AeroTech Open Thread

Onebadhawk
Advertise with us
madcow rocketry
The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
We're having difficulty with ignition of a D13W in an 18/20 case. We got the first one to light on the 2nd try. But the second one has gone thru 2 ignitors and still hasn't lit. Figured we must be doing something wrong.

We have triple checked and the ignitor is in the slot and is pushed ALL the way up to the top. The ignitor wire was secured with masking tape to keep it from moving down. Each time the ignitor and it's pyrogen burn without igniting the propellant.

I realize that this motor has a small nozzle throat diameter requiring the ignitor to be small with a limited amount of pyrogen. But we've had 100% ignition reliability on a dozen firings of our 24mm E6-RCT reload which has an even smaller nozzle.

Any suggestions or advice?
 
Bruce said:
We're having difficulty with ignition of a D13W in an 18/20 case. We got the first one to light on the 2nd try. But the second one has gone thru 2 ignitors and still hasn't lit. Figured we must be doing something wrong.

We have triple checked and the ignitor is in the slot and is pushed ALL the way up to the top. The ignitor wire was secured with masking tape to keep it from moving down. Each time the ignitor and it's pyrogen burn without igniting the propellant.

I realize that this motor has a small nozzle throat diameter requiring the ignitor to be small with a limited amount of pyrogen. But we've had 100% ignition reliability on a dozen firings of our 24mm E6-RCT reload which has an even smaller nozzle.

Any suggestions or advice?
Click to expand...
Try roughing up the slot in the grain with a knife or fingernail file.
 
I'm not sure if this is the right thread to ask this on, but does anyone have experience with the M1340 and whether one can bond a hardpoint for recovery hardware into the forward bulkhead? (where a charge well would normally be located).

This thread has a great photo, as do the instructions, and it sure looks like a solid attachment point, but I'm not sure.

https://www.rocketryforum.com/threads/m1340w-dms.149312/
Thank you -Greg
 
ghuber said:
I'm not sure if this is the right thread to ask this on, but does anyone have experience with the M1340 and whether one can bond a hardpoint for recovery hardware into the forward bulkhead? (where a charge well would normally be located).

This thread has a great photo, as do the instructions, and it sure looks like a solid attachment point, but I'm not sure.

https://www.rocketryforum.com/threads/m1340w-dms.149312/
Thank you -Greg
Click to expand...

The M1340 DMS motor comes with an aluminum Forward Closure that has a 3/8-16 threads built into it..

Tony
 
Mea culpa, I realize I mixed up the M1340 DMS (98mm) and the M1350 DMS (75mm). Is the M1350 the same in terms of having the threaded aluminum forward closure? Also, does anyone have experience using it for mounting recovery hardware? Thanks again.
 
ghuber said:
Mea culpa, I realize I mixed up the M1340 DMS (98mm) and the M1350 DMS (75mm). Is the M1350 the same in terms of having the threaded aluminum forward closure? Also, does anyone have experience using it for mounting recovery hardware? Thanks again.
Click to expand...
Yes.
 
ghuber said:
Mea culpa, I realize I mixed up the M1340 DMS (98mm) and the M1350 DMS (75mm). Is the M1350 the same in terms of having the threaded aluminum forward closure? Also, does anyone have experience using it for mounting recovery hardware? Thanks again.
Click to expand...

Using the threads on an aluminum Forward Closure is the strongest anchor point on our rockets. You still need to take some precautionary steps...

1. Retain the motor to keep if from falling out. Aft motor retainer or other retention or held in via those same threads to an internal bulkhead.
2. You also need to keep your attachment point Forged or welded eye bolt or eye nut..from unscrewing itself. Yes it CAN and DOES unscrew it self. Jam nuts or other restraining methods work.

20210421_083902.jpg

Tony
 
I just noticed the G71R for the 29/40-120 is out of production. Is that coming back? Maybe something more G138-style?
 
CarVac said:
I just noticed the G71R for the 29/40-120 is out of production. Is that coming back? Maybe something more G138-style?
Click to expand...
The G71-xR RMS reload kit for the AT 29/120-40 hobby case has been out of production since circa 2018 I believe, withdrawn due to problems with the delay element's unreliable timing. There is still a single use version of the motor, the 29mm G77-xR. I'm unaware of any effort to replace the RMS version.

Good skies,
GlueckAuf
 
GlueckAuf said:
The G71-xR RMS reload kit for the AT 29/120-40 hobby case has been out of production since circa 2018 I believe, withdrawn due to problems with the delay element's unreliable timing. There is still a single use version of the motor, the 29mm G77-xR. I'm unaware of any effort to replace the RMS version.

Good skies,
GlueckAuf
Click to expand...
Karl has been working on and off on a core burning version of the G71R. No timeline for certification yet.
 
I have a K2050 I plan on using this weekend. I opened the kit today to do the grain bonding. I realize the Aerotech grain bonding instructions are generic, but they do mention putting a grain spacer o-ring between each grain. This reload kit didn't come with grain spacer o-rings. Am I missing them or this reload supposed to not have them?
 
I may have answered my own question, when I dry fit the grains, they are actually too long. No way o-rings would fit between them. Even without o-rings, the forward seal disc doesn't seat into the liner. the grains come right to the end of the liner.

So, I guess second questions would be, assuming there are not supposed to be grain spacer o-rings, can I sand the end of one of the grains to get the forward seal disc to fit?
 
mtnmanak said:
I may have answered my own question, when I dry fit the grains, they are actually too long. No way o-rings would fit between them. Even without o-rings, the forward seal disc doesn't seat into the liner. the grains come right to the end of the liner.

So, I guess second questions would be, assuming there are not supposed to be grain spacer o-rings, can I sand the end of one of the grains to get the forward seal disc to fit?
Click to expand...

Yup
 
This may have been discussed earlier...and I didn't search too hard. NAR magazine shows the new 24mm QJets on the back and I like what I see. I expect to burn a pile of them when I can get some. Those are White Lightning propellant, so are there some with Black Jack propellant, like the 18mm QJets, on the way with a little less kick and longer burn time?
 
DigBaddy said:
This may have been discussed earlier...and I didn't search too hard. NAR magazine shows the new 24mm QJets on the back and I like what I see. I expect to burn a pile of them when I can get some. Those are White Lightning propellant, so are there some with Black Jack propellant, like the 18mm QJets, on the way with a little less kick and longer burn time?
Click to expand...
Not yet on the way but those are certainly a future possibility.
 

Similar threads

Valkyrie Recovery Systems
Valkyrie will be going to NSL 2024!
Replies
2
Views
215
Valkyrie Recovery Systems
Valkyrie Recovery Systems
overklock
Aerotech G-force Build Thread - WIP
Replies
12
Views
2K
gldknght
gldknght
Dane Ronnow
Build thread: Aerotech HV Arcas
2
Replies
43
Views
5K
Dane Ronnow
Dane Ronnow
Bruiser
RIP IQSY Tomahawk
Replies
3
Views
1K
waltr
W
fyrwrxz
  • Locked
The end of the Never Ending Story
2
Replies
46
Views
4K
OzHybrid
OzHybrid

Latest posts

Back
Top