14 replies to this topic

[barnsley-mark]

I bumped into a guy who is a charcoal geek, he makes retorts etc but eats, breaths and sleeps charcoal.
I mentioned straw charcoal and being a member on here.
I have now received a free sample of just under a kilo - already tried some myself and appears very good - pressed with a bit of water and dextrin ..... Now can't break the stuff up!
Anyway, I told the guy I would send out some samples to other members - 100 (ish) gramme bags to anyone who wants them to try.

[Creepin_pyro]

Sounds interesting, I've only heard of straw being used for cocoa powder. If you want to PM details I'd be interested in a sample, happy to cover postage/packaging.

[Sparky]

I would definitely be interested!

[Barnsley-Bill]

I wouldnt mind trying some too mate.

[Mortartube]

Straw and grass charcoals are reputed to produce a BP that is more sensitive to friction and shock than usual BP. Some caution would be advised until you have established if that is true with your powders.

[PyroSkitz]

would love some too! pm me details / cost of postage if there is still some going :-)

[Pyro.1]

Straw and grass charcoals are reputed to produce a BP that is more sensitive to friction and shock than usual BP. Some caution would be advised until you have established if that is true with your powders.

i produced some pampas grass charcoal a few years back, the bp was very sensitive, the meal would ignite with a hammer blow. i would think straw would be very similar but as i havnt tried it i cant say for sure, so going by the Pampas Grass Charcoal i would agree with Mortartube and be very carefull lads.

Paul.

[Creepin_pyro]

Good points, for those not aware of cocoa powder this is from the PFP:

"Cocoa powders are more sensitive to friction than ordinary black powder. Accidents have resulted from shaking of the composition in a canvas sack."

Never heard the "shaking of the compositoin in a canvas sack" which does sound alarming. Surely this would present issues with milling too?

Mark, do you have any details of the process used? I'm not sure if the sensetivity comes from the level of carbonisation or just using straw itself.

[Arthur Brown]

I think most of the respected authors caution against "cocoa powder" meaning BP made with straw charcoal. extreme sensitivity being the major issue.

[dan100]

is this due to the si that lines the edges of grasses like saw blades, why they cut you aswell.
It wont burn off at charcoal cooking temps.

Dan.
Edit, im willing to bet on it, after some quick searching it seems that some straw and grasses can have as much as 20 percent silica/silicon as dried product, after cooking this will obviously increase.
Who fancys milling bp with 30 plus percent si ? Not me.
Id want to know exactly what straw it is and research the si yields acordingly, and then still not mill it.

Edited by dan100, 06 December 2012 - 12:43 PM.

[Sparky]

The only thing I can find on BP made with grasses has this advice:

"This type of black powder uses the not fully carbonized type of rye straw charcoal. The straw is not left in the "charcoal-drum" until all the gases evaporated. So it has got a lot of volatiles left in it, which is responsible for its sensitiveness."

[dan100]

thats why its called cocoa powder, it is brownish in colour.
Properly cooked charcoal should not be completely black anyway and will be far superior to overcooked.
My retort is an open topped 10 inch drum, the flame does not jet out of the large hole, the second it is below the rim remove and cover, this yields the best charcoal( for me ) but it needs full attention, if a retort with small hole/s was used the gasses would still be jetting out at this time, aswell as being too hot inside.
The maltese make charcoal in open topped barrels from grasses and brush then cover the barrel in plaster when the charcoal is glowing and the flame has stopped, lots of ash.
Cocoa bp is said to be less powerful than ours due to its specific uses.
Temparature controlled cooking of reactive charcoals will give a better product. And be more sensitive than overcooked charcoal, my brown charcoal will take fire quicker than black charcoal from the same wood the same goes for bp made with it.
Im quite interested to see how this turns out, be safe.

Dan.
See edit in last post.

Edited by dan100, 06 December 2012 - 12:59 PM.

[Sparky]

I presume most charcoal we purchase is fully cooked? It sounds like leaving it brown would have all sorts of issues even with other sources?

[dan100]

i never bought any, but it would most likely be fully cooked yes, not that brown just a tint and when milled it is black the proof is on apc oldguy designed and built a retort for controlling temps, the result was brown (ish) charcoal, plenty of pics i just couldn't catch the colour on my camera.

Dan.

[barnsley-mark]

Barnsley-Bill and pyroskitz, pm your address and I will send some out.
Sorry for delay in getting back on this - been a mental week.
I've tried hitting it, grinding, and even static discharge - no signs of sensitivity.
Definitely some interesting points raised.