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I'm trying but I'm addicted to 9v batteries and need that sweat taste in my veins. 🤩



You mean like a 13mm or 18mm? I figure as soon as I buy some Quick Dip, the motors will come with pyrogenic starters.

I have lots of smokeless gunpowder but no BP for a muzzleloader. Too much work (like a reloadable motor)...
I am thinking the easiest source of BP for this purpose may be a zero delay low power motor. No clay cap. Not sure if you need to use plastic instead of metal to scrape it out, obviously you don’t want to create any sparks, although I think this would be unlikely.

I got this from Walmart, but the grains were waaaaay to thick. An inexpensive mortar and pestle did the trick. Probably would work for chunks of propellant harvested from say a D12-0.image.jpg
 
Ejection Charge 12-Pack (rocketmotorparts.com)

1617816719795.png
One vial can do maybe, a hundred igniters? So a penny per.
Also see Chris M's postings:
Model Rocket Building: Upgrading Estes "Starter" Igniters, Part 1 TIP
Model Rocket Building: Upgrading Estes "Starter" Igniters, Part 2, TIP
A long while ago I tried to see if any gun shops here carry 4F powder.
They either said no or they don't carry it any more due to insurance requirements.
Found a couple of websites that sell it but only in bulk.
Maybe try make a few with your smokeless gunpowder and do some tests.
Or like I said empty a round or two.
Video, please.
 
What kind of glue did you use for installing the MM? I've found with even small rockets that wood glue (Titebond II) grabs too quickly so I've been using epoxy for installing MMs.

The Air Walker has a unique plastic MM that slides into the BT which has cut outs to fit the lugs and fins. The MM pieces together like the Redstone escape tower. I didn’t give it the proper respect and align the parts so it can fit into the BT and align the fins. My adult son was amused when I n00bed the tube.

E053A21A-FBBB-4F13-BBD9-DAC2428A8F43.jpeg
 
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I am thinking the easiest source of BP for this purpose may be a zero delay low power motor. No clay cap. Not sure if you need to use plastic instead of metal to scrape it out, obviously you don’t want to create any sparks, although I think this would be unlikely.

I got this from Walmart, but the grains were waaaaay to thick. An inexpensive mortar and pestle did the trick. Probably would work for chunks of propellant harvested from say a D12-0.View attachment 458798
I’m using Accurate 1680 which is about the finest powder I have.

4FE6AC3C-790E-4EC4-91A8-65568773599D.jpeg

Using stinky nail polish and the ball powder, does this look right?

View attachment trim.A80840B1-95D9-49B8-A861-10D672D21EAE.MOV
 
We were hoping that rechargeable Li-ion would work. They could be poor knock off batteries. They said they'll mail me replacements.
Also see post #3 in the YORF thread that just got posted. It mentions a recent change in the design of 9v. alkalines.
PS The lithium batteries they are recommending is the non rechargeable one. Don't know if there is a difference in voltage/amps between the two. I know that the old rechargeable batteries AAA - D were a nominal 1.2 v instead of 1.5 v.
 
Also see post #3 in the YORF thread that just got posted. It mentions a recent change in the design of 9v. alkalines.
PS The lithium batteries they are recommending is the non rechargeable one. Don't know if there is a difference in voltage/amps between the two. I know that the old rechargeable batteries AAA - D were a nominal 1.2 v instead of 1.5 v.
Note that for Energizer at least, their Ultimate Lithium AA and AAA are LiFeS2 and pack quite the grunt. Their Ultimate Lithium 9V, however, is LiMnO2 and has substantially lower max discharge.

AA : https://data.energizer.com/pdfs/l91.pdf
AAA : https://data.energizer.com/pdfs/l92.pdf
9V : https://data.energizer.com/pdfs/l522.pdf
 
Note that for Energizer at least, their Ultimate Lithium AA and AAA are LiFeS2 and pack quite the grunt. Their Ultimate Lithium 9V, however, is LiMnO2 and has substantially lower max discharge.
That's interesting, for the AA and AAA they actually specify 4A for a two second pulse, which is exactly what we care about, and a very good number for a single igniter. Is it enough for two? I wonder how many launches you could get out of a set of AAs.

For the 9V battery they don't specify pulse current at all.

For NiMH rechargeables they don't give pulse current but they do give a curve for 4A discharge: https://data.energizer.com/pdfs/nh15-2000gl1220.pdf. I had thought that NiMH AA batteries would be a great supply in my PS2 controller, but when I tried some recently I had no luck. However, those batteries are many years old, it's possible they're degraded or I need to do some refresh cycles to bring them back to normal. I need to do some experimenting with that.

