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Cabin fuel lines and TSFlightlines (long)

sahrens

Well Known Member
After several attempts at fabricating really nice flares, I decided there needed to be a better way. I was concerned about the potential for a fuel leak due to my poor technique. Several folks have raved about the quality of the products and service from TS Flightlines. So I call Tom and we talked about building a set of internal cabin teflon fuel lines. Tom's comment was something to the effect of “If you can tell me what you want, I can make it.” He was true to his words. Although I did not do a very good job of giving Tom detailed descriptions of the lines I wanted, he somehow managed to make them anyway.

The process went something along the lines of; here is what I want, then would Tom made it. Then I would say, what I meant was..... and Tom would fix it. We shipped parts back and forth looking for the best radius on the steel lines and routing for the teflon lines. In the end Tom made three very, very nice fuel lines. Had I decided this before building the fuselage it would have been much easier to plan it out. In any event, here is Tom's excellent work. I can not recommend Tom enough. Quality work backed up by excellent customer service.

For clarity I am building a RV-7 with an O-360. The fuel valve is Andair.

Here are the lines connected to the valve
Fuel112_zps89632718.jpg


The right line passing through the attachment bracket on the center section
Fuel096_zpsea1ceb08.jpg


Routing of the right line to the tank
2fa58c1d-16e0-41d5-bef7-eac77cdd8108_zps5ba67c96.jpg
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With the cover in place
Fuel106_zpsf3c0364c.jpg


At the fuel pump
Fuel113_zpsd7d5774f.jpg


Tom did a great job.
 
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What about the landing gear weldments?

Won't the lines interfere with the installation of landing gear weldments?
 
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It is a 7, but if you can design it Tom can build it. I do not have the weldment, so I do not know how the routing would work. You would have that discussion with Tom
 
Those look amazing. I fought (and fought, and fought) with the aluminum lines on my -6A, especially around the weldments. This looks like a nice upgrade for me at the next condition inspection.

Thanks for sharing!
 
Another great job by TSFlightlines

Hey everybody, I just have to post this picture of the fuel line hoses that Tom made me. Inspired by the OP and his great looking connections I asked Tom to build me a similar set of hoses. Mine has the same bends as you can see in the picture below but the rest of the hose is flexible so it fits nicely through my A model gear weldments.

I have to say that Tom bent over backward to make these perfect and I think you will agree that he nailed it!

2014-03-27+17.51.53.jpg
 
Check for missing screws!!!!!!!!!!!!!!!!!!!!!

:eek: Scott: I'm looking at the photo of your Andair valve,I'm hope you haven't thrown the box out yet,as it looks like you haven't installed the screws for the tank inputs. These are in a bag in the box so that you can install at different angles if needed. I could be wrong and often am.
RHill
 
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:eek: Scott: I'm looking at the photo of your Andair valve,I'm hope you haven't thrown the box out yet,as it looks like you haven't installed the screws for the tank inputs. These are in a bag in the box so that you can install at different angles if needed. I could be wrong and often am.
RHill

Good catch RHill. I agree with your observation of Scott's valve. Darin's looks good, can't tell if the screws have been staked or not.

I would guess that Scott knows about this but these things are always worth pointing out.

Oh, and to keep this on topic, Tom's lines look great!
 
They are not missing

they are in the box. I put the fuel valve in the aircraft during the design and test fit of the lines Tom made for me. Everything is out of the aircraft and the fuel valve is back in the box with the screws.
 
they are in the box. I put the fuel valve in the aircraft during the design and test fit of the lines Tom made for me. Everything is out of the aircraft and the fuel valve is back in the box with the screws.

OK,Sorry "Mea culpa", went through my box and found the same thing.
RHill

Oh Yea, Tom the lines look great,I want a set for my 7a!
 
