End Burner

[Flaky234]

Hi,

 

I want to learn something about end burning rockets!

 

I know that you have to use the fastest meal as possible, but can Willow be replaced with grill charcoal or must it be light charcoal?

And can Titanium bp used all the way up the rocket?

How is the Titanium added to the bp? Just mixed in the meal and then granualted or is it shaked in after granulation?

Is it ok to add 5% water to the fuel and then push this through a screen to keep dust down?

And are the granulates soft enough to compact good when using water (bp without dextrine)?

 

So my final question is how much payload can a "good" 15mm id and 100mm long endburner can carry? 50g?

 

Thanks

[pyroshell]

Using grill charcoal will result in a slow burn and little thrust.

For making rockets there is not granulation step.

I usually add Ti or Fero-Ti to my rocket motors while ramming.

Once you are past your mandrel it is safe to add Ti...but you want a few layers of bp just for safety reasons.

If Ti gets in between you mandrel and you rammer you can have friction issues causing ignition.

As far as how much it can lift all depends on what comp you are using to fuel it how you ram it (it effects the density of the fuel), but it should be able to very easily carry 50 grams

Typically I don't use dextrin. I just don't see any reason to besides to slow down the burns, but that’s what 80 mesh charcoal is for. Since you use no water there is no solvent to activate the dextrin so it does not help.

[PyroCube]

I tried my luck un endburners a while ago, it was quite disappointing.

I never had any good results with lifting payloads, my goal was 50g (2" ballshell)

with a 15mm motor, just like you.

When I went for smaller nozzle diameter (1/4-1/5 of Rocket ID) I had always a nozzle failure,

it just blew out. My ramming pressure is probably too low to get a proper nozzle.

But don`t make your fuel grain too long, I think 2" BP fuel would be enough, and make shure you

use the fastest BP you have, ballmill is required.

 

Greets

[Oinikis]

what nozzle mix you used? plain bentonite from citty litter always failed me, but coffemilled, with 8% paraffin melted into works super well.

[PyroCube]

Coffemilled citty litter, without paraffin.

Ist it more resistant with paraffin? Sounds illogical to me...

 

Greets

[Flaky234]

Hi PyroCube,

 

I saw your videos and I think you should buy a Tooling made for the red tubes!

 

I have a ballmill^^

 

So I shake the Ti into the dried granulates of bp?

 

Thanks

[PyroCube]

Homemade tooling always worked out well for me.

If you use Ti in your fuel, always make shure that you

ram it above the spindle of your tooling.

 

When I used Ti I found that the thrust of the motor is decreased by using Ti.

For the start, it`s enough to use 4% of fuel weight, it still gives a nice effect.

 

Greets

[pyrokid]

For my core burners I do granulate the fuel to reduce dust. Just water, no binder.

[Flaky234]

Hi,

 

So I add the ti to the bp and granulate it to reduce the dust?

 

Thanks

 

btw. nice youtube channel^^

Edited March 18, 2013 by Flaky234

[PyroCube]

Yes, that would work out pretty well I think.

If you have rubbing alcohol available, I would granulate with

that, so you have less drying time and ramming a compact fuel grain

is easier since the granules are softer.

 

 

Greets

[Flaky234]

Ok,

 

Danke^^