Summary

Hard lines are a great option for plumbing various fluids around a vehicle, due to their strength to weight ratio, as well as abrasion, heat and chemical resistance.
Pairing these with AN fittings suitable for motorsport use can take our plumbing to the next level. In this webinar we'll cover the different options we have with AN fittings on hard lines as well as some considerations when using hard lines our motorsport plumbing.

00:00 Hey team, Connor here from HPA and welcome along to this week's webinar.
00:04 So, this week we're going to be talking about motorsport plumbing, in particular working with hardlines and then working with AN fittings for hardlines.
00:14 So, we're gonna first cover the place of hardlines in motorsport applications and racecar builds and then we're going to move on and just discuss some general routing and fabrication considerations when working with hardlines and building them for your car, and then we're also going to cover the different options that you have when using AN fittings for hardlines.
00:38 So, just to get started, hardlines in motorsport applications.
00:42 So, hardlines are great for plumbing any of the various systems in a racecar.
00:51 So, that might be the fuel system, oil, braking clutch, power steering, coolant and so on.
00:58 Certain materials of hardlines are not suitable for each system, like aluminium hardlines for braking systems for example, we'll get into that a little bit more soon.
01:08 But generally speaking, hardlines can be used to plumb any of our systems.
01:13 Their main benefit is they have a great strength to weight ratio, so they're really strong and also quite lightweight and they have really good abrasion, heat and chemical resistance.
01:25 So, if we just jump onto my laptop screen here, we can see an example, so this is the SR20 VET engine out of our GT86 endurance racecar.
01:36 And we can see coming out of the turbo here we have hardlines for the oil and coolant in the turbo as well as other coolant lines along the front of the engine and so on here.
01:47 Originally these hardlines, sorry originally these lines here were all braided hose.
01:54 And basically with the engine bay temperatures, they were degrading or melting essentially.
02:06 We still have the drain out of the bottom here as a braided hose with insulation on it.
02:11 And also all this insulation added to the exhaust manifold and turbo as well.
02:17 But yeah, prompted to the move to these hardlines and since we've had those, they have been great.
02:25 One of the key things to kind of note here though is that even though the hardlines themselves have really high heat resistance, the fluid inside them naturally might not flow, that's something to consider and we still need to make use of heat shielding and insulation where possible.
02:48 Move onto some other examples here as well, this is copper nickel brake lines coming from the, I think it's a BMW E46 M3 ABS unit that has been fitted to our FJ40 project car.
03:08 And these here are the stainless brake lines that Brandon's just been fabricating for the refresh and installing the Bosch Motorsport ABS in the SR86 along down to this Perusic Engineering pedal box.
03:25 And there's also hardlines, this is the compressor for the paddle shift for the sequential Holinger gearbox.
03:32 Also has hardlines for the compressed air and then a little view of the back here.
03:37 Excuse the mess of everything, this is kind of mid refresh.
03:41 These are the hardlines for the air jacks, you can see the top of one here as well.
03:47 So, they're used quite a lot through our builds and we've had really good luck with them and used a lot throughout factory vehicles, normal road cars all the way through to high end motorsport builds.
04:04 So, one of the key things to consider with them, hardlines obviously don't allow for any flexibility.
04:12 Som, if we have components like the driveline, the engine, the driveline, and we are linking that up to something that's hard mounted to the chassis, the vibrations and relative movement between those cannot be allowed for generally in the hardlines.
04:29 So, that's where things like flexible hose come into play.
04:34 If we do use something like that where flexibility is needed, then it's quite likely that we're gonna break the hardline.
04:43 And that's gonna end up with leaks, cracks, leaks and possibly a lot more serious damage.
04:50 Sometimes as well another consideration around this is if you have a hardline going straight into a component and then we need to remove that component or the hardline for some reason, sometimes there's not enough flexibility in the hardline itself to undo that fitting.
05:07 So, in some cases, an example maybe here on the screen, you can see the top of the air jack there, and that needs to be adjusted so there's a flexible hose here.
