HDTenEightyP/NetNews huggingface dataset:
From: paul@taniwha.UUCP (Paul Campbell)
Newsgroups: rec.models.rockets
Subject: Re: Other reloadables besides Aerotech? (Re: Info. about solid rocket-
Date: 28 Dec 92 21:49:15 GMT
Organization: Taniwha Systems Design

In article <Bzrs6r.477@usenet.ucs.indiana.edu> ntaib@silver.ucs.indiana.edu (Iskandar Taib) writes:
>This brings up another thing I've been wondering about. 
>
>How can one size of casing take both F and G reloads? The total impulse
>of one is twice as much as the other, so there must be twice as much pro-
>pellant in one grain than the other. Either they use two different pro-
>pellants with different "impulse densities" (impulse/volume) or they must
>have something take up the excess space. Is it a solid filler or is it 
>air?

There is no filler.

Well Fs really have a range from just bigger than an E to just smaller than a G
a 'full' F and a small G with different propellents might fit in the same
casing. In practice though one tends to buy a pair of ends and an assortment
of casings that take 1/2/3/4 grains to provide 4 different impulses with
the same propellent.

For example, I recommend that people who want to get into high-power buy an
ISP 29-40/60 reload which lets you fly Class C (if Fs/Gs), when you confirm
you can buy the 80/100 casings to fly Hs.

>Same thing for delays. In motors with delays, how do you put in different
>delay elemts since they'd be different lengths? I take it that any empty 
>space in a motor is bad.

The short delays have spacers on the propellent end (the delay still sits
tight up against the top of the motor - you don't want space to let the
ejection charge fall inside the motor). When you put your motors together 
getting all those spacers in can be a pain, they are a real tight fit - but
if you don't the delay grain can slip back under boost ....

	Paul
-- 
Paul Campbell    UUCP: ..!mtxinu!taniwha!paul     AppleLink: CAMPBELL.P
"Finally after much thought he tied a dollar bill to the top of the tree, it
seemed to fit - after all it was the premier capitalist holiday, besides after
the 'fall' of communism a star didn't seem appropriate anymore ..."
From: cdt@sw.stratus.com (C. D. Tavares)
Newsgroups: rec.models.rockets
Subject: Re: Other reloadables besides Aerotech?
Date: 29 Dec 1992 21:47:34 GMT
Organization: Stratus Computer, Inc.
Distribution: world
NNTP-Posting-Host: rocket.sw.stratus.com

In article <1hqbf4INNl4@cuda.add.itg.ti.com>, barrett@add.itg.ti.com writes:
>   Buzz, how do the cardboard spacers work?  

They're just body tubes.  Imagine a propellant slug with no propellant in it.

> Do they keep the flame off
> of the top surface of the top propellent grain (assuming that the
> cardbord spacer is on top). 

No.  Attempting to do so would be useless anyway.  Flame will propagate
into the tiniest crack or crevice.

> How do you ignite the top propellant grain
> if it is not at the top of the casing?

You put an igniter in it.  The propellant has a c-slot (dado) all the way
through it.  You stick a tape disk on the top of the grain to keep the
igniter from falling out the other end of the slot and into the void
where the spacer is.  The tape disks occasionally come unstuck and then
you do anyway.

>   If the cardboard spacers are at the bottom, then ignition would be
> straight forward, but the bottom surface of the bottom propellant grain
> would be exposed to the flame.

Reloads are coreburners.  Perchlorate engines in general are coreburners.
Both end surfaces burn in any case because they are "crevices."

>   Either way, a strange burn profile would result.  That may explain the
> wierd sputters that you hear with the Aerotech reloads (which I find
> annoying; reminds me of Jerry Irvine's motors).

More likely it's charred cardboard flakes trying to clear the nozzle throat.
-- 

cdt@rocket.sw.stratus.com   --If you believe that I speak for my company,
OR cdt@vos.stratus.com        write today for my special Investors' Packet...

