Chuffer and Oiled BP

[usapyro]

I have been reading around and it seems like there is a BP composition out there that is higher power just by the addition of mineral oil? If anyone here uses a comp like this, how much higher power is it?

 

I have just discovered that sally whistle mix still wet with naptha chuffs quite nicely.

 

I'm thinking a BP with a ratio of 75/13/8/4(mineral oil) sounds about right, and BP +6% mineral oil or so you get a good chuffer rocket?

[SjeefOne]

Nozzleless BP motors are made with mineral oil, but I wouldn't say they chuff.

I've made nozzleless motors with varying ammounts of M.O and found that 3% is too much (for my charcoal anyhow),

the fuel gets too liquid under pressure. This makes it ooze around in between the rammer and into the hole making it hard to get it out of the tube.

 

I think 4 or even 6% oil would be allmost impossible to press, but you could allways try

[usapyro]

Hand rammed BP I think I can get it to work just fine by not pounding so hard.

 

Ohhh... So with nozzle-less the mineral oil helps prevent chunks of powder being blown off the grain...

[Short5]

Hand rammed BP I think I can get it to work just fine by not pounding so hard.

 

Ohhh... So with nozzle-less the mineral oil helps prevent chunks of powder being blown off the grain...

I believe it also slows the burn rate, not speeds it up, allowing fast BP to be used in the nozzleless rockets. Mix +2% of the weight of your BP worth of mineral oil in a shotglass(1/4 cup) of lacquer thinner. Mix it with your BP and granulate it through a 20 mesh screen. The thinner will evaporate quickly. http://www.skylighter.com/fireworks/how-to-make/nozzleless-speed-rockets.asp

[dan999ification]

it is one of many fuel retarders, slows it down, dag was trying to get a twenty second burn from a mineral oil retarded endburner.

you probably could get more power from it if you forced it to burn at once but it defeats the object of slowing the fuel in the first place

 

 

dan.

[SjeefOne]

Mix +2% of the weight of your BP worth of mineral oil in a shotglass(1/4 cup) of lacquer thinner. Mix it with your BP and granulate it through a 20 mesh screen. The thinner will evaporate quickly. http://www.skylighte...eed-rockets.asp

I've found there's even no need for the lacquer thinner. Just mill your bp, add 2% M.O in the jar and mill for another 10 minutes. However if you use too much oil it will coat your media with nice black goo.

[usapyro]

Nice... Thanks SjeefOne. I was thinking about doing that but unsure if I would end up with a sticky mess.

[Blackthumb]

BP 8/fine cedar sawdust 1...slower fuel..steady take off and continued burn through end of flight..no mess...no cost. Too easy....

[dagabu]

BP 8/fine cedar sawdust 1...slower fuel..steady take off and continued burn through end of flight..no mess...no cost. Too easy....

 

I love the sparks that it produces but I have to top fuse the rockets to get enough thrust to leave the tube

 

-dag

[Blackthumb]

I have been adding a bit of TI to the mix. Using small rockets...5/8 ID x 3"...also do a 7:1 mix for 3/4 ID x 5"...they throw lots of sparks and really roar with a continued burn....they are both cored...lit midway in the core...

 

Also like the mix for saxons....

[SjeefOne]

Nice... Thanks SjeefOne. I was thinking about doing that but unsure if I would end up with a sticky mess.

Just don't put too much in there or it will deffinately be a sticky mess. With about 2% i get a nice non dusty comp, i suspect it's depending on what charcoal you use though.

When I feel the need to clean the jar then I just put hot water in it and a bit of dishwashing detergent and let'r spin for 15 minutes and everything is clean again.

[RichC]

I'm sure that this is off-topic, but just in passing you've answered the question that I've been grappling with -- water & soap in the drum and then spin for a bit. Thanks for the simple answer.

 

Rich