05:19 So, you can still adjust the height of that and also obviously take that one off and easily remove that whereas if the hardline was going straight into the top, that would not be quite so possible.
05:30 Generally, in motorsport or automotive applications as well, there's three different types of hardline that we'll see, or sorry, four more likely.
05:39 I've got three of the options here though.
05:44 The first one that we generally see in most factory vehicles is just mild steel, regular steel hardlines, and these are often zinc plated or something like that.
05:55 They're great, they're strong and they tend to last quite a while, but they do not have the corrosion resistance so not only do they look pretty bad in the long run, but as the vehicle gets a lot older they obviously are subject to corrosion and tend to lose a lot of their strength as well.
06:18 So, generally when we're making new hardlines we have three options, I'll just jump under the overhead camera here.
06:24 These are the same size and one's just not by chance.
06:28 So, starting on this side here we have the aluminium and this case is dash six so suitable for something like a fuel line.
06:39 And then we have copper nickel which this one is 316 so dash three and that's suitable for something like a brake line.
06:50 And this is also a brake line in the same size, dash three and that is stainless steel.
06:54 So, between those three options, why would we choose one over the other? Well, aluminium is relatively strong, it's quite strong still depending on the application though, but it is extremely lightweight, relatively cheap and quite easy to work with.
07:14 The downside compared to these other two options is the strength so it's not really suitable for use in brake lines where the internal pressure is very very high.
07:25 Unless there's a significant increase in the wall thickness.
07:30 Moving up a step, we'll move actually to stainless steel.
07:35 So stainless steel is extremely strong and obviously really good corrosion resistance and chemical resistance as well.
07:45 The downside is it tends to be more expensive and it's also quite difficult to work with.
07:51 And then the other option here is copper nickel.
07:55 So, this is specifically an alloy for use in brake lines.
08:01 And in this case, so the main kind of advantage I guess of copper nickel over aluminium is the increase in strength, but it still retains quite good easy formability so it's still pretty easy to bend, flare and work with when fabricating lines.
08:22 It's a bit heavier than aluminium as well.
08:25 But it is not quite as strong as stainless steel and depending on your taste between these two, some people prefer this kind of gold or copper shade obviously of the copper nickel or some people kind of prefer the stainless steel look.
08:43 So yeah, a few different options but all of them generally speaking can be used all over the car except it's not recommended to use aluminium for brake lines due to the limited strength.
08:57 I'll just make a call that at any point throughout this webinar if you have a question, ask it in the chat and I'll do my best to answer it when I get to the end.
09:09 So, we'll just move on into some considerations when working with hard lines.
09:15 So, the first one I wanna talk about is just the routing and support of them.
09:21 So, support for one thing, this here is a little clip specifically, I think this one's actually designed to work with braided hose, dash six but it would work with a hard line as well so we can use things like this to support the hard lines, fix it to the chassis or other components with little clips like this and that just, yeah allowing that support means they can't be accidentally bent out of the way or get in the way of other components, and obviously we want to keep them well clear of moving components like drive shafts, engine fans, things like that.
10:04 The other consideration which we touched on before is avoiding heat sources.
10:08 So, like I said the hard lines will generally be able to take the heat in most cases but the fluids inside them will not and generally speaking, within reason, excessive heat for all of the plumbing systems in the vehicle results in some pretty negative effects.
10:28 So, that's something we want to avoid so if that just means we're running our routing to avoid the heat sources like the exhaust turbo manifold, in some cases the engine and coolant lines and things like that that are hot, that's best or if we really can't avoid them for some reason then using heat shielding or there's also insulation like special sleeves and wraps that we can put over the hard lines to just help cut down on that heat as well.
10:57 So, we'll just move into some more practical stuff.
11:02 We'll start out with the straightener.
11:06 So, this here is an Aeroflow straightener.
11:12 Which should probably be best on the main camera for this example.
11:15 So generally when we get hard lines, if they're aluminium or copper nickel, they quite likely come in a roll whereas the stainless often comes just in straight lengths because it is so much stiffer and harder to work with.