Newsgroups: rec.models.rockets
From: ntaib@silver.ucs.indiana.edu (Iskandar Taib)
Subject: Re: Other reloadables besides Aerotech? (Re: Info. about solid rocket-
Organization: Indiana University
Date: Thu, 24 Dec 1992 15:25:39 GMT

In article <19921221181458.Roger.Wilfong@umich.edu> Roger.Wilfong@umich.edu  (Roger Wilfong) writes:

>1)  In the Aerotech RMS motors, the part of the case that gets the hottest 
>  is around the delay element.  You don't notice it on the 24mm and 29mm 
>  motors because this portion of the motor is smaller in diameter.  On the 
>  18mm, this portion is just the same diameter as the rest of the motor.  On 
>  the 18mm motor, this portion gets hot enough to char a motor tube while 
>  the rest of the motor tube is unaffected.

This brings up another thing I've been wondering about. 

How can one size of casing take both F and G reloads? The total impulse
of one is twice as much as the other, so there must be twice as much pro-
pellant in one grain than the other. Either they use two different pro-
pellants with different "impulse densities" (impulse/volume) or they must
have something take up the excess space. Is it a solid filler or is it 
air?

Same thing for delays. In motors with delays, how do you put in different
delay elemts since they'd be different lengths? I take it that any empty 
space in a motor is bad.

>2)  The 32mm Phoenix motor uses end burn grains in the F and G range.  The 
>  slot refered to above is about 3/16-1/4" wide (and deep) and serves two 
>  functions; first, it provides a place to put the ignitor, and second it 
>  provides the starting spike in the thrust curve that gets the plane 
>  moving.

I seem to recall that the slot went the whole length of the grain. I'll
have to have another look.

>3)  Since the Phoenix motor is only F and G rated, it is probably dealing 
>  with lower pressures than a high power motor.  A reload with a time/thrust 
>  profile of an I-65 might very well heat the case to an unacceptable 
>  temperature.  Although I suspect not - if pheonolic can stand up to the 
>  pressure and temperature, the aluminum casing should also.  What may be 
>  required is a thicker cardboard insulator tube.

Could be. Yet its an anomaly if reloadables are supposed to all be fast
burners. It doesn't have a delay so that would help the heat situation.






-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: NTAIB@SILVER.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS                 !
Newsgroups: rec.models.rockets
From: jackson@sn.jsc.nasa.gov
Subject: Re: 8' rockets..
Reply-To: jackson@sn.jsc.nasa.gov
Organization: Organization, City, State, etc.
Date: Wed, 23 Dec 1992 00:06:52 GMT

In article <1992Dec22.172713.19553@hpcvaac.cv.hp.com>, billn@hpcvaac.cv.hp.com (bill nelson) writes:
>CT80@music.mus.polymtl.ca (Steph) writes:
>: 
>: We are a Montreal-based amateur club building experimental rockets.
>: Our first one was 16kg, just over 5'.  We are currently working on
>: a second one which should reach around 26kg, 8', complete with its
>: own inboard computer and all the hooplas.  The problem is this :
>: the only clubs that we _know_ of that also make these kind of rockets
>: are in Europe.  Last year we had to fly oversea just to launch our
>: rocket (using a French booster, too).  Problem is this : it's not
>: very practical for us, and *I* couldn't go cuz the travel fares were
>: way too steep for me.  So I'm looking for people, addresses, anything,
>: anyone..  there has to be other clubs like us in North America!  If
>: you know of a place, if the place is you, or if you know there is
>: another, better suited newsgroup than this one, please let me know.
>
>It sounds like you are going far beyond model rocketry and High Power
>Rocketry.  If so, then you will have a difficult time finding kindred
>souls. There are one or two universities that have student projects
>using liquid fuels or rockets constructed out of metal. I do not recall
>which schools they are, however.
>
>Getting a license to experiment with such rockets in the US is extremely
>difficult.
>
>Bill
Newsgroups: rec.models.rockets
From: billn@hpcvaac.cv.hp.com (bill nelson)
Subject: Re: 8' rockets..
Organization: Hewlett-Packard Company, Corvallis, Oregon USA
Date: Wed, 23 Dec 1992 07:27:47 GMT

