CG of Estes Saturn V?
Tim Farris
to fly with a D12-3? I'm modifying mine for the heavier E 15-4, and I
want to get the thing balanced correctly. TIA,
Tim
Tom Binford
The SU E15-4 isn't any heavier than a D12-3.
Tom
Billy Hutson
I'm pretty sure that the AT motors weight almost the same as the Estes
engines. I even beefed up the CRs with some ply and epoxy and I didn't need
to add any nose weight with an AT E30.
Then again, I could be wrong. <G>
Bill
skyw...@home.com
"Tim Farris" <timothy....@vanderbilt.edu> wrote in message
news:39065899...@vanderbilt.edu...
Greg Cisko
news:39066542...@frontiernet.net...
> Tim Farris wrote:
> >
> > Could someone tell me the center of gravity of an Estes Saturn V prepped
> > to fly with a D12-3? I'm modifying mine for the heavier E 15-4, and I
> > want to get the thing balanced correctly. TIA,
> > Tim
>
However the fact that he is even asking leads me to believe that
this information (the CG) is not included with the kit. I haven't
opened my kit up yet so I don't know. But I would certainly expect
the MFR to tell you where the CG is. I remember going through
this when I was a kid in the early 70's.
--
Header address intentionally scrambled to ward off the spamming hordes.
cisko [AT] ix [DOT] netcom [DOT] com
Bob Kaplow
> However the fact that he is even asking leads me to believe that
> this information (the CG) is not included with the kit. I haven't
> opened my kit up yet so I don't know. But I would certainly expect
> the MFR to tell you where the CG is. I remember going through
> this when I was a kid in the early 70's.
Toto, I don't think we're in the 70's any more...
:-)
Bob Kaplow NAR # 18L TRA # "Ctrl-Alt-Del"
Kaplow Klips: http://members.aol.com/myhprcato/KaplowKlips.html (baffle too!)
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Tim Farris
Tom Binford wrote:
>
> Tim Farris wrote:
> >
> > Could someone tell me the center of gravity of an Estes Saturn V prepped
> > to fly with a D12-3? I'm modifying mine for the heavier E 15-4, and I
> > want to get the thing balanced correctly. TIA,
> > Tim
>
> The SU E15-4 isn't any heavier than a D12-3.
>
> Tom
According to the data sheets on the NAR website, the E15 is about 10
grams heavier. That may or may not be significant. At the risk of
starting a flame war, and definitely *not* meaning this as a slam on
Tom, I just want to know the CG. I don't want a discussion of the
relative masses of motors or what things were like 30 years ago or what
manufacturers ought to do. I just want to know where the CG is. Can
anyone answer that? Thank you
David Erbas-White
there! <G>
David Erbas-White
Greg Cisko
> According to the data sheets on the NAR website, the E15 is about 10
> grams heavier. That may or may not be significant. At the risk of
> starting a flame war, and definitely *not* meaning this as a slam on
> Tom, I just want to know the CG. I don't want a discussion of the
> relative masses of motors or what things were like 30 years ago or what
> manufacturers ought to do. I just want to know where the CG is. Can
> anyone answer that? Thank you
Looks like you are not going to get it. Maybe it's time to get VCP
or some other CG/CP calculator? I am kind of surprised that out of
all the people here that built Saturn V's no one remembers or will
tell you. I guess I can assume it is not in the instructions?
nick...@my-deja.com
Tim Farris <timothy....@vanderbilt.edu> wrote:
> Could someone tell me the center of gravity of an Estes Saturn V
prepped
> to fly with a D12-3? I'm modifying mine for the heavier E 15-4, and I
> want to get the thing balanced correctly. TIA,
> Tim
>
Did you ever get an answer? (I mean with the CG?)
Nick
Sent via Deja.com http://www.deja.com/
Before you buy.
Tim Farris
No
THF
Tim Farris
I've got VCP, and have the CP in hand. I'd like a measured CG without
finishing the build myself rather than a calculated based on my best
guess of all the parts parameters.
THF
Andrew Waddell
adjusted after assembly to be at least one body diameter ahead of the CP.
