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RC_Junky 05-20-2002 02:26 PM

Diamond Dust Questions
 
How much building actually goes into building a Dust? Will standard servos work? If not what Futuba compatible ones will? Will a MVVS .40 GFS/R be a good engine on a Dust as a first fast prop plane? What kind of speeds should be expected from this combo? Thanks all.

MMallory 05-20-2002 07:01 PM

Diamond Dust Questions
 
RC Junky,

The MVVS will give you the speed you want. However the price to pay for speed is you must have better servos. The best deal going now are the Hitec digitals (around $50 each). If you put a .36 sized engine you can go for lower end servos. I won't guess at your final speed, but I can tell you, the Dust is FAAAAST.

Mark M.

RC_Junky 05-20-2002 07:07 PM

Diamond Dust Questions
 
What's the model #'s of these Hitec digitals? And what are you other Dusters using for servos?

MMallory 05-20-2002 07:32 PM

Diamond Dust Questions
 
Hitec 5625 or 5645 are the $50 versions
The 5925 and 5845 are about $80 and are coreless.

RC_Junky 05-20-2002 07:36 PM

Diamond Dust Questions
 
Thank you.

Dustflyer 05-20-2002 08:46 PM

Dust
 
1 Attachment(s)
RC Junky,

The world's record for framing a Diamond Dust, according to Jeff Gilbert, the designer, is 2 1/2 hours. The whole airplane is six ribs, some fiberglass tubes for spars and leading edge, a hunk of plywood for an engine mount, some balsa for the fins and elevons and not much more than that.

Figure a couple of hours for covering. Make sure you use Ultracoat and paint everything with Balsa Right before hand, ignore the recommendation not to do so in the Ultracoat instructions. Wrap the covering underneath the leading edge and seal the seams with finishing resin.

You will spend the most time, a few hours at least, installing the engine, servos, etc. If you plan on using the MVVS you will have a very fast airplane. Do not use cheap servos, use high torque ball bearing stuff. I am currently using JR 8101's (after burning up FMA coreless ones) and they work great. If I was doing another I'd use JR mid-size 9411 digitals. I use an FMA Quantum receiver and it works well.

Best flight characteristics (no trim change with power change and nice glide characteristics) are with the CG at the aft end of the range, right on the front spar.

Good luck!

Cactus. 05-23-2002 07:57 AM

Diamond Dust Questions
 
1 Attachment(s)
i have Ballraced standard 3004's? is that the right number?
on really high speed i do notice that i loose that sensativity around center stick, might be the servos not coping. i've got a MVVS half tunned 40 up front, with a APC 9x6, got a 9x8 to try when weather improves, no idea of rmp, but i've heard it max out a couple of times.
The covering is really important, i did mine in Solarfilm, and even used the gule stuff to tack it batter and seal the edges, but after a few landings the film around the bottom of the engine mount lifted and i lost it mid dive. i kept flying slowely for the rest of the flight :)
its now been replaced by Solartex, tho ony this center bit, the rest has tape over the edges to reinforce

MMallory 05-23-2002 11:02 AM

Diamond Dust Questions
 
Phillybaby,

Be careful when you change props. The 9x8 is probably going to give you a 30% increase in speed (if you maintain the same RPM). My first dust got a bit of flutter and broke both servo arms. Remember load increases exponentially with speed.

Mark M.

Cactus. 05-23-2002 11:33 AM

Diamond Dust Questions
 
1 Attachment(s)
i used to get a nice 5' "jump" oh high speed passes as the 2.5mm threaded rods ( that came with it SH ) flexed, this only allowed up movement. i've added CF tubes over the rods, the ID was about 3mm so i still had a bit of flex so i used these nuts to tighten the whole lot up, it dont flex anymore :D nice strong control horns and small servo disks with only enough cut away to allow full movement.
i think i'll get blow back way before flutter. :)
thats if i can get the 9X8 to run, that 9X6 was a pain the the ***** till i got the pipe lenght right, and it can still muck about if im one click off on needle

RC_Junky 05-23-2002 11:54 AM

Diamond Dust Questions
 
Just tached my MVVS .40 with the mini tuned pipe, enya #3 plug, APC 9 x 8 prop. At sea level it peaked 15,000 to 15,200 on 10 different runs. This was all it had before noseing over using a Globee Intellitach tach. What kind of speeds do you think I can expect on a Whiplash tached at 14.7? Also what's your thoughts on Hitech 605's (.77 oz dual BB servos) on this experiment?