jackson@sn.jsc.nasa.gov writes:
:  
: Getting a license to experiment with such rockets in the US is extremely
: difficult.
:  
: Bill
: ...................
: I think this depends on what state you are in, I dont think here
: in Texas there are state laws restricting any kind of rocket
: building as long as you are not in a city or county that restricts
: fireworks, and maybe not even then.

Well, the poster is in Canada, so our laws will not apply. However,
here in the US, I suspect that there are a bunch of federal laws that
would have to be complied with.

Bill
Newsgroups: rec.models.rockets
From: bbs.byron@tsoft.net (Byron Reynolds)
Subject: F100-4's
Organization: The TSoft BBS and Public Access Unix, +1 415 969 8238
Date: Thu, 31 Dec 1992 07:52:17 GMT

What's a good "recommended" launch weight for a rocket powered by an
F100-4 Flight Systems motor?

--
Byron Reynolds (bbs.byron@tsoft.net)
From: CT80@music.mus.polymtl.ca (Steph)
Newsgroups: rec.models.rockets
Subject: Re: 8' rockets..
Date: 23 Dec 92 18:24:55 GMT
Organization: Ecole Polytechnique de Montreal

In article <1992Dec23.072420.1964@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:
>Roger.Wilfong@umich.edu (Roger Wilfong) writes:
>:
>: There is an organization the a Tripoli member, Tom Blazin (sp?), was trying
>: to start.  It is called 'The Black Rock Society' and is dedicated to
>: 'serious' (no big talkers allowed!) rocket development.  Again, I'll try and
>: find the address.
>
>The address is:   Black Rock Society
>                  PO Box 141
>                  Gerlach, NV  89412-0141
>
>Write Tom, at the above address. He may be able to point you in the right
>direction. According to him, there are a number of groups interested in, and
>working on, non-professional rockets.
>
>Bill
>.
>.

Thanks a lot!  Now this could prove to be very interesting.  Heck,
I might even get to see the rocket fly next time if it's not launched
oversea..


Steph.
Who needs a .sig?
From: 161685732@vill.edu (JOE PRYSZLAK)
Newsgroups: rec.models.rockets
Subject: Re: hot glue
Date: 2 Jan 93 17:58:00 GMT
Organization: Villanova University
News-Software: VAX/VMS VNEWS 1.4-b1

In article <1992Dec31.165046.1878@rsd0.rsd.dl.nec.com>, buzz@rsd.dl.nec.com (Buzz McDermott) writes...
>In article <85995@ut-emx.uucp>, miles@emx.cc.utexas.edu (Miles Abernathy) writes:
>|> I have only flown a small Estes rocket, the hobby store kind, but I was
>|> told on good authority (by a fellow who helps students put similar
>|> rockets together "all day long" at the school where he teaches) that you
>|> could use hot glue on the fins. I guess the motor burns out before the
>|> glue warms up.
> 
>Personally, I don't see the point to this discussion.  OK, so maybe (maybe not)
>you can use hot glue attaching fins.  Why would you want to :-)?  If you want 
>something better than white/yellow glue use 'gap-filling' cyano.  Stronger
>than white glue.  Dries fast (SUPER fast with accelerator).  Easy to use.
>Much less messy.  A little goes a long way.  No batteries/AC required.
> 
>If you don't like cyano, use 5 minute epoxy, mixing a tiny batch for each fin.
> 
>================================================================================
>= Buzz McDermott                Disclaimer: I speak for no one but myself. My  =
>= buzz@rsd.dl.nec.com                       advice is free and worth every     =
>= NAR   13559                               penny!!                            =
>= TRA    1785                                                                  =
>================================================================================
I never liked Cyano for gluing fins.  Never held very well.  Epoxy is good,
but the 30 minute kind gives you a much better hold.

