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-   -   AN Fittings (https://vansairforce.net/community/showthread.php?t=146218)

rongawer 01-30-2017 07:25 PM

AN Fittings
 
I want to pass on that I received excellent products at a low price with quick shipping from AN Fittings Direct http://www.anfittingsdirect.com

I had a couple questions and they were very responsive. The PTFE hose is very good quality and the fittings, while not the exact same finish as Aeroquip, are well made and fit well. I did my brake lines at the pedals and to the reservoir in -4 (I did all of my lines aft of the forward tunnel in hard line -4), FWF fuel lines in -6 and my oil lines to the cooler in -8. I also bought several different fittings from them and found them very satisfactory for the job.

I am very happy with these folks and recommend them.

DanH 01-30-2017 08:54 PM

What makes you think those are real AN fittings?

Captain Avgas 01-30-2017 10:56 PM

Quote:

Originally Posted by rongawer (Post 1146241)
The PTFE hose is very good quality and the fittings, while not the exact same finish as Aeroquip, are well made and fit well.

I hate to be a downer but:

a) This is automotive quality stuff and probably consists of cheap Chinese imports.
b) There's probably no recorded quality control or source chain documentation on the components.
c) The PTFE inner liner is probably not "conductive" as all aviation grade PTFE hoses are.
d) It is most unlikely that the assembled hoses have ever been tested to proof pressure as all aviation hoses are.

You can't tell anything about the quality of auto hoses just by looking at them. :rolleyes:

BillL 01-31-2017 07:28 AM

Thanks for the tip Ron. Agree you should check for the conductive liner of using for oil or fuel.

Did you pressure check these hoses to 3-400 psi and leave the pressure on there for 30 min? That is the best way to see if they are holding. Since there is no serration against the PTFE, (like all other products) heating to cowl temps with a hair dryer while pressurized would be in order.

I used some aeroquip hoses, but automotive racing type. I held them highly suspect and did research for the fittings. Each assembled hose was pressure tested with oil to 3-400 psi - one accidentally to 600 psi. I left the pressure on there for an hour to be sure. Keep in mind that the engine oil filter has a burst higher than 400 psi.

Don't want to be critical of your find, but just to be sure it is vetted, tested, and safe.

Brakes would be fine.

rongawer 01-31-2017 10:19 AM

Quote:

Originally Posted by DanH (Post 1146271)
What makes you think those are real AN fittings?

Uh, the dimensions.

rongawer 01-31-2017 10:35 AM

Quote:

Originally Posted by Captain Avgas (Post 1146294)
I hate to be a downer but:

a) This is automotive quality stuff and probably consists of cheap Chinese imports.
b) There's probably no recorded quality control or source chain documentation on the components.
c) The PTFE inner liner is probably not "conductive" as all aviation grade PTFE hoses are.
d) It is most unlikely that the assembled hoses have ever been tested to proof pressure as all aviation hoses are.

You can't tell anything about the quality of auto hoses just by looking at them. :rolleyes:

A: true, but so is a majority of hardware.
B: True, but I'm building experimental. If you're actually generating FAA-8130 docs for your airplane, more power to you - but I doubt most (if any) people do that.
C: Their PTFE is impregnated with carbon, which conducts and eliminates static buildup.
D: I pressure tested mine to 150psi for 1 hour with no leaks noted. Again, if you really need a 10,000 psi hose for your 45 psi fuel line (fuel injected), then have at it.

Considering that I've built my lines and tested them, I feel confident in them. If you choose to just say I'm wrong, well then we simply disagree.

rongawer 01-31-2017 10:52 AM

Quote:

Originally Posted by BillL (Post 1146337)
Thanks for the tip Ron. Agree you should check for the conductive liner of using for oil or fuel.

Did you pressure check these hoses to 3-400 psi and leave the pressure on there for 30 min? That is the best way to see if they are holding. Since there is no serration against the PTFE, (like all other products) heating to cowl temps with a hair dryer while pressurized would be in order.

I used some aeroquip hoses, but automotive racing type. I held them highly suspect and did research for the fittings. Each assembled hose was pressure tested with oil to 3-400 psi - one accidentally to 600 psi. I left the pressure on there for an hour to be sure. Keep in mind that the engine oil filter has a burst higher than 400 psi.

Don't want to be critical of your find, but just to be sure it is vetted, tested, and safe.

Brakes would be fine.

I appreciate the advice. I answered your comments about conduction and testing earlier, but I'll add that you only need conductive lines for fuel, not oil; engine oil won't won't flash on static charge.

As a engineer who builds and operates power plants for a livings, I will tell you the ASME standard is 150% of system rated pressure for hydrostatic pressure testing. Going to 10 times the rated system pressure is a little pointless to me. Build your system to meet the need. For pressure testing small lines like these, I simply submerge the pressurized line into water and do a bubble check. If it will hold 3x system pressure for an hour, it will hold system pressure just fine. Going above that is unnecessary, but I won't discourage folks that feel they need that type of security.

What's really hilarious to me is that I'm pointing out an inexpensive supplier of braided steel hoses and I'm told to avoid automotive hoses. This coming on a forum where the majority supplier (Van's) provides plastic hoses for brake lines with brass compression fittings that you can get at Ace hardware = and they do the job just fine.

Keep in mind, that if you build your airplane with everything redundant, you'll have two airplanes... in the end, it's your money, have it, however I'm hoping someone reads this and finds it useful.

DanH 01-31-2017 11:31 AM

Quote:

Originally Posted by rongawer (Post 1146394)
Uh, the dimensions.

$20 bucks says those are cheap knockoffs that do not meet the AN standard.

Same folks also sell "ninja swords": http://www.wildweapons.com/

bret 01-31-2017 12:02 PM

I did my entire EFII fuel system with this stuff, 800 PSI, 304 SS, 500 deg rating triple grip fittings, outer coating, carbon impregnated PTFE hose. There was a learning curve and took a long time to build the 12 lines, but they all pressure checked out and no leaks. I like the swoop no sharp corner 90 deg fittings. I will keep a sharp eye on all these lines, but I like how it turned out. http://www.anfittingsdirect.com/stai...es-p-1240.html

rongawer 01-31-2017 12:45 PM

Quote:

Originally Posted by bret (Post 1146429)
I did my entire EFII fuel system with this stuff, 800 PSI, 304 SS, 500 deg rating triple grip fittings, outer coating, carbon impregnated PTFE hose. There was a learning curve and took a long time to build the 12 lines, but they all pressure checked out and no leaks. I like the swoop no sharp corner 90 deg fittings. I will keep a sharp eye on all these lines, but I like how it turned out. http://www.anfittingsdirect.com/stai...es-p-1240.html

I'm with you; there was a little learning curve to get the first one done, but after that it went pretty smooth. I just finished my fuel, oil and brake lines and they are solid construction, tested well and they look good too.

Just because it wasn't expensive and didn't come with an FAA certification tag doesn't mean it doesn't work well. Anyone who thinks their experimental airplane is being built to the same standard as a part 23 aircraft is really missing the point of "Amateur Build". As the saying goes, "caveat emptor".

I used uncoated braided lines to save a little weight, http://https://www.anfittingsdirect....es-p-1200.html, but the TPU coated ones look good too.


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