Tools, Sharpening and Power Machinery - 3/8 vs. 1/2 air hose, PVC vs. Rubber

I just picked up a Cranftsman 25 gal, "6hp" belt drive compressor (8.6@90, 6.8@40, 150psi) to upgrade from my cheapo $90 harbor freight compressor that I've had for about 2 years.

I primarily want to use impact wrenchs, ratchets, etc for automotive work at home.

I want to have a 50' hose to use for working in the basement near the compressor, as well as a 100' length for getting outside when needed. I assume I'm fine with 3/8 on the 50', but should I bump up to 1/2 for the 100' run? Will this likely mean a bump from 1/4NPT to 3/8NPT on the fittings?

Is there a general rule of thumb for pressue drop by line distance and diameter? I want to make sure I set the regulator for the proper pressue according to what hose I'm using.

Also, are most of the quick connects I see for sale a single size, or do I need to worry about different connectors not mating up? I don't want to have to switch the fixed couplers on the tools when I switch hose diameters.

Finally, is there a functional difference between the rubber and PVC based hoses? Should I go with one over the other?

Thanks in advance,
Chris

Note: I tried searching for this here, but didn't really couldn't find my answer. Is there a way to access the standard vBulletin search engine on this forum? It's usually a lot easier to narrow down a search with that. Here I just sort of get everything back and can't make sense of what's a post, what's an article, etc.

Hi Chris,

I have two ceiling mounted air hose reels, one with the 50' orange (poly) and one with the 100' red rubber hose.

There is a formula for pressure drops over long runs. Check your compressor instructions and it may be stated there. Otherwise, as best I recall, it's a 5 psi drop for lines over 100 feet, all other things being equal.

Of course bigger is better when it comes to hoses, but even with your 100' line, you could stay with 3/8" hose and bump the pressure up. The 1/2" line is expensive for 100' and much heavier to lug around. Reels cost more too. My rubber reel contains 100 ft of rubber 3/8" hose and works fine with air tools, with the exception of maybe my hefty sand blaster which is a super air hog. All 3/8" line is designed to accept the common 3/8" quick connects.

And yes, larger fittings for larger lines will elimimate bottlenecks that calculate into the overall volume of air delivered. It is self defeating to put undersized connectors on 1/2" supply lines.

The only time I have seen 1/2" line on air guns are for roofing and framing crews that use manifolds to share a line.

Yes, there are many, perhaps 6 or more different types of commonly available quick connects. For example, the disconnects sold at auto supply stores will be a little different from those sold at lumber yards.
Pick the simplest design at the lowest price and most importantly, a style that is AVAILABLE everywhere you shop. Some of the connectors look identical but are not compatible. When you visually inspect a style to attempt to identify its compatibility, start by looking inside the female coupler and count the number of ball bearings you see. Some don't have ball bearings visible, most do. Some have 3, some have 4 or more, etc. All my connectors are generic, 3 ball bearing connectors. I buy them, male and female, a dozen at a time at Harbor Freight cause they are dirt cheap.

Rubber verses pvc? Pvc(poly?) is attractively priced and extremely durable, but tends to coil up as it is unwound and then snags everything it can as it is dragged across your work site.

Rubber lays flat as a limp noodle and is a joy to work with. Alas, there are trade offs, such as ease of cleaning, resistence to grease, nicks and scratches, max pressure, budget, replacement cost, etc.

Orange pvc (poly?) is more bang for your buck and very popular with contractors and DIY'ers.

I don't recommend one over the other. However, I use both, and my personal preference is for 3/8" rubber.

Actually, I also own a new specialty hose that is 'thin poly'. Thiner walls than regular lines, and supple as rubber, but cost about $100 for 50 feet. Now that hose is a luxuary, but a dream come true to use for portable compressors.

Orange pvc (poly?) is more bang for your buck and very popular with contractors and DIY'ers.

I don't recommend one over the other. However, I use both, and my personal preference is for 3/8" rubber.


Orange pvc also gets stiffer in the cold
Real stiff
But I also will run a (length of orange to the outbuilding I'm in
Then connect my (prefered) rubber hose to it at the door, and use the rubber in the work area

I went with the Craftsman connectors mostly because I figured they would always be available and I'd know where to get them and there'd be no confusion as to compatabilty

Thanks for the info guys.

I already have a few packs of Harbor Freight cheapo couplers that don't seem to leak, so maybe I'll stick with those for now.

I picked up a 50' 3/8 Goodyear hose today at HF actually, but I didn't get a 100' length yet because I wanted to get some more opinions on diameter. After looking at the 1/2 diameter hose, I could definately see where it would become a bit bulky to work with. I wound up going with the rubber, since it seemed like it would be a little easier to work with (I can see how PVC would freeze or coil-bing easier).

As long as I can run some of the lower CFM tools I need for automotive work I should be fine with the smaller diameter. If I was doing anything that required lots of flow, I'd just move the compressor closer.


Is it possible for one (me) to make my own length hoses at home? I could see the need to have some shorter lengths, or should I keep shopping around to find some misc lengths at different stores?