The newest finishing trick I discovered is instead of spraying the rocket in
clear arcrylic spray to secure decals, spray the rocket in high gloss 
polyeurathane.  Make the rocket hard as stone.  Suffers almost no damage if the
recovery system fails/
Newsgroups: rec.models.rockets
From: ntaib@silver.ucs.indiana.edu (Iskandar Taib)
Subject: Re: FidoNet
Organization: Indiana University
Date: Sun, 3 Jan 1993 00:02:13 GMT

In article <30DEC199208355605@vx.cis.umn.edu> soc1070                          writes:

>I understand where he's comming from. My situation is that I have a
>temporary student account at the U of MN that gives me internet access.

>Someday my account will dissapear and i will be very sad :(

Check in soc.culture.celtic. There is a post titled something like 
"Internet access in the UK." Surprisingly there is a part about 
halfway down about a company in the US that offers modem-based inter-
net access. Fees aren't excessive - a one-time membership fee and a 
monthly fee and _no_ connect time fee if you live in a "class A city".

I'll repost the appropriate section here if there is interest. 

I also thought that Fidonet users had some access to News.. I've seen
a lot of postings from Fidonet.



-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: NTAIB@SILVER.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS                 !
From: paul@taniwha.UUCP (Paul Campbell)
Newsgroups: rec.models.rockets
Subject: Re: Other reloadables besides Aerotech? (Re: Info. about solid rocket-
Date: 26 Dec 92 06:10:24 GMT
Organization: Taniwha Systems Design

In article <1992Dec22.201612.9214@rsd0.rsd.dl.nec.com> buzz@rsd.dl.nec.com (Buzz McDermott) writes:

>Am I missing something?  Is there a way to exclude the delay grain if you're
>using electronic timers, etc.?  Should I just leave in the delay grain, 
>whatever length it is, and not worry about it?

If you're not using the delay on a non-reloadable the usual thing to do is to
remove the ejection charge and fill it 5-minute epoxy. On a reloadable I
fit it with a really long delay and leave it in (as a backup). Alternatively
you can do as you suggest and use a very short delay and no ejection
charge - make sure you fit all the delay insulators and O-rings.

On my first ever J flight I had a premature ejection (calling doctor Ruth ? :-)
caused by burn through in the delay that caused the ejection charge to go
off at ~100ft - it didn't stop there - whatever happened to the delay
causes a jet of flame to toast the insides of my motor mount and rocket
(out that little hole for the ejection charge) - it wasted the shock cord
first so the payload/noscone/chute came free and the bottom part kept on flying
straight as an arrow under power - in the end I got everything back with very
little damage (apart from my ego :-) and had to replace the motor tube (not
easy!). Moral of this story - use a delay element, or block that hole even if
you aren't using an ejection charge.

	Paul
-- 
Paul Campbell    UUCP: ..!mtxinu!taniwha!paul     AppleLink: CAMPBELL.P
"Finally after much thought he tied a dollar bill to the top of the tree, it
seemed to fit - after all it was the premier capitalist holiday, besides after
the 'fall' of communism a star didn't seem appropriate anymore ..."
From: CT80@music.mus.polymtl.ca (Steph)
Newsgroups: rec.models.rockets
Subject: Re: 8' rockets..
Date: 24 Dec 92 19:06:45 GMT
Organization: Ecole Polytechnique de Montreal

In article <1992Dec24.100504.21730@aio.jsc.nasa.gov> jackson@sn.jsc.nasa.gov writes:
>
>One may also contact
>Pacific Rocket Society
>Dept T 1825 N. Oxnard Blvd
>Suite 24
>Oxnard, CA
>93030
>
>The sell some books on liqid rockets which are interesting, and
>have a newsletter supposedly tho that may be ripoff because I
>sent them money for one and never got it. But they will send
>you the books.
>
>You likely ought to subscribe to High Power Rocketry to find out
>more:
>$25 / year
>P.O. Box 96
>Orem, UT
>84059-0096
>USA
>....................
>.
>.

