Originally Posted by Freddie B

That would be awsome, and no need to support HK when you can make your own! This thread is back to being exciting again! With Hawk, Rimshot, SNice, and Edwen all leading the activity......(Now the pressure is off....)

Fred

Exactly agree with "no need to support HK", well, mostly... Except I do buy most of my electronics from HK, even most of my batteries. Something next in my bash list would be like...
F-15 or/and F-18 (both will be pusher jet),
some Israeli fighter jets like Kfir,
or even Rafale...

I do have extra pair of wing from one of the Titan glider, maybe a Northrop flying wing: http://www.richard-seaman.com/Aircra...FlyingWing.jpg


Already got some Depron and Blucor in the garage, looking forward to more warbirds, or even some 3D plane conversion.

Yup, Rimshot - I think you may be onto something fantastic with the V-tail conversion! Here's a few reasons why:

1- unobstructed inlet/outet - so you can maximize thrust.
2- should be easy to balance
3- thrustline will be close to centerline of model so proper thrust angle should not be too hard to determine.
4- Tail is already oversized so perfect for v-tail

The V-tail solvesthe issue I had with my first EDF conversion -- the Rudder was in the way!

Think you may have yourself a winner!!!

Don't know about the expanding foam -- I thought that stuff was very heavy but if others are using it with success,then it is worth looking into. Personally I would attach the Edf housing with Gorilla Glue - and clean it up using lightweight spackle.

I agree about the attachment however there are some large gaps from the modification to create the V-tail. I need something to fill these gaps. Any ideas?

Edited: I could tape over them, but I wanted to do a good job.

Originally Posted by Freddie B

... BTW, is there a bit of sarcasim in the "my models now take 3 times as long" and "Now I too need a vacuum forming table "-- remarks?

Thanks, Freddie B! Nope -- no sarcasm at all! I should have been in the air with the 70mm T-bird model 2 weeks ago! The finishing, and sanding, and painting are what has been holding me up! All of which I learned from you! Once I put on your "Secret Sauce" (which isn't so secret) - the model has bocome so smooth - doesn't look like foam anymore. My sons are well out of the baby stage but I'm still in the baby aisle picking up talcum based baby powder - and boy do my models smell great! ...Then I had to have nice decals to match the finish - so I had to find images and alter them on the computer so I could print them out...I also went out and bought an airbrush with a 50%off coupon from Michaels!!! I still need to get a compressor though - they were a bit "pricey-er" than expected -- so I used paintbrushes and acryllic pens for the trim.

Now... I've been on the lookout for plastic bottles - so I can add a "glass" canopy... If I made your vac table, this would not be an issue at all!

Your methods, and countless others as well, have definitely taken my scratchbuilds to the next level. This is by far one of the best learning communities I have ever been a part of. I've gotten soooo much from these boards that I am always eager to give back...it's just delayed a bit now because it takes me forever to "finish" a model!

Baby Powder? Please tell!!!

Originally Posted by rimshotcopter

Baby Powder? Please tell!!!

Rim,

I'm with you. I don't know the secret handshake yet. LOL

Freddie B- After maiden of the "A" model airliner, the pressure will be back on !

As soon as the wind drops to 10 or below, I'm on the field.

-Hawk

Originally Posted by SNice

...
... so I had to find images and alter them on the computer so I could print them out...I also went out and bought an airbrush with a 50%off coupon from Michaels!!! I still need to get a compressor though - they were a bit "pricey-er" than expected --
...

Don't get a dedicated air brush compressor. As you said, they are way over-priced for what they cost. I picked up a 2 gal. "generic" compressor with regulated supply pressure for less money, and it is not only more than adequate for airbrush use, it's big enough to use for other things like pumping up a car tire, etc.

SNice,

Harbor freight had a compressor for airbrush, around $69.00 for 1/8 HP. They have another 1/5 HP airbrush compressor for $89.00. This one has an airbrush with it. Still a bit of money, but mine was priced $135.00 10 years ago!

I so get the airplanes smell nice thing, got to love Talc Baby Powder. I got some foot powder once, P.U. to that. The plastic bottle thing is cool in it's own right and will still be used when possible around here, vacuum table or not!

Had to abort the Maiden this weekend. Had it out at the field yesterday. Did receive some oohs and aahs and a few laughs from the gassers. Was ready to taxi her out to the runway and the Master Warning Light came on. Back to the hangar. The retracts were loose and getting wobbly, probably because I hot glued them in the pockets and it was 100 degrees outside degrading the glue.

Spent some time today making a balsa crib and then applied 30 min.epoxy. Pretty darn stiff now. Note to self: Don't get epoxy inside the gear. Had to exercise the retracts up and down several times so they would move freely. El stupido !

Then ,I noticed that after placing a 11v 2200mah battery in the cabin, it was going to be tail heavy from the get-go. Was sitting there on the table doing a wheelie. So, I added ballast, yes, weight, in the nose by making holes with my soldering gun and inserting a couple of aa batteries. I think she has ample thrust. Ran up the e-flight 66's. Good power.

