There's gotta be a better way: fuel tanks.

[rvbuilder2002]

Originally Posted by Jim T

Sorry Scott..........didn't mean to push your button.

You didn't "push my button" at all Jim.
I am just talking facts rather than opinion (the reason the last line says "I am confident that no one is likely to find a different construction method that will be as light or for anywhere close to the same cost.......")

It is a viable and likely optimal way to do it if weight and cost are important engineering goals.

If those aren't goals (in an airplane like the RV-12 the first one is a very high priority), there are a lot of other ways a tank could be produced.

[Canadian_JOY]

Just a data point to add to this discussion...

Glasair supplies welded tanks for the Sportsman. There is a service bulletin from the early days when some of the welds were porous. Since that small batch of tanks which contained what amounts to a manufacturer's defect, there have been no significant issues with fuel tanks.

By the same token, Stoddard-Hamilton also shipped some plastic moulded tanks for the Glastar. They quickly became pretty famous for leaks which were resolved only by replacing the tanks with the welded aluminum ones.

Zenith also provides welded tanks for aircraft like the CH750.

While the Vans standard method is a good method of fabricating tanks, a search on this forum will reveal multiple threads talking about leaking tanks. As was mentioned earlier, every design/build decision is an exercise in balancing compromises. One needs to be happy with the compromises Van and team have chosen.

[Jim T]

Originally Posted by rvbuilder2002

You didn't "push my button" at all Jim.
I am just talking facts rather than opinion (the reason the last line says "I am confident that no one is likely to find a different construction method that will be as light or for anywhere close to the same cost.......")

It is a viable and likely optimal way to do it if weight and cost are important engineering goals.

If those aren't goals (in an airplane like the RV-12 the first one is a very high priority), there are a lot of other ways a tank could be produced.

We're definitely on the same page Scott. I can't believe how light my tank is and as expensive as a welded tank would be, I'd rather build mine like I did. Plus, if I built it, I can also fix it if needed. My neighbor is building a Rans S-20 and both of his plastic tanks have had leaks.

"Crude" probably wasn't the best way to describe the tank construction ..........I just couldn't think of another word to use at the time.

Jim

[Tomcat RV4]

Any body coated tanks with clear epoxy ? It was suggested by tech counseled with -6 ? Seriously çonsidering , as it would be paintable, and not affected by fuel !

[Canadian_JOY]

Derakane vinyl-ester epoxy (used in Glasair fuselages) has excellent characteristics for fuel tanks. In fact it is used to fabricate fuel storage tanks in the petroleum industry. It obviously has decent structural characteristics as well, since it has successfully been used in the construction of quite a few aircraft. It responds best to vacuum bagging as air-cured Derakane never really cures and remains slightly "gummy" to the touch.