Before I subscribe to anything I'll have to find out what they
are first.  I don't want to get into a club that builds rockets
using "A-G" engines.  They are very practical for model buildings,
but they just can't lift the weight we have.  Thanks for your
input, I'll check it out.


Steph.
Who needs a .sig?
Newsgroups: rec.models.rockets
From: soc1070                         
Subject: Re: FidoNet
News-Software: VAX/VMS VNEWS 1.41    
Organization: University of Minnesota CIS
Date: Wed, 30 Dec 1992 13:35:00 GMT

In article <1369@taniwha.UUCP>, paul@taniwha.UUCP (Paul Campbell) writes...
>In article <26DEC199201121721@vill.edu> 161685732@vill.edu (JOE PRYSZLAK) writes:
>>Can anyone tell me if there's a FidoNet message base that is dedicated to
>>model rocketry.  If not, would anyone be willing to help start one?
> 
>Why start another ghetto - there's already Compuserve & us - can't we just
>gateway r.m.r to/from Fido and make one bigger newsgroup?
> 
>	Paul

I understand where he's comming from. My situation is that I have a
temporary student account at the U of MN that gives me internet access.

Someday my account will dissapear and i will be very sad :(

I had an account on compuserve, but found that $12.50 an hour was to
much just for a forum & mail. Until they add modelnet to the flat-rate
package I'll steer clear of Compu$erve.

I have considered Fidonet, but I don't feel its a reliable way to move
information around. Basically, it comes down to paying long distance
bills. In a city, the gateway sysops get together and split phone
bills. But in smaller locations, where gateways get farther and farther
apart, you start relying on one person to forward your message. You
can combine fido and the usenet groups (I believe), but the sysop
has to be both on Fido and have an internet FEED (not just an account).

And, if you have an internet feed, who cares about fido?

What does all this have to do with rockets? Not much. However, most of
us realize that there is a problem in that there are two main groups
of people sharing information, but the groups can't communicate. IMHO,
thats bad for the hobby. (There are also other smaller groups, locally,
on GEnie and America Online, etc.). It would be nice if there were some
system whereby everyone could talk to eachother. I think it will be up
to the phone companies. Once there are digital phone lines to homes,
the cost of providing an internet gateway will be minimal and everyone
would have a node in their home. 

Sorry for the tangent

------
Tim Harincar				Millions long for immortality			
Central Minnesota 			who don't know what to do with
Association of Rocketry			themselves on a rainy Sunday 
soc1070@vx.cis.umn.edu			afternoon. -Susan Ertz
Newsgroups: rec.models.rockets
From: billn@hpcvaac.cv.hp.com (bill nelson)
Subject: Re: 8' rockets..
Organization: Hewlett-Packard Company, Corvallis, Oregon USA
Date: Fri, 25 Dec 1992 08:22:54 GMT

CT80@music.mus.polymtl.ca (Steph) writes:
: >
: >You likely ought to subscribe to High Power Rocketry to find out
: >more:
: >$25 / year
: >P.O. Box 96
: >Orem, UT
: >84059-0096
: >USA

: Before I subscribe to anything I'll have to find out what they
: are first.  I don't want to get into a club that builds rockets
: using "A-G" engines.  They are very practical for model buildings,
: but they just can't lift the weight we have.  Thanks for your
: input, I'll check it out.

The members of Tripoli do not use Model Rocket engines very much.
Most of their rockets use H and up. I believe that P engines are
the largest that have been used.

Bill
From: 161685732@vill.edu (JOE PRYSZLAK)
Newsgroups: rec.models.rockets
Subject: hot glue
Date: 24 Dec 92 01:46:00 GMT
Organization: Villanova University
News-Software: VAX/VMS VNEWS 1.4-b1

I recently had to buy a hot-glue gun to fix my macintosh.  I wanted to know,
since I now own the thing, how good is hot glue at hoding balsa fins onto
paper body tubes?