At this point, I'm not 100% certain where the CG should actually be. Lifted her with my fingers about 1.5 inches from the leading edge. Seems okay. Drove her around on the driveway again and she taxi's nicely. Turns on a dime too

So, I'll have to wait till next weekend as I'm traveling until then although I have short window Tuesday night at our club meeting. We'll see. "Triple 7 Sierra Lima Heavy" is as ready as she's going to get.

Keep you posted on the progress and fate.

Cheer's

Hawk

Originally Posted by dahawk47

...
Then ,I noticed that after placing a 11v 2200mah battery in the cabin, it was going to be tail heavy from the get-go. Was sitting there on the table doing a wheelie. So, I added ballast, yes, weight, in the nose by making holes with my soldering gun and inserting a couple of aa batteries. I think she has ample thrust. Ran up the e-flight 66's. Good power.

At this point, I'm not 100% certain where the CG should actually be. Lifted her with my fingers about 1.5 inches from the leading edge. Seems okay. Drove her around on the driveway again and she taxi's nicely. Turns on a dime too
...
Hawk

You are WAY nose heavy! My CG is 4-3/4 in. aft of the wing LE at the wing root... same place as the stock glider. It sounds like maybe your main LG is too far forward, so the CG is behind the main LG and the tail naturally drops?

The CG is discussed elsewhere in this thread... a search on "CG" should locate the posts. Good luck on the maiden!

Thanks Tom,

I'll take another look at it. I placed the mains at a point where I thought the wing would handle them. Much more toward the trailing adge and I'm not sure I could have mounted them at all. They are in the center of the wing. Good thing is I can remove some of the fore ballast.

+1 to what Tom Frank said about the CG location -- it should be about the same as the stock glider as long as you have not modified the wing sweep.

Hawk - Sorry to hear about your maiden troubles -- but better safe than sorry! You will get her up! Don't pay any attention to the "haters"!

Thanks to all for the air-compressor suggestions -- I will definitely look up all the leads you guys gave me!

As for the Baby Powder reference -- it is part of Freddie B's paint technique. Here is a link to the post where I first learned of it:
http://www.rcgroups.com/forums/showp...&postcount=211

The thunderbird 70mm EDF titan is ready for maiden. Hopefully I will be able to get her up soon!

Air Hogs TITAN RC FLEET - SNICE RC (5 min 31 sec)

Originally Posted by dahawk47

Here is a preview of the Air Hogs Airliner "A" Model. I'm not finished with it yet. About 90% complete. Need to wire up the twin edf's and include an external bec. Add decals, etc.- Hawk

Will repost when she's complete and ready for maiden.

Hawk, this is AWESOME!!!

SNice,

Love your fleet and video. The first EDF flew good with no wings or tail? (LOL ), But really your crew chief and his helper sure bring back some good memories of my two boys at that age (25+ years ago ) Enjoy themi it goes by so fast I can tell you are a great Daddy by the way they interact with you and the fleet in the video!

Fred

Thanks Freddie B!
Yeah -- I thought I added an annotation about that V1 EDF -- that is what is left of it! lol -- It was dismantled due to lack of performance!lol

...So I did the maiden this morning and it was a complete success!!! Super stable, highly maneuverable, and a very wide speed envelope. The stall is pretty tame-- she just drops a wingtip and then the nose - no nasty spins or spirals. Recovery is pretty quick given enough altitude.

In flight behavior was stable but extremely responsive -- After the first toss, I had to dial down the throws because she was a bit too twitchy. I still need to lock in the correct throws - perhaps I will reference similarly sized foamy EDF's. The "twitchyness" was amplified by the fact that my thumbs were shaking the entire flight! Other than that - she behaved like an arrow -- went exactly where the nose was pointed - possibly due to the anhedral in the tail (???).

Launch: Uneventful -- didn't have to throw her nearly as hard as I thought I would. Gave her a firm toss at about 20deg and 60% throttle -- off she went -- no dip-- she was immediately on step.

Landing: This was a bit of a challenge! With flaps down, it took me 3 landing attempts to get her back to earth! The glide slope was so shallow that It took forever to get her down. I had to fly her down to the ground. Normally on my approach (with other planes), I hold the elavator, and use the throttle to control my descent....this plane would not land!

So I'm very happy with maiden performance. Trim was perfect -- all surfaces at 0 deflection - just need to lock in the control throws.

Got video of the maiden and will post once I have a chance to edit...

Here are a few stats from the completed model:
AUW: 34.4oz (w/ 2650mah 3S lipo)
ESC: 60A
LIPO: 2650mah 3S 30C
MOTOR/FAN: 3900KV/70mm
WS: 32.5" (approx)

Hawk - you should be fine with regard to weight!!! Those twins should supply more than enough power! I rarely went above 60% throttle on my maiden and performance was still excellent. Definitely move your CG back -- mine was about 4.75" behind the leading edge root (stock glider location).