Air Quick Coupler - Type G made easy

[Shop-hound]

Upgraded a while ago to type G (3/8 industrial) due to the larger bore size for sandblaster, impact, and HVLP gun + future proofing. While great for minimizing pressure and flow losses, it’s a bear to change out tools with 120 psi in the line. My wife flat out can’t get the fittings out, brother in law with wrist issues has a lot of trouble. So I went searching for a fix. I did research Stedlin and am very impressed with his product, but since I have well over 30 air tools, hose etc, and still wanting to keep my large bore stuff, I found Milton safety couplers. The 5-in-1 Multis for type M/L etc have dismal reviews (understandably trying to cover so many different geometries). Type G covers only 2 variations so I bit the bullet for $40 or so each for the type G and am very impressed. The red ring pulls back to bleed the air in a quick puff, then the tool can be effortlessly decoupled (now no air pressure). Amazing difference to usability and no leaks!

Website and video link below FYI

Milton® Industrial - Safety Couplers

Milton® Industrial Universal Safety Couplers are designed to connect your air tools to a variety of air compressor hoses in your automotive shop or mechanic's garage.

www.miltonindustries.com

For any fellow type G users I would recommend, but also wanted to hear others experiences with these. I have no affiliation with Milton lol

-Trevor

 

[NFH2740]

Prevost S1; your future proofing has been unproofed.

 

[Walkers]

And also, you didn’t list any tools that require any more than 90psi. Just regulate your air pressure down to 90 and make it easier on yourself and your tools.

 

[Jswain]

90 @ the regulator + 50ft 3/8" hose = pretty weak air tools. You want 90 @ the tool, with the trigger pulled, so set the regulator to 110-125 depending on hose length/ID, the only thing seeing extra pressure will be the trigger valve when closed/idle and it won't complain a bit

 

[Stedlin]

Using G style couplers with a 3/8” hose doesn’t make sense.

At pressures over 100 PSI and flow rates under 50 CFM there is virtually no difference in pressure drop between a G type and common HiFlo couplers.

 

[Jswain]

Using G style couplers with a 3/8” hose doesn’t make sense.

At pressures over 100 PSI and flow rates under 50 CFM there is virtually no difference in pressure drop between a G type and common HiFlo couplers.

He might be using 1/2" hose for the blaster/high flow tools and wanted to keep everything the same fitting?

 

[Shop-hound]

1\2" hose and all 1\2" NPT fittings throughout. I keep the hose after regulator limited to 25' if I'm in the garage.

The original reason for my upping fitting sizes was painting my house with my HVLP gun, attached to compressor in garage with 100’ + hose and adding in air dryer, separator etc. I went as big as I could (reasonably) to try and minimize any losses.

It also helps me to come to next door neighbors rescue with the impact gun/ die grinder etc (suburb dweller .

-Trevor

 

[Shop-hound]

Couple pics to illustrate my system. Normally I just have air compressor (60 gal, 11.5 CFM at 90 psi rated - looking to upsize soon). 1/2” NPT out from tank (see ball valve/galvanized union in photo below), Runs to my air cooler (3/4” L copper tubing), then to coalesce filter, regulator (all 1/2”), G coupler, then 25’ 1/2 air hose, G coupler again to tool.



Now if I’m painting or blasting, I then tie in my air dryer (desiccant beads & after filter) using the short run of hose shown below with another G coupler. (Is quick to add in, no T tape and farting around).



Finally, Then if I’m painting/blasting far away I’ll then add in my 100’ rubber (red hose), which now has a total of 4 coupler connections in the system. This is why I was so adamant in keeping losses to minimum.



If I even gain a CFM or 5 psi it’s worth it at this length. I was barely able to keep my HVLP happy with this setup.

@Stedlin - I remain impressed and interested in your products potentially looking to make a whip hose for some of my die grinders and 3/8 impact (really dig the swivel ability. Only ones I can find in 1/2” are either a choke on air or $150…). I’m in Canada, are you folks shipping this way yet or still just Amazon option?