11:32 So, this is some dash six aluminium hard line that was used for fuel lines and it comes in a roll like this.
11:41 To be honest, this has been straightened and rolled back up a few times.
11:44 But one of the first steps is naturally going to be to straighten it out so we can get a good look of it and then make whatever bends and so forth that we need from there.
11:53 So, if I get this kind of roughly straightened out a little bit, won't be perfectly straight though, you can start to feed it into the straightener and this little knob on the top just adjusts the position of the top rollers relative to the bottom ones, and we can start to, it's not a very good setup here with the device not down on the table, start to work that through there and then slowly start to tighten up the rollers and you can see just from the basic work that I've done on that little straight section it just straightens it up nicely like that.
12:37 So, also if we ever need, make bends to a bit and then we want to, we've made a mistake and we need to straighten it back out, we can just use the straightener in that same method and come back and just straighten the part out to start again if we need to.
12:52 Speaking of bends, I'll just remove this out of here.
12:59 So, speaking of bends, if we are making just very slight bends to a part like it needs to follow a gentle curve, especially with aluminium it's quite easy to just make a slight bend in it with our hands and there's no problem with that, but if we do go and make sharp bends with our hand, if we just jump back over to the camera here, you can see in this case that that's just collapsed through the inside there.
13:32 If we make these by hand, and I'll just do it a bit more, that's quite stiff.
13:38 You can see that that's really kinked there.
13:41 So, if we did something like that and then put that in the car, that is not only a very weak point there where we've kind of permanently deformed the aluminium, and that would likely fatigue and crack and then leak over time but it's also clearly a restriction to the cross sectional area.
14:04 So, the flow would be restricted through there and we can possibly expect a pressure drop which can be an issue depending on what system we're working on.
14:16 So, rather than making significant bends by hand, it's best to use a tool.
14:24 So, I've got a few options here.
14:27 This is one of them.
14:30 Yeah I'll work with this part.
14:32 This here is just the most simple kind of hand bending tool.
14:36 So it's kind of like plier style.
14:39 And there's two different die sizes in here for different size lines.
14:43 And this is as simple as really just putting it in there and if we mark on this where we want the bend line to start, then it's just a matter of bending it around by hand like that.
14:57 And you can see there that that has just controlled that and given the material something to press up against so it won't kink in there and collapse the cross sectional area.
15:12 So, that's the most basic one and that works great for brake lines, especially if we want to make a bend in situ.
15:21 So, if we're working under the car in a tight space, this can be a really handy tool.
15:26 But probably the more, I guess better in some way option is to use something like this.
15:36 So this is a dedicated bending tool and it allows us to, basically it has this here which has the dies in it and then the lever arm as well, gives us a bit more leverage we can put on it and we can also measure the angle that we're bending about.
15:55 So, I'll just give an example again on this one here.
16:05 So, if we place this in and there we can see it's just in the first row, I'll show a bit better, this one here, that's the right size for this material and then place it up on the stop like that and then we can, bit tricky with one hand trying to show it under the camera.
16:37 Line up the zero marks like that and then in one swoop we just want to bring this around so that zero lines up with the 90 and around like that, and pretty simple.
16:53 Then we just have that 90 degree bent.
16:56 That looks like it's maybe, it's about 90, a little bit less than 90 degrees maybe.
17:01 The other thing that we can do with this here, so what it allows for with these marks is basically, or naturally if we bring this around we can do different angles but it also allows us to measure I guess the distance of the material that's taken up by the bend, so I'll just give an example of what I mean there.
17:28 I'll come back to that in a moment.
17:30 So, let's say we have a bend, do I have a pen here? And we've mapped out our part and we want to work across the bend.
17:44 So basically what I mean is we want the part, the end of the part to be here and that's where our fitting's going to be and then this will come up and then we want it to bend like that.
17:56 And we want the distance from here to here to be let's say 100 millimetres.
