Please Post VIDEO'S if you got em .

[Mumbles]

The thing that throws me is that the poof just doesn't seem big enough to be an ounce and a half of lift.

[cplmac]

There was nothing on top of it. The mortar was only four inches tall at that point, and there was nothing but air over it, I found the shell wrap about fifty feet away.

[WarezWally]

What a shit night, had one great opportunity to shoot what i wanted and everything sucked, from my rockets to my shells.

 

Had 2 rockets fail on me tonight:

 

This one was a 1lb made with my new swanky pyrotooling, fuel was some crap i had laying around that was fairly slow. Any ideas what went wrong? This one had a 50g dummy header. Was not happy with the nozzle (was crumbly and and a bit thick) and it crumpled the tube a bit.

 

 

Looks to me like a blowout

 

This one was made with my Chinese tooling (with the nozzle drilled out), tube recovered intact and is perfect, nozzle held out well. Was 1lb with no header. Same fuel as above.

 

[Mumbles]

Yep, looks like the nozzle blew out on the first one. I'd suggest ramming/pressing harder. This may involve two things. First thing you may need is a reinforcing sleeve. 1lb rockets are a bit big to be trying to press without a sleeve. Secondly, you may want to invest in some good tubes. This may help solve the crumpling problem, which can become an issue. You don't mention if you're ramming or pressing, but I'd suggest pressing with something of this size.

[Aquarius]

What kind of nozzle/endcap mix are you using? Bentonite, kitty litter etc.

I have had the same problems: My rockets works well, rammed with a sleeve, hand rolled tubes, and when cutting down on the endcap, they blow... I wonder when I will learn, I made the same mistake twise, trying to fix things that are not broken....

[WarezWally]

I used kittly litter which is pretty much pure bentonite, I didn't bother grinding it up so I just used the small pieces.

 

http://www.ihaveadotcom.com/cart/index.php...products_id=256

 

Those are the tubes im using

[Mumbles]

I like Phil, and certainly don't want to take any business away from him. However, those tubes are not the best for rocketry. Spiral wound is by far weaker than convolute. After you use them up, you may want to look into these. They certainly have their uses however.

 

http://www.hobbyhorse.com/pyro_tubes.shtml

 

They are comparably priced, and leaps and bounds higher quality. $32 vs $30 for the same quantity of tubes.

[WarezWally]

Shipping is a killer though, they ship via FedEx.

[Mumbles]

Jim is very reasonable. Give him an e-mail, and I'm sure he will accomodate you. If not, send me a private message, and I can work something out for you.

[WarezWally]

Thanks for the offer, im not ready to rule out my tubes just yet

[Tweetybird88]

Shipping is a killer though, they ship via FedEx.

I don't think so. I found this at the top of their page:

 

Note: disregard the computer calculated shipping. You will be charged actual UPS shipping to your zip code.

[WarezWally]

*im not in the US*

 

And UPS is even worse

[Tweetybird88]

oh, ok. I'm not a big fan of the united parcel smashers myself. Give me the good ole' usps any day. I have never had a single problem with them.

[qwezxc12]

When I realized I hadn't made a rocket in a while, I knocked together a 3lb. endburner from some Poplar BP I had laying around. I spiked it with +5% 5μm Al to heat it up some...too much, I guess. I made a Slow-mo of the CATO...

 

3lb endburner CATO

 

The 15g salute header went sailing off into the woods and went off ~3 seconds later, so I guess the passfire worked o.k.

[hst45]

I spiked it with +5% 5?m Al to heat it up some...too much, I guess.

"You think you used enough dynamite there Butch?", (Butch Cassidy and the Sundance Kid, Robert Redford and Paul Newman)

 

Thanks for the slow-mo video. I love the way the camera starts to move upward to watch the brilliant assent of the rocket, and then the action shifts dramatically downward. I know the feeling....I've been working on stingers lately and I have the fuel/nozzle ratio dialed in to send the little guys into orbit. I was bragging to a buddy about them, so I made a few at his house and they went great. Unfortunatly....as I NOW know... this particular combination won't lift shit, so when I tried a rather stout whistle mix header the little bugger went up about half way, nosed over, and headed towards the driveway, blowing about 20 feet above my pickup. No harm done, and a good laugh, at my expense, was had by all.

