Bentonite Storage - Rocket Nozzles and Humidity Changes

[usapyro]

The humidy shifts around a rediculous amount around here so I was thinking about whether I should climatize my bentonite or keep it perfectly dry. I have decided on keeping it bone dry and storing my rockets in sealed bags. The only problem could be the rocket nozzles expanding and bursting the casing when being left out in higher humidity. Not sure if that could happen or not...

 

I have noticed that used rocket nozzles become brittle and shatter into rings easily when they sit in higher humidity for a while... Or even just fall apart when you go to pick them up. These are used nozzles with the casing taken off.

[nater]

I melt a little parrafin into the clay to help prevent a formed nozzle from absorbing moisture.

 

Just heat the clay up in a low temperature oven. Melt some wax and stir it into the warmed clay. A solvent may be necessary to help mix the wax into the clay. Then granulate the mixture and allow to dry.

 

I use hawthorn bond fireclay with 10% graphite and 10% wax, but the amounts can be experimented with to get yout best results.

[Col]

I use a similar mix, bentonite based (non clumping) cat litter and paraffin wax from tea candles. The cat litter is blitzed in an old food processor and heated with the wax in an old pan on the gas stove. I screen twice and reheat it in the pan between screenings.

Edited November 1, 2012 by Col

[Shadowcat1969]

I was reading about NGorski's experiences with making rockets at home and then travelling to Wyoming and the humidity differences actually dried up his nozels in a couple days so much that they became loose in the tubes. He said that adding the wax (which I do as well) helps immensely with that. I would assume that it will work the other way around as well, if you start out with dry clay that's been well integrated with wax, it should be much better about not absorbing a lot of moisture and bursting tubes, etc. But I don't know that for sure, and I happen to live in very low humidity 99% of the time.

I use canning wax to integrate with my clay, put the clay in a new paint can (never had paint in it) and place about 10% weight of canning parafin in the center of the clay, then in the oven on 250 for about 45 minutes, then stir very well, granulate through a screen and dry/cool, then re-granulate. Works really well for low dust and for helping the clay bind very hard in a low humidity atmosphere.