Actually Scott and Darin let the cat out the bag. YES---I'm going to do these as as a option kit to my standard hoses with 90*'s at the valve.
Understand---these arent easy to make, BUT---a certain partner of mine in Wisconsin acquired a NC mandrel bender, and yes I plan on putting him to work!
I have the patterns for these, as well as some other things, like the Andair tube that looks like an inverted question mark for connecting the selector valve to the Andair filter.
Tom
 
Filter or Gascolator

That was another question I have where do you put the filter or gascollator on this system? Walt suggests 70 micron before the pump, I'm thinking of a system with two collators in the wing root. Do these line kits extend to the tanks?How about custom hoses for the firewall side? Firewall to pump,pump to carb?
 
Yes the lines exit to the tanks. I'm working on wing root filter/hose packages for those that want filters at the wings.
Yes I have hose packages for the FWF stuff----but alot of it will be to your dimensions---because everyone doesnt put the same accessories in the same locations!!

Tom
 
Just curious what the green sticker on the spar says. Didn't have one on my spar, but the kit is from 2003.
 
Exit to tanks

Here are two photos that show the exit to the tanks. The line uses the same exit as the plans call for when fabricating the aluminum lines.

2fa58c1d-16e0-41d5-bef7-eac77cdd8108_zps5ba67c96.jpg
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f98933e5-34cc-4de8-a77b-69a784eafe52_zpse3173f2c.jpg
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The line I have running to the fuel pump could be changed for the filter prior to the pump, or installed after the pump. There is a fourth line I have to have Tom make that runs from the fuel pump to the firewall penetration point. I am not that far along but the filter could be there; although it would be after the fuel pump. Talk to Tom; if you can describe it he can make it.
 
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Just curious what the green sticker on the spar says. Didn't have one on my spar, but the kit is from 2003.

It just says that the spar was precision machined at the factory and the wing mounting holes should not be drilled or reamed.
 
I'm missing something here. What is the advantage of having the lines in the photos transition from solid tubing to the braided hose? Why not just stick with the flexible hose and an end fitting? Also I don't understand what's going on at the transition point from one to the other, near the brackets. There dont appear to be any fittings there.

When I did my -7A years ago I quickly grew frustrated trying to bend the tubing correctly and switched to the flex hose with fittings for everything, from end to end. Cost some $, but easy enough to fabricate each piece.

Thanks
Erich
 
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What is the advantage of having the lines in the photos transition from solid tubing to the braided hose?

I did it for two reasons. The first is my bending skills need help. Because of the gear mounts in my A model I found I had to bend the tubing in place with a spring bender which lead to poor bends and even gouges in the tubing. This looks way more professional and safe because the bends are perfect and the flexible hose allowed me to route it through the brackets, gear mounts, and then through the fuselage wall to the wing after the bends were in place.

The second reason was for stress relief. Flexible hose alone puts some stress on the valve fitting points initially as you flex the hose around to fit. I suppose that stress eventually lessens (not an engineer) but the first time I tried to put the flexible hose Tom made me (yes he made me two sets!) The amount of force I needed to get the hose around was significant.
 
Here is my reasoning

The first set of lines I had Tom make had more of the line as flexible. Here is the first set installed as a test fit. Notice the stress on the line as it passes through the opening.

73b739f9-207c-44c9-aa08-94769ce16f9d_zps69fcf117.jpg
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Here is a close up of the snap bushing. With that much stress something is going to wear out. First the snap bushing, but then the line and the aluminum bracket.

137e18e5-f475-4d4c-85df-37d3862b710b_zps3af58ebd.jpg
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This was my next idea to relieve the stress, open the pass through and sleeve the line. But you can still see the line is pressing against the bracket. It is a wear point I did not want to worry about.

0c23fec9-9f2e-42d7-b603-005610e6c5e0_zpsb62ea0a6.jpg
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So I fabricated an aluminum line for Tom to use as a mock up to make the bends on the steel line to eliminate the problem.