18:06 So, this part will allow us to measure or get that correct, we're taking into account how much material is used up there.
18:14 So, for example I'll try to bend this stainless, bit of stainless that we've got here, so what we can do is we can get our roller and measure it from the end of that to 100 millimetres.
18:36 Then what we want to do in this case is put that back in, line up the zero marks and then line up that with the L and what the L means is that we're measuring from the left end of the part and I'll explain the R in just a moment.
19:01 And then if we bend around here, you can see it's quite a lot more difficult with the stainless.
19:13 Then the distance across the part there, I underbent that a little bit but you can see that ends up being about 100 millimetres there.
19:21 In some cases these tools will bend that to the 100 millimetres to the centre line, our centre point there or it'll be the centre line of the tube across the bend from end to end.
19:39 So, where we use the R is essentially if we're measuring 100 millimetres, say from the other end of the tube, then we'd come in and we'd line it up again and line that up with the R there.
19:57 So, that means right side or some people, the right side of the tube or some people call that a reverse bend as well.
20:04 And then there's a little other mark here and that is the same thing, but for a 45 degree bend.
20:11 So, we line up the point of the tube with that mark, line up the zeros again and then bend around again until the zero gets to the 45 but that will give us the distance across the bend to the centre of the tube if we line it up with that one for a 45 degree bend.
20:30 It's one of those things that doing it yourself a few times, it starts to make a bit more sense than just watching someone or explaining it.
20:42 So, moving on, these two kind of, depends what process you're working in but you may bend or you may cut first.
20:54 So, the way that we generally cut these is with this tool here which is a pipe cutter.
21:00 So, basically this has just got a blade on a wheel there are opposite two rollers and we can adjust the distance between the blade and the rollers.
21:12 So, for example tighten those up there and then once that's snug start to wind it around the tube, the pipe, brake tube I guess, slowly tightening it up, a bit more each time.
21:34 And eventually it will cut through.
21:47 Like that, so it makes quite a clean square cut.
21:51 If we do notice there's any burring on the end of this, we obviously want to get rid of that before we do any flaring or anything.
22:00 We can use a file just to straighten that off if we need to, clamp this in a vice and use a file or you can also use a little deburring tool like this just to take that off.
22:11 But obviously you need to be careful depending on what system you're working on that if there is any metal shavings that get inside the tube that you just blow that out with some compressed air because we don't want those metal shavings then going and getting into our brake calipers for example.
22:33 Another process that we should just mention is if you are mapping out hard lines then using something like this which is just welding wire as a test piece can be really beneficial.
22:47 You can bend that into the shapes that you want just to plan it out and then also it's possible to mark this and bend it with the same tool so we can get the radiuses the same and then it's possible to compare that to this here and basically take the template to the real piece, and make sure that we get it all right with the cheap welding wire first before using something like our actual stainless brake line for example.
23:26 So, the final thing I'll just show is specifically for brake lines in this case, before moving on to the AN stuff, is flaring the end of the brake line with the use of a tube nut so we can screw that into whatever other brake fittings that we have in our system.
23:49 There's, I'll show this one here first, there's two kind of main different options when it comes to brake system, brake flaring tools or flaring hard lines in general.
24:05 This one here is probably the more basic one so basically we just have some different dies and tools here and then this clamps it in place and then we use this here to flare the part but generally speaking that does work but it isn't as good as the other option which I'll show now.
24:28 This is probably a little bit easier to use, this kit does come with a bit more expense, but from my experience of using it compared to that other one, this here results in a much better seal every time and I've never had an issue with this one breaking.
24:49 So, this is what I'd call kind of like a professional brake flaring kit.
24:53 And it uses a turret, some people refer to it as a turret brake flaring tool.
25:03 That will make a bit more sense in just a moment, get this in the vice.
25:13 So what we do here is we have some different dies and we choose the one that we want.
25:21 So in this case it's gonna be for 3/16 and the DIN flare.
25:30 45 degree, sorry.
25:33 So, for brake lines using a 45 degree or double inverted flare, we use this one here so you probably can't quite see that on the top, it's got 3/16 or 4.75 mm, which is the metric equivalent and 45 degrees here.
25:50 So, if we just undo that, push this over a bit.
25:58 And we can stick that in there and then it's just a matter of with the tube nut slid on first because if we already have a bend in the line like this and then we do the flare, we won't be able to slide the tube nut on and we'll have to cut the end off again.
26:14 In that case, we might need to remake the whole piece.
26:17 So, slide that on.
26:20 And put this on again that way.
26:25 So, basically the tube sits in there, we can slide that across and we use this zero operation, sorry I just need to grab the lever arm, which goes in the tool.
26:42 This vice is not the best setup.
26:47 So, operation zero, you probably can't quite read that, the little yellow arrow just allows us to pull that along and just make sure that the tube is flush with the end of the die there.
27:04 And then slide that through there.
27:10 And tighten this up to lock the tube in.
27:15 And then the double flare that we're gonna use has two operations; so operation one for 3/16s, we bring this around and we just pull back on this.
27:35 Bit tricky in this vice setup here, might actually not be able to do it, because the vise will move.
27:51 And then from there you pull around to operation two, 3/16s and that completes the flare.
28:02 Bit tricky when I'm trying to hold the vise with the other hand.
28:06 See if it worked.
28:10 Pull that out, that didn't really work properly but regardless you get the idea.
28:16 And then this would be able to tighten up and pull that flare against the other seat.
28:23 So, again make a call for questions if you do have any.
28:28 Feel free to ask them, and I'll do my best to get to them at the end.
28:33 But we'll move onto the different types of AN fittings that we can use with hardlines.
28:39 So, the key difference we just talked about with brake lines, use a 45 degree double flare.
28:46 So, that means the flare surface is 45 degree and that is the surface that creates the seal.
28:53 AN fittings, AN standing for Army Navy, which is the standard for the fittings, use a 37 degree flare; and a 45 degree and a 37 degree flare if they are mating surfaces obviously isn't gonna create a flare.
29:09 So, there's two different, two main different types of AN fittings that we can use with hardlines.
29:20 So, let's look at the hardline again as well.
29:28 This first one I'm gonna show is, oh where did it go, there sorry, is what we, when we flare the end of the hardline, this is what we use.
29:40 So this here is the fitting that has the tube nut and the tube sleeve.
29:46 So basically, grab the other tool here, we want to slide these on first.
29:56 So we'll slide on the fitting and then the tube sleeve.
30:02 And then we can use this here under the overhead, which is rigid, 37 degree, it says on there, you might be able to see, probably not quite in the right light.
30:19 And then we want to use the right die in that case.
30:27 This might not be, this might be easier for me to do out here rather than under the overhead because space is kind of limited.
30:34 So, we want to put the tube in the 3/8ths in this case which is dash 6 hole and line it up with the top surface there so it's flush, and then move this into place and tighten that up over the top of that there.
30:59 Oh, it slipped.
31:09 Once that's in place, then it's just a matter of using this and winding down on there to create the flare.
31:19 It can be quite hard on this one even with the aluminium.
31:35 Wind it down and this one actually has a kind of torque sensing thing that should click when it gets tight.
31:47 Back this off.
31:49 Sorry, doing it behind my laptop.
31:58 Wind that out, undo that.
32:21 You can see that that has made the flare on the end there and then the tube nut would come up and the sleeve probably, yep, I went too far with it.
32:33 And then this should basically fit in there.
32:36 Oh, sorry, I'm not showing it very well.
32:38 Fit in there and then thread in but I over flared that so the tube sleeve can't go too far.
32:49 The other option is what's called a compression fitting.
33:01 So, I've got two options here, both from Raceworks and they're basically the same except one has a 90 degree angle on it.
33:14 So, we'll just put this aside for now.
33:18 So, this is the part here and it's made up of three different parts.
33:22 So, the fitting side there, the socket and then also the important part here is this olive.