-Trevor

 

[GeoBruin]

Couple pics to illustrate my system. Normally I just have air compressor (60 gal, 11.5 CFM at 90 psi rated - looking to upsize soon). 1/2” NPT out from tank (see ball valve/galvanized union in photo below), Runs to my air cooler (3/4” L copper tubing), then to coalesce filter, regulator (all 1/2”), G coupler, then 25’ 1/2 air hose, G coupler again to tool.



Now if I’m painting or blasting, I then tie in my air dryer (desiccant beads & after filter) using the short run of hose shown below with another G coupler. (Is quick to add in, no T tape and farting around).



Finally, Then if I’m painting/blasting far away I’ll then add in my 100’ rubber (red hose), which now has a total of 4 coupler connections in the system. This is why I was so adamant in keeping losses to minimum.



If I even gain a CFM or 5 psi it’s worth it at this length. I was barely able to keep my HVLP happy with this setup.

@Stedlin - I remain impressed and interested in your products potentially looking to make a whip hose for some of my die grinders and 3/8 impact (really dig the swivel ability. Only ones I can find in 1/2” are either a choke on air or $150…). I’m in Canada, are you folks shipping this way yet or still just Amazon option?

-Trevor

Nice setup. Isn't it likely that it's your compressor that is responsible for the inability to keep up with your paint gun though and not what's downstream?

I ask because I have a lot more **** between my compressor outlet than you and I still see a ton of flow at the other end. Mine goes: tank outlet to 1/2" ball valve, 1/2" whip hose to coalescing filter/dessicant filter (all half inch ports) to about 30 feet of 3/4" Maxline to a short 1/2 whip hose to a ball valve to a motor guard filter (1/2" ports) to a whip hose to a hose reel with 3/8" inlet port, 50' of 3/8 hose with a Stedlin quick coupler on the end. Adjusted at the reg to get 90 psi at the end of the hose (about 100 psi at the reg) I right around 100 CFM at the end of the hose.

With what little you have between tank and your gun, I can't imagine your glow is getting restricted much at all. I also assume you spray gun takes much less than 90 psi

 

[Shop-hound]

Hi GeoBruin. I was actually reading some of your posts about your air system last night. Agreed on the compressor now being my bottleneck. At the time of my line/coupler upgrade (2+ years ago), all I had was the typical type M - 1/4” , using 50’ of 3/8” hose etc, and they were choking the system. I did some research WRT performance, durability, ability to run larger tools for future use not restricted (blaster, 3/4” impact etc) and availability, type G couplers were the choice that stood out. My air tools woke right up as did my paint gun which was exactly what I wanted, with of course the unintended consequence of the coupler being a goddam Popeye forearm exercise at tool change and full line pressure .

At this time, since I have a full type G system, and now a coupler that relieves the pressure and makes tool changes a breeze, a full switch over doesn’t make sense for my application.

That being said, reviewing @ Stedlin’s data and testimonials from other GJ users I am next looking at using his system (specifically the swivel coupler) for a whip and a couple of my Die grinders for fab work.

Nice to have options and lots of great input from members here. Appreciate it guys!

-Trevor

 

[Stedlin]

Your comments about Stedlin are appreciated.
I’m wondering about the 2 in 1 coupler you are using. It looks like a similar design to the 5 in 1.
The 5 in 1 that I got from Coilhose years ago that leaks requires a significant force to connect even though it’s depressurized. 17 pounds or more. I’m curious if the G type is even harder to connect.

 

[Shop-hound]

That’s a good question. I can say that the force required is night and day from the standard couplers. I’d be happy to measure this for the common good on here (and also very curious to measure pressure drop and flow at some point).

What type of setup are you using to measure the insertion force? I suppose a guy could press the plug/tool against a bathroom scale and watch for max value. The accuracy at the low end (ie 10-25 lbs range) might not be great. Another option would be to clamp the coupler in bench vise and add weight to top of tool until it engages.

-Trevor

 

[Stedlin]

Air tool coupler insertion force test

I’ve been using this force gauge for about 5 years. I tested a G style coupler while some Milton people were here. I couldn’t connect it myself so I had my associate try it. As I recall it measured over 60 pounds and he could barely connect it. I believe the pressure was 120 PSI.
Don’t bother testing it. I’ll probably get one and test it myself.

