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I flew an N2220DM at LDRS. While it was great, it wasn't quite as loud/crackly as some others I have seen and this is consistent throughout Dark Matter loads. About 3/4 of the way through the burn it looks like a lot of the metals were slagged up on the inside of the nozzle and it spits it all out at once.

I'm not complaining, just genuinely curious if there's any insight as to where the variation in the sound comes from. Just the luck of the draw on how much of the metal makes it out at what point throughout the burn?

Braden
 
Any chance of a 54/1706 New Blue Thunder? It's my favorite propellant (beautiful flame, incredible performance) and I think it could kick some butt in that case.
 
I flew an N2220DM at LDRS. While it was great, it wasn't quite as loud/crackly as some others I have seen and this is consistent throughout Dark Matter loads. About 3/4 of the way through the burn it looks like a lot of the metals were slagged up on the inside of the nozzle and it spits it all out at once.

I'm not complaining, just genuinely curious if there's any insight as to where the variation in the sound comes from. Just the luck of the draw on how much of the metal makes it out at what point throughout the burn?

Braden
It’s a good question, I’ve noticed that myself and have wondered if it was dependent on the ambient atmospheric conditions. I have no other explanation at this time.
 
So to clarify, New Thunder is different than Super Thunder, which is more better than original Blue Thunder....
I need a scorecard. Or maybe a Thrustcard... :rolleyes:;):p
 
Does the new blue light as easily as the old blue? I like old blue in the sustainer for a multistage rocket.

I've had good experience with the G138 in clusters, they both light immediately, at exactly the same time.
 
SORRY FOR LONG POST.
I had another 18mm nozzle partial failure in a Quest motor... But may have picked up on something, I want to ask about:
How hard/brittle/pressure tolerant etc are the Quest clay nozzles? (Specifically compared to Estes BP nozzles..maybe, if you can.)

I have flown Estes for MANY years, but the Quest Q-jets for only the last ~year. So I am used to pushing in the igniter plug to hold the BP igniter. The quest igniter goes in differently (no big deal), BUT its held in by the tiny piece of heatshrink tube. To get the tube to hold the igniter, I have "gently" used the tip of the "toothpick" from my Swiss Army knife to help position the tube.
So my question: While I feel the force/pressure used positioning the tube is gentle ( MUCH LESS than that of the BP plugs); could it be enough to "stress crack" the end of the nozzle? Not visually damage or cracked. This then partially fails the nozzle at ignition of the motor. The off-axis thrust causes rocket instability, poor flight, etc.

With the new Q-jets, there are a number of other threads about nozzle issues. If the Q-jet nozzle is easier to subject damage to than PB nozzles, maybe it's self inflicted damage as the root cause.
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After I had a rocket that has always flown straight take an 80 degree turn I suspect a noozle failure like you have. I didn't use the tube stuffed into the noozle, just masking tape to hold the igniter in.

At home I examined nozzles on spent motors both Estes & Q-jet. Picking at them, the Q-jets noozle clay is a lot softer than the Estes. A wood skewer easily cuts into the Q-jet noozle and the clay just falls apart.
 
Man...MSRP of a 1706 reload is now 142.99. Even BMS pre-order price is now over 100. I remember when you could get a K550 for 60 bucks.
 
Last Saturday I flew a H210R with manufacture date of July 2001. The packaging still had its price tag on it. $15.95. Today it's $35.99. Unreal.
 
20 years ago we purchased a brand new Pontiac Grand Pre for 14k.
Ironic. I bought a 2002 Pontiac Grand Pre about 3 years ago for around 1,700. Lasted me 2 years and then the tranny went out at about 185,000. Dealer gave me 1,100 for the trade in towards my current vehicle.
 
On the subject of Dm loads , can we get a 98mm 4 grain load ?

I have suggested this to Gary a couple times in private chat :D. I told him I have a rocket that would be perfect to demo such a motor at a Red Glare or up near Buffalo.

I told him I need that motor on display next to my H45 and I65 casing in my office after I fire it :D
 
Are Aerotech 75/6400 and 75/7680 reloads no longer (or were they ever) crossroad certified for CTI hardware? I was reading old threads from 2017 after they were introduced and someone posted a crossroad matrix that included 5 and 6 grain motors. However the matrix on the Aerotech website only lists motors up to 75/5120. Is this the most up to date list to reference?
 
Are Aerotech 75/6400 and 75/7680 reloads no longer (or were they ever) crossroad certified for CTI hardware? I was reading old threads from 2017 after they were introduced and someone posted a crossroad matrix that included 5 and 6 grain motors. However the matrix on the Aerotech website only lists motors up to 75/5120. Is this the most up to date list to reference?
The original official crossload chart included those motors, future crossload charts did not. Apparently they were never certified.
 
interesting.

Question is, do they work? If so they could be flown as EX loads
They work just fine. I've seen at least 3 M1315s fly in CTI 5g casings just fine (including one at a NAR launch before the revised crossload sheet was released- oops).
 
The original official crossload chart included those motors, future crossload charts did not. Apparently they were never certified.

Cool, thanks for the info. I'd love to fly 5 and 6 grain stuff in my CTI hardware, but the 4 grain stuff should still be great as well.

Looks like I'll need to purchase a forward seal disk, for those who have used them, is it worth spending the extra $20 to get the stainless steel one? Is it easier to clean? The only other Aerotech stuff I've previously flown was 38 MM and besides some anodizing fading, the aluminum seal disk in that case seems to be doing fine...
 
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