What did you do rocket wise today?

[NTP2]

I found out where the EX people get their AP…

Ewwww

Ps I just realized that he said nitrate not perchlorate, I need to go get ears checked…

 

[berlinetta]

Yesterday, I used a nib file to file down the runs on my 5.5" Bullet. I also added another coat of clear and all scuff marks are gone. It's not perfect, but I'm calling it good. Decals go on tomorrow.

 

[berlinetta]

Spent some time testing the Altus Metrum EasyMini v3.0 to simulate my anomalous flight and lawn dart last weekend with the 38mm “The Lawgiver”.

I sent some basic info to the Altus Metrum “contact us” page and got speedy replies back. Since I’ve not found the rocket to check the physical evidence, I’ve only been able to give them flight behaviour observations.

The flight was on a Pro24 sparky G100. Good launch but quickly vectored right to about a 45 degrees climb then flattening out at about an estimated 800 feet. Watched it come in ballistic in the distance, fully intact, so both the apogee event and the main event failed to either ignite or to shear the single 2-56 nylon shear pins for the lower airframe or the nose-cone separation. Both BP charges were 0.35gms (ground tested well with 0.25gms), both BP ignitors were MJG Technologies J-Tek 7 eMatches, the battery was a Dualsky ECO 520.1S 3.7V LiPo.

After contacting the Altus Metrum guys, the conclusion regarding the altimeter functionality was that:

• The EasyMini would still have detected the launch (uses barometric sensing) despite the lower than expected apogee.
• The actual apogee should still have triggered the apogee ignition. Altus have reviewed a flight log where the apogee was only 35m above ground and it still triggered.
• The main (set to 700feet) should still have triggered, either at that altitude or a short duration after the apogee ignition if the actual apogee was lower than the setting for the main. They do this to ensure each igniter gets sufficient charge to work and to protect the airframe from the stresses of a simultaneous drogue and main deploy.
• They advised that my LiPo might have had a discharge protection circuit built into it which may have stopped the ignitors from getting sufficient current to fire. Their recommendation is to either use their special LiPos or a 9V battery.

So, to explore the theory that maybe the LiPo failed to fire the igniters, I’ve performed two ground tests with a spare EasyMini v3.0. I used the same type of set-up as the flight:

• One 1S Dualsky ECO 520 battery (1.92Wh, 3.7V, 25C).
• Both tests used a pair of MJG Technologies J-Tek 7 eMatches fitted to the Apogee and Main outputs. All were cut to the same lengths as was used in the Av Bay, and resistance checked to between 1.2 and 1.4 Ohms.
• One test was with the Lipo battery fully charged at 4.0V, as seen on the charger control screen and as reported by the EasyMini beeps.
• The other test was with the battery reporting 3.8V (EasyMini beeps only).
• Testing was done in my vacuum food-saving tupper-ware box, the air extracted by hand pump.
• In both tests, the apogee and main ignitors successfully fired at approximately the points they should have, so no apparent firing restriction from the LiPo.

View attachment 635805 View attachment 635806 View attachment 635807

I can't even get my laptop to see the Easy Mini. I have XP Pro, so I'm not sure if I'm connecting the altimeter to the laptop wrong. I attach it prior to turning it on

 

[RiffD]

Sanding, sanding, sanding....

Also crunching numbers on thurstcurve, OR, and crossing that with research on TRF. AKA gone done the data rabbit hole.

 

[John Kemker]

Two rocketry-related tasks accomplished today:

1) Shot Createx White Sealer over the fubar on one of my Nike Smoke fins. I didn't properly mask off the yellow fin when I painted the rest of the fins red and got overspray. White Sealer covers it up and if the weather cooperates tomorrow, I properly mask and shoot yellow again.

2) Finally managed to convert my Level 3 video CD to an MP4 and upload it to YouTube. The preview screen shows Tim Eiszner smiling for the camera.

 

[teepot]

The bending and that one gap make it look like a white aurora.

You will like this one. I took it October of 2022. This was a SpaceX one. We watched it until stage separation.

 

[boatgeek]

That's a great photo! Is that a lunar eclipse in the middle?

 

[jmasterj]

That's a great photo! Is that a lunar eclipse in the middle?

It looks to me like the darker part of the moon is just brighter than normal - look how bright the light part is.

 

[jqavins]

Sometimes, one's immediate vicinity is lit up at night by moonlight; under the right conditions, one can see the dark side of the moon by Earthlight. This looks like it was a long exposure, which would accentuate that.

 

[boatgeek]

It looks to me like the darker part of the moon is just brighter than normal - look how bright the light part is.

Sometimes, one's immediate vicinity is lit up at night by moonlight; under the right conditions, one can see the dark side of the moon by Earthlight. This looks like it was a long exposure, which would accentuate that.

Earthshine makes a lot of sense. Thanks!

 

[jmasterj]

Talked to my L3CC advisor about my L3 project, considered a few changes with him.

 

[John Kemker]

Sanded on the DRM fins to smooth them out and added some more wood glue for fillets.

Received my 75/6000 snap-ring case from @manixFan via UPS today. VERY happy with it!

 

[kuririn]

AIM-54A Phoenix.
Five down, one more to go.

 

[Cape Byron]

You have to laugh at tracking. USPS says the parcel has left Sydney.

Australia Post says the parcel is awaiting clearance in LA.

Lady at the post office says “Come and collect your f/-$ing parcel that’s sitting here”.

 

[SolarYellow]

Cleaned out the third local Hobby Lobby of clearance motors.

 

[Hobie1dog]

Went through some more old HPR magazines.

 

[cwbullet]

printed a fin can

 

[lakeroadster]

Swing Test 4X.... More Here

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[krislhull]

received an order from AC Supply today of a Big Der Red Max and a Doorknob. Upon opening the box, I found both kits had crushed tubes.... Now to contact AC Supply...

 

[goose_in_co]

In the continuing Expedition Saga...

The launch lugs are on and aligned, and the whole thing is now in primer.
It will need some more CWF for what the primer will show, and then another coat of primer.

 

[teepot]

You will like this one. I took it October of 2022. This was a SpaceX one. We watched it until stage separation.View attachment 636453

I took this picture with my phone set on night mode. The visible Moon was the large crescent. The picture showed more of the Moon than I could see with the naked eye. To me it looks like a Romulan Warbird attacking the Enterprise.

 

[Voyhager3]

Was fitting the SS together when the booster got stuck in the AF…
Now I get to cut the last foot out and re-build for tomorrow…

 

[jqavins]

Was fitting the SS together when the booster got stuck in the AF…
Now I get to cut the last foot out and re-build for tomorrow…

I try not to complain about unclear initialisms, and to just figure them out. But I'm stumped. How does a Social Security booster get stuck in antifreeze?

 

[NTP2]

I try not to complain about unclear initialisms, and to just figure them out. But I'm stumped. How does a Social Security booster get stuck in antifreeze?

Well it was bad antifreeze and it froze!

 

[NTP2]

This was last weekend but I got dragged into the local sports store by my brother and saw this, is it an use as a BP substitute for rocketry?

 

[John Kemker]

This was last weekend but I got dragged into the local sports store by my brother and saw this, is it an use as a BP substitute for rocketry?View attachment 636672

Maybe.

It can be used, but:

1) It has to be confined tightly. No loose powder in your charge well.
2) You may have to use more triple se7en than you would BP. Test to make sure.

Those with more experience than I using BP substitutes should join in the conversation and will have more specific info than I.

 

[Art Upton]

This was last weekend but I got dragged into the local sports store by my brother and saw this, is it an use as a BP substitute for rocketry?View attachment 636672

It can work as John stated, but unless your careful , it can fail when BP sub does not burn fast due to confinement leaks or slow burns for other reasons. I have both, tested both and I will stick to BP.

 

[SolarYellow]

Cleaned out the third local Hobby Lobby of clearance motors.

Went by the first HL to see if they'd restocked any clearance motors. They had not. However, there were a couple kits that were marked "reduced" with orange tags that had the original price on them. I took them up to the register to ask if that was a mistake or meant to be that way, explaining that all the other clearance rocket stuff was 50-off. The girl said it was an error, those were supposed to be 75-off. So I got two Long Rangers and a Baby Bertha for $8.93 total, out the door. Hoping there are enough straight fins to make one good Long Ranger fin can.

 

[RokitFlyr]

This was last weekend but I got dragged into the local sports store by my brother and saw this, is it an use as a BP substitute for rocketry?View attachment 636672

 

[rharshberger]

Requires very careful and consistent containment, and plenty of ground testing to get consistent results. BP substitutes are actually a type of smokeless powder and as such require confinement to build consistent pressure and an even burn unlike BP, BP is much easier and more reliable for our hobby purposes.