Also, any new news on the Estes E and F rockets?
Newsgroups: rec.models.rockets
From: buzz@rsd.dl.nec.com (Buzz McDermott)
Subject: Re: Other reloadables besides Aerotech? (Re: Info. about solid rocket-
Organization: NEC America, Radio Software Dept
Date: Tue, 29 Dec 1992 16:21:00 GMT

In article <Bzrs6r.477@usenet.ucs.indiana.edu> ntaib@silver.ucs.indiana.edu (Iskandar Taib) writes:
    This brings up another thing I've been wondering about. 

    How can one size of casing take both F and G reloads? The total impulse
    of one is twice as much as the other, so there must be twice as much pro-
    pellant in one grain than the other. Either they use two different pro-
    pellants with different "impulse densities" (impulse/volume) or they must
    have something take up the excess space. Is it a solid filler or is it 
    air?

The Aerotech 29/40-120 system uses 1, 2 or 3 propellant 'slugs' and cardboard
tube spacers. Nothing is ever left 'loose' in the casing.  This is the same
for delay elements.  You have thicker or thinner elements, depending on the
delay time, and cardboard tubing to take up the extra space.  The 18 and 24 mM
reload systems are handled in the same manner.  And by the way, there is twice 
as much propellant between the 29mm 'E' (40NS) and 'F' (80NS) reloads.
However, the 'G' reload is only 120NS, not 160NS.  It uses 3 of the propellant
slugs versus 2 for the 'F'.

The 'ISP' systems use a different approach.  There are a number of different
casing lengths available which use common end closures.  For example, there
are 4 different 29mm casing sizes available, providing 60 to 240NS of total
impulse potential.  There are also 4 38mm casings available, providing from 
240 - 600NS potentail total impulse.  With the ISP system, the casings always
have a full propellant load (1, 2, 3 or 4 slugs, depending on casing size).
The delay is handled the same as with the Aerotech system...different sizes
with small cardboard spacers when required.

There is generally more than one propellant formulation available for each
ISP casing size.  The BlackJack formula yields a motor with a little less
total impulse even though the total propellant size is the same as for 
White Lightning or Blue Thunder propellants.  For example, the BlackJack 
reload for the 29/180 casing is a 160NS 'G'.  The White Lightning reload
is the same size and is a 180NS, a 'baby H'.

I am only familiar with Aerotech and ISP RMS systems.  I don't know how those
from other manufacturers work.

================================================================================
= Buzz McDermott                Disclaimer: I speak for no one but myself. My  =
= buzz@rsd.dl.nec.com                       advice is always free, and gives   =
= NAR   13559                               constant proof to the old saying   =
= TRA    1785                               'you get what you pay for'.        =
================================================================================
From: cdt@sw.stratus.com (C. D. Tavares)
Newsgroups: rec.models.rockets
Subject: Re: hot glue
Date: 29 Dec 92 18:43:36 GMT
Organization: Stratus Computer, Inc.
NNTP-Posting-Host: rocket.sw.stratus.com

In article <23DEC199220462000@vill.edu>, 161685732@vill.edu (JOE PRYSZLAK) writes:
> I recently had to buy a hot-glue gun to fix my macintosh.  I wanted to know,
> since I now own the thing, how good is hot glue at hoding balsa fins onto
> paper body tubes?

Bloody awful.  First, it tends to make a gloppy mess, and even if it
doesn't, the glue is much too flexible after it sets.  Second, engines
usually get hotter than your hot glue gun, and your fins simply fall 
off in mid-flight.
-- 

cdt@rocket.sw.stratus.com   --If you believe that I speak for my company,
OR cdt@vos.stratus.com        write today for my special Investors' Packet...
Newsgroups: rec.models.rockets