F-TWISTER UPDATE (with PIX)

Hello everyone,

And thanks for all the input! I am at the point now of details and finishing and final assembly. I will cover the wing with $-Kote and use 'rattle-can' paint since I have not moved up to a spray-gun.There have been many 'firsts' on this airplane and as I've said the inspiration has come from others on this forum. This is a kit-bash from from Bob Kruger's plans of 10/19/2003,revision #68.

PIX1) If you look closely you can see the 2 inch splice just aft of center of the tail-boom. I used the kit's 1/2 inch canopy block and cut it down for the 'Reno' fast-back look. With the riblets,the cheek cowl,enlarged flaps and stab/elevator this project involved enough 'scratch' building to make me confident I could build from just a set of plans!

PIX2) A better view of the in-board doubler.

PIX3) The business end! Ted's artcle call's for mounting the tank with double-sided sticky pads!? I like the idea,any comments? I will be using a'Perfect' style wedge uniflow on muffler pressure (Thanks Leonard). I used an idea from another post for the aluminum mounting pads and I love it! The pads mount with socket-head 4-40's and the engine sets on studs which are counter-sunk machine screws. This is set for a Randy Smith TT 36 but I can make pads for other engine bolt patterns and never drill into the airplane again. What a great idea! The hardwood dowel has a brass insert for the gear. I used the same thing for the aft 'weight box'(if needed). I threaded the insert for a 4-40 bolt if I have to add any tail weight. That idea was from someone kind enough to respond to my previous post; Thanks!

PIX4) Tom Morris' carbon fiber push-rod with ball-link and 3 1/2 inch phenolic bell-crank(not shown, obviously), smooth as silk! Another first. I mounted the crank using the Rabe 'BBQB' method shown on Bob's plans... very secure and elegant technique.

PIX5) Dacron hinges! Very floppy! Another first, almost.( I won't count the mess I made on a 'Shoestring' decades ago with Ambroid glue.)

All told, a great learning experience. If I could have all my wishes , I would finish the model in silkspan and use the Dacron hinges on the flaps. But I know my capabilities. I can get a decent looking airplane in the air soon. Regards to everyone and thanks again!

Sorry ,here is PIX4

Good job on the Fancherized Twister. I did one back in 2000 with the 3 inch extension in the rear fuselage with a Big Art Tower 40 and have enjoyed it immensely. Recently I blew up the plans by 116% and redid the fuselage profile to resemble Jimmie Leeward's Reno P-51 "Specter." I have 45 flights on it so far and it flys great too.
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Beautiful P-51,Tom! What are the black 'thingies' at the wing tips trailing edge?

LAST EDITED ON Oct-11-04 AT 03:11 PM (CDT)
 
On the original full scale mustang, they appear to be tip plates to stop span wise airflow. Go to the aircraft gallery on www.warbirdaeropress.com or http://www.aafo.com/gallery/history/leeward/ to see the full size ship.

Phil,
That looks great! Are you going to add a fixed fillet for the Flaps? So your elevator pushrod can clear your Flap? It's hard to tell from the Photo.

Keep up the good work!

That is all just a dry fit held up by masking tape. Tom Morris' control set-up uses a differential horn...I will work out the details when I complete the hinges for the flaps. I'm not sure what you mean by a "fixed fillet"?

The little fixed portion of the flap that is atached to the fuse and remains stationary.

That was pretty dumb on my part. All fillets are fixed in place. Except mine which are designed to shake off after two or three flights.

They help me to maintain my position in the beginners circle even though I've been doing this for thirty years

>PIX3) The business end! Ted's artcle call's for mounting the
>tank with double-sided sticky pads!? I like the idea,any
>comments? I will be using a'Perfect' style wedge uniflow on
>muffler pressure (Thanks Leonard). I used an idea from
>another post for the aluminum mounting pads and I love it!
>The pads mount with socket-head 4-40's and the engine sets
>on studs which are counter-sunk machine screws. This is set
>for a Randy Smith TT 36 but I can make pads for other engine
>bolt patterns and never drill into the airplane again. What
>a great idea! The hardwood dowel has a brass insert for the
>gear. I used the same thing for the aft 'weight box'(if
>needed). I threaded the insert for a 4-40 bolt if I have to
>add any tail weight. That idea was from someone kind enough
>to respond to my previous post; Thanks!
>

Just a comment (and it's visible in this picture). Do yourself a favor - round off that leading edge until you have approximately a constant radius from the top to bottom of the LE stock. It's *way* too sharp in general. It might be OK as is, but then again, it might not.

Thanks Brett. Thats one of the details I've still to do.

Nice Job...

For the tank, you have a great start--I did mine just like this.

I placed a couple of 1/8 wide by about 1/16 deep notches in the top and bottom edges of the tank mounting plate. THe notches locate two light Ty Wraps to hold the tank. Place some foam tape between the tank and the plate also.

Then, between the tank and plate, I placed a couple of fat short rubber bands flattened out. Put these right next to the adjusting studs.

THis gives quite a nice anti-vibration mount for the tank.

Set the tank at about 3/16" above engine center to start.

Kurt,

I have been using a similar tank mount. The difference between mine and the one you describe or the one Phil shows is that I included another piece of 1/8" ply, 3/8" by the width of the main mounting platform at each end on the fuselage side. This is slotted, too, of course, when the whole assembly is slotted. Two wire ties around the mount and the tank with some bits of foam tape twixt tank and mount make a clean and simple adjustable tank mount that works as well with RC "clunk" tanks as it does with the "Veco" (T-21X) or "Perfect" oval metal tanks readily available today.

The wire ties are much more reliable than rubber bands and are inexpensive enough to be removed (cut) and replaced to change tanks if needed or desired. Of course, this system requires none of the soldering that may cause beginners problems or experts the possibility of causing pinhole leaks.

LAST EDITED ON Oct-11-04 AT 10:33 PM (CDT)
 
Very Nice work. I hope I get to do one over the winter. Hope it turns out 1/2 as good.

Edit: I just looked at the photos again. I have a question about the landing gear. How did you mount them. It looks like a dowel glued in and then the gear mounted?

Paul

Paul.

This is a common modification to strengthen the split type gear that comes with the Twister and Banshee. When installed according to SIG's instructions, that gear is supported by the 5/32 OD tubing from the kit. That tubing is supported in the fuselage by the ply doublers and the balsa inside them. The doublers give are a great deal more rigid and supportive than the interior balsa. What this means is that the first time one lands the plane a bit hot or a bit roughly, the wheels exert force to the rear causing the tubing inside the softer balsa to bend forward and break. The dowel shown supports that tubing for its full length, thereby increasing the strength of the gear mounting system immensely.

That said, there is another way to strengthen the gear and remove a possible stress riser in the nose. That way is to extend the lower hardwood motor mount to the leading edge of the wing. Then drill that 5/32" hole for the tubing through the extended motor mount. BAM!! Instant support for the gear tubing and a stronger nose in one step.

Looks like you have lots of sanding to do. I'd suggest rounding off as much of the front cowling. I used brass brackets soldered to the sides of my gas tank, with about 1.5" high by 1/8th inch wide whole in the brackets so I could slide the tank up or down for adjustment. I used 4-40 bolts screwed into brass inserts to hold the tank to the fuse. This is one way to lighten the plane, I used your same tank mounting wooden mount on an old Tanager. It works , but I like the other way I just explaned that I used on my Cardinal. Not arf

Thanks Old Sourdough,
I am always learning here. That is what I like about this place.

BTW- The Stunt-chimp is still flying.. We nicknamed it "The Tank".

Paul