85948f93-a6de-44b0-8a46-cbdd81031de4_zps9b787262.jpg
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Scott
Can you explain how the transition from tubing to hose is constructed? Its partially visible in the first photo on post #1. I would expect an adapter fitting there but there doesn't seem to be one, at least nothing that I recognize
Thanks
erich
 
Actually Scott and Darin let the cat out the bag. YES---I'm going to do these as as a option kit to my standard hoses with 90*'s at the valve.
Understand---these arent easy to make, BUT---a certain partner of mine in Wisconsin acquired a NC mandrel bender, and yes I plan on putting him to work!
I have the patterns for these, as well as some other things, like the Andair tube that looks like an inverted question mark for connecting the selector valve to the Andair filter.
Tom

The cat is out of the bag. Right now these lines are being fabricated by hand. Tom and I are working on some really neat things which will involve the use of a computerized bender. However, it will be several months before it is all still operational. The bender has been acquired and we are currently waiting on some dies and flaring tools which are being custom manufactured for us.

We will also be utilizing some 3d scanning technology to ensure that we are able to fabricate these hard lines to perfectly fit in your aircraft.

We are really looking forward to this adventure and being able to bring some new and really exciting products to market. But, it will be a little while to get everything set up properly and running smoothly.

Steve
 
Erich---There is really no secret. I start with a piece of .065 wall .375 OD stainless tube. I cut it to the prescribed length, then mount the tube in the lathe and turn the collar lock groove, and reduce the OD to correspond to the -6 teflon hose. I then mark the bend centerline distances and make the bends. Presently, it is labor intensive, but when we get the NC bender operational, it will go faster.
Tom
 
What Tom said

Scott
Can you explain how the transition from tubing to hose is constructed? Its partially visible in the first photo on post #1. I would expect an adapter fitting there but there doesn't seem to be one, at least nothing that I recognize
Thanks
erich

The line is one piece at that point. I do not remember the PSI rating, but well above fuel pressure.
 
OK===since Steve mentioned it, I'll elaborate just a second on this.
The NC bender with CNC readouts has been acquired. This will allow us to bend rigid tubing consistantly and repeatively faster and more reliable than with current tools. As hose guys, we debated this for a long time, but eventually decided it was worth the effort. Lets face it, there are places where you just cant use a teflon hose either for dimensional or costs considerations.

With the bender, we can work off a prototype mockup, or from a 3D CAD file. We're very excited about this, and from the clients we have requesting some of these tubes, we feel its a great addition. WE are also working with a company to build us a powered flaring machine, to speed up the processes, AND to make quality parts.

Some of you figured out that I'm in South Carolina, and Steve is in Wisconsin, and were wondering how this is going to work. US TOOOO----I spend alot of time developing things like this, and will continue to do so. With the proposed 3D scanner, we can be in 2 different places and still accomplish what we need. Eventually, the goal is to be self-sufficient---to be able to provide even better service to all of you.
Tom
 
Tom and I talk daily. We both have the same customer service values and it is not uncommon to get an email from either of us at midnight. We are passionate about experimental airplanes and truly love doing this.

It's also been great being able to split up some of the R and D work to be able to bring even more items to market quicker. I have been working on a lot of the RV-12 packages as well as Zenith/Rans, etc. Tom has the knack of being able to attach any hose to anything else. There is just absolutely NOTHING that he can't figure out a way to do. We are going to be utilizing CNC technology to be able to adapt some of these projects onto a more of a "mass" production scale. In addition, with 3d technology growing, we are hoping to be able to utilize some of the modeling benefits to really improve our ability to visualize assemblies and how they will fit in the aircraft.

In addition, this will allow us to take a customer prototype and convert it to a model that we can replicate in a nice stainless steel rigid tube for your aircraft.

Finally, though we are split geographically, it creates a benefit for both of us as we are able to service customers most efficiently. And yes, we are still separate companies, BUT going forward we have been able to forge a great partnership/friendship that will allow us to bring unique items to market.

Steve
 
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