Quantcast

75mm Reload Question

The Rocketry Forum

Help Support The Rocketry Forum:

Trenman

Well-Known Member
Joined
May 26, 2009
Messages
158
Reaction score
0
Is there a SPECIFIC reason that there is a threaded hole at the top of my AMW 75mm reload kit? Is this for an eye bolt?
 

WillMarchant

Well-Known Member
TRF Supporter
Joined
Jan 15, 2009
Messages
2,366
Reaction score
71
You'll find that many plugged closures are drilled/tapped for an eyebolt. The theory is that the motor mount is the strongest part of your rocket and you might as well harness to it. Having said that, an eyebolt isn't necessarily the only use. You can also use it for some form of forward motor retention...
 
Last edited:

ben_ullman

Well-Known Member
Joined
Jan 18, 2009
Messages
1,523
Reaction score
0
You'll find that many plugged closures are drilled/tapped for an eyebolt. The theory is that the motor mount is the strongest part of your rocket and you might as well harness to it. Having said that, an eyebolt isn't necessarily the only use. You can also use it for some form of forward motor retention...
CAUTION!! Some bulkheads have a tiny pinhole (like 1mm) at the bottom of the threaded portion going to the inside where the smoke grain goes. this is to relieve the air and make putting in large smoke grains easier. YOU MUST use aneyebolt in this case or run the risk of burning up your whole recovery area (im telling you this from experience) its can be a costly mistake! If you don't need it for recovery just stick a bolt or piece of threaded rod in there as a safe guard.

Ben
 

WillMarchant

Well-Known Member
TRF Supporter
Joined
Jan 15, 2009
Messages
2,366
Reaction score
71
Some bulkheads have a tiny pinhole (like 1mm) at the bottom of the threaded portion going to the inside where the smoke grain goes.
That's a good caution, Ben! Who does that with their casings? I haven't seen it before...
 

ben_ullman

Well-Known Member
Joined
Jan 18, 2009
Messages
1,523
Reaction score
0
That's a good caution, Ben! Who does that with their casings? I haven't seen it before...
I have a gorilla motor works BH that has it and AMW might since they are (cough) clones :p

It was the flight in my dads nike smoke. 76-7000 Super Polish Rojo. One of the greates boosters. Burned the TAC-9 and 75feet of bright yellow 1" TN into a nasty black ball of nylon. I wish I would have kept it. It was quite a conversation piece lol

Ben
 

Rocketjunkie

Addicted to APCP
Joined
Jan 19, 2009
Messages
4,203
Reaction score
397
The AMW 75/3500 case has a pinhole. The smoke grain O-rings do seal and it is not necessary to use a bolt in the closure. An eyebolt or threaded rod in the closure is needed to remove the bulkhead after flight.
 

WillMarchant

Well-Known Member
TRF Supporter
Joined
Jan 15, 2009
Messages
2,366
Reaction score
71
Thanks, Guys, I haven't flown AMW or Gorilla, so I appreciate the heads up!
 

ben_ullman

Well-Known Member
Joined
Jan 18, 2009
Messages
1,523
Reaction score
0
The AMW 75/3500 case has a pinhole. The smoke grain O-rings do seal and it is not necessary to use a bolt in the closure. An eyebolt or threaded rod in the closure is needed to remove the bulkhead after flight.
It wouldn't be bad insurance. I thought my Orings would seal too! They didnt!!

Ben
 

cjl

Well-Known Member
Joined
Jan 18, 2009
Messages
12,549
Reaction score
5
It wouldn't be bad insurance. I thought my Orings would seal too! They didnt!!

Ben
Were yours on an EX load? That's not really comparable to a commercial load (which should definitely seal).
 

ben_ullman

Well-Known Member
Joined
Jan 18, 2009
Messages
1,523
Reaction score
0
Were yours on an EX load? That's not really comparable to a commercial load (which should definitely seal).
why is it not comparable to a commercial load? I used the same exact casting tubes, orings, and bulkhead as a commercial load. and added an 1/8" cap of epoxy.

Plenty comparable.

Ben
 

n3tjm

Papa Elf
Joined
Jan 21, 2009
Messages
7,391
Reaction score
237
Location
Penns Creek, PA
Only the bulkhead for the 1700, 2500, and 3500 AMW motor has the pinhole. The 6000 and 7600 does not have one since they use a full diameter smoke.
 
Top