| Mega Saucer:
This may be my Level 1 Cert rocket if I do not finish my Special project in
time for Naram :-)
Assembly is a little more involved than a normal saucer but still easy and
straightforward. Print out/Cut Out/Glue together the sections that VCP prints
using the data above. Transfer this to Thin Poster board. One large sheet and
one regular sheet. To make the same saucer the Large sheet is Silver and the
Normal Sheet is Gold (dim's later But basically the biggest one they have (I
figure at least 4x3 feet) ) Cut out and assemble.
Use this to make the Six Ribs for the inside of the saucer
The Ribs are made of paper Backed Foam board. Use CA to tack in place Radially
(3 fins like then the other 3 between those 3 for six total) then get the
joints good with the 20 minute or better epoxy. Now this next step is very
important
Very Important Step Follows
!!!!
The Six Ribs must be evenly spaced to privet erratic flights. Although at
the minimum safe distance for an H flight even it were to veer towage the crowd
it would be unlikely to reach them On smaller distances flying with F or G
engines it could reach the spectators. if the distance between each rib is not
the same when the skin flexes from the boost speed it will not flex evenly
causing differing amounts if drag or even vectoring on the uneven side. It is
not so critical that if you are off by half and inch it will crash and burn But
if you have a good eye and it looks ok then that is fine. Only gross errors
will cause problems.
If you want you can add braces in-between each brace abut 75% out from the
center Just make sure it comes in contact with the outer shroud or it will have
no effect. But Personally I like the aerodynamic deformation it undergoes at
speed. It looks cool and is actually more stable like that (increases the
shroud angle)
Next Attach the Upper shroud and epoxy good from inside. Be sure to leave
an Open hole large enough to fit a 1/4" launch lug! For the larger lower
shroud CA on one side of each rib OR white glue is more than sufficient since
Aerodynamics Hold this together not the glue. Once Dry make another upper
shroud except let it extend a little farther past the edge of the printout for
the outside diameter (make it neat and even!!!) epoxy the area just above the
upper shroud and BT and epoxy the inside outer diameter edge of the second
upper shroud and slide this onto the Saucer so that is overlap the original
joint and mates smoothly with the silver shroud (mostly for neatness and show
but it makes a big difference in looks!
Now cut off the excess Body tube to make it 1/4 past the top of the second
shroud.
The Bottom Plate is next. Before you glue this into place install a Full
length 1/4" launch lug. and make sure there is a hole for it in the bottom
plate. What I did was to take another piece of paper back foam board and using
a string and pin make a 2 foot diameter circle. Cut out the motor mount and
then proceed to remove the paper backing from both sides (saves a tremendous
amount of weight) Epoxy this into place (Ca will now eat it without the paper
backing. I then covered this in Thin golf foil wrapping paper type stuff (Golf
foil car stock is again heavy and strength in this component is not relevant
since the foam takes care of that.
Note the flights below are without a bottom plate or internal cross ribs
just to show how strong and stable the design is!
Recommended Engines: F20, F50, H55 (anything else in-between will likely
work But I have only flown it on the 2 F's and designed it for the H. usually
Longer Burn is better for altitude, Sound and Smoke effects etc.. Letter's in
the 50 range are best (F50 - G40 - H55 would likely produce some cool flights.
The F20 was a little tiny underpowered but the entire flight smoke effects are
incredible (see pics) I friction fit the motor in place with tape block on
nozzle end. retention is not important since there is nothing to eject. BUT the
thrust ring IS important!! I do not need ejection so I dump out the BP and use
it for my ejection charge challenged D12's :-)
Notice I have not spoken about a recovery system. That is because there is
none. The saucer flips over and descends featherweight like any other saucer.
It comes down so soft that YES I would not mind standing under it and having it
land on my head :-) I flew it in front of my entire club and the slow decent
rate was scarily eerie :-) The decent rate is about half that (Eyeballing) of
most of the successful cert flights I have seen. On one of the flights this
Saturday the saucer landed less than 3 feet from the pad :-) (see pics below
for entire flight sequence.) The delay was over 6 seconds which was very cool
for it had the cool smoke effects all the way to the ground (No Ejections
charge so no danger :-)
Some have worried that the rocket has SOooo much drag that the motor and
mount might fly through the rocket. Although this is NOT possible (ask anyone
who has held this and they will tell you) to belay these fears I will
permanently install a small 9" nylon chute attached to the MMT with 4
separate lines of Kevlar® so that IF the MMT flies free of the saucer it will
take the chute with it and this will allow the chute to open keeping the errant
MMT with burning motor in check. Nice show no danger. The Chute will not deploy
under normal conditions. I still feel this is not needed but it makes others
feel better and does not effect performance or fun so why not I say :-)
Built properly this rocket has strength that far exceeds its apparent mass.
Remember that those ribs are Epoxied to the MMT full length !! that is a Joint
18 times stronger than most any cert rocket. 3 times for each rid and 6 ribs.
IT is not going anywhere. (I tend to overbuild :-)
Also to note what I meant by vectoring. Note the first launch picture. See
that flattened panel that is slightly more flattened than the rest of the
panels?? Well you guessed it that is the direction it arched. (there was NO
wind this day as apparent with the landing location :-) can we say spot landing
champ :-)
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