RE: (Something Fast?) Delta Build Thread
 

HaveBlue,
I was tempted to sheet the whole wing and calculated it would have taken an additional 2.77 oz. (79 grams) of balsa. Since my open bays are not huge like on a dust I am not sure what the advantage would be other then strength. Any thoughts on sheeting vs covering when it comes to speed? It seems like tight small areas of covering should not be much of a problem and you do save a little weight. Maybe I shouldn't worry about an oz. or two since it looks like it will have a RTF weight of well under 3 lbs.

I am going around and round in the aerodynamics forum concerning cowls. Could you post a picture of your engine cowl and has it been tested in any way?

About ready to post pictures of the finished product later tonight or tomorrow. Need the rain to stop long enough for a couple of outside shots as they turn out so much better in bright light. 10+ inches of rain last month and may pass that that this month. Maybe I should have been building a boat, A really big one.

I Don't even have a radio for this plane so this may be the perfect time to get the new Futaba 6EX 2.4.

RE: (Something Fast?) Delta Build Thread
 

Razor says that there aren't enough fast glo planes at our Revver events so I need to throw them a bone ;) I also need to fit in with the guys at my field with the Shrikes and Mach Racers.

RE: (Something Fast?) Delta Build Thread
 

Four days since I started the build and one day was spent on the engine cowl. No wife, kids, dogs or real job helped get it done quick.
The hardest part was sanding and documenting the build sequence. I did not spend day and night on this project and next time will be quicker. I have two servos mounted but still need a radio for it and a fuel tank.

I was able to calculate the final RTF weight and it will be 2 lbs 12 oz if no tail weight is needed to balance.

My goal was to

Quick build - yes
Low weight - yes
Clean lines - I think so
Low cost - Just under $100 to build and cover
Look good - You be the judge. I kind of like it
Fly good and FAST - Time will tell

I would appreciate any comments positive or negative.

RE: (Something Fast?) Delta Build Thread
 

OK, Mike. You can't go posting a thread like this and NOT offer at least the plans if not a short kit. That looks fantastic and I need one!


Mark

P.S. - I guess you could put me in the "positive" comment column...:D

RE: (Something Fast?) Delta Build Thread
 

Thanks Mark,
I just hope it flies as good as it looks. I really need to get a radio so the real test can begin. If it does fly well I could just reorder every thing in larger quantities and stick them in a box for shipping. We will see what happens.

Thanks for your help a few weeks ago on the PDF printing. With the right plotter driver installed I can now print the plans to PDF in exact E size.

RE: (Something Fast?) Delta Build Thread
 

More info on the cowel please. It looks great!

RE: (Something Fast?) Delta Build Thread
 

Beautiful- ALready a winner I am guessing

RE: (Something Fast?) Delta Build Thread
 

Mike,
Nice to see where the cowl ended up, wow that ought to have a nice cruise....

Warp speed anyone?

Bet you will hear that prop unload fast.

RE: (Something Fast?) Delta Build Thread
 

I can't wait to see what kind of Ghetto covering job you put on this one[sm=lol.gif][sm=wink_smile.gif]

It looks pretty good Mike, I really like the trick cowel.

RE: (Something Fast?) Delta Build Thread
 

Thanks for the kind words. As far as cowl concepts, I opened a can of worms in the Aerodynamics forum so anyone interested in seeing my first attempt insulted :D should visit the two page thread. Lots of do's and dont's. Those guys know quite a lot about it.

As far as my construction method it is all balsa covered in glass and painted. I worked on it on and off for much of a day to get what I wanted. I started with the engine mounted in the plane. I started with very lite 3/32 balsa that was wet and wrapped it around the front half of the cylinder and extending to the rear. The front was also lite balsa with a hole for the carb intake and bent around the front to the back side of the nose ring where there is one of the two screws to hold it on. I kept adding on to get a snug fit around everything that needed covering. On the inside joints I put 1/4' tri stock so I could round the edges. On the outside at the base of the cylinder I used 1/4" tri stock that was wet and had small cuts on the front and back so it would wrap around the curve. Sand it, glass it and paint it. Covering would have been a real pain. It ended up weighing less then half an oz. and I could probably throw it across the room without any damage.

Is that what you wanted to know?

RE: (Something Fast?) Delta Build Thread
 

At this point I have settled on the name "Screamin Demon" (misspelled on purpose) but am open to suggestions if anyone has any ideas. There is also "Ms Raptor" or...

