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View Full Version : Pop-and Go, Passport, Direct Staging Estes D Motors


snaquin
09-27-2006, 07:59 PM
What's your favorite method?

I removed the fins from the attached drawing. The booster airframe is 8" long. The black line is where the booster meets the sustainer. Both stages use Semroc LT-125 for the airframe. The blue tubing in both stages is a 5.5" piece of Semroc LT-115 that slip fits into the LT-125. The purple inside tube is a coupler made from LT-115 that is 3.5" long and has 2" bonded in the booster and the other forward 1" is what couples to the sustainer. The coupler is butted between the face of the forward centering ring in the booster and the face of the rear centering ring in the sustainer, the mentioned centering rings are positioned in such a way to accomodate the coupler. All the red parts are Semroc 24mm components.

If I can find an F100-0 to use for a booster motor and an F100-8 or 10 for the sustainer I'll eliminate the Semroc 24mm adapter parts in both stages ..... but I am currently planning to use Estes D12 motors in the booster and D12 or E9's in the sustainer because they are readily available.

So, what's your favorite staging method for this application? I can't tape the motor together as with direct staging. It's fairly small diameter airframe tubing with D motors in each stage. Should I extend the lower 24mm motor mount so the upper stage motor can plug directly into it or so the 24mm motor mount in the booster and sustainer when assembled butt up against each other? I don't think a 1/4" Passport hole in the 24mm mount would help much in this design since the coupler is so long, it doesn't seem like it would vent much before coming apart.

The original design used 29mm Mini-Max PB "F" motors and I think those were 7.75" long so my guess is the original was probably direct staged with the motors taped together. I have all the parts to build it (Thanks Semroc :D )and I only need to cut the sustainer fins and then I'm starting construction. Please don't ask what this rocket will be ..... it's a surprise (It's not the Sonic 36) ;)

Any and all suggestions are appreciated and I'd like to know about your experiences.

Thanks

.

ghrocketman
09-27-2006, 09:23 PM
I'd try what I call "fuse-staging"; have a piece of waterproof cannon fuse in the nozzle of the upper motor with the end touching the top of the booster motor grain. The fuse is consumed very quickly, and assures good ignition of the upper motor as it is in the nozzle touching the grain.
I have done this several times and it has worked great.

A Fish Named Wallyum
09-27-2006, 11:46 PM
"What do you use cannon fuse for?" (Bill asks, setting up this classic movie punch line..........)

Eagle3
09-28-2006, 08:02 AM
Pass-port and gap-staging worked fine for me until the B4-6 motors ran out. I've had two failures to ignite the sustainer with the B6-6. The last two MS flights of mine have been with the Estes direct staging using B6-6's and they staged fine. I think I'm going to start augmenting my sustainers with a piece of old sure shot for pass-port and gap-staging.

ghrocketman
09-28-2006, 09:31 AM
The old "thermalite based" sure shot is even better than cannon fuse for instant, almost guaranteed upper stage ignition.
Too bad thermalite wick is one of the numerous items the Gestapo, oops...I mean BATFE, has eliminated from the average rocket hobbyist's available items.

Eagle3
09-28-2006, 10:55 AM
Remember when you could get that stuff by the roll from HPR companies like LOC, THOY, and Magnum?

ghrocketman
09-28-2006, 11:49 AM
Yep, sure do & I'm not aware of any US Citizen hobbyist rocketeers using it for anything other than legitimate, safe hobbyist purposes either.
Go figure....

snaquin
09-28-2006, 06:18 PM
The old "thermalite based" sure shot is even better than cannon fuse for instant, almost guaranteed upper stage ignition.
Too bad thermalite wick is one of the numerous items the Gestapo, oops...I mean BATFE, has eliminated from the average rocket hobbyist's available items.

Thanks guys for the suggestions. It's been a good while since I've staged anything with black poweder motors and come to think of it I remember having success with fsi motors both direct staged with one wrap of scotch tape with the supplied thermalite igniter installed in the upper stage motor, and with a gap between the stages but still with a thermalite igniter in the upper stage. It would seem the consensus here is to have an igniter in the upper stage motor to .

Remember when you could get that stuff by the roll from HPR companies like LOC, THOY, and Magnum?

YES! I remember buying a 30M roll of the pink thermalite (slow-20 sec/foot) from Ross at an LDRS launch right off the back of his truck ..... and we all know we'll never see that happen again. Unfortunately I used the last of what I had around 1994. You may remember the Robby's Rockets cluster igniters were flash bulbs with several long whips of thermalite enclosed in teflon tubing with a shrink wrapped single whip attached to that and the bulb. I had some of those and just cut them up into single igniters until I ran out for good.

.

snaquin
09-28-2006, 07:26 PM
.....Too bad thermalite wick is one of the numerous items the Gestapo, oops...I mean BATFE, has eliminated from the average rocket hobbyist's available items.

..... and most recently eliminiated the ability to replenish any QuickBurst igniters to average rocket hobbyist's range boxes. I used David's QuickBurst "hot shot" low current igniters exclusively to ignite my clusters of Estes D12's because they fit perfectly in the nozzles and ignite a cluster of BP motors instantly.

