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New Fuel caps.

Zero4Zulu

Well Known Member
Finished up a couple custom fuel caps for My 6A.

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I designed these for easier removal and semi-tamper resistant. I don't have to use a pry bar to lift the lever. They have top flipper handle that pulls up easily, that starts the main lever coming up. Then you flip the main lever to relieve the O-ring pressure and the cap can be removed. I incorporated a locking feature that requires a 1/4 turn with a custom tool. Material is 6061Al. and 17-4 stainless steel.

Just another project I dreamed up for product ideas...
 
Wow, those look nice! Are you going to sell those or if not, share the design? I know of a few people who would love those as a replacement.
 
Those look great, the rest of your airplane must be outstanding.
Are these the older style caps? I would like to buy a couple like that for my RV8, If anybody makes them. Mine are the newer style that have a 1/4 turn to remove.
 
It appears these still expand the o-ring between two conical surfaces within the neck to secure them. Please clarify. If so, then Krytox will ensure they don't stick, ever.

Now the obvious . . . a beautiful design execution!! - The locking feature is clever and useful.

EDIT: Thanks for the update post on the action of the cap. The although the external friction of the handle contributes to the force required to latch, it does nothing for the release. The root cause of this cap design is the sticking of the wedge to the o-ring in the compressed state. As the cones draw together the o-ring must expand sliding between the cones. This means when full activated (expanded) the o-ring is stuck to the cones and this is the root cause failure mode for having to push on the pin to release the cap. Krytox is more than a fancy name. The key characteristic to Krytox demonstrated success is it's insolubility in gasoline. All other lubricants dissolve. EZTurn simply sticks.

This is no way detracts from the beauty, function and execution of your design! It is just not a solution for the primary root cause of sticking.
 
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Put me on the waitlist

Those look fantastic! If you do go to production I would be interested in a pair for my RV7. Looking forward to seeing pictures of your build and other custom feature craftsmanship.
 
These work the same way the Vans cap with the same O-rings and nylon tapered washers. One thing that makes these work so nicely is the little plate under the latch is heat treated hard 440 stainless so the friction between the two dissimilar materials is less.
 
A WORD OF CAUTION..........

There is no need to include "LL" on fueling placards. The requirement is to include "Minimum Fuel Grade and Quantity". The regulations say nothing about lead content. If you have "LL" on your fuel caps when 100LL goes away, you will need to replace your caps or placards.
 
I am in for three too! My girlfriend says I have a spare everything - except girlfriend.
 
These look great. Please put me on the list for a set as well, should you decide to produce them for sale. I'm not thrilled that I need a tool to pry open my gas caps whenever I want to fill up or even to just check the level. I'm assuming that your -6A caps will fit on my -9A...
 
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