Tank for Cox .049?

I've decided that maybe the best starter plane for my kids is the Osborne platter: cheap, easy to build, and danged near indestructible over grass. Problem is Cox .049 availability. But, I see that they're still selling their "sure start" .049 for $7. Not bad! But, I need a tank. It's been long enough that I don't recall what size is most appropriate for an .049. Would 1 oz capacity be about right?

Suggestions welcome!

Kim

Many use balloon tanks for smaller engines, and may offer some suggestions here.

This link is to an old thread, with detailed balloon tank building instructions from Ray, the Minnesotamodeler. Scroll down to find reply #8.

There is also a link to a shop with a list of available Brodak tanks in another message. See reply #1.

Bill

Email Ray Stone, aka "MinnesotaModeler". He has a very nice kit for a Minnie Delta that makes an excellent trainer.

Also contact Ray and Larry Renger, aka "DesignMan", as they have each developed a simplified balloon tank system for the Cox Shur-Starts and other ½A engines lacking a tank.

>been long enough that I don't recall what size is most
>appropriate for an .049. Would 1 oz capacity be about right?
>
For a trainer a 1 oz tank would probably be way too big. Need to aim for about 2 minutes to begin with which will probably be enough for both the instructor and student. The Cox PT-19 only has a 1/4 oz tank with a provision for short tanking. My recommendation would be 1/2 or less capacity. It is hard to short tank less than half the capacity of the tank.


Carl

Kim,

I have never built the Osborne Platter, but since you are using a tankless engine, I would extend the mount to place the engine in the original position for balance.

Good luck with it. I would use a 1 oz. tank and let nature limit the flight.

George

My favorite tank for an 049 is a 35mm plastic film cannister. Go somewhere that they do one hour processing and ask for any that have the lid that snaps into place with an internal seal (not over the top like a jar lid). Then just drill in the lid near the edge a slightly undersize hole for small fuel tubing and push it through the lid. Another hole for the overflow is a minumum. Two holes makes fueling easier. The tank is a bit big but you do not have to fill it all the way.
Bob Furr

"See ya in the circle!"

Cox Sure Start engines are plentiful on eBay along with the plastic tanks made for these engines. I'm not sure on the size but they simply press-on to the fuel inlet. Looks like maybe 1/2 oz. or 2/3 oz.?

[photo not recovered: 29452.jpg]

Attachment #1, (jpg file)

Doug,

I have never seen one of these tanks before. Does it come from a plastic RTF?

George

>Doug,
>
>I have never seen one of these tanks before. Does it come from
>a plastic RTF?
>
>George

Came on the freeflight helicopter there was a .049 and .020 size. It is designed to spin with the engine during run, fuel pickup is in the wedge opposite tube. All I saw had an engine run of less than a minute. Helicopter went straight up while engine ran after engine shut off auto-rotated to a semi crash landing with frequent damage to the landing skids. Should work on CL if oriented correctly.

Carl

Won't an old Babe Bee tank assy. interchange also?

>Won't an old Babe Bee tank assy. interchange also?

Yes it will, along with the backplate carrying the needle valve.

1/2 oz. is plenty, you'll get up to 3 minutes, maybe more depending on how lean you run it. For a beginning pilot that is a long flight.

The "floppy balloon" tanks do indeed work very well with these engines. Turn the backplate so the needle extends to the inboard, fuel pickup to outboard. Protects the needle and presents better access for refueling.


[photo not recovered: 29458.jpg]


[photo not recovered: 29459.jpg]


[photo not recovered: 29460.jpg]


[photo not recovered: 29461.jpg]

Attachment #1, (jpg file)
Attachment #2, (jpg file)
Attachment #3, (jpg file)
Attachment #4, (jpg file)

Yup, that's exactly how I had to mount my engine for best fuel feed with side-mounted cyl. Tank is 2/3 oz.

[photo not recovered: 29468.jpg]

Attachment #1, (jpg file)

All these responses have been great! They've given me lots of ideas to act on. Thanks to you all!

Kim

>Yup, that's exactly how I had to mount my engine for best
>fuel feed with side-mounted cyl. Tank is 2/3 oz.
>
>[photo not recovered: 29468.jpg]
>

I like your color-coordinated rubber band.


[photo not recovered: 29475.jpg]

Attachment #1, (jpg file)