I have enough to last me through the fall flying season with my current projects but after that I may have to look into dipping my own with one of the Magnelite pyrogen or similar kits, unless those disappear as well .....

.

Ez2cDave
08-02-2019, 10:26 AM
The old "thermalite based" sure shot is even better than cannon fuse for instant, almost guaranteed upper stage ignition.
Too bad thermalite wick is one of the numerous items the Gestapo, oops...I mean BATFE, has eliminated from the average rocket hobbyist's available items.

It wasn't Thermalite . . .

Centuri "Sure-Shot" igniters were Jetex wick with a piece of bare Nichrome wire wrapped around it.

FSI / Flight Systems igniters ( not the BP-100 Electrice Matches ) WERE Thermalite ( Nichrome wires spiralled around the wick, with reinforcing fibers ) !

Dave F.

Joe Wooten
08-03-2019, 07:50 AM
Remember when you could get that stuff by the roll from HPR companies like LOC, THOY, and Magnum?

I still have some from a roll I bought from THOY over 30 years ago. Not much, but it is still good.

snaquin
08-03-2019, 09:18 AM
I still have some from a roll I bought from THOY over 30 years ago. Not much, but it is still good.

The old stuff that I had from an LDRS years ago still worked fine too. I used so much of it back in the day. I’ll bet those Robby's Rockets cluster igniters I used had three or four one foot lengths all sheathed in teflon tubing burning up a few feet of the stuff with a single small H motor cluster flight.

;)

Ez2cDave
08-03-2019, 09:47 AM
CENTURI "Pass-Port" Staging . . .

Dave F.

snaquin
08-03-2019, 11:07 AM
It wasn't Thermalite . . .

Centuri "Sure-Shot" igniters were Jetex wick with a piece of bare Nichrome wire wrapped around it.

FSI / Flight Systems igniters ( not the BP-100 Electrice Matches ) WERE Thermalite ( Nichrome wires spiralled around the wick, with reinforcing fibers ) !

Dave F.

Awesome. Thanks for posting that Centuri detail Dave.

I have both a two stage and a three stage design saved in RockSim with available parts in my bins so this information will be helpful. I have in mind an Estes E16-0 for the booster but I will need to sim both versions off of a 72” rod or rail to see if three stages will work. I will post about it to a new build thread (when I start again on this LT-125 based rocket project).

LeeR
08-03-2019, 11:15 AM
Check out the gap staging on the new Boosted Bertha. It has vent holes in the booster’s centering rings to vent to the rear.

You can download the instructions from the Estes site from the Boosted Bertha page.

I built a Double Mini Max a few years ago that uses gap staging. I used the method of venting at the top of the booster, thru several small holes. They actually are drilled thru the coupler where it is glued into the booster. Staging an A10 to A10 looks almost instantaneous. The gap is maybe 1”, and I used a lengthened motor tube in booster to help direct the blast from booster motor into upper stage nozzle.

Ez2cDave
08-03-2019, 11:25 AM
CENTURI "Sure-Shots" & Thermalite . . .

Earl
08-03-2019, 10:20 PM
CENTURI "Sure-Shots" & Thermalite . . .


The photo identified as "1968 Sure Shots" is actually of 1973-era Sure Shot 'Dot' igniters, a redesigned Sure Shot developed when Centuri released their 13mm mini motors in early 1973.

The prior design Sure Shot (which was for 18mm motors) would not fit on the newly released mini motors, so they developed the ones shown in the sealed packet using a single tape disc (same size as parachute tape discs), which were the same diameter as the mini motors (.5 inch). Nice thing was, the tape disc size also fit the inside diameter of 18mm motors, so the new 'dot' ignitors were the new standard for both 13mm and 18mm motors.

The other photo showing an assembled Sure Shot actiually does appear to be an early version of the Sure Shot ignitor, probably from the late 60s.


Earl

Flash
08-04-2019, 07:30 PM
I also personally loved the Sure Shots. Whenever I did clusters back then, I would always use them.
The old Estes also worked good for me after a careful inspection and not damaging them during insulation. I set them in place and pushed wadding between the wires to hold them in place as was one of the recommendations back then. I believe the plastic plugs used today could damage a Estes igniter unknowing to the rocketeer. I do admit that I really don't have any problem with them but when it comes to clustering, I do have some concerns. Of coarse the new igniter can't really be trusted for clustering as compared to the old one.

But the Sure Shot was the better choice in my book anyway.

LeeR
08-04-2019, 10:25 PM
Of coarse the new igniter can't really be trusted for clustering as compared to the old one.

The new Estes starters can easily be enhanced. The clear coating is water-soluble. I soak them for about 30 minutes, and the coating turns gummy. It can easily be removed.

Then, they can be dipped in NC lacquer, giving them a nice little flame. I’ve got quite a few Quest Q2G2 igniters saved for clustering, but the starter could be enhanced further with a pyrogen mixed with NC lacquer and should be a very good cluster igniter. Firefox Enterprises in Idaho is a good source for a variety of pyrogens.

http://www.firefox-fx.com/ignition.htm