 

[Shop-hound]

Copy that.

And 60 lbs! Yeah it was a beast to use I can attest to that. If I was doing this in a pro environment daily that would wreak havoc on the body (still did as a weekend guy). Definitely proves the concept that there needed to be a better way!

 

[Stedlin]

http://coilhose.com/index.php/couplers-and-connectors/5-in-1-couplers/120use.html

Coilhose was selling these years before Milton picked up the line.

 

[Stedlin]

Bought one and tested it. Disassembled and examined.
My thoughts are it’s positively huge and heavy.
It does work well at least initially. Much easier to connect than the 5 in one.
It’s a huge improvement over a standard 1/2” coupler.

However, it uses a very thin flat seal with zero clearance to make the air tight seal on the plug barrel.
This is a major weak point. After just a few plug insertions it’s already showing damage,
My 2 cents.

 

[Shop-hound]

Thanks for following up on this @Stedlin . The wear and leaking is what I was worried about. Not in a production environment, but I am out there a lot!

For the whiplike and swivel, I am wondering if you have any kind of distribution in/to Canada at this time? I see Amazon, but the packages aren’t exactly what I would want and curious if buying direct as GJ member would have savings?

 

[Stedlin]

Another issue I observed is that it is not particularly optimized for flow. A simple design modification could increase the flow capacity considerably.

No Canadian distribution as yet but I am working with a friend near Montreal to set it up.

You can PM me with what you are interested in buying and I will see what I can do.

By the way, what exactly is a whiplike?

 

[Shop-hound]

Whipline . My fat finger typing.

 

[Stedlin]

I checked the flow performance of this coupler and it is very similar to a common 1/4” HiFlo such as a Parker RF series. Extremely poor for such a large coupler.
For example 6 PSI pressure drop at 90PSI in @ 50 CFM.
It should be a lot better.

 

[Shop-hound]

Oh wow… so I’m not gaining anything by having this behemoth vs a standard high flow or running a Stedlin coupler.

How does the pressure drop/flow loss look with your swivel adapter? Sending a PM now with shopping list of that Im thinking of going with

 

[Stedlin]

Oh wow… so I’m not gaining anything by having this behemoth vs a standard high flow or running a Stedlin coupler.

How does the pressure drop/flow loss look with your swivel adapter? Sending a PM now with shopping list of that Im thinking of going with

You're certainly gaining size and weight. You might or might not be gaining flow. Depends on several factors.
The pressure drop of 6 PSI at 90 PSI in and 50 CFM is equivalent to some 1/4" high flow couplers but not all. An example is a Parker RF series at 6 PSI pressure drop and a Milton ColorFit purple HiFLo and equivalent at 13 PSI pressure drop. The Stedlin QuickCoupler is also about 13 PSI. The orbital joint adds a considerable pressure drop at 50 CFM. However the IR gun you mentioned uses less than 30 CFM under load.

 

[dr_clyde]

I gotta admit, I’m kinda fascinated by this cottage industry that’s popped up around air couplings. Not something I would have known existed if not for GJ.

Every shop I’ve worked in just ran standard Milton or whatever the industrial supply sold and no one had ever complained about the couplings. Most everything was 3/8 hose and 1/4” M style or A style *******. Big stuff was hard plumbed and bypassed the coupler entirely.

When I have a mess of sandblasting to do id rent a tow behind screw compressor and that usually has cam lock couplers instead of push in ones.

Biggest problems I see in home air systems is the supply lines being too small and the hoses are too long. That and they typically choke the whole system by regulating the air right out of the compressor to 80-90 psi. The air system should have regulators at places where lower pressures are needed, not depriving the whole system for the occasional tool that needs low pressure.

I run a minimum of 3/4 pipe for the drops and limit my hose to 10 or 15’ unless I need some reach. Most of my hoses are 1/4” Parker and I never have flow issues. The hose isn’t long enough to cause an issue on most tools.

Most air tools will run AMAZING on low pressure but high VOLUME. I ran a die grinder main lined off a tow behind screw once. Pressure was only 80psi or so, but I had 50cfm available. That die grinder woke right up and worked better than it had ever had.

