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Nozzle less rockets


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Posted (edited)

Here are my two from two weeks ago, both 3#, the first is Universal Hybrid and the second is BP tooling the same length but a lot thinner.

 

VIDEO

 

I tried oil in one, just 1% and it wouldn't lift off. It pissed off the rack owner too since it melted his tube ;)

Edited by dagabu
Posted
How much oil are you adding?
Posted

I added 2% oil which resulted in an unusable rocket dagabu added only 1% oil still the same result it seems that having a good grain formation come's at a hefty price.

 

I have decided to no longer use oil from here on in. But oil would make a great burn rate depressant the best i have ever seen!!!

  • 1 month later...
Posted

I just can't seem to get my nozzelless rockets to work

can anyone please help

Posted

How much oil are you adding?

 

Oh hell Mum, sorry, I missed that one. 1% mineral oil with a 10:1 white gas carrier.

 

Nozzleless rockets in my experience are best done with modified spindles. I have used standard BP tooling too but they dont lift much and I like heavy payloads! 300g on a 1# and 600g on a 3#. While I really like my Universal Hybrid set for nozzled rockets, I found that the divergence was a waste and so I turned a slightly bent UH spindle down and removed the divergence.

 

The taper is still 1.5° and the base is .5", it works very well with super hot BP!

 

Without knowing a thing about your process, I will make a wager that you are using less them desirable BP and pounding them and not pressing them.

 

Give us some more info please.

Posted
I use BP made with Pawlownia (very hot) with 20% hardwood charcoal added and 1% wax, they really zip!!
  • 3 months later...
Posted

How do you get the wax into the bp? Heat it in a solvent ??? What about moistening the bp with a touch of water to help compact it then let it dry a couple days??

 

Steve

 

 

Posted
There were some people on passfire a few years ago who were experimenting with pressing rockets damp for a while. Apparently it allowed for higher pressures and better compaction, and quicker burning fuel. It might be something to try out to see if it could be useful.
Posted

Well

Ill find out tonight :rolleyes: I rammed them a couple days ago.

Not sure if i want faster burning fuel or not?? I catoed a couple with nozzles the other night and they were over the top loud. Thats why im going nozzleless right now.

 

Steve

Posted

Well

Ill find out tonight :rolleyes: I rammed them a couple days ago.

Not sure if i want faster burning fuel or not?? I catoed a couple with nozzles the other night and they were over the top loud. Thats why im going nozzleless right now.

 

Steve

 

Sounds nice and hot, please post some video. ^_^

  • 3 years later...
Posted

I think...

 

The oil allows the BP to pack better in the tube, also it keeps things less messy.

 

And the point of a nozzless motor is to greatly decrease the chance of a CATO.

 

Mabye he thinks 3# is what it would take to lift a 2" salute to the desired hight.

 

I wanted to resurrect a five year old thread so that we can start a somewhat new conversation about the trend of using skinny spindles again. With the testing that Maserface did last week showing a vast improvement in impulse by using a skinny spindle (5.07 v.s. 4.36), the door is open for discussion about DJ's nozzleless designs, Maserface surprising (to me at least) improvements and the whole skinny-spindle subject.

 

Perhaps Maserface will post those graphs (I may have missed them here) here for us to look at and ponder.

 

I guess I will open with a question, do you see yourself going to skinny-spindles in the near future? Why or why not?

Posted

Already went there with certain motors. Why? I like rockets - all of them.

 

20150122_180002.jpg

Posted

Very nice Nate!

Posted

Sorry for the lack of a better reason. Despite owning a test stand, I have not done any scientific studies comparing the relatively skinny taper pins to the much fatter universal design. I do enjoy making and flying various types of rockets. They all have different effects and challenges dialing them in. That is what I enjoy the most.

Posted (edited)

I have one custom set with an extra long and skinny spindle (3lb) but experienced too many catos, unless using seymour's ap formulas. And then, the burn time is actually reduced (shorter bulkhead), which I also don't prefer.

 

Lots more experimenting is due though.

 

At this point in my life, I enjoy sending rockets miles away more than I do lifting large weights.

Edited by ddewees
Posted

Well It sounds like you should shift gears and make "partial" end burners ( way less spindle) .

Posted (edited)
You may be right. So far, I've had better luck with nozzled cored rockets for the longest distances. The end burners don't travel as fast, and usually burn through the side if made too long. Edited by ddewees
Posted

Already went there with certain motors. Why? I like rockets - all of them.

 

20150122_180002.jpg

 

that is a hellofa spindle!!

Posted

 

that is a hellofa spindle!!

 

That set uses taper pins as spindles. Pictured is a 6" long spindle for 1" rockets, I have 1"-6" pins which are interchangeable. I have only used the shorter ones so far with whistle, but have a longer rammer on the way to use with slower fuels. More to come this Spring.

Posted

Was that a set from Steve? I have a set too but with the shorter pins, all for whistle.

Posted (edited)
Yes sir, it is a great set. He says they are for whistle, I have been using it for more. I made a purple and gold gerb with it yesterday. Edited by nater
Posted

I dont know where got the tapered pins from but when I look for the longer ones, I get disappointed and frustrated. Great set for dialing in whistle though.

Posted

One question, why do you want to use these verry skinny spindles.

What is the advantage of such a skinny spindle compared to a fat one like on bens nozzleless rocket set?

Posted
The skinny spindle lets you press more fuel in there for a little longer burn time.
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