10 replies to this topic

[PyroNitrate]

I found theys on a website, I thought it would be useful im not sure how many of you use the two but information is information

How to make Dextrin
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Dextrin is used as a binder in some compositions, such as start mix. To make dextrin you will need the following:

Wheat flour
Tin-foil
Oven
A Backing tray

Simply turn the oven on a medium-low gas for a few minutes. Then get the tin-foil and spread it over the backing tray so its all flat. Now simply pour a thin layer (1cm) over all of the tin-foil. Put this in the oven for about 2 hours. I only put mine in for 1 hour but you are supposed to put it in for 2 hours. Make sure you have it on a very low gas or it will burn. Kepp checking every 30 minutes to see if its ready to be taken out. You will no when its ready to be taken out because its will be a pale yellow in colour.

Dextrin Properties taken from the BPS chemical database

Chemical name Dextrin
Chemical formula (C6H10O5)n
Uses Fuel
Binder

Hazards
Description A light yellow powder often used as a binder and fuel in firework manufacture. It has good adhesive properties and it is also easy to produce.

Soluble in water.



How to make Charcoal
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First of all to make charcoal you will need a tin similar such as a cookie tin. You will have to drill 2 holes in the lid and put some chunks of wood from a wilow tree inside it. Place the lid back on the tin and place the whole thing on a small fire for about 3 hours(depending on the size of the fire). Once you stop seeing smoke comeing out of the 2 holes that is when to take it of the fire and place it some where to cool with the lid on. Leave it for half an hour and then take the lid of and gather the charcoal together. If you do not use wood from a wilow tree the charcoal will not be as good as it could be.

Chemical Properties from BPS database

Charcoal
Chemical formula C
Uses Fuel

Hazards
Description Very widely used fuel in compositions. Charcoal is an impure form of carