Poll: rigid tubes

[TS Flightlines]

Steve and I are doing some thinking on new product releases for 2017, and rigid tubes came up---again. With the success of our RV14 fuel system rigid tubes, we decided that offering a rigid tube option for some of our hose packages might be appealing to some builders.
A couple of thoughts were the 7A/9A cabin brake extension lines to the main gear bulkhead fittings, RV8 extension to the gear bulkheads, RV8 Andair valve wing lines, as well as our introduction of install packages for AFP pumps in RV7/9 aircraft.

So---I'll ask you, the builders, what would like to see? Our rigid tubes are generally 5052O, or 6061T6, and production items (like the RV14 tubes) are bent on a CNC bender. Prototypes are checked and tested, and then sent to beta testers for fit. (even then we still sometimes make changes). We realize that not all RV's are the same, but we think that for the most common items, we may be able to help you save time and aggravation.

Lets see how this works out--
Tom and Steve

[wjb]

Hi Tom,

Good question ... I'm working my way toward putting the gear on in a few months and was initially planning on asking you to make a set of flexible lines for my -7 from the firewall to the calipers, similar to the ones Vlad posted about a few weeks back (http://www.vansairforce.com/communit...d.php?t=142579)

Given that now there is a possibility for professionally formed rigid tubing as well as flex hose, what are the tradeoffs between the two? Price, weight, durability, ease of installation, etc.

Thanks for any thoughts, and I hope you're back to 100% after Matthew last week.

[TS Flightlines]

Bill---Not wanting to start a flame war about this,
aluminum tube that is well formed will last a long time. It is subject to vibration, and that movement can crack the flares at the caliper side. It is much less expensive than teflon hose and stainless hose ends. Maintenance can be a pain, because you are moving the tube around to do brake maintenance, work on wheel pants brackets, etc. Once you bend them, they hardly ever go back where you originally had them. But literally thousands of RV's and other experimentals have them installed, with long lives.
Hose---yep more expensive, but absorbs vibration much better, and because of that we typically dont wrap them around the axle. With the hose, you can completely remove the caliper from the axle, and not disconnect the fittings. You can move a hose around and put it where you want it.

There are pros and cons to both. We've been thinking about a possible combination of both, similar to some certified planes. But--we also want to keep costs down for the builders.

This is NOT a plug for using teflon hoses for brakes, but simply stating pros and cons.
Tom

[BillL]

I am about done building, and have no runs left to do, but I would have liked the idea of pre-bent tubing for runs, nicely bent/fitted with breaks for proper installation. I have always thought that tubes were more durable, lighter, and less expensive than hoses. Not to be used for everything obviously, hose has an undeniable function. One thing - kit stuff often is ill fitting and I often find it easier to do it myself than remake a more expensive part. So - if they are well designed, properly made and fit nicely (right down your alley), then it sounds like a winner, Tom.

One additional thing - having a good assortment of devices (or designs) for attachment would make the kits complete, nothing to invent.

Just my 2 cents.

[TS Flightlines]

Bill---we typically use several beta testers on things like this. But we've found that not all RV's are created equal, so the use of several beta testers gives us a good baseline. We know that builders will move some accessories around, so obviously those things have to be considered. Our plan is to make these according to plans built aircraft, that way we can produce a package that is correct for the majority of builders.

I big issue is access to the planes that are under construction to take measurements, and fine tune the prototypes. But we are working on a solution for that. LOL we even thought of building full scale mock ups of several of the cabins of various RV models, but that isnt practical for alot of reasons.

We want to make these kits as complete as we can with all the assorted fittings, clamps, grommets, bolts, etc as we can. That way it saves the builder time and effort to source these things.

Tom