Ideal pressure for decent impact

[dlundblad]

I have an Aircat 1150, which theoretically has just under 1300 ft lbs of reverse torque and can operate with a regulated pressure of 90-120 psi. It's been a decent gun for my heavy DIY use, but has wanted nothing to do with some suspension bolts as well as a CV shaft bolt torqued to 130 ft lbs. The breaker bar and cheater pipe (if it comes to it) has to come out. Rusty bolts break, I pull something in my shoulder etc.

What should I have the compressor set to in order to utilize it's full potential? An equal in strength battery powered impact is tempting, but with HF prices, I might as well spend ~$100 more and get a nice air compressor.

* I'll check the current compressor's cubic feet per minute tonight.

 

[racin4ds]

Most guns tell you exactly what PSI they are rated at (most are 90psi that I've used) I usually regulate the air in my shop to 90-95psi and it runs everything I use just fine. If you don't have enough compressor then that might be why your big gun isn't performing. You'll want at least 12-15cfm and min 1/2" ID hose and fittings to run the bigger impacts. I noticed a huge change in even my smaller impact guns by going to full 1/2" line and industrial full flow 1/2" fittings.

 

[JC1]

What size is your compressor? It will need lots of air to work properly.

I have a 27 gallon and sometimes I need to wait until the compressor stops refilling to hit the big bolts on shocks and suspension.

I'd love a 60 gallon but I don't do enough work to justify it at this time.

 

[tig1]

90

 

[Trav]

Aircat allows 120 PSI with the 1150, use a min of 3/8 ID hose and Milton V high flow fittings on every part.
3/8 hose is fine for this and similar size guns, for the 3/4 and inch guns I use larger hose and fittings.

As these tools do not usually run a full duty cycle 6 cfm will work ok, that is 25% or 15 second duty cycle. Tools that use full duty cycle would things like DA sanders, air buffers, die grinders, etc.
To determine the true cfm requirement of the published cfm multiply by 4. An example would be a DA with 4 cfm consumption in the product description (unless it says otherwise like full duty) needs 16 cfm to run continuously.
Most 60 gallon single stage wont manage that, max for them is around 13 cfm.

 

[dlundblad]

Originally Posted By: Trav
Aircat allows 120 PSI with the 1150, use a min of 3/8 ID hose and Milton V high flow fittings on every part.
3/8 hose is fine for this and similar size guns, for the 3/4 and inch guns I use larger hose and fittings.

As these tools do not usually run a full duty cycle 6 cfm will work ok, that is 25% or 15 second duty cycle. Tools that use full duty cycle would things like DA sanders, air buffers, die grinders, etc.
To determine the true cfm requirement of the published cfm multiply by 4. An example would be a DA with 4 cfm consumption in the product description (unless it says otherwise like full duty) needs 16 cfm to run continuously.
Most 60 gallon single stage wont manage that, max for them is around 13 cfm.


Dang, something like this almost seems too small then. (5.9 CFM)
https://www.harborfreight.com/29-gal-2-hp-150-psi-cast-iron-vertical-air-compressor-61489.html



Aircat's published consumption is 8 CFM. I really hope this is full duty cycle and not just 15 seconds. 32 CFM being required is high.
http://aircat.com/1-2-impact-wrench-520

 

[JMJNet]

What type of hose fittings are you using?
If you use the S-type, that is not too good.
As suggested above use the V-Style fitting.
You can see the difference when you compare them side by side.

 

[Trav]

From what iI read it is 4.3 cfm under load so about 17 cfm continuous. Its rare you would ever use it at full duty. 15 seconds on a bolt is a long time. that compressor will run it.
As I said use Milton V high flow fittings on it and the hose.

 

[Donald]

1/2" hose and good couplers.

 

[CT8]

Lots of cfm and psi from the compressor. Fast and hitting hard.

 

[Chris142]

At least 90 psi and lots of air flow.

 

[demarpaint]

I set the air for my 1150 between 90 and 100 psi. I haven't come across a fastener yet that it couldn't break loose. I run 3/8" hose and Milton V fittings as per Trav's recommendation. I keep the hose as short as possible to do the job, 25' gets me to any point in my garage w/o issue. I have a 60 gallon compressor.

 

[Trav]

The gun has its own built in restriction in the form of a 1/4" NPT fitting. For longer hoses 1/2" may make an improvement but not 25 foot.
Bigger air guns have 3/8 or 1/2" NPT fittings so you need a large diameter hose to feed them but a big hose is a PITA to work with on other tools.

 

[Rand]

you dont really need a new compressor you need 3/8"(25ft) or 1/2"(50ft+) id hose with all high flow fittings from compressor to gun.. and turn it up to about 120 because with the air flow differential it will only be 90 at the gun when running.

A compressor that is 150/165psi vs 125psi would also help.

unless you have 220v where you are working

I'd get something such as
https://www.harborfreight.com/air-tools/...ssor-61489.html

for the best compressor upgrade at a decent price.

its way way better than the oil-less 200$ models.

and you wont be getting much better on a 115v outlet.

The high flow air fittings themselves will literally double your air flow.. start there. as well as turning the air up to around 120.

 

[clinebarger]

Break the CV Axle nuts loose with a breaker bar before you raise the vehicle. What they get torqued to has NOTHING to do with breaking them loose.

For rusty bolts/nuts.....Call Victor!

 

[Trav]

I have Harris on speed dial.

 

[dlundblad]

I used it today for my rusty control arm bolts. Took them right off.

 

[demarpaint]

Originally Posted By: Trav
The gun has its own built in restriction in the form of a 1/4" NPT fitting. For longer hoses 1/2" may make an improvement but not 25 foot.
Bigger air guns have 3/8 or 1/2" NPT fittings so you need a large diameter hose to feed them but a big hose is a PITA to work with on other tools.


I got it now, thanks. For me running with 50' of hose in the garage is a PITA. What I seem to to be missing is I noticed I can turn my regulator down a small amount with the shorter hose. On occasion I need 75' of hose to get me to the front of my van if it is under the carport. Then I have to turn the pressure regulator up a bit to get the 90 psi to the tool when I have a 25' and 50' hose spliced to get me the 75' I need.

 

[bmwpowere36m3]

Usually shoot for 90 psi when the impact is running... which might been a static line pressure of > 100 psi.