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Braided Teflon Hose

Grinning Dad

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I am a newbie here and although I've been lurking on these forums for a while, I am still figuring out how this all works.

I recently bought a project RV10 that the previous owner has a little more than 2900 hrs logged. He had installed plastic brake lines and aluminum fuel lines. The fuel lines would be fine, but I need to modify the installation to make room for a flyefii system 32 fuel supply and I don't like the plastic brake lines. I am hoping for some advice on braided teflon hose. I am hoping that it makes sense to buy bulk and build my own but would like to tap into the advice on this forum. I'm coming from behind on the build, but feel like a little boy in a candy shop! Thanks
 
I just realized that I didn't ask for any specific advice.

What hose supplier have you used and recommended?
What size do I use? I see internet recommendations for an-3 hose for brake.

This is smaller than the plastic lines currently installed which makes me curious as to what this community recommends.
 
Aircraft Specialties

Talk to Steve at Aircraft Specialties. Great quality hoses and they are custom fit for your set-up. Just tell him make, model and mods. For EFII you will need return fuel lines to the tanks. He can do those also.
 
My C180 has 1/4" aluminum lines down to the brakes, and it's been doing fine for over 3,700 hours and more than 65 years. I plan to do the same for my RV-3B.

Note that both are taildraggers, and perhaps have longer landing gear legs than your plane, which would increase the flexibility of the tube. Also, I'm using 3/16 tube on the RV-3B, for more flexibility and frankly, for a small weight savings.

Dave
 
There's no rocket science to building braided lines. Really there's only 2 suppliers of aerospace hose, Aeroquip and Stratoflex. A little internet searching will turn up hose specs and recommended fittings. Use the correct fittings for the hose. If you are just building 1 hose you can probably get away without a mandrel. If you are doing a plane get mandrels. You may be able to borrow mandrels from your EAA chapter or a local a&p.

Avoid angled hose ends like the plague. They are ridiculously expensive, and make it really hard to inspect the hose. You can almost always install some sort of angled fittings or adapters on whatever the hose is connected to.

If you are buying everything new the specialty shops may be price competitive with doing it yourself. Cheap *******s like me procure old hoses and salvage the fittings.

I'm not sure I'd try to build my own brake lines. Those lines are really small, and the fittings normally crimped. There's a lot of pressure there.
 
Hi Dennis----NO ONE uses a mandrel to make teflon hoses. NOR a 701 style braided rubber hose. You are referring to a H8794, or 303 style hose that is rubber under the nylon braid, under a steel (not stainless) braid, then uder the cotton cover. And for straight stems only. Ever wonder how you'd get a mandrel to go around the inside bend of an angled fitting to install it on a hose?

Most all reusable hose ends for teflon use some sort of sealing unit, like an 'olive' that separates the teflon liner from the braid, thus the sealing section from the retention section.

As for angled fittings, wonder why Aeroquip, Stratoflex, Smiths Titeflex, Teleflex Aero Hose and several others, like AS Flightlines, make 45*s, 90*s, and other such fittings? Because bending a hose to work in a confined area may not be appropriate. Generally all of those hose ends are made from a 1 piece bar stock, or brazed/welded precisely cut angles and the stems and flare heads.

And as for this statement, " Cheap *******s like me procure old hoses and salvage the fittings", if its a crimped teflon hose end, you wont salvage the fitting, without (generally) destroying the crimp collar. Even if you do, I'll bet you dont have an expansion mandrel to bring the stem ID back to spec.

Yes Aeroquip and Stratoflex ARE the heavy hitters in the aerospace industry--but there are several others as I mentioned earlier, that are also there, but may not market in the commercial GA arena. Several deal in heavy commercial and military contracts. Most dont market in the experimental arena, but those that do have a very complementary product to Aeroquip and Stratoflex.

Dont be scared of a -3 or -4 hose with resuable hose ends. Its just a hose.

Tom
 
Its cool, as there are rubber lined stainless braided hoses. They also dont require a mandrel. Some are cutter style stems, some are expansion style stems.

Tom
 
I am a newbie here and although I've been lurking on these forums for a while, I am still figuring out how this all works.