I'd suggest leaving the NC/tower section unglued from the rocket so you can
add nose weight to the bottom of it as needed, then glue it in place once
you're done with the weighting. Would also suggest not attaching the little
disc that seals off the bottom of the NC/tower section until you're set with
the weighting either, because you could put modeling clay in the NC before
putting the disc in if you need weight. I'd also suggest putting a small
bolt about 2" long through the disc with the threads protruding toward the
bottom of the rocket, so if filling the NC with clay isn't sufficient weight
you could stack flatwashers on the bolt and secure them with a nut until you
get the noseweight you need to get the CG/CP relationship right. When you're
done putting clay in the NC, then glue on the disc, and continue adding
washers to the bolt as needed, THEN glue the whole shebang onto the top of
the rocket.
By the way, what did you get for the CP number?
--
Andrew D. Waddell
PML Online Support Rep
TRA 2043 L2/NAR 52875 L2
Email: ADWa...@home.com
PML: www.publicmissiles.com
"Tim Farris" <timothy....@vanderbilt.edu> wrote in message
news:390AEE6E...@vanderbilt.edu...
Bill Schworer
I sent you a direct e-mail last night since I hate to have to modify my address
with "no spam" for posting.
The Essence site, Saturn V FAQ under detailed cluster motor mount, lists the
stock CG as about 15.5 inches forward of the aft end of the rocket. I just
tried to get back into the web site, for some reason the server is not
responding. There is a lot of good info there on the kit, if you haven't
checked it you might find some useful extra information there.
I am currently building the kit to take an Aerotech 24mm reloadable, to fly on
E18-4. I am going to beef it up a bit.......would appreciate knowing your
calculated CP. I will probably have to add some nose weight.
Thanks, Bill Schworer
Tim Farris
(different than some), and the fins flush with the end of the main body
tube. With that, the dimensions I measured by hand and put into VCP
give a CP of 33.2 cm or 13.1" from the aft end of the body tube. YMMV.
Thanks for the rec's about weighting (pun intended) after assembly. I
was really just wanting to get on with it. I'm in the middle of several
different steps in the building, and I didn't want to put anything else
off for fear I would forget something or do something too soon.
Tim
Andrew Waddell wrote:
<snip>
>
> By the way, what did you get for the CP number?
<snip>
Connery
at 21" from the tip of the Command Module.
Connery Carroll
NAR #77226 L1
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Greg Cisko
news:1397c7d5...@usw-ex0103-023.remarq.com...
> I just measured the CG on my completed Saturn V. The CG came in
> at 21" from the tip of the Command Module.
Thanks!
Mario Perdue
<connery.car...@trane.com.invalid> wrote:
>I just measured the CG on my completed Saturn V. The CG came in
>at 21" from the tip of the Command Module.
Mine measures 21.5" from the tip of the CM. I probably used more paint
on the upper part of mine. :)
Mario Perdue
NAR #22012 Sr. L1
http://www.L4software.com/amorea
"X-ray-Delta-One, this is Mission Control, two-one-five-six, transmission concluded."
Essence
I am planning a Saturn V update - ready tomorrow morning (5/1) which has
a bunch of new input (including information from this thread).
- Nick
--
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Bob Kaplow
> On Sat, 29 Apr 2000 13:52:21 -0700, Connery
> <connery.car...@trane.com.invalid> wrote:
>
>>I just measured the CG on my completed Saturn V. The CG came in
>>at 21" from the tip of the Command Module.
>
> Mine measures 21.5" from the tip of the CM. I probably used more paint
> on the upper part of mine. :)
That would move the CG forward, not back. Your extra paint must be on the
tail.
Mario Perdue
Kaplow) wrote:
>In article <iudngsof5qgtv3s6a...@4ax.com>, Mario Perdue <mpe...@hrtc.net> writes:
>> On Sat, 29 Apr 2000 13:52:21 -0700, Connery
>> <connery.car...@trane.com.invalid> wrote:
>>
>>>I just measured the CG on my completed Saturn V. The CG came in
>>>at 21" from the tip of the Command Module.
>>
>> Mine measures 21.5" from the tip of the CM. I probably used more paint
>> on the upper part of mine. :)
>
>That would move the CG forward, not back. Your extra paint must be on the
>tail.
Um, I meant 'extra light' paint. Yeah, that's the ticket... :)
Connery
construction I could epoxy in some weight. Since I was only
going to fly this bird on an AeroTech E15, I added enough weight
to move the CG forward 1 inch, so now it sits at 20" from the
tip of the CM. I flew it first on a E15-7 and after the thrust
cut out and the rocket arced over at apogee, it started falling
flat (parallel to the ground) then the ejection charge finally
fired, and the bird was recovered safely. The next flight was
on an E15-4 and the ejeciton charge fired right at apogee for a
perfect recovery.
