Waiting for the moths to spin some silk. Spring?

"Dan Banjoks madness, a re-plumbed Tettra Tank-- the fuel is stored exterior to the blatter instead of inside the blatter. Air is sucked out of the blatter and capped, tank is filled full, feed line attached to the engine, blatter is uncapped and attached to muffler pressure. Tahh Dahh, no air bubbles, engine runs an excellent 4x2 break (La46) engine goes lean for two laps and shuts off."

Dennis, could you give me a few more details of the tank set-up?   
What is the "blatter" made from?
Any air entering the tank other than in the "blatter"?
GREAT looking plane and SUPER workmanship!
Thanks for sharing!   

"Tight lines!"

Wes

See they were all right,, we dropped the displacement limit and now all this hi tech profiles come out of the woodwork!
Looks pretty cool Randy, I still say a nice aluminum gear leg set would look totally sweet,, but hey what do I know,, I cant stay awake long enough to ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

Hi Randy.  So you want some inovative landing gear eh?  Well go here, http://www.brotherhoodofthering.info/flightline/forums/thread-view.asp?tid=1924&posts=20&start=1  and look at what Bill Gruby has designed for landing gear.  Wayyyyyy cool!

Hey Wes,

Thanks for the compliment about the Cardinal, but it was an ARF, I stripped the covering added the engine plates and fiberglassing. Wouldn't call that building. Do you mean Randy's plane?

The word is badder-- I misspelled the word, it isn't "blatter," sorry, I am spelling challenged often identifying words via sound. Also hard to think straight late at night or... when...

The bladder in Tettra Tank appears to be made of silicon. Tho I'm not positive. It is clear and flexible. The Tettra is a commercially available tank typically used in RC Pylon racing. As designed, the bladder is enclosed in a plastic tank, same as a clunk tank. The bladder is filled with fuel, expanding into the clunk tank space. Air is let out of the bladder, so that the bladder contains only fuel, no air, eliminating air bubbles which effect the fuel/air mixture going to the engine. Dan went to a Tettra Tanks to solve vibration/air bubble issues on a P40 ARF.  Weird vibrations are a frequent problem with profile models. The Tettra Tank worked fairly well, but the engine broke lean ten laps or so before the end of a flight. Too long a lean run. It appeared that the bladder did not collapse evenly causing a slight vacuum, making the engine run lean. To counteract this Dan tried storing the fuel exterior to the bladder, in the hard tank itself, same as one would do in a conventional clunk setup. The bladder was then used to expand into the tank as fuel is burnt off. Air is let into the bladder, not into the hard tank, so that air doesn't mix with unburned fuel.

Details of the plumbing have to wait. Dan hasn't draws them up. It's possible a magazine article will be published detailing the system Dan devised.

Glenn,

Yea, molded plywood gears are pretty cool. While I was sitting in a really boring meeting this morning (occupational hazard), I designed a gear that I think will work. I'll see about cutting a mold tonight. Big cool factor. Hey, if you're going to go this far out on a limb, might as well come up with something cool, right?

Boy Randy, great minds think alike.  When I am going through something BORING in school, I draw up stunters that I might design.  Basically brainstorming.

Don't worry, I still have good grades, A's and B's so my parents still let me fly these planes.

OK, so last night I dumped the landing gear, cleaned up the area and put in a new mount system. Then I made a plug for a new landing gear and coated it in epoxy. Tonight I will sand that down and start making a mold. Should make me happier. The original was starting to look like the gear for a 30s air racer with guy wires and such. Other that that, it's ready for final sanding and finish. I need to slip by the local screw place today to pick up the mounting bolts. I dont' have any long enough.

Rod,

Closer to a Werwage wing. Fairly thin airfoil with the high point back further than I usually do. A slightly thicker Novi airfoil.

Thanks Bill. I suspect I'll just mold up a CF gear, though using 1/64" plywood is intriguing. I have the plug finished but ran out of poop tonight. I will start on the mold box tomorrow. Should have it don't by the weekend. I just wasn't happy with the wire job. This wil work a lot better.

G-man, you need to refine that mold, it looks a bit rough,,
maybe make the next one from aluminum,,,,,,

An electric ducted fan Ringmaster? Wow, you really are out of control. My kind of guy.

 Out of control, I resemble that remark. You're gonna love this one.

  "Billy G"   

Well, I got the first leg out of the mold. Looks OK, though it will need a bit of cleanup. Trying to make molds when the temp is low is a challenge. but it's coming out OK in the end. First coat of dope on the fuselage.

Randy try Fastenal

Rod,

Went to Tacoma Screw and High Strength Bolt. No joy. I was able to order them from Micro-Fasteners, but had to get a box of 20. Oh well, I'll find some use for the extras. At least I was able to other some other stuff I was low on.

Bill,

Yea, pretty much. I changed the gear layout and ended up molding up two piece a CF job. This required a new mount on the fuse. The easiest way was to use plywood plates over the original hardwood mount. This makes the distance between the plates about an inch and a half. Add the thickness of the gear and 2" just makes it through with a bit over an 1/8" left. I wanted 1.75" of shoulder, but an inch and a half was all I could get. The layout is a bit weird. I hate retrofitting. Had I done this from scratch (or been willing to cut the entire area out and do it again - too much work), I would have gone about it differently. The whole operation sort of defeated the original purpose; to build the plane entirely (or almost entirely) out of the balsa scrap box and what I had laying around. Most of it is. Designing and building a new unit (the landing gear) was not on the agenda. Sigh...

Oh well, it's coming out OK in the end. I'm trying to decide, since I blew the original concept anyway, if I want to buy some Monokote or use the very old stock I have. Again, keeping with the original concept of using what I had laying around. We'll see.

Mark,

The stuff I have around is about 10 years old, but it's in unopened tubes and was in my closet all this time, not in the shop. But it's too late, I broke down and ordered some today. Decided I really liked the idea of transparent yellow.   

Which is why it won't be over silkspan.