I spent a while looking for good compressor hose. My compressor had two hoses, a nice old hose made from EPDM rubber, with great quick connector, and a HF (Harbor Freight) hose. HF rubber hose lasted a little over a year and basically cracked and started leaking. I then spent a while asking questions and looking for good air hose. I wanted a hose that
1) lasts a long time
2) is flexible in cold weather.
I bought "Pliovic" air hose from HF and had to return it back to HF because it did not satisfy criteria #2. It was unusable in cold weather.
Then I looked for EPDM rubber hose, it was hard to find, found some at McMaster but it was very expensive.
Finally I found this hose. It was made by Thermoid from EPDM rubber,
3/8" ID.
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It arrived today (7 days). It is definitely flexible in cold weather and seems to be made of the same quality stuff as my good old compressor hose. I like it a lot so far.
For the female fitting, I bought one at McMaster instead of using HF female fittings. HF female fittings leak air.
Anyway. The result is that I have a nice flexible hose, have a feeling that it will last a while longer, and the air couplings do not leak at all, even when subjected to bending like when a hose is kinked.
I bought a pile of used Boeing air hose at Boeing Surplus when they were selling it for ten cents a pound. That stuff is real nice. They use Dynaquip fittings, which cost a lot more than the cheap ones but which work really nicely.
Some time ago I was buying something from a guy and he asked me if I wanted some bulk air hose. In a weak moment, I said "sure" and now I have a biggish reel of
3/8" black Goodyear air hose, which is also nice stuff.
I'm probably never going to be looking for air hose again!
I had some push-loc hose I bought from a dealership that went out of business. Best air hose I've ever used, I've been trying to find a place that sells the stuff.
It could be the kind of hose that I just bought. Similar to great hose that I had come with my compressor. EPDM rubber is the material. Soft, easy to coil and uncoil, and does not crack so quickly.
I think that they sell approximately what I have, EPDM rubber hose. I worked with it some yesterday, and was very satisfied. Night and day compared to "Pliovic". I uncoiled it for the first time, in relatively cold garage, and it laid down on the floor perfectly flat. Light and flexible.
Thats the hose, if the hose connection starts to have problems, just cut a half inch off and reinsert the hose connection. Downtime due to hose problems is never a problem. Cold weather doesn't effect it.
Gack! Another one of those sites that won't give the prices up front. "Call for a quote" - no thanks. These people, and plenty of others, are unclear on the website concept. Probably an old time company that is trying to be modern but just doesn't have the right mind set.
My air hose is Aeroquip push on hose. It is actually rated for oil lines so it holds up well in shop use. I use about 15 feet 1/4" hose at the tool,
3/8" up to that. All my hoses are 20+ years old and still in good condition. This hose is stiffer than some, by I find it acceptable. I don't now what it would cost today, but when I bought it, it was $1.25 a foot, plus a couple bucks for each hose end. Well worth it in the long haul. I had bought numerous brands, and qualities of air hose up to the time I went with the Aeroquip hose and none of it lasted over a year in a engine shop environment.
I followed the original thread and this one with interest. I hoped the thread would point me to a hose with the ideal flexibility. But "flexible" has to be one of the most subjective properties. Hoping to get some handle on it & create an objective measure, I came up with this: define flexibility as the inverse of the radius of the bend under a fixed load. The more flexible the hose, the smaller the bend radius for a given load.
Now, to actually measure this in a shop environment. As a standard load, I chose a given length of hose - 12". The load weight will vary somewhat with different hose densities, but I feel the ease of implementation outweighs that. Then the measure is made by holding the hose horizontal with the 12" extended and measure the radius. Rather than tackle the awkward task of measuring the actual radius, I chose to measure the vertical deflection of the extended hose, which is inversely proportional to the radius. The test rig is a framing square held in a vise 8-)
The result of some trials:
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The 1st (hose3) is what I consider to be ideal for tool "whips". Almost as flexible as SO electric cord and as such has minimal interference with the movement of the tool. It's modulus is an amazing 11 1/4". The next one (hose4) is almost as good (10"). The last one (hose5) is one of 3 hoses that were the same stiffness (2 1/2"). And is typical of most hoses that I've seen. I don't consider this last, stiffest, one to be suitable for direct connection to a tool. Note that these are all what I would call "rubber" and not that awful plastic stuff which I don't own and would probably have a flexibility modulus near zero (no droop at all in the test rig).
Part of the test load is a 1/4" male barbed fitting - I wasn't going to cut it off for purity's sake. The hoses all had a set to them and I was careful to position them so that the set was horizontal. I.e., so that the set did not affect the deflection. I did this by coiling them on a flat surface and marking the top:
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top was then held against the framing square while the coil was held horizontal (!) off to the side. This can easily be done by hand, but I had to clamp it in place for the pix.
Now that I've quantified the flexibility of some hoses, the results are totally useless to anybody, including me, because I have no idea what these hoses are made of or who made them!! Well, not totally useless, there are 2 uses for the data: I can go to a store, grab a piece of hose, and eyeball the deflection of 12" of it. It shouldn't be hard to tell if it's a 3" or 10" modulus hose. The second use would be if some of you out there in RCMland would measure known brands and report their flexibility.
Bob
PS - the modulus should be dimensionless, I suppose. So using the ratio of vertical deflection to overall length could be used. E.g., 11.25/12 = .94 for hose3. But I suspect that it doesn't scale. E.g., a 36" piece of hose3 would probably not deflect 3 x 11.25. More or less? I dunno. And deflection in inches is just as convenient.
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