Screaming Dragons (whistling to report inserts)

[Livingston]

So I rigged up a 1/2 OD rod about long enough to fit in wood and stick out a inch so I can fit a 1/2 tube to pres whistle fuel. My rig is proper but I'm get a weak whistling noise. I'm wondering if my fuel is to hot. Any tips advice and pointers much appreciated. Thanks

[Xtreme Pyro]

A little more info would help..

 

How much pressure are you putting on the comp?

What type of fuel are you using? Using a catalyst?

 

I press mine to about 750 on the gauge with 1/2 whistle insert tooling, with SALI whistle using red iron oxide as the catalyst.

[Livingston]

I'm using my 1 Ton arbor Press with 72 Perc 28 Sally 1 red iron. I've press dozens of 1/2 by 3" K Benz whistle rockets with my press no problems

 

How deep is your jig resece into the tube and how big is the tubes?

[Col]

I use about 4000psi on 1/2" serpent inserts. Tubes are 60mm long, 15mm space for report comp/end cap, 5mm clay bulkhead with a hole in the middle, 20mm of na benz, oxy catalysed, whistle fuel grain and 20mm of empty tube. No titanium in this one, report was just a little loose whistle

 

https://youtu.be/shXteXYc8p0

 

Edited November 8, 2015 by Col

[dynomike1]

I found this video while i was trying to figure out how to make serpents. Now it even gets harder because i really don't know much about rocket type things. The serpents start at 20min.

http://www.youtube.com/watch?v=5Q837iouH8Y

[Maserface]

Dyno, at 20min it looks like hummers to me, three hummer shells and then a serpent to report shell.

[Col]

some whistling serpents in the 2nd mine, the ones in DM`s were a bit short lived

[dynomike1]

That's what I would like to learn how to do.

[Col]

Its dead easy to make them, just a tube with Ti spiked whistle fuel pressed into it. I put the empty tube on a 15mm tall x 1/2" stud and press a thin bentonite clay bulkhead with a hole in it first, (see 1st pic above, i used fe oxide whistle in that one, look for the pink dot in the middle) then the whistle and cap that off with a thin bp layer (see 2nd pic above). As a shell insert you just nose the open end, add a few pieces of blackmatch to pass fire to the bp layer and close it with a clove hitch.

For a mine you could just chuck them in The report comp goes into the 15mm cavity end, add some crumpled tissue to create a barrier and seal it up with hot glue or epoxy.

Edited November 10, 2015 by Col

[dynomike1]

So the pink dot is the report? The open end you do it like a spoolet. 70/30 Potassium Perchlorate, Sodium Benzoate. Will this work? Or 66/34/10S? Actually it was 20:16 i think.

Edited November 10, 2015 by dynomike1

[Col]

The pink dot is the bottom end of the whistle grain that will ignite the report comp that goes in that end of the tube before its sealed up. You only need a mm or so of bp covering the whistle grain at the other (open) end to help ensure ignition. I use standard 76/23/1/2.5 (perc, na benz, cu oxy or red fe ox, mineral oil) whistle fuel.

 

Here`s the tooling i use to make the bulkhead, its just a chunk of 1/2" od x 1/4" id aluminium tube and a chunk of 1/4" brass rod, the tapered end was done on the drill press. I use a solid 1/2" stainless steel rod to press the whistle.

 

Edited November 11, 2015 by Col

[dynomike1]

I got it. Thanks Col. All i have to do now is read up on whistle.

[Col]

No worries, btw you dont have to use the bulkhead if you dont want to, you can just dump the report comp on top of the pressed whistie and cap it off. I like the added confinement and short delay it provides.

Whistle fuel is simple enough, dump everything into a ziploc bag, add acetone and squidge until its a uniform colour. Allow it to dry to a soft putty consistancy and then push it through a screen to create worms

 

[dynomike1]

I got 1 more question. Col i see your tubes are 2.36", all i have is 3" tubes. Do you think they will work with 3" or do i need to cut them?

[Col]

you can use any tube length within reason as long as it will physically fit in the shell or mine etc. Take up the slack with a longer report cavity and/or more empty tube above the whistle. Its a good idea to ground test them so you know how long the whistle grain will burn for. The 60mm tubes use 5g of whistle, 200 serpents per kg

[dynomike1]

That will be about a 1.5" of report i think i will cut the tubes, or order some because mine are 9/16, 1/2" are hard to come by. I had to order some Cuo anyway.

[Col]

I roll a custom od tube just for serpents, hummers and farfalle inserts thanks to a support tube with an odd id. You could use standard 1/2" id x 5" long rocket tubes cut in half which might work out cheaper/easier.

[dynomike1]

I'll try these 9/16" tubes first till get some 1/2". I also use these tubes for Farfalle and Go getters. If they work i won't have to buy anymore for awhile. This formula is supposed to have good power. I hope i have better luck with this than i have had with go getters. I haven't got one off the ground yet.

Pot Per 64

Pot Ben 32

Cop Oxy 2

Pet Jelly 5

[Col]

2 parts of cu oxy seems excessive, even 0.5 is enough but i always use 1 part. The whistle will need to be reasonably quick to provide sufficient thrust. Here`s an idea of the 76,23,1,2.5 performance, not the quickest but quick enough.

https://youtu.be/j6Q2MyDy6Wk

[dynomike1]

I'll try it. The one i had came from firesmith.

[dynomike1]

How long does it take this comp to dry? From yesterday evening till now i can't tell any difference in it.

Here is what i did

5lb. batch

Perchlorate 76=3.8oz.

P Benzoate 23= 1.15

C oxychloride 1= 0.5

Vaseline 2.5= 1.25

Lacquer thinner= 6oz.

[Col]

Mine doesnt take more than a few hours but i use acetone and mineral oil. After the comp is uniformly mixed/squidged in the ziplock i leave the bag open for the acetone to evaporate. Doesnt take very long for it to reach the soft putty stage for screening into worms. I let the worms sit on a sheet of kraft until the smell of acetone has gone, typically an hour or so. You could dry it over a pan of hot water (no flames) if you`re in a hurry but i`ve never bothered.

3.8oz (107.7g) of perc doesnt seem right for a 5lb (2.268kg) batch, it should be closer to 60.77oz.

 

Perchlorate 76=3.8oz. 107.7g

P Benzoate 23= 1.15 32.6g

C oxychloride 1= 0.5 14.17g, this definitely isnt right

 

Looks like a 5 ounce batch

perc 3.8oz (107.7g)

Benz 1.15oz (32.6g)

Cu oxy 0.05oz (1.417g)

*mineral oil 0.125oz (3.54g)

acetone as required.

Edited November 19, 2015 by Col

[dynomike1]

Sorry Col after racking my brain i noticed that is a 5oz. batch not 5lb. That was the first batch i made, If i messed up i wouldn't lose much. Do i have to change anything to change to mineral and acetone?

Edited November 19, 2015 by dynomike1

[Col]

Wotking in ounces gives me a headache, i prefer to use metric. Use the same weight for mineral oil as vaseline, you only need enough acetone to wet the comp out so its workable. If you overdo it, open the bag and let the excess evaporate.

[dynomike1]

I guess i am the same way about metric, it doesn't make since to me. I think the next batch will come out better now that i have the first one out of the way. I really appreciate your help on this, maybe i will be able to help you someday.