Cactus. 05-23-2002 12:05 PM

Diamond Dust Questions
 
1 Attachment(s)
i'd imagine the whiplash has a better aerofoil section and will slip faster though the air, i also see a hint of a fuz whch means you can thin the section and go even faster. no covering problems with whiplash either.
your MVVS, if i remember right the GFS/R is the rear induction rear exhaust puppy right??? OOOOHHHH MAMMMA!
we clocked ( very inaccurate, think to slow ) my own design Delta, which is uncannley like a Whiplash at 160-170 mph with this engine and a 8x10 APC, this was 30 mph quicker than any other plane timed during that session, but the other planes should have been doing that speed, hence we think the trap was wrong and we where close to 200 on the flat.
personaly i think i would have the Whiplash, but i wouldnt want to damage it in anyway, Dusts are TOO! easy to fix :D

use this graph and draw a line between pitch and RPM to get rough speed, not sure how much drag ( if any ) it takes into account

RC_Junky 05-23-2002 12:23 PM

Diamond Dust Questions
 
No, my engine is the MVVS GFS/R side exhaust front induction, not the pylon racer.

Cactus. 05-23-2002 12:29 PM

Diamond Dust Questions
 
AH! that would be what i have too then. if its not tooooo old, turn the exhaust port around with the liner. this dosnt damage the piston liner fit as they are both round, but.. on older engines it can because they wear diffrently in diffrent places.
it'll make mounting your pipe a lot easier, give less drag, and its suposed to be a quicker engine.

RC_Junky 05-23-2002 02:29 PM

Diamond Dust Questions
 
phillybaby, are you sure? I know they say you can make it side or rear exhaust before you run it the first time but not sure about after they have been run. My engine is a newer one bought last year and has about 2 gallons thru it. Have you done this and does it work without problems?

Cactus. 05-23-2002 02:44 PM

Diamond Dust Questions
 
2 gallons, nicely ran in...
running in is mostly about making them the same diameter, not making them both fit only one way like a kiddies toy.
as long as you still have good compression its fine. i've not done it my self, but i wouldnt worry about it on the two i have. if not, a new piston liner set of these is dead cheap, and then you more or less have two engines. also.... with new piston and liner set you can go from the standard to tuned engines as easy as that.
like i said, i've not, because i've only had one plane on each engine, but another friend used to swap them back and forth nearly every couple of weeks with no adverse effects.
simply undo the hed, then the next 4 bolts underneath, rotate it round, do them back up, head on. bingo.
Dont blame me if it does kill it, but i've seen no problems. if you find its slower, you've only done a run or two anyway.
if it worrys you, i know here piston and liner set is about £12 cheap as chips!

RC_Junky 05-23-2002 03:02 PM

Diamond Dust Questions
 
phillybaby, just got off the phone with Robert @ Morris Hobbies, he says "technically he can't recommended it" but, you're right in everything you say and with only a short run time on the engine it should work without a problem. Also he says there's two things (bigger carb and or run the GRRT pipe) to boost power in this engine. Not sure what I will do but, I really like the look of the rear exhaust.

Cactus. 05-23-2002 03:10 PM

Diamond Dust Questions
 
1 Attachment(s)
i think i have the 7.5 mm on both my standard and half tuned ones. over here we can use the Perry carb, and then they scream. but they can be very picky on needle settings.
the pipe my friend had for his was a straight though mini pipe, little black job, looked like that orbiter in the apollo missions LOL.
heres his set up on a delta design of mine

RC_Junky 05-23-2002 03:21 PM

Diamond Dust Questions
 
That's the same pipe I have only side header, I think I will run what I have and see what it does for now.

david200mph 05-24-2002 04:14 AM

prop size for 45 ducted fan
 
HI GUYS, SOUNDS LIKE SOMEONE HAS BEEN DOING THERE HOMEWORK ON FAST FLYING DELTA AIRCRAFT. I HAVE A QUESTION I HOPE SOMEONE CAN ANSWER. WHAT SIZE PROP SHOULD I RUN ON A O.S. 45 DUCTED FAN ENGINE TO GIVE GOOD PERFORMANCE ON MY DIAMOND DUST? (WITHOUT BLOWING IT UP). ALSO WHAT PROP SHOULD I USE TO BREAK IT IN WITH. :confused:


THANKS A BUNCH
DAVID 200MPH

ChuckAuger 05-24-2002 02:07 PM

OS DF Engine
 
I don't know about the 45..I have an OS 46VRDF on mine. I run the APC carbon fiber 7.4X8.25 Q40 prop. But you will need to do some machining on the fan adapter nut to get a D1 hub APC to work..the hub is .550" thick and there are not enough threads to even go thru the hub. The nut has to be turned down and the prop hub drilled out to work. But I have maybe 100 flights and it hasn't blown yet..

marc sommer 06-06-2002 08:29 PM

Diamond Dust Questions
 
Hello everybody.I'm trying to order a diamond dust and keep getting a delivery failure notification.Does anybody know another way of getting hold of them(by computer)??Regards Marc Sommer

miderror 06-06-2002 11:56 PM

You can call
 
DIAMOND DUST RC
10251 NE 110th St
Archer, FL 32618
(352) 486-2159


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