EZI 65 build tips

EZI 65 build tips

Post by Tom Binfor » Sun, 08 Feb 1998 04:00:00



I have seen MANY EZI 65 failures, almost always an aerodynamic shred
when using motors as small as an I435.  Failure is almost always due to
the fins fluttering and breaking off outside the body tube.  If you
replace the fins with G-10 fiberglass or laminate fiberglass on both
sides of the fin (easier to do before installation) an otherwise
unmodified EZI will survive at least a K550

 
 
 

EZI 65 build tips

Post by John H. Cato, Jr » Sun, 08 Feb 1998 04:00:00


Quote:

> I have seen MANY EZI 65 failures, almost always an aerodynamic shred
> when using motors as small as an I435.  Failure is almost always due
> to the fins fluttering and breaking off outside the body tube.  If
> you replace the fins with G-10 fiberglass or laminate fiberglass on
> both sides of the fin (easier to do before installation) an otherwise
> unmodified EZI will survive at least a K550

Welcome, Tom!!  Good to have you 'here'.

[for the RMR crowd, let me take the pleasure of introducing Tom Binford
to you folks.  Tom is the man of 'Cloudbuster' fame -- TRA number 6xx
(something?) -- and been 'around the block' a few times -- trying for
some of the TRA altitude records going back to Black Rock II in 1990.
Tom has 'pushed the edge' several times (I'm sure Tom Allen would fall
in love with him <g>) and knows whatof he speaks.  If it's 'bust butt',
Binford probably has been there and could tell you a few 'hangar
stories'.]

Again, good to have you with us, Tom.

-- john.

 "Once you give up your ignorance, you can't ever get it back."
                                                      Unknown

 
 
 

EZI 65 build tips

Post by Tom All » Sun, 08 Feb 1998 04:00:00


Howdy Tom
  I totally agree about fin problems. It would take a hell of a motor to
crush an airframe. I bought an EZI 65 & after looking at the fins
decided that they probably wouldn't get along with me. I could make g-10
fins but it would take one hell of a motor to make it go. I can't afford
3" motors. I am into altitude attempts. As I stand I have flown only 2
"J" motors. The first one for my Cert 2 flight & the second one at NTHP
98 for a new "J" class altitude record. Both flights were on Aerotech
J-350s. Very nice motors but only 700ns. I may have to slightly lengthen
my rocket, but I think it will go higher on some radical Kosdon 38mm
motor with closer to 1280ns. I hear rumors about a J 1500. Should take
off pretty fast.
Tom Allen
extreme rocketeer

 
 
 

EZI 65 build tips

Post by Chuck Mi » Mon, 09 Feb 1998 04:00:00


Quote:

>Howdy Tom
>  I totally agree about fin problems. It would take a hell of a motor to
>crush an airframe. I bought an EZI 65 & after looking at the fins
>decided that they probably wouldn't get along with me. I could make g-10
>fins but it would take one hell of a motor to make it go. I can't afford
>3" motors. I am into altitude attempts. As I stand I have flown only 2
>"J" motors. The first one for my Cert 2 flight & the second one at NTHP
>98 for a new "J" class altitude record. Both flights were on Aerotech
>J-350s. Very nice motors but only 700ns. I may have to slightly lengthen
>my rocket, but I think it will go higher on some radical Kosdon 38mm
>motor with closer to 1280ns. I hear rumors about a J 1500. Should take
>off pretty fast.
>Tom Allen
>extreme rocketeer

Tom, I have seen some of the 38mm Kosdon motors - pretty radical!  Also,
remember that Aerotech should have their 38mm 9-Grain J420 (?) certified late
spring.  Rumors put it in the 1080ns range with a sustantial burn time.

Chuck Mies

NAR #70811                              Tripoli #5626
Level 1                                 Level 1

Kloudbusters
http://www.kloudbusters.org/

 
 
 

EZI 65 build tips

Post by Bill Nels » Mon, 09 Feb 1998 04:00:00


: Howdy Tom
: 3" motors. I am into altitude attempts. As I stand I have flown only 2
: "J" motors. The first one for my Cert 2 flight & the second one at NTHP
: 98 for a new "J" class altitude record. Both flights were on Aerotech
: J-350s. Very nice motors but only 700ns. I may have to slightly lengthen
: my rocket, but I think it will go higher on some radical Kosdon 38mm
: motor with closer to 1280ns. I hear rumors about a J 1500. Should take
: off pretty fast.

Take of fast, yes.  Go higher, not necessarily.  Most HPR rockets need
slower burning motors for maximum altitude.

--

 
 
 

EZI 65 build tips

Post by Tom All » Mon, 09 Feb 1998 04:00:00


Howdy Bill
 How many altitude records have you set? I know about fast burn slow
burn & newton seconds. Build a few set some records.
Tom Allen
extreme rocketeer

 
 
 

EZI 65 build tips

Post by Mike Ban » Tue, 10 Feb 1998 04:00:00


Quote:

> Howdy Bill
>  How many altitude records have you set? I know about fast burn slow
> burn & newton seconds. Build a few set some records.
> Tom Allen
> extreme rocketeer

Tom:

Your remarks are really uncalled for.  I respect and appreciate your
"extreme flight" attitude, and usually lean in that direction myself.
However, Bill's post was polite, well intentioned, and scientifically
accurate.  The laws of physics apply even to extreme rocketeers.
Hopefully you won't get too***y about that altitude record and get a
swelled head.  Come on back down to earth buddy!

Regards,
Mike Banz

 
 
 

EZI 65 build tips

Post by Yves » Tue, 10 Feb 1998 04:00:00


Quote:

>Your remarks are really uncalled for.  I respect and appreciate your
>"extreme flight" attitude, and usually lean in that direction myself.
>However, Bill's post was polite, well intentioned, and scientifically
>accurate.  The laws of physics apply even to extreme rocketeers.
>Hopefully you won't get too***y about that altitude record and get a
>swelled head.  Come on back down to earth buddy!

I have no problem with Mr. Allen's need for speed and altitude.  I do
have problem however if this "extreme" attitude comes with the idea
that one can scoff at the safety codes.

--
Yves

 
 
 

EZI 65 build tips

Post by Tom All » Tue, 10 Feb 1998 04:00:00


Howdy Yves
 What  safety codes am I violating. I have never had any "problem" with
LCOs or RCOs. Most of them are impressed with my rocket construction &
or motor selection. My cp/cg is questioned but has always been OK. I
have had some rockets crash. Arrest me & take me to jail.
Tom Allen
extreme rocketeer

 
 
 

EZI 65 build tips

Post by Yves » Tue, 10 Feb 1998 04:00:00


Quote:

>What  safety codes am I violating. I have never had any "problem" with
>LCOs or RCOs. Most of them are impressed with my rocket construction &
>or motor selection. My cp/cg is questioned but has always been OK. I
>have had some rockets crash. Arrest me & take me to jail.

Tom, you really should think of taking things less personally.  I
wasn't aiming this at you specifically ... if you follow the safety
codes, more power to you.

--
Yves

 
 
 

EZI 65 build tips

Post by Bill Nels » Wed, 11 Feb 1998 04:00:00


: Howdy Bill
:  How many altitude records have you set? I know about fast burn slow
: burn & newton seconds. Build a few set some records.

I am not interested in setting records. I like my rockets easy to
recover.

However, that does not keep me from being interested in the theories
behind maximum performance.

--