Also, do you guys running hose reels near the compressor just have a 15' coil of hose coming of the compressor that you attach an H20 filter to? I plan to have my reels right next to the comp. but it seems like I should have the water filter in there too. Everyone recommends that I keep it 10-20' from the outlet to allow the air to cool and vapor to condense, but the only way to do that is to have "dead" line in middle. I'm not putting out _that_ much CFM that I want to unnecessarily increase my runs.

Thanks,
Chris

You can make your own lengths with ribbed couplers, no problem there. I avoid doing that and design my needs around standard lenghts and including those shorty yellow plastic cheap coils ($5) if needed at the end of a run to the gun.

My filter and regulator are at the reel, 20 feet from the compressor. By accident, not by design, lol.

I run 1/2" steel pipe from the compressor in the basement (quiet and clean there) to the garage reels. I have a steel pipe network and you will likely not have a steel pipe supply line. I never really thought about distance between the compressor and the water filter. Could be some logic to having it farther away. But don't increase your run unneccesarily.

25' lines are harder to find. Most stores only carry 50 and 100 anymore. Keep that in mind when you layout your shop. And a 25' line cost the same as a 50', minus $3.

Don't stew over the layout. Just about anything will work excellent.

P.S. I don't have an oiler in my lines because I also use them to spray paint. Keep that in mind. Once you put in an oiler, you should never use the line to spray paint. I oil my guns manually, or put a snap on oiler at the gun.

Chris,

Having a coil of hose between the compressor and water separator will help a bit but not enough to make that much of a difference.
Where you get the most water is when you consume a continuous supply of air where the reciever tank and hose warm up.
Because the hose is rubber, it partially acts as insulation and you really don't cool the air down that much.
If you had a piped system then you would dissipate a fair bit of heat and it would be worthwhile to put the filter at the end of the line.

As far as making up your own hoses I don't think you could buy bulk hose and the fittings as cheaply as ready made ones, especially if you buy them at HF. Plus, if you were to use barbed fittings you would either have to buy a crimper and ferrules to attach the hose or use hose clamps that get caught on things when you try to haul the hose in.

I assume that your 3/8" hose has 1/4" fittings.
You can get 1/2" hose with 1/4" fittings as well. There will be a slight restriction at choking it down but you would hardly notuice it.

Well, I don't plan to put an oiler in my lines at this point in time. I hear over time they can gum up the equipment because of over oiling. Regardless, I don't really mind putting a drop of oil in the tool when I use them.

Maybe I won't bother with the excessive length of hose between the compressor and the filter, since you're right about the rubber being a good insulator. In that case, I probably don't need to worry too much about some custom length lines.

I know what you mean about not being able to buy bulk stuff as cheap as HF. I couldn't believe 50' of 3/8" Goodyear hose, made in USA, was only $19. I think I will go back and get a 100' length in 3/8 for now too. If I find myself having pressure issues, I can always upgrade in the future. Since my compressor will do 150psi, I should be able to regulate the output pressure to compensate for any pressue drop across the length provided I can get the flow I need.

I definitely don't need to worry about steel piping at this point. When I move in a few years, maybe I'll upgrade to a heavy duty 240 upright compressor, until then I've still got a pretty portable setup.

Ha ha I just realized you've got the same "portable" I do, Chris F.
At least I think so
If it's this one:
Whups...guess they won't let us post pics any more
:(

Anyway, I'm pretty sure you have the newer version of mine (man I think it's 10 yrs. old now)
I regularly run 100 ft. w/no problem or significant drop
Or any noticable drop for that matter
You won't need a bigger dia. hose
You probably won't have to upgrade anytime soon
You may want to switch it over to 220 if you use it alot, that's all

Can I get more air out of it at 220, or is it just cooler/easier on the motor and my wiring?


I have this one:
<img src="http://content.sears.com/data/product_images/009/19541/00919541000-190.jpg">
Image credit: sears.com

<a href="http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00919541000&subcat=Portable+Tank+Compressors">compressor</a>

"Can I get more air out of it at 220,"
No.
It not going to change the RPM


"or is it just cooler/easier on the motor and my wiring?"
Yes.

By golly, it looks just like mine too. My 2 wheel model is brand new, replaced by an insurance company after a theft a while back. But it's in a locker not at my house, with some other tools. If it is, its a beauty of a compressor. It kicks ass AND it runs quieter than anything, bar none, than I have ever owned before.

I have 5 compressors,(all in excellent working condtion) from 60 gallon down to the porter cable pancake.

Yup that's it
Though my older version isn't that quiet
How'd you post a pic?

How'd you post a pic?

You can use regular HTML here, but not the [ img ] code apparently.

So you would say: [img src="http://content.sears.com/data/product_images/009/19541/00919541000-190.jpg"]

except replace the [ and ] with < and >

Images are ok but we have to be careful with copyrighted material.
If you post an image and don't own it, you must credit the owner as I've done above .

Images are ok but we have to be careful with copyrighted material.
If you post an image and don't own it, you must credit the owner as I've done above .
Gotcha....will do in the future.

Thanks Chris F.
I think that's how I used to do it
And thanks GregH, that's probably why WeldGod's how to post is unaccessable when I checked it to remind myself how
There certainly is a point there about uncredited images
I'll remember to credit them from now on