33:30 So, if we get this part here, basically it's pretty simple from here, the end of that's not in very good shape but be alright for this demo.
33:43 Slide that over there and we slide the olive over as well.
33:49 If it will go there over the end and then this part here has a little internal step on it and that will come on and sit flush with the end, and then it's just a matter of doing that up and the compression on that olive will create the seal and then we just have that as a male AN on the end here, but it's also possible to get these that turn it into a female part as well.
34:27 That's called a compression fitting or also a hardline to AN adapter is the other option, the other name for it.
34:36 So yeah, I'll just leave it there, hopefully that has shown a few options that you have when working on hardlines and using AN fittings.
34:45 I'll just jump over to my laptop in case there's any questions.
34:57 So, Seagull260 has said "What considerations should be taken when mixing different metals for the hardlines and the fittings, i.e. stainless hardline with an aluminium fitting?".
35:09 Yeah, that's a good question.
35:10 So, when we have contact of dissimilar metals, the different electrode potential in them will result in what's called galvanic corrosion; so basically one of the metals will corrode quicker than the other one.
35:27 In the case of the aluminium and stainless, I think the aluminium would corrode a lot faster.
35:33 So, it's not an issue for the stainless, these fittings are anodised so generally they are safe to use in this case and there shouldn't be any issues with corrosion.
35:47 But if you do have, for some reason, a stainless hardline in contact with a flare surface that doesn't have a coating, that's just something that we need to avoid and that's something that we need to think about all over our racecar builds is trying to avoid that contact of dissimilar metals and when we do have them then they need to have coatings on them to avoid that.
36:14 And if we don't then it's just something that we need to keep an eye on and maybe increase the service interval or just make sure that it's not corroding or accept that it's going to need to be replaced more often.
36:33 So, Sergio said "Best lines and fittings for air like those used for ARB air lockers.".
36:40 So, I haven't done any work with air lockers but if we look at this compressed air, this is the compressed air for the Holinger sequential paddle shift in the SR86, and Brandon has used the flare type fittings that we just showed before so it has, you flare the end of the aluminium hardline and then use that with the tube sleeve and tube nut onto the AN fitting, and that works great in that case and we also have our air jacks, we'll just put a photo of that here, and they look to be plumbed with the same type of fittings there.
37:22 Rather than a compression fitting in that case he's used a flare with a tube sleeve and a tube nut and that's all aluminium as well so I don't know if there's any pressure difference between the operating pressure that these systems work at for the air lockers, but I'd assume something like that would be suitable.
37:50 So, Sorbe, Sorbe, sorry, if I'm butchering that, "Did you use aluminium or stainless hardlines on the turbo lines for the SR86? Does the harmonics of the engine create issues if you use aluminium?".
38:05 So, we used aluminium and there hasn't been any issues with them.
38:11 I guess you're talking about vibrations from the engine and then that leading to fatigue with the aluminium and cracking, hasn't been any issues with it.
38:22 And it is a four cylinder, that revs pretty high so if it was gonna have issues it could do.
38:30 I think because it's hard mounted to the engine and there's not too much relative movement, even just with the vibration of the engine it's not an issue in this case.
38:40 So yeah, aluminium has been on there for maybe two or three seasons now and there hasn't been any problem with the vibration or with things expanding and moving with heat either.
39:08 Figure at Audi says, "Is it a given that you should not convert a connection to a hardline if the two points of contact, i.e. where the line is coming from and going to a connected part, connecting parts that move independently? Example, if you're connecting a coolant line from the block to some other location on the chassis, a bad idea? Or are there fittings that can flex or otherwise compensate for this movement?".
39:36 So yeah, we talk about that a little bit in our plumbing course.
39:39 There are fittings like pipe clamps, be it Wiggins pipe clamps or something like the Plasma Man plasma clamp or Vibrance HD clamp that allow for a certain amount of axial movement, and also angular movement as well to allow for what you're talking about.
40:01 It depends on the car, the engine, the stiffness of the engine mounts and things like that, whether it is enough.
