248 replies to this topic

[portfire]

Looks very nice, those tubes are hand rolled right?

Should make a basic start sizing plate, only takes a few mins to drills holes in plywood

Yup hand rolled.Well i'm off to the "workshop" soon so may do just that marble

dean

[Pyromaster2003]

Nice looking rocket there hope it works for ya.

Made a 1 incher the other night just with a Ti flash report. Was an endburner and reached 500ft in about 3-4 seconds. Im addicted to these rockets, and the best part is they only take 10mins to make. The tube was 5 inch long. Got it on video but my comp is playing up and can't get it from the cam so il let another one off tonight and get it on my phone. Got a couple of pre-fire pics..

http://www.pyrotubes...ocket1inch.html

[marble]

err all i see is a mitre saw?

I'm still waiting for my tooling to come (1lb), looking forward to lifting a few shells.

Made a batch of fuel but im worried its to fast for coreburners, worked well on my 1/2" endburners.



(yes i know, unsafe but the visco decided to fly around when lit)

Edited by marble, 30 September 2007 - 01:40 PM.

[Pretty green flames]

Good luck portfire, hope this one flies Let us know how it works out

[dr thrust]

good luck with the rocket dont give up! keep the faith

Edited by chris m, 30 September 2007 - 03:59 PM.

[Jerronimo]

Already posted this in the tubes topic but I think it's more appropriate here.

Normally I wet my rocketmix with 15% water, rice it and let it dry.
When browsing trough the passfire forum I noticed that some rocket guys use a different way to prepare the propellant.
Vaseline is used to control the burnrate, avoid dust and compact better to produce a tougher very solid propellant grain.
It's very simple realy, I will illustrate the procedure and report my findings.

Begin with a standard 1 pound rocket mix, I use a pretty hot 65/25/10, the charcoal is airfloat pine, and the chemicals are all ballmilled together for 1 hour.
Add 2% vaseline(you can melt it by slowly heating it) now add some laquer thinner to the mix untill you get the same texture as when normally ricing your rocketcomp and rice it as normal.
I suggest drying this outside, as the thinner will evaporate and produce unhealthy fumes.
This propellant obviously dries alot quiker than normal riced bp, when you can't smell the thinner anymore the propellant is ready for use.

I pressed the rockets on my new 12 ton press, with a pressure of 7500 PSI on the rammer, using the 1 pound tubes from Chris and a double PVC sleve to support the tube.
I tested a couple of them today and was impressed, they took of realy fast and flew very nice, powerfull stuff.
Next time I will add a payload and see what weight these rockets can take to a good height.

[dr thrust]

thanks just made/ riced, some today useing you comp but didnt warm up the vaseline just melted it with thinners, bit of a messy job! just waiting for the thinners to go, so i,ll give it a few days to be sure, looking foward to making a 1lb,er with this new rp thanks, just tried a bit and it burned very smoothly

Edited by chris m, 30 September 2007 - 05:40 PM.

[Pyromaster2003]

Is anyone else just seeing a pic of a mitre saw on the link? I see two pics of the rocket.

Got any vids of these core burners you making Jeroen? will be interesting to see what they can lift compared to the end burners i make. Do you cut the 1lb tubes to 7.5"?

[W.P]

Nice looking rocket there hope it works for ya.

Made a 1 incher the other night just with a Ti flash report. Was an endburner and reached 500ft in about 3-4 seconds. Im addicted to these rockets, and the best part is they only take 10mins to make. The tube was 5 inch long. Got it on video but my comp is playing up and can't get it from the cam so il let another one off tonight and get it on my phone. Got a couple of pre-fire pics..

http://www.pyrotubes...ocket1inch.html

1" Rocket with a 3mm nozzle? What type of BP were you using? If I attempted that even with poor greenmix I'd have a nozzle blow out/CATO, guess those tubes really are incredible.

