren’t as loud.

Impact guns are helpful for breaking nuts such as those on the lugs, or removing nuts on a shaft that rotate. This includes the steering box, and struts. You can use the gun to gently get nuts going, but you want to tighten with a torque wrench. Some people conflate impact wrench and torque wrench. A torque wrench measures the torque of the fastener, telling you when to stop.

Me using spring compressors and an impact wrench on a strut shaft that rotates. It is difficult to understand how much easier this is unless you’ve done this with hand tools.

 

[halboyles]

Cordless impact guns are indispensible for this kind of work. I do about 75% of BMW work with a set of 18v Makita impact guns in 1/2 and 3/8" sizes. You'll also need some impact sockets. They are cheap at HF and, if they break, they'll give you another. The Makitas aren't cheap, but neither is your time. You will waste a lot of time with a cheap impact gun. Watch for sales on eBay of refurbished Makita products.

 

[Krzysztof]

Makita, Milwaukee, DeWalt etc.

Most of them are all good. I'm really satisfied with the second brand. Great quality and long lasting batteries.

Good to stay at one brand. Maybe you already have some drill or other tool so it's to be considered to collect the same system tools (less chargers ;-) )

 

[halboyles]

Good to stay at one brand. Maybe you already have some drill or other tool so it's to be considered to collect the same system tools (less chargers ;-) )

[/QUOTE]
As your cordless collection grows, you will definitely appreciate this sage advice! I now have a huge assortment of Makita power tools including leaf blowers to clean out the garage, a portable vacuum for the lathe and drill press, portable LED lights, and even a portable fan for working on interiors in the heat. I even used a portable Makita sawzall to rip out our kitchen and remodel it. All good fun!

 

[Drew20]

That makes sense. I have a battery drill that I use infrequently, and so I never have a charged battery to hand when I need one! An impact driver would also be used rarely, so a battery driver would need a charger that can keep a battery in good shape and charged.
I had not considered a mains powered one, will look into this

Thanks all for your considered input

 

[bavbob]

I bought one from Harbor freight, electric, been happy with it. I abandoned battery powered anything since I am a weekend guy and I never have a battery charged when I need it. I will say my kids bought me this : 1/2" Hand Impact Tool - Lisle 30000 and it has really been helpful.

 

[Stevehose]

I have a plug in electric impact wrench from Lowe's and it kicks butt

 

[Nicad]

I love having a compressor. You can run cut off wheels, die grinders, washing tools, bead blasters, home powder coaters. About the best cheap tool I have is a pencil grinder. Amazing little tool. Another would be a needle scaler.

 

[Simufly]

Great tool. I have both a 18volt battery one for most jobs and a big airtool for the bigger jobs.
Two caveats IMO:
1. impact sockets are a MUST.
2. Use for undoing ONLY

 

[Drew20]

I bought one from Harbor freight, electric, been happy with it. I abandoned battery powered anything since I am a weekend guy and I never have a battery charged when I need it. I will say my kids bought me this : 1/2" Hand Impact Tool - Lisle 30000 and it has really been helpful.

I have one of these hand impact drivers, but hadn't equated this with an impact gun, oops. I find the hand impact driver invaluable for those little brake disc screws! Happy to give my hub hearing a go with it, see what it can do.
...as the air gun I've bought is not up to the job!!
Actually, I suspect the air gun is fine, but my compressor is just not man enough to supply enough air.
I bought this SIP gun lightly used from eBay, and it will whizz a wheel nut off, but only just. I've had to use a very short air line, and my compressor can only run it for a few seconds, so it's not the convenient option I'd hoped for...
It is spec'd to run at 90psi, and my compressor does 110, but quickly falls off to 70-80 as the receiver is not large.

Think I will try a corded electric gun next. There's a Draper gun rated at 480Nm

 

[Krzysztof]

For small screw holding the brake dics big wrench will not help as long it has no reduction in pressure or torque.

Good is to start with some anti-rust spray and hit the bit into the bolt. Sometimes also a gas torch. In most cases it is enough.
Buying specific air spring gun (I think I know what you meant) might be an overkill as it will not be used too much.

Even if the screw will still hold on, you can drill it and quite often threaded part will unscrew after easily. CCW drill are also a good tool (much cheaper than air guns).

Hope it will help to get a rid of nasty bolt!