The Lithiums have the advantage of not needing to worry about charging, and having extremely long shelf life. But they're expensive and single-use.
 
The Pulse Response looks like the quality measure we’re interested in. It’s curious that the AAA seem to perform better than the AA. As you previously mentioned, my simple volt meter is not able to capture the initial load on the batteries.

C822212B-8222-4BE0-87CD-A17BAB242175.jpeg

9FB14A50-9D40-4A86-989D-C633B7864ADE.jpeg
 
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That's interesting, for the AA and AAA they actually specify 4A for a two second pulse, which is exactly what we care about, and a very good number for a single igniter. Is it enough for two? I wonder how many launches you could get out of a set of AAs.

For the 9V battery they don't specify pulse current at all.

For NiMH rechargeables they don't give pulse current but they do give a curve for 4A discharge: https://data.energizer.com/pdfs/nh15-2000gl1220.pdf. I had thought that NiMH AA batteries would be a great supply in my PS2 controller, but when I tried some recently I had no luck. However, those batteries are many years old, it's possible they're degraded or I need to do some refresh cycles to bring them back to normal. I need to do some experimenting with that.

The Lithiums have the advantage of not needing to worry about charging, and having extremely long shelf life. But they're expensive and single-use.
I have done several launches up to clustered composite D's or single G's with my standard Estes E controller.
 
Apparently there was a redesign of some 9v. alkalines, prompting the recommendation by Aerotech for the 9v lithium battery. The Quest controller uses a 9v. battery.
It has an optional lead out for an external power source. You could also use that.
 
Some rockets can be sent on a booster in 23mph gust winds and come right back. Some will go on an adventure with a B6-4.


I ended up with an excess of C11-7. I think I bought them for the Loadstar and accidentally double ordered. That’s what happens when the motors have to travel by slow boat and I forget what I ordered.

I’m in the process of returning the Li-ion batteries. It’s a mystery why the voltage and current are the same but only the Amazon batteries will ignite the starters. How does one measure the quality of a battery other than V=IR? I’m also trying to convince my wife to share her nail polish for the starters but she says she doesn’t have any. Go figure...
I am impress with Astrocam video.
 
Are the motor mount centering rings paper or wood? My understanding is that for paper to paper, good white glue (not school glue) WHEN DRY is as strong as wood glue. For purposes of motor mount installation, white glue has two advantages over wood glue. Mainly, it allows a longer working time, less likely to grab prematurely. (That said, I test fit, test fit again, test fit again making sure I know exactly how far I am going to push in the mount, THEN apply the white glue and promptly and smoothly try to get it inserted in one smooth motion.) Since as opposed to fins, once you put the motor mount in it pretty much stays where you put it, the longer cure time for wood glue generally isn’t much of a disadvantage, especially since it is usually one of the first steps in building a rocket, and white glue cure time is generally less than paint cure time.

the second advantage (which I have read about but haven’t experienced, possibly because I don’t use wood glue for motor mounts) is that wood glue shrinks more, which may pucker the outer tube.

white glue has two advantages over epoxy for low power (I assume high power and maybe mid power has wood or possibly now with 3D printing plastic centering rings, white glue is a relative loser for anything but paper to paper.). 1. White glue is lighter than epoxy. 2. You don’t have to worry about ventilation, gloves, and annoying fumes with white glue.

YMMV.
good wood glue does not shrink....white glue shrinks more and will pucker your outside body tube. Will also warp fins when laminating paper to them....it is because of shrinkage. Had it happen to me many times before I read about wood glue not shrinking...never had it happen after that. The only thing I use white glue for is fin fillets and trailing edge sealant. Always use good white or wood glues and not that bargain basement stuff. That’s where the trouble begins.
 
good wood glue does not shrink....white glue shrinks more and will pucker your outside body tube. Will also warp fins when laminating paper to them....it is because of shrinkage. Had it happen to me many times before I read about wood glue not shrinking...never had it happen after that. The only thing I use white glue for is fin fillets and trailing edge sealant. Always use good white or wood glues and not that bargain basement stuff. That’s where the trouble begins.
I only use white glue (Elmer's) on cardstock, less swelling than yellow.

159580901_3877388812300207_4582414360192144493_n.jpg
 
Several new rockets on a perfect Hawaiian day with 5 altimeters and 1 Astrocam flight

After a month of windy days, finally had a perfect day with 7mph winds at 77F and 44% humidity. There were occasional gusts but nothing significant. This was a record 44pts launch day. The altimeters were hot and so were the cams. The only hiccup was at the beginning when one of the controller wires broke off, so we stripped and reattached. After fiddling with it, the continuity was consistent. I was using the starters with the ball powder and nail polish which worked great. I'm not sure why the screen went black during the Flip Flyer. Just a minor rendering error...

