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Fuel Lines & Brake Lines

mciaglia

Well Known Member
I am getting ready to tackle the brake and fuel lines. I know some people have upgraded to stainless steel lines from Bonaco / TS Flight etc..

Do most people just forget spending the time making the solid lines and order SS?

Is it better to spend the time fabricating the solid lines so they can be used to determine the lengths for the stainless steel?

Kinda exciting moving into something other than airframe assembly and working on systems.


Thanks in advance
 
Most people use the stock aluminum lines. They take 5-10 minutes each to fabricate and are identical to similar lines on many certified aircraft. They are also lighter and less expensive than the SS lines.

I suspect you'd spend almost as much time spec'ing out and ordering SS lines as you would spend making the stock ones.
 
I used rigid tubing in the cabin. For the fuel lines from firewall to tanks I followed the plans except I didn?t use the stock tubing?I upgraded to 5052.

For the brakes I used the stock tubing to the fuse fitting at the landing gear weldment. From there to the brakes outside the fuse I used SS braided line from TSflightlines and highly recommend them (both the company and the lines).
 
lines

5 -10 minutes for fabricating each line? You must have used the stock soft aluminum...

I opted for 5052 tubing in the tunnel. It took FAR longer than 10 minutes per line but then again the 5052 tubing is more rigid...

If I built another airplane, I would just have the SS hoses made. A whole lot less hassle and pretty much guaranteed not to leak.

That being said, I would give a great recommendation to Tom at TS Flightlines...
 
Mark -
I fabricated the lines per the Van's plans with the Van's provided tubing. It took a couple of attempts to get the fuel lines in the tunnel right, but I had enough tubing to do this. While it took a lot more than the 15 minutes another builder estimated, in the end they came out well and hopefully won't leak once I finish the build.

I figure I can always switch to pre-fabricated or flexible lines in the future if I have problems, so decided to start out per the plans. I've invested enough time and $ on other additions/changes to the base plans and figure I have to limit the changes if I want to complete the project.
 
+10^3

Tom at TS Flightlines was awesome as was his product. I'll get my fuel lines from him as well.
 
I am getting ready to tackle the brake and fuel lines. I know some people have upgraded to stainless steel lines from Bonaco / TS Flight etc..

Do most people just forget spending the time making the solid lines and order SS?

Is it better to spend the time fabricating the solid lines so they can be used to determine the lengths for the stainless steel?

Kinda exciting moving into something other than airframe assembly and working on systems.


Thanks in advance

Mark,

Congrats on getting to this point in your build. It seems like not that long ago that I was plumbing the cabin of our RV-10.

Tom and I have worked to put together drop in packages for the RV-10.

If you go to this page
http://aircraftspecialty.com/rv10products.html and click on

"Cabin Stainless Braided Brake Hose Kit", you will see images of the different cabin brake line packages as well as the pricing for some of the kits that Tom and I offer. There is no need to fabricate the lines first in Rigid if you are planning on using one of these kits, as we have all the dimensions worked out and ready to drop in for the RV-10.

The packages are all sold separately so that customers can purchase as many or as few hoses as they want.

As far as rigid fuel lines go...... the stock cabin lines are 3003 tubing, which is very soft and "relatively" easy to work with. I have an idea I would like to discuss with you. I sent you a PM on here, so please feel free to contact me at your convenience.

Happy Building,
Steve
 
I actually enjoyed making my hard lines. There’s something about it being challenging. When there done right they’ll last the lifetime of the airframe with nil maintenance.
I also opted for 5052 tubing.
They also weigh almost nothing too.
IMHO you’re less likely to mess up a hard line flare and fitting than doing flex terminations and I certainly think hardline flares are quicker.
But at the end of the day, for low pressure applications I don’t think this really matters tbh.

All that said… Tom did all my FWF and high pressure hoses including some bespoke problem solving and they definitely get the trophy for the best vendor to deal with in the entire build! Highly recommended, and if you decide for them to do it all then you won’t be disappointed.
 
Can you also make your own braided lines to save on cost??

Yes, materials to make your own lines are readily available. All the fuel, oil and brake lines (and their replacements) in my 1999 RV-6 were made in my shop and they have served well. However, the cost may surprise you, be sure you compare to ready-made lines before making the final decision.
 
Quite frankly I enjoyed fabricating the aluminum brake and fuel lines where ever possible. Where ever there was no interference installing them thats what I did. Like many others however, where ever there was going to be movement or significant routing interference I did flex SS braided from TS flightlines.
 
Like many I decided to fabricated all my own lines, some out of 5052 aluminum and many out of Teflon / SS. And while TS Flightlines is great, I wanted to make my own SS braided lines as they are easier to routes through bulkheads in smaller holes and then complete the end fitting (also no need for exact measurements and waiting for them in the mail hoping you measured properly). I used Earls Speed-Seal Teflon / SS braided lines with re-usable SS fittings. Simple to do yourself, but arguably no cost savings over TS Flightlines since the re-usable fittings are roughly double the cost of the crimped fittings that Tom uses. So aluminum tube for the short runs (easy to start over if you screw up a flare and most the cost of braided is in the fittings) and SS/Teflon for longer more complex runs and anywhere with vibration or the need for flexibility (gear legs).
 