I recently bought a project RV10 that the previous owner has a little more than 2900 hrs logged. He had installed plastic brake lines and aluminum fuel lines. The fuel lines would be fine, but I need to modify the installation to make room for a flyefii system 32 fuel supply and I don't like the plastic brake lines. I am hoping for some advice on braided teflon hose. I am hoping that it makes sense to buy bulk and build my own but would like to tap into the advice on this forum. I'm coming from behind on the build, but feel like a little boy in a candy shop! Thanks

I just sent you a private message.

Regarding the plastic brake hoses...... they can be replaced with either -3 or -4 size hoses but for the rv-10 stock brake configuration we utilize -4. If you do a Beringer setup we go with -3 size. Both are completely adequate for the installation. As a reference we built several brake hoses for “Scrappy” in -3 size.....and we have seen the videos of what Mike does with that plane.

As far as the EFII system....... it’s a tight fit but completely doable. If using flexible conductive Teflon hose you will have areas in the system that require angle fittings due to clearances on controls etc. We fully support and encourage builders who want to build their own hoses. We offer an alternative solution in pre built and pressure tested hoses. All in all, the cost of an extremely high quality “build it yourself” hose system and the cost of our prefabricated hoses will be comparable. Everything we build is to certified or better quality but without the costs of certified assemblies.

Enjoy the build and if we can be of any service or if you have any questions please reach out to Tom or I.

Steve
 
Just leave it to Tom

I can not recommend the advise ,product and support offered by Tom at TS flightlines highly enough ...I have absolutely built my last hose! ....leave it up him and you will NOT go wrong
 
Last edited:
Correction

Realized my mistake. “Aircraft Specialty Flightlines” is the correct name for hoses. Worth their weight in gold.
 
Thanks Dwight---its all good. Aircraft Specialty, TS Flightlines, AS Flightlines, Aircraft Specialty Flighlines, All the same people, products, and services. Still maintaining some of the old indentities because thats how guys know us. Steve and I did consolidate 'most' of the fluidline production about 5 years ago to better serve all of you.
More products, kits and 'announcements' coming soon.

Tom
 
We are fortunate to have Tom and Steve as part of this community. Deal with them once and you’ll understand why.
 
Not happy with the per plans fuel valve to wing fuel lines that the previous builder of my RV-9A project installed, I removed them and I bought the braid covered conductive teflon fuel line and fittings to build new ones. Simple enough to fabricate using the compression olive sleeves, but overall I think for this part of the build, it adds a lot of unnecessary weight and a lot of stress at the up bend to connect to the fuel selector valve (Andair). I think I will make another run at it and pull them out and try the per plans aluminum lines again. If I am still not happy with those results, I will order the pre-bent hard/flexible combo fuel lines from Tom.
 
Hi David----the hose needs to bend in a shallow 90* and them left/right, and teflon really doesnt like it. Rubber will collapse, 701 hose cant bend tight enough to make the 2 shallow bends. Thats why we did the rigid tube/teflon hose solution. WE CNC bend a piece of 5052O tubing, after modifying it to accept the hose and crimp collar. You can do the same thing--sort off--by adding a sleeve and nut, then flaring the hose side and connect with a AN815-6D union.
I just felt that there was too many connections as well as the possibility of a bad flare that could pose an issue. You can do it with a hand bender, although it may take several attempts.

Tom
 
Hi David----the hose needs to bend in a shallow 90* and them left/right, and teflon really doesnt like it. Rubber will collapse, 701 hose cant bend tight enough to make the 2 shallow bends. Thats why we did the rigid tube/teflon hose solution. WE CNC bend a piece of 5052O tubing, after modifying it to accept the hose and crimp collar. You can do the same thing--sort off--by adding a sleeve and nut, then flaring the hose side and connect with a AN815-6D union.
I just felt that there was too many connections as well as the possibility of a bad flare that could pose an issue. You can do it with a hand bender, although it may take several attempts.

Tom

Thanks Tom for that info. I will try to get acceptable bends using the per-plans Versa-tube all the way out to the wing connection or just order the pre-bent set up you developed. I'm just trying to keep weight down and the setup I built weighs just too much with those heavy steel AN compression fittings and as you mentioned, that hose does not like making tight turns.
 
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