RE: (Something Fast?) Delta Build Thread
 

Looks really well Mikey!:D
I think I will put a Jett .50 in mine.[X(]
It will compliment my jett.90 just fine.
Keep up the good work.
How did u manage no wife, kids or dog?
u can tell me your secret
SJ

RE: (Something Fast?) Delta Build Thread
 

Of course the Jett 50 will work fine. I really like twice as much thrust as weight. I am hoping it is clean enough to run some small diameter, high pitch props for serious speed.

I divorced the wife, sold the kids and killed the dog a long time ago and have remained free. (didn't really kill the dog)

RE: (Something Fast?) Delta Build Thread
 

Very Sharp, I like it! Simple, clean, and easy to do. Next post we expect a flight report and nothing else!!:D

RE: (Something Fast?) Delta Build Thread
 

You mean I have to fly it?? I does seem like I may have seen a box around here with Futaba on it.

RE: (Something Fast?) Delta Build Thread
 

Yes you have to fly it!

Hope all goes well with the maiden of your Screamin Demon.

RE: (Something Fast?) Delta Build Thread
 

Yes must fly, and do take some vid and post it.....

RE: (Something Fast?) Delta Build Thread
 

i want a short kit too

come on fly it and sell it , can i buy the prototype :D

RE: (Something Fast?) Delta Build Thread
 

OK, I well get it airborne soon. I bought and installed the Futaba 6EX radio. The Spectrum 7DX felt a little better in my hands but the price, reviews, and single very small receiver pushed me to the Futaba radio for the first time since 1980. Set up and working great and programing the Expo and dual rates is all that is left. I used Hitec 225BB servos for the elevons and a small JR for the throttle.

The final weight (less fuel) came in at 2 lbs 10.8 oz with the CG just slightly forward of the forward limit. I will add one oz to the tail for the maiden which will still leave it a little nose heavy according to the CG calculator.

We have been getting 2 to 3 inches of rain every week for two months now. It is time for it to dry out.

RE: (Something Fast?) Delta Build Thread
 

You never know. It may be real cheap after the maiden flight. :D

RE: (Something Fast?) Delta Build Thread
 

Mikey, bring your new zoom zoom machine out to sunny Ca.[sm=thumbup.gif]
We have miles of sunny dry lake bed for your maiden!:D
I will even buy lunch![X(]
SJ

RE: (Something Fast?) Delta Build Thread
 

:D:D:D:D:D
The Screamin Demon has flown, twice
I went to the field to break in the engine and there were several pilots there. The brand new TT 46 Pro started right up with a 9 x 7 APC and I had to test peak rpm of 16,200 towards the end of the first tank. Everyone wanted to help and the next thing I knew it was in the air. Two people wanted to buy it before it flew and then that # changed to four after it flew. I guess I am going to have to put together a manual and a few kits.

A standing push forward in a light breeze had it climbing out at about 45 degrees. I could not believe that no trim changes were needed and it was hands off high speed passes. There were no excessive pitch changes when the power was added and I could not be happier with the flight characteristics. The dead stick landing did show it was a little nose heavy with a little fast and flat touchdown with the stick all the way back.

ON flight two I moved the CG back a little and launched the plane with one of the clubs better 3D pilots at the sticks. I had my video camera but the sun was so bright I could not get the plane in the 2 1/2" screen. I have a hood I made to block the sun but did not have it with me. He flew the plan until it ran out of fuel and after the landing I got two thumbs up and a big smile. The CG was still a little forward so another adjustment was made.

There was a lady there filming her husbands first flight and I asked her if she would tape mine on the first flight. She got about a minute of video of the slower passes and complained it was just too fast to stay up with. She agreed to email me the video she did get but said it could take a few days so we will see what happens. I am going back out there Saturday with a goal of getting some video of high speed flight.

All I can say is that I can't get this grin off my face. This plane looks good, flies good and is fast. Time will tell just how fast.

I do want to thank those that helped me in the "aerodynamics" forums with design questions and those in the "scratch build CAD" forums with mostly CAD questions. This project has been a blast.

RE: (Something Fast?) Delta Build Thread
 

Awesome Mike! What a great day for this!

RE: (Something Fast?) Delta Build Thread
 

Very cool! Congrats!

If you can get a good pass with audio I can doppler the speed.

RE: (Something Fast?) Delta Build Thread
 

Mike
Nice to hear all went well with the maiden. You have a nice design there, the hands off high speed passes must have been cool. You ought to post a follow up in the other forums about your design it is nice to hear feedback, we don't often frequent the other forums so sometimes we never get to hear the results. Have fun with it, you ought to kit it I'm willling to bet you will get a lot of interest.