Like many I decided to fabricated all my own lines, some out of 5052 aluminum and many out of Teflon / SS. And while TS Flightlines is great, I wanted to make my own SS braided lines as they are easier to routes through bulkheads in smaller holes and then complete the end fitting (also no need for exact measurements and waiting for them in the mail hoping you measured properly). I used Earls Speed-Seal Teflon / SS braided lines with re-usable SS fittings. Simple to do yourself, but arguably no cost savings over TS Flightlines since the re-usable fittings are roughly double the cost of the crimped fittings that Tom uses. So aluminum tube for the short runs (easy to start over if you screw up a flare and most the cost of braided is in the fittings) and SS/Teflon for longer more complex runs and anywhere with vibration or the need for flexibility (gear legs).
Ok, so what if you had some quality 'field installed' hose ends ( since a reusable hose end isnt really reusable other than the body and the socket--you have to have a supply of ferulles) and bulk teflon hose IF you wanted to make them yourself? Yes there are some custom applications were a field fabricated hose assembly might be easier than measuring and ordering. With RV's, almost all the data for common hose dimensions are known. That includes quite a few common custom accessories, like PMags, remote coolers, etc. But, since its experimental and alot of builder DO create their own systems possibly fabricating your own hose assemblies might interest you. We looked into this when we first got started, and were told by a very wise and influencial man that for the cost of pre-assembled and tested hoses it was worth his time and money to not have to do the fabricating, and have a wide selection of hose ends on hand. But, as others have said, they enjoy the process.
For us, the issue was a customer being able to proof test his assemblies, and the suppliers of quality field installed hose ends.

Tom
 
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I concur. I couldn't make a decent flare if my life depended on it, so I went with lines from Tom.
+1. Tom and his crew are fantastic. Peace of mind putting such a top notch products in my plane. Used them for both fuel and brakes.
 
Ok, so what if you had some quality 'field installed' hose ends ( since a reusable hose end isnt really reusable other than the body and the socket--you have to have a supply of ferulles) and bulk teflon hose IF you wanted to make them yourself? Yes there are some custom applications were a field fabricated hose assembly might be easier than measuring and ordering. With RV's, almost all the data for common hose dimensions are known. That includes quite a few common custom accessories, like PMags, remote coolers, etc. But, since its experimental and alot of builder DO create their own systems possibly fabricating your own hose assemblies might interest you. We looked into this when we first got started, and were told by a very wise and influencial man that for the cost of pre-assembled and tested hoses it was worth his time and money to not have to do the fabricating, and have a wide selection of hose ends on hand. But, as others have said, they enjoy the process.
For us, the issue was a customer being able to proof test his assemblies, and the suppliers of quality field installed hose ends.

Tom
You hit it on the head Tom, I wanted to build my own and enjoyed learning the skill in the process. Earls also sells a "test kit" (which is really just a bike pump valve and adaptor) to pressure test the lines to as much as a bike pump can do (more a leak check). If I hadn't needed wanted to learn the skillset of building my own then I would have used you. Still plan to use you for all the fire sleeve lines and -8 hose that Earl's doesn't sell. If your prices for field installed also beat out the speed seal cost then I would have gone that route as it would have allowed a reduced cost and learned the skill without risk of the lines being the wrong length due to my inability to properly measure (or not yet having the ability to measure due to parts not yet being assembled.
 
You hit it on the head Tom, I wanted to build my own and enjoyed learning the skill in the process. Earls also sells a "test kit" (which is really just a bike pump valve and adaptor) to pressure test the lines to as much as a bike pump can do (more a leak check). If I hadn't needed wanted to learn the skillset of building my own then I would have used you. Still plan to use you for all the fire sleeve lines and -8 hose that Earl's doesn't sell. If your prices for field installed also beat out the speed seal cost then I would have gone that route as it would have allowed a reduced cost and learned the skill without risk of the lines being the wrong length due to my inability to properly measure (or not yet having the ability to measure due to parts not yet being assembled.
Thank you Jon. A simple way of pressure testing the assembly is to use your air compressor. Use a quick coupler like Milton or others like your pneumatic rivet squeezer has. On the nipple side most are 1/4 male NPT, so get some AN 816 nipples and the corresponding NPT unions and reducing bushings to marry the parts together. Get some ANplugs to seal off the other side of the hose, then pressurize it. Submerge it under water and look for rapid bubbles from around the hose end sockets, and the nut area. You will get som bubble from under the braid, as the hose liner expands, it forces the air out, decreasing the longer the hose is submerged. Pretty soon all the bubble will disappear, provided the assembly is good. If you still have a steady stream of bubbles, then remove the air pressure and inspect the assembly to find out why.
We hydrostatically test ours, and during integration testing of our hose ends, we take then to alot higher pressure than you'll ever see in your plane.

AS for your other comment on the hose ends, I like to use a quote from Nichelle Nichols, LT, Uhura on the old Star Trek series. She once told a young officer, "Be careful what you wish for, you may get it." LOL
Tom
 

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