Quantcast

L2 Project: WM Drago 4 "EX-1127"

The Rocketry Forum

Help Support The Rocketry Forum:

Theory

Well-Known Member
Joined
Nov 30, 2018
Messages
729
Reaction score
447
Cool

I’m using 2K clear satin on the silver. Used the gloss on the nose cone and fins. Came out very well
 

Handeman

Well-Known Member
TRF Supporter
Joined
Jan 18, 2009
Messages
7,730
Reaction score
324
Location
Stafford, VA
Hope your silver works. I've tried several different brands and methods. I won't use silver/chrome paint again.
 

Theory

Well-Known Member
Joined
Nov 30, 2018
Messages
729
Reaction score
447
---small update---

conducted ground tests of the recovery system yesterday. 2.0 grams for the booster and .5 grams for the nose cone worked very well. I could likely use .4 or even .35 grams for the nose with equally good results.

used two 2-56 pins in the booster and two in the nose.

the first flight is scheduled to take place at NOVAAR later this month. the motor will either be an AT I300 or Loki I405. will be a "game time decision" as i will like load both.
 

crossfire

Lifetime Supporter
TRF Lifetime Supporter
Joined
Jan 16, 2011
Messages
4,270
Reaction score
427
A half gram for drouge? I would use at last 1.5 grams. Heck a AT motor has 3/4 gram
 

Theory

Well-Known Member
Joined
Nov 30, 2018
Messages
729
Reaction score
447
no, .5 gram for the nose (HED). really only need to presurize the top portion of the 6:1 nose cone as the electronics bay come a solid 3+ inches into the bottom of the nose cone.

looks like i didnt explain that as well as i should have. too early int he morning LOLz
 

FMarvinS

Well-Known Member
Joined
May 27, 2015
Messages
428
Reaction score
69
I agree with crossfire. O.5 gm is too little even for HED. I have a Wildman 3 inch Punisher and another 4 incher with HED. Both use three 2-56 shear pins to the nosecone. How extended was the kevlar cord pulled out on ground testing? I'd suggest that the chute plus 75% of the cord or more is a positive ground test (as long as the cord is not too taut which could result in too large a charge and cord separation from the cone). For each of my above HED deploy rockets, I use 1.5 gms. Also, friction can arise between the NC bay and the inside of the cone; so, I usually wipe down these surfaces with a small amount of a mild car de-greaser (from autozone) on a paper towel to diminish this resistance prior to placing the shear pins. Finally, if there are any questions about how to attach the laundry for HED-see the HED section on Wildman's site under the "downloads" button. Good luck!

Fred, L2
ICBM, S.C.
KG4YGP
 

Theory

Well-Known Member
Joined
Nov 30, 2018
Messages
729
Reaction score
447
interesting...

had full extension using a 15' Rocketman 3 look kevlar cord.

if the weather improves i will set it all up again and document it.
 

crossfire

Lifetime Supporter
TRF Lifetime Supporter
Joined
Jan 16, 2011
Messages
4,270
Reaction score
427
I probably would use 2 grams in each section.
 

Theory

Well-Known Member
Joined
Nov 30, 2018
Messages
729
Reaction score
447
I probably would use 2 grams in each section.
Need to as why you would recommend that.

2 grams cleanly separated and reached near full extension of the harness (20' OBH three loop) for booster. talking about 20" of 4" air-frame with 2 2-56 pins. not even factoring in the unfilled portion of the 54mm motor mount.

why would I ever need the same charge for a nose cone? that math just doesnt work. we are talking about significantly less volume with a large portion taken up by the chute, harness, nomex etc.
 

crossfire

Lifetime Supporter
TRF Lifetime Supporter
Joined
Jan 16, 2011
Messages
4,270
Reaction score
427
There you go. 1.5 and 2 grams
 

Theory

Well-Known Member
Joined
Nov 30, 2018
Messages
729
Reaction score
447
due to the very low altitudes for each flight - 1000' ish, i went with single deploy.

the first time around i went with the 2 grams that i ground tested with. it worked but was very lazy; not as energetic as it looked during the tests.

due to weathercocking it lost a lot of altitude (the flight on the I300 was only 791 feet. i was expecting almost 900) and as such i was able to clearly view the deployment event. it is possible that the lazy deployment was the result of a fair amount of horizontal velocity at the time the charges went off.

went with 2.5 grams for the second flight on the I405 and that was perfect. I will be using this for future flights.
 

Latest posts

Top