The couplers rarely are the hold up. It’s almost always the compressor and pipework resisting flow for common air tools.

 

[Shop-hound]

I think the best post to illustrate this need/finding is here:

Air Couplers: HIGH FLOW low flow vs LOW FLOW low flow.

(For informational purposes only) I wager most air tool users are not aware of this. It's a fact that some standard couplers have much better flow than others using the same M style plugs. For example: Conventional M style coupler: 41 PSI pressure drop with 1/2" impact free running at 90...

www.garagejournal.com

Some of the standard M couplers are so restricting that they choke off the flow to the tool. Standard home setup with say max 130 psi at the reg, you would be unable to overcome this pressure drop and tool power suffers

 

[dr_clyde]

I’m not saying couplers don’t restrict flow, I’m just saying in most cases it doesn’t really matter.

If they truly were a problem, they wouldn’t be an industry standard. Profit making companies tend not to put up with things that get in the way of their making money. I’ve plumbed several industrial pneumatic systems with 1/4” couplers and never had flow issues because the rest of the system was piped properly. We ran LARGE diaphragm pumps and other big tools off a standard 3/8” air hose and 1/4” couplers. If they didn’t work, we would have ditched them right away. Any time we ran into a weird or nonstandard coupling, we trashed it immediately in favor of uniformity and ease of system maintenance.

I’ve never NOT been able to use my air tools because of the couplers, except if I tried to run my 3/4” impact off a 1/4” hose/coupling in a pinch. There is noticeable decrease in performance there.

Small and common air tools are designed to work with common air systems. Including the couplers.

Big tools like more air, and it makes sense to upgrade to bigger couplings for large impacts, blasters, or other air hogs like angle grinders. But for MOST things, 1/2” or 3/8” impacts, die grinders, sanders, nailers, inflators, nozzles, etc, it’s just not needed.

I don’t want to have to source special couplings and fittings when I can get what I need at ANY industrial house, auto parts store, big box house or even at HF if I’m desperate.

Special high flow couplings WORK BETTER. No argument. But I don’t think the juice is worth the squeeze. It seems like a solution in search of a problem more often than not.

 

[whateg01]

I don't understand the desire to carry around several pounds more hose and coupling weight for things that don't need it. Since the majority of flow loss is due to the pressure drop on a long hose in many instances, why not use the long hose for the majority of the run then a short whip at the end on the tool? I can't imagine holding an impact with a 1/2" hose over my head working under car for any amount of time!

 

[Stedlin]

I used plain old brass industrial 1/4” couplers similar to the Milton 715 for well over 30 years in a manufacturing environment.

Only had an issue with flow a few times. When I did I eliminated the coupler.

They are however very flow restrictive, leak prone and can be a pain to connect.

They can easily have a larger pressure drop than the hose. The Stedlin coupler and some others can increase the flow using a common 1/4” m style plug by about 90% at a pressure drop of 5 PSI.

Putting a short smaller hose at the end of a larger hose makes a lot of sense.

 

[dr_clyde]

I used plain old brass industrial 1/4” couplers similar to the Milton 715 for well over 30 years in a manufacturing environment.

Only had an issue with flow a few times. When I did I eliminated the coupler.

They are however very flow restrictive, leak prone and can be a pain to connect.

They can easily have a larger pressure drop than the hose. The Stedlin coupler and some others can increase the flow using a common 1/4” m style plug by about 90% at a pressure drop of 5 PSI.

Putting a short smaller hose at the end of a larger hose makes a lot of sense.

Please understand I’m just having a discussion and am not slamming you or your product in any way. OP may have a niche case where the ease of coupling makes more sense for him in his home shop to switch than any argument I could make. I just like the discussion and debate.

Obviously you make and sell a product here that is designed to be better than the standard fare, I would expect you to argue in favor of your product.

I’m not arguing the science or efficacy of the high flow couplers. They are better, and I wish they were the standard, but they’re not. I’m not going to swim upstream and fight a system that by and large isn’t broken.

What I am saying is that it fixes a problem that just doesn’t exist for most people. If it ain’t broke, I’m not going to spend time and resources replacing what already works just fine for very minuscule gains. Even if you sent me enough couplers to swap over my whole shop for free, I still wouldn’t do it. It would take an industry shift if a massive magnitude to make me shift. I want to use what the standard is. Parts need to be available on McMaster and at the supply house.