40:10 The SR86 has Wiggins clamps on the coolant lines between the engine and the chassis, but they're also braided hose so that's not an issue.
40:23 But on the intercooler lines I think it has Plasma Man plasma clamps.
40:27 And there hasn't been any issues there either.
40:30 So, those are definitely options to get around that.
40:35 And yeah it depends on the car and the application, but those are the options.
40:40 So, it's pipe clamps that allow for some slip and movement.
40:48 Is a compression fitting appropriate for most, sorry GW2 asks, "Is a compression fitting appropriate for most automotive line pressures?".
40:57 Yes.
40:59 So, I've used them on my own car with fuel lines.
41:02 I'm not sure about using them on brake lines, those would usually use a pipe, a tube nut and a flared surface.
41:16 But brake lines can see north of 1000 psi, we have fuel systems only working at 40 to 50 or so.
41:27 So, I'd probably say, not off the top of my head I don't know the actual rating for these compression fittings.
41:35 But yeah I probably wouldn't use them in something like the brake system.
41:39 But they seem to be fine in most other systems.
41:44 But yeah might need to do a little bit more research into that one.
41:59 So, Matt B said "Are AN-3 fitting flares suitable for brake lines or are the OM style double flares always required?".
42:09 For brake lines you really need to use a 45 degree double flare or a bubble flare is often used on European cars.
42:19 And they're much more, have a much higher integrity in the flared surface and the seal as well, they're a lot stronger.
42:26 Yeah, you really shouldn't be using AN-3 flares for brake lines on hard lines anyway, there's some different uses for the AN-3.
42:38 You could be using a flexible hose, but you have a crimped fitting.
42:43 But they need to be then pressure tested to ensure that they're up to scratch.
42:48 In certain parts of the world, depending on if you're using the car for road use, it's not legal to have anything else other than the 45 degree double or a bubble flare.
43:00 So, I'd definitely recommend that.
43:08 Roger Wilcox, "On the aluminium dash six line for fuel, is there a preference for reliability using the compression fitting or the flared fitting?".
43:17 So, in my experience I find that using the compression fitting is a lot easier and you have this machined surface for the flare.
43:28 So, the actual flare itself I find is like a machined part and that'll match with the corresponding female side and I don't really have any problems with that.
43:42 And then whereas if you flare it yourself like I just failed to do just before, then there's more chance in my mind that that will be an issue.
43:55 Depending on what flare tool you have obviously.
43:59 So, I personally prefer using the compression fittings, but someone who's worked a lot with flare tools and is really comfortable doing that might prefer it the other way.
44:11 Yeah in my mind having the machined surface of the male part and the female part is going to create a better flare and they're pretty easy to use with that compression.
44:22 You just need to make sure the olive that you're using is in good condition and the end of the tube that you're connecting is nicely, cleanly cut with no burrs or anything like that.
44:39 So, Sergio Gutierrez Jr, "When considering aluminium, how thick of a sidewall can you go before just moving onto something stronger like stainless?".
44:50 So, aluminium I think is about a quarter of the density of stainless steel or just steel.
45:00 So, that gives you an idea of if you're increasing the wall thickness of aluminium so much to make up for that strength then yeah you'll get to a point where you might as well have just used stainless.
45:19 I don't have a number off the top of my head though of working that out, it would take a little bit of a calculation with finding the volume of the pipe and using the density and so on.
45:30 That's gonna be different depending on the internal diameter as well.
45:34 Because if you imagine as you increase the diameter, the wall thickness becomes only less of a fraction of that total volume I guess.
45:45 But yeah, if we just consider that it's about, I think it's a quarter of the density of steel then that will give you some idea anyway.
45:57 So yeah, that looks like all the questions.
46:01 If there is any other plumbing topics you wish for us to cover in webinars like this in the future, then feel free to leave a comment and we'll do our best to get to that in the future.
46:13 But I'll leave it there for now, so thanks for watching and we'll see you next week.