EDIT: Just noticed the 3mm hole was for the passfire

And a recent rocket I made:

Rocket:
-Core burner with a 6mm nozzle
-RPH using willow charcoal
-1/2" diameter tube, about 3" long
-Black match fuse

Payload:
-2" can shell
-Greenmix+25% Al stars (Simple yet highly effective)
-Benzolift burst charge
-Weighed 50g



The rocket and payload worked so well, it's just my poor camera which made it look horrible:

http://video.tinypic...p?v=10xr7rn&s=2

The effect was much better in real life, I hate my camera.

Edited by W.P, 30 September 2007 - 06:56 PM.

[Pyromaster2003]

I can imagine what that would have looked like in person very impressive rocket for a 1/2 incher!

Yea.. i use a 5mm hole with a meal based comp but slowed down with unmilled BP. And here is the vid i said i would make, same problem with camera quality but you get the idea..listen to the roar of this 1" end burner:)



PS off to make some more:) lol

Edited by Pyromaster2003, 30 September 2007 - 07:13 PM.

[W.P]

Yeah, I was shocked that it even managed to lift it. RPH is an incredible propellant for me, I didn't even mill the willow charcoal, KNO3 and sulphur- I simply coffee grinded them individually and screened together. Charcoal Dust has great willow charcoal.

[Jerronimo]

Hey pyromaster nice to hear you're having fun making and testing those 3 pounders, nothing beats a good rocket, keep them flying!!!
Any idea what kind of payload they can lift?
I think I will order some of those 3 pound tubes very soon, waiting for a pricequote on 3 pound core and endburner tooling from greg boyd.

And just launched a couple of 1 pound coreburners with a 3'' round shell payload.
Shells were plastic with tigertail/Ti stars with blue core, bp ricehulls and 6 grams of whistle glued together no extra pasting, weight about 150 grams.
Pushed it a little bit, 6 grams per shell is realy to much they made a massive bang , fragmented most of the stars.
It literally rained star and shell fragments .
Besides that the rockets flew perfect! reaching a very nice height(maybe to high) and leaving a nice charcoal tail, they roared pretty nicely to
Sadly no video, need to get a decent digital video camera to film these babies.

I think I have them dialed in now, made about 6 now and all went up perfect.
with a press and gauge you can press every rocket to the same density making for very consistant results.

Keep us informed how that vaseline rocket propellant works for you Chris m.

Edited by Jerronimo, 30 September 2007 - 08:13 PM.

[Pyromaster2003]

Im sure a 3lb core burner could lift a 6inch shell easy. End burners - not sure but at a guess 4" maybe 5. Il have to get some more scales to do a test on the thrust of these big mothers got over a kilo of initial thrust using the 3/4 inch tubes (possitive i can get more though) so the 1"ers i think it will be more like 1.7-2kg initial thrust.

Theres not much point buying a tool for making an end burning rocket bit of a waste in my eyes all you need is a wooden dowel and a drill..thats what i use and they are perfect.

Sound like some very good rockets you made shame about no vids ya gota love a good home made rocket video. Its fun testing and experimenting rockets but nothing beats it when you have em shooting of like a bullet every time with no cato's or upside down fountains lol.

[dr thrust]

yes it is fun testing rockets! just tested four flavours tonight no headers, all 3/4 inch ,7 inch long with 1/4inch nozzle with 3ft sticks(to short! it was like missile command)

anyway, rocket one was 72,24,4 way to fast just on the edge of cato i,d say, rocket two from this forum 70,20,10+10 airfloat willow, fast with a thick orange tail

rocket three, meal 4, charcoal 1 nice and fast but i might add more charcoal it was over very quickly i like my rockets to ascend slowly you get more of a show for your buck! rocket four 13,7,2 from brocks book perfect!

Edited by chris m, 06 January 2008 - 04:26 PM.

[portfire]

Well what can i say,(loads of foul language)another CATO but,this one was alot more promising.It did lift,got to around 20' then CATO'd (blew endplug out).It looks like the fuel is still to quick(my ballmill kicks ass ) but,only just so, i'll add 20%C in the next one.

No vid.My brother WAS suppose to be filming but messed it up Its a shame really as it was quite impressive.

Some postmortem pic of nozzle&endplug..or the lack of it .



dean

Edited by portfire, 01 October 2007 - 09:53 AM.