Look at the Phillips and slotted screw heads. There are better designs, and have been for decades. And yet we still have Phillips and slotted screws, and they still work for 99% of the applications they’re in. Torx is better in almost every way, and I suspect it will take an act of congress to get Phillips and slotted screws out of use.

There is value and worth in using standardized systems. As much as I like the metric system, I can’t remember effectively use it in the USA because our infrastructure and way of life isn’t set up for it. It would take twice as much effort and headache to use a system that is objectively better in every single way.

Until my air tools cease to be useful and functional with the system I have, I just can’t see a reason to change.

Hopefully OP can find a coupler they like.

 

[GeoBruin]

Please understand I’m just having a discussion and am not slamming you or your product in any way. OP may have a niche case where the ease of coupling makes more sense for him in his home shop to switch than any argument I could make. I just like the discussion and debate.

Obviously you make and sell a product here that is designed to be better than the standard fare, I would expect you to argue in favor of your product.

I’m not arguing the science or efficacy of the high flow couplers. They are better, and I wish they were the standard, but they’re not. I’m not going to swim upstream and fight a system that by and large isn’t broken.

What I am saying is that it fixes a problem that just doesn’t exist for most people. If it ain’t broke, I’m not going to spend time and resources replacing what already works just fine for very minuscule gains. Even if you sent me enough couplers to swap over my whole shop for free, I still wouldn’t do it. It would take an industry shift if a massive magnitude to make me shift. I want to use what the standard is. Parts need to be available on McMaster and at the supply house.

Look at the Phillips and slotted screw heads. There are better designs, and have been for decades. And yet we still have Phillips and slotted screws, and they still work for 99% of the applications they’re in. Torx is better in almost every way, and I suspect it will take an act of congress to get Phillips and slotted screws out of use.

There is value and worth in using standardized systems. As much as I like the metric system, I can’t remember effectively use it in the USA because our infrastructure and way of life isn’t set up for it. It would take twice as much effort and headache to use a system that is objectively better in every single way.

Until my air tools cease to be useful and functional with the system I have, I just can’t see a reason to change.

Hopefully OP can find a coupler they like.

Wait, I'm confused. Stedlin's couplers are "standard". They accept any industrial style plug I've ever tried. I have several of his full flow plugs around the shop as well but I have just as many brass and steel plugs from the likes of Milton and even Harbor Freight.

What is non-standard?

 

[dr_clyde]

Wait, I'm confused. Stedlin's couplers are "standard". They accept any industrial style plug I've ever tried. I have several of his full flow plugs around the shop as well but I have just as many brass and steel plugs from the likes of Milton and even Harbor Freight.

What is non-standard?

Can I buy it at any hardware store? Industrial supply house? I don’t want to be special ordering hardware when I can buy what I already have that I know works anywhere that sells tools and hardware.

 

[Cruzan80]

I think what ypu are missing is the couplers and plugs work with anthing you can buy at a supply house. So putting them in the mix doesnt affect anything else, just gives you more air for the tools you care about. Add them where you want, and "standards" play nice with them.

 

[dr_clyde]

I think what ypu are missing is the couplers and plugs work with anthing you can buy at a supply house. So putting them in the mix doesnt affect anything else, just gives you more air for the tools you care about. Add them where you want, and "standards" play nice with them.

That’s for sure a bonus, and not something that is plainly obvious.

However, until products are available from distributors and places where I have accounts it will be a non starter. Especially when my current couplings work fine.

 

[Cruzan80]

Ok, but that is different than "standardized". It is like saying someone made a JIS screwdriver that fit both JIS and Phillips, but you refuse to buy it as it isn't sold at Home Depot...

You do what works for you, just seems like a very arbitrary line to draw.

 

[dr_clyde]

Ok, but that is different than "standardized". It is like saying someone made a JIS screwdriver that fit both JIS and Phillips, but you refuse to buy it as it isn't sold at Home Depot...

You do what works for you, just seems like a very arbitrary line to draw.