 

Your shells look great, by the way (see ariel shell thread). Sorry that the 209's didn't pop. Great breaks.

[qwezxc12]

I was working on converting the remainder of the shell videos from last weekend, and I thought a slow-motion view of the mortar launches would be cool...so here's a quick video of 3, 4, 6, and 8in mortar launches slowed down to 15% speed. You can see my stand-of distance increasing with each subsequent jump in mortar size...self preservation kicking in.

 

For reference, the trees behind the mortar rack are 16-18 ft. tall, I would guess...those 6 and 8in throw a bit of flame

Video

 

Sorry you couldn't make it hst...I guess I'll just have to bring some out to NH next time I'm out that way...maybe by then, I'll have the 8in'ers dialed in a little better.

[h&k machineguns]

can't remember if I posted this before.

 

I was cleaning out the garage and I found an old thick paper tube I had something shipped to me in. I didn't want to toss it so I decided to make a rocket body from it. I grabbed a few other cheap and easy things from the house and within 10 minutes I had this rocket. Of course the motor took me about 8 minutes to build and had hardly any delay. If I knew it was going to fly like it did I would have added a inch or 2 of comp above the core.

This was a 76/23/1-3 AND 64/32/1-3 Fuel motor .

 

Anyway things you do when your bored.

 

http://pyrobin.com/files/.75%20id%20motor%...%20body%201.wmv

[cplmac]

I got this error HK

 

 

Not Found

 

The requested URL /files/.75 was not found on this server.

[rocket]

I got this error HK

 

 

Not Found

 

The requested URL /files/.75 was not found on this server.

 

You need to copy the hole link into your address bar.

 

"http://pyrobin.com/files/.75 id motor with body 1.wmv"

[h&k machineguns]

Ya I don't know why it divided it like that after pasting it .

[Mumbles]

I fixed the link.

[cplmac]

Nicely done as usual HK, not bad for ten minutes.

[h&k machineguns]

Thanks,

as soon as I find a 15-20' tube I am going to try it again. I think I can get at least 200 feet out of it, but man that thing will be super long. Probably have to stand on top of a truck cab to mount it on the long rod .

[psyco_1322]

Here a pic of the rocket I made and the convention, as you can hear in the video everyone was wanting to see teh thing go, it failed to work right. Now there is a 24oz bottle of trimethyl borate out in that field somewhere. For referance im bout 6'2" or so and it was a 3lb. rocket.

 

http://www.apcforum.net/files/PGI_07_a018.jpg - pic

 

http://www.apcforum.net/files/3lb-nozzleless-greenghost.wmv - Video

 

http://www.apcforum.net/files/PGI_07_a019asdf.JPG - The circled one are some that we made up. You can see one with a small 8oz acetone header that worked just fine.

[Stinger]

Hi all

 

I made my first succesfull stinger yesterday and I was

quite surprised that it worked so good

 

Here are a few dimensions of the casing and noozle:

 

16mm ID tube, homemade

5cm long

3mm thick walls

The venthole had 3mm ID, coated with sodiumsilicate

Vertical noozle had 4mm ID.

The core was 2,5cm long.

 

The fuel I used was made from a slowburning blackpowder.

I grinded it with a mortar&pestle.

 

Here is a pre-firing picture:

http://img95.imageshack.us/img95/781/s8001582wx9.th.jpg

 

And here is the video:

 

http://www.youtube.com/profile?user=BackjardPyrotechnics

 

The take-off wasn`t very powerfull, but it could be better due to the slow blackpowder I used.

Merry christmas to all,

 

Stinger