Diamond Dust Engine Selection
 

I will receive soon my diamond dust kit
this will be my first glow powered fast plane.
As engine selection I plan to start with a OS 46FX and after familiarisation move to a jett BSE.50 rear exhaust

What my I expect as performance ?

MY jett engine is not ordered yet, but I feel this could be the ultimate motorisation for that plane.
Does anyone fly this combo?

Diamond Dust Engine Selection
 

you may find you really like the fx on it. as most dd's don't last thru many engine changes, i would fly the crap out of it with the fx. if you feel you want more, build another for the jet. these airframes are flimsy at best and will vibrate themselves apart, so many engines will definately wear it out! my fastest had a super tigre 51 on it and was quite fast. i currently have a whiplash with a 46fx on it and at this time am happy with it, but the lash does not fly like the dd!---henry

Diamond Dust Engine Selection
 

mmmmmm i never saw a DD except on picure. It's not a common model here in my country.
You say those planes are structuraly weak?

Diamond Dust Engine Selection
 

no i didn't say that, what i said was they are flimsy at best. what you have is two lite ply center ribs and eight balsa ribs with two arrow shafts tying it together. the result is a super lite flying engine!---henry

Diamond Dust Engine Selection
 

howw ok, sorry my english is not excelent

dd structure
 

This plane is more of a kite than a plane. Its mostly air.

Diamond Dust Engine Selection
 

I see what U mean, well I will wait to receive the kit before posting more stupid coments !!!!

Diamond Dust Engine Selection
 

The DD does not have much to it but it sure can take an abuse in the air.

But very fast to build and a bunch of fun to fly

well..
 

I stumbled into a MVVS 40 GRRT this engine (from what I am told..) will turn 25K-

Now that is S C R E A M I N'

It was one of Walter Morris' (Morris hobbies) pylon engines-

I am thinking of getting a DD just for that motor!

james

Diamond Dust Engine Selection
 

Razor

I say go for it! I have the same engine except its the GRRT FAI version. It tacs at 24,100 on ground and really unloads in air. It is extremely fast and fun to fly.

I have a video of it on pipe and one off pipe. you can tell the difference in the two.

7 yrs old?
 

This one is supposedly the FAI version also-

I usually dont like those delta things but after researching the DD and GRRT combo- I am compelled to give it a try!

james

Diamond Dust Engine Selection
 

I just bought my GRRT a about a year ago. Only thing i can see different is the exhaust port is round and does not need the small adapter from engine to pipe. The pipe clips right on the engine. Another thing is I had to drill 2 mounting holes because the way it comes is a bit weird. It has 2 up front near front of engine and 2 in rear. I drilled out 2 more so it bolted like a regular engine.

Engines
 

SALMONBUG,

A great choice of engines!

I started out with an OS 46FX on my Dust and loved it. Use an APC 9X8. The airplane will be plenty fast with that prop, I'd guess 120-140 mph out of a dive. Plenty of thrust for a launch.

After the OS I dropped a rear-exhaust Jett into the same Dust. You will get a very significant boost in performance. I found the best props are APC 9X8, 9X9 or 9X10. Expect 18K plus rpm with the 8 pitch. As I recall I was turning about 16.4K with the 9X10.
I later bought a new header and slowly cut away a 1/4" at a time until I was able to retune the engine for over 17,000 rpm with a 9X10 prop.

I tried going the high rpm, little prop route and the airplane just didn't seem as fast. You need a certain amount of thrust to overcome a given amount of drag and it seems like the 9 inch APC's work the best on the Jett 50 for me.

You can expect speeds well over 150 with the Jett. I haven't had a chance to put a radar gun on it but I am guessing somewhere over 175.

Diamond Dust Engine Selection
 

thanks a lot dustflyer for your coments.
I am still waiting my dust kit as soon I receive it I will assemble it.

Diamond Dust
 

I've got a D.D. as well, actually just building 3rd one now. What I do is replace engine mount with 1/4" ply and add 1/8" lite ply doublers from front to just behind the front spars. I'm using a Rossi quicke engine and pipe with 8-8 APC prop. Haven't had a radar gun on it but timing on known distance -lenght of flying field- puts it at 180-190 MPH. What a blast!! Good luck with yours.

Don

Engine mount
 

It's funny about that engine mount in the Diamond Dust. I must have over 150 flights on mine, at least 100 with a Jett FIRE 50 and the stock mount is still fine. All I did was harden the holes with CA, fireproof it with finishing resin and put a little triangle stock along the edges when I built it. It's still as good as new.

Diamond Dust Engine Selection
 

for those who are interested in a very accurate speed mesurement from their planes and won't have a radar gun at the field, just send me a wave file with the sound of your plane at full speed passing above a simple tape recorder, tell me also the temperature of the day.
if you can tell me the distance from and above the tape recorder when the plane pass it's better, but not very important.
try to make your low pass as close as possible of the tape recorder in order to minimise the "relative speed error"

I will give you a highly reliable speed info and also your rpm

the most low passes i have on the tape as better it is for analyse.

Diamond Dust Mods
 

Hi Dustflyer: I made engine mount 1/4" cause on first one I had a MVVS .40 on it at first that ran a little rough at idle and a little beyond, even with balanced prop and spinner and maybe because of a couple of less than perfect landing the original mount was starting to come apart. On that one I laminated a pce of 1/4 lite ply to it. Next ones I built [from scratch] I've just used 1/4 ply and been done with it. First one I lost to a wind gust hitting it on launch [thats my story and I'm sticking to it], second one , one of the pushrods to the eleveron came loose or something, went into a flutter and into the ground in the blink of an eye. Needless to say there wasn't much left, hence now i'm on #3. Just have to cover it now, between other plane projects on the go and come spring I'm set to go again. Doing the couple mods I did added negligible weight but a lot of strength.

Don

Diamond Dust Engine Selection
 

I doubled mine up also. Mostly because on my first DD my engine bolts after tightened kind of sunk into the stock mount. So on my second I doubled up on top and bottom. Been working good ever since.

Diamond Dust Engine Selection
 

I received my DD kit this morning, I opened the box and I first tought that I only receive a stock of newsparers sheets.
There is nearly nothing in that box.
I'll start building next week, I have a other project on the workbench actualy

Kit
 

SALMONBUG,

It's amazing, isn't it? I had the same thought when I got mine.

I really enjoyed building it, I think you will too. It is a very unique design.

You might want to give some thought as to how you want to launch it. In my case I just filled in the area between the fins with lightweight balsa and widened the notch between the elevons. To launch I just grab it between the elevons, thumb on top and fingers on the bottom, hold it in front of me and let it go.

Launch photo
 

Here's an incredibly lucky shot of a launch. With the Jett FIRE 50 it pulls away so fast the photographer had to anticipate when I was about to let it go. As soon as I raised my arm he hit the shutter and got the shot.

Diamond Dust Engine Selection
 

GREAT picture !!!!!
I think I will have fun with that stuff!!!

Diamond Dust Engine Selection
 

about the launch, My usual method to launch bird is above my head, so i first planed to build a skid to allow to hold the plane in the hand and also protect the belly and wing during landing, But after seeing the picture of dustlflyer, I have to admit that his launch technique has a little bit more class.....

I admire the technique and the very cool attitude on the picture

Diamond Dust Engine Selection
 

thats about the best way to launch it. Or just have someone launch for you always helps to.


In my case if i give it a shove or if others do it acts a bit crazy I found that if just just hold it WOT and let go it pulls away smoothly.

Make sure you lean it to the right a little bit to counter the torque.