It wasn't clear from the beginning that these couplers would accept normal fittings. Most high flow couplings come in pairs.

But my statement stands. I'm not going to go out of my way to fix what isn't broken, and if I need to buy things for my business, I will source from the many places I have accounts with.

 

[Cruzan80]

So the very beginning of this thread was about type G couplers, which only fit other type G. Generic supply house style.

If you meant Stedlin wasnt clear about his fitting other couplers, that is probably because he didnt start this thread, and was only using his rig to test if they were helpful or not, initially.

Again, nobody is forcing you to buy Stedlin stuff. But if you have to buy and replace stuff anyway, it is saying you are only going to buy Craftsman RP ratchets, because you have an account at Sears, while everyone else is saying how nice Snap-Ons Dual 80s are. Both turn a socket, one is nicer to use, but you have made it clear setting up another PO account is too much work for what you see as a lack of benefits.

Just because what you have works, doesnt mean there isnt a better way to accomplish it, while still fitting the "industry standard". And FWIW, I dont have any Stedlin, but plan on getting some once everything I have is solidified.

 

[Shop-hound]

I’m not saying couplers don’t restrict flow, I’m just saying in most cases it doesn’t really matter.

If they truly were a problem, they wouldn’t be an industry standard. Profit making companies tend not to put up with things that get in the way of their making money. I’ve plumbed several industrial pneumatic systems with 1/4” couplers and never had flow issues because the rest of the system was piped properly. We ran LARGE diaphragm pumps and other big tools off a standard 3/8” air hose and 1/4” couplers. If they didn’t work, we would have ditched them right away. Any time we ran into a weird or nonstandard coupling, we trashed it immediately in favor of uniformity and ease of system maintenance.

I’ve never NOT been able to use my air tools because of the couplers, except if I tried to run my 3/4” impact off a 1/4” hose/coupling in a pinch. There is noticeable decrease in performance there.

Small and common air tools are designed to work with common air systems. Including the couplers.

Big tools like more air, and it makes sense to upgrade to bigger couplings for large impacts, blasters, or other air hogs like angle grinders. But for MOST things, 1/2” or 3/8” impacts, die grinders, sanders, nailers, inflators, nozzles, etc, it’s just not needed.

I don’t want to have to source special couplings and fittings when I can get what I need at ANY industrial house, auto parts store, big box house or even at HF if I’m desperate.

Special high flow couplings WORK BETTER. No argument. But I don’t think the juice is worth the squeeze. It seems like a solution in search of a problem more often than not.

In an industrial environment with higher pressure compressor (twin screw / dual stage etc) I'm sure you can overcome it by cranking up the PSI in your system (175 required to offset 90 psi drop to get 85 pounds at gun worst case as per test rig in Stedlins post). For straight cost and simplicity that will work. Assuming the couplers used in that test are total junk and real world industrial type Ms lose less, youre still looking at at least 45 psi drop. For my situation where the tank is max 150 psi, I'm usually only getting 130 psi at mid tank (before it kicks back on). When the car/truck is on stands and I need that bolt out/wheel bearing/balljoint any extra jam can be the difference between getting the job done and suffering for hours. Hey, if we were all OK with less power, why do we pull out straight 6's and put in big blocks? Swap the crank and make a 350 a 383 stroker etc. Hey this is GJ, More power = good

I can appreciate all opinions, but embracing innovation, not accepting status quo and trying to make a better mousetrap is what makes industry, engineering and our 2 countries (I'm a Canadian), great.

And some patriotism to keep it all in fun, I cant resist the Philips head screw comment. That design certainly has its flaws. Up here in Canada, invented the Robertson (square drive) - much less apt to cam-out, but Henry Ford didn't want to pony up the $ to pay to use it on the model T which is credited to its popularity. Most of our wood screws here are Robertson. I wont save Philips drive screws in my fastener bin system if I'm taking something apart, they get pitched. But I sure as heck need to have my wera #1 and #2 philips drivers at the ready as the dang things are everywhere

 

[rumb]

Why nobody uses CEJN? It's very well made HI FLow couplers. Little pricey, but I like it. I use 320series. End eSafe series prevents pops out, then disconnecting.