196 replies to this topic

[MDH]

Pipipi was your charcoal already airfloat quality?

[pyrotrev]

There was an interesting article posted on the Skylighter website newsletter on April 14th about granulating BP using red gum in alcohol (rather than dextrin or gum arabic with water as is normal practice) and putting it through a coarse sieve. It claims performance comparable with commercial BP even with poorly milled ingredients. Go here: http://www.skylighte...es/articles.asp

[Pyrogeorge]

Pipipi was your charcoal already airfloat quality?

i bought the charcoal from super market and i grinding it until it makes fine powder.

[portfire]

i bought the charcoal from super market and i grinding it until it makes fine powder.

What type of charcoal, I'm guessing 'Lumpwood' ? If you bought BBQ briquets or that 'self-light' charcoal then don't bother. Lumpwood will make acceptable BP. If you can find a source of willow charcoal (or tree's and make your own charcoal) the better.

Also, try varying the amount of greenmix you load in your jar, as over or under loading the jar will effect milling time. I've found that when I mill 100g, I hit a burnrate "wall" after 3hr, I increased milling time to 4hr, and no difference in burnrate, but when I mill in 60g batches I get really fast BP in 1 1/2hr.

Dean

[Pyrogeorge]

yes it is lumpwood charcoal for BBq,but not self light charcoal..
lumpwood is not good to make BP??

[portfire]

yes it is lumpwood charcoal for BBq,but not self light charcoal..
lumpwood is not good to make BP??

Yeah, lumpwood will make acceptable BP for every application, but willow and a couple of other charcoals, will considerably increase the quality and burnrate of your BP..Read the 'making charcoal' thread to find out more on different charcoals used for making top quality BP, but then,there are other factors that play a roll in BP production

The only way forward is to read, (very important) experiment, and find what works best for you and stick with it

Dean

[dr thrust]

i got a big bag of lumpwood last week, god its boring bashing it up! need to invest in a hand mincer me thinks, thanks for the link pyrotrev this red gum/ alcohol riced bp sounds very promising

[MDH]

Hmm. I wonder if Steve Baron is still making paulownia charcoal? His stuff is extremely fast!

It will cost a lot of money to ship two pounds of it, but one gram can launch a 1.75" shell (about 28 grams in this case) quite a distance.

[Pyrogeorge]

My granulated BP from grapevine charcoal..I think that is fast for lift uses.Your opinion?

[MDH]

Yes... it is.

Edited by MDH, 08 June 2008 - 02:42 AM.

[Pyrogeorge]

Is it dangerous to make BP in summer period because of heat weather and high tempreture?Also it is possible to explode in milling jar at the time of milling?

[dr thrust]

how hot does it get there?, never thought of that before because we dont have a summer over here in old blighty

[Pyrogeorge]

Normal days around 35°C and at heatwave days around 42°C

[cooperman435]

Those ambient day temperatures shouldn't effect bp as they are way way below its ignition point, however any energetic compound we deal with will be made easier to ignite by a higher temperature

Milling jars combusting is something everybody should take into account regardless of any other factors anyway.

[knackers]

[quote name='cooperman435' date='Jul 19 2008, 05:53 PM' post='46570']
''it all relates to relativety, for instane, if it takes an aeoroplane 250 knts for take off and you have a head wind of 50 knts, therefore you only need a ground speed of 200 knts for take off, Simliar for bp, you still need combustion temp for ignition, regardless'', a car with all its windows up, in the sun , on a hot summers day, ( 36c ) will have an inside temp of approx, 60-70 c ( very hot ) but still not hot enough to ignite bp, it is said '' quote, '' never assume anything '' end quote, now then, you guys in the uk' can relax a little on temp related ignition, ( when it relates to bp ) we here in australia, ''i can only assume'' our temps are a wee bit warmer than yours, ( we had temps a few months ago at 44 c in my back yard, ( in the shade ) and had no auto ignitions regarding bp, ( or any comps for that matter ) ( our biggest prob was our ball mill motors over heating, btw, nice bike coops, its a great ride on the great ocean road down here on the west coast of vic, you'd love it,

Edited by phill 63, 20 July 2008 - 08:10 AM.