Rocket Fuel consolidation

[Paradise]

I was just wondering if for example while ramming black powder core burners if one word to use light and gentle blows like if you were chiseling Stone would the fuel ever become completely consolidated or is a hard blow or the use of a press the only way to achieve this? I realize this may not be practical but I'm not wondering about that I'm just trying to understand more of the physics behind it I think that's the right word anyways. 😊

[NeighborJ]

If you give hard wacks, the fuel against the drift will compress hard, never allowing the fuel underneath to consolidate properly. If you give the right blows the increment will compress fairly evenly,only slightly more dense at the head of the drift. The trick here is how hard is good and how heavy is too heavy? This is the reason many use a press, it is far more consistent and will be much easier to diagnose if you have a motor failure. Once the press is set, it becomes routine to make consistent motors, where as when hammering out the motors it is likely you may never reach the performance and predictability of the press. You can have consistent motors by ramming but it is hard to judge a hammer blow. Edited September 18, 2016 by NeighborJ

[dagabu]

J touched on most of the issues but please allow me to add the idea of including a wall friction reducer as well. if you wax your tubes or even dust the tube walls with graphite, you can significantly reduce your losses to pressing out rather than down. J said it the best way I know how, use the "right" blows for the comp and tube.

 

That said, you will find wide variation across manufacturers using hammers of different sizes, hardness and materials pounding with baby taps up to full body blows!

 

Make sure to use small increments when hand ramming, especially on larger rockets such as 1# and up, you may end up with all powder under the hard cap of rammed powder if you don't.

 

The real reason that I use a hydraulic press is the ability to apply 'dwell time' to the comp. This allows the comp to settle and make a harder increment. I have witnessed this many times when removing somebody's stuck rammer from a spindle. I cut the tube off and open it, some of the comp comes out as powder, not compressed at all.