The Air Walker also worked great despite me n00bing the first one I bought at Estes Spring sale. I almost n00bed the second but figured out how to salvage it. The Biohazard (@neil_w's design) was very quick on the C11-5. In the end, the delay was too long. I think the shock cord wrapped around the fin during descent and broke off at landing. Easily glued together...

The Loadstar worked surprisingly well with the 18mm motors and payload cam. I wonder if I could put a composite motor in the sustainer... who dares me? This was the rocket that Cato'd with a D12-0, so I rebuilt it with the original motor mount.

The Honest John worked so well with the D12-5 that I decided I had to try it again with the E12-8. This is the replacement rocket after the first one ended up on the gym (white roof). I couldn't see it on the Loadstar video so perhaps the Parks did finally retrieve it.

00:00 Sundancer 4pts
01:16 Flip Flyer 5pts
02:43 Odd'l F-16 4pts
04:04 Little Joe I 210ft 6pts
05:00 Flight video
06:02 Air Walker 256ft 5pts
07:14 Biohazard 234ft 5pts
08:59 Loadstar 5pts
10:13 Flight video
10:45 Honest John D12-5 567ft 5pts
12:15 Honest John E12-8 989ft 5pts
14:05 Total 44pts!!!

 
Several new rockets on a perfect Hawaiian day with 5 altimeters and 1 Astrocam flight

After a month of windy days, finally had a perfect day with 7mph winds at 77F and 44% humidity. There were occasional gusts but nothing significant. This was a record 44pts launch day. The altimeters were hot and so were the cams. The only hiccup was at the beginning when one of the controller wires broke off, so we stripped and reattached. After fiddling with it, the continuity was consistent. I was using the starters with the ball powder and nail polish which worked great. I'm not sure why the screen went black during the Flip Flyer. Just a minor rendering error...

The Air Walker also worked great despite me n00bing the first one I bought at Estes Spring sale. I almost n00bed the second but figured out how to salvage it. The Biohazard (@neil_w's design) was very quick on the C11-5. In the end, the delay was too long. I think the shock cord wrapped around the fin during descent and broke off at landing. Easily glued together...

The Loadstar worked surprisingly well with the 18mm motors and payload cam. I wonder if I could put a composite motor in the sustainer... who dares me? This was the rocket that Cato'd with a D12-0, so I rebuilt it with the original motor mount.

The Honest John worked so well with the D12-5 that I decided I had to try it again with the E12-8. This is the replacement rocket after the first one ended up on the gym (white roof). I couldn't see it on the Loadstar video so perhaps the Parks did finally retrieve it.

00:00 Sundancer 4pts
01:16 Flip Flyer 5pts
02:43 Odd'l F-16 4pts
04:04 Little Joe I 210ft 6pts
05:00 Flight video
06:02 Air Walker 256ft 5pts
07:14 Biohazard 234ft 5pts
08:59 Loadstar 5pts
10:13 Flight video
10:45 Honest John D12-5 567ft 5pts
12:15 Honest John E12-8 989ft 5pts
14:05 Total 44pts!!!


11 feet short of a thousand! What’s your record altitude?
 
You took a risk with that E12 (Honest John) but hey successfully recovered. I surprise only 567 feet on a D12, is the Honest John "built" heavy? Know its weight?
 
You took a risk with that E12 (Honest John) but hey successfully recovered. I surprise only 567 feet on a D12, is the Honest John "built" heavy? Know its weight?
Yeah, I lost the first HJ on a E12-4. It woulda made it if the chute had opened so used a nylon this time. This was the vindication flight.

I used epoxy for fillets plus baffle. Weighs in at 167g. Rockets also don't seem to go as high here in the tropics.
 
11 feet short of a thousand! What’s your record altitude?

Good question. I believe it's the Hyper Bat at 1005ft. The scratch Black Brant IV went 951ft on a D12-5.



Almost 6 ozs, yes heavy. I meant E12 she would have blown out of the field....
I decided to try it after the D12 worked so well. The E12 landed about 50ft from the launcher. Like I said, it turned out to be a perfect day.
 
I decided to try it after the D12 worked so well. The E12 landed about 50ft from the launcher. Like I said, it turned out to be a perfect day.
It is amazing that you got back a rocket from 1000' on that small field. I once launched my Solar Warrior to roughly 1300' and it came down about 50 yards away from the pad on an exquisitely still day, but that was on a farm that had lots of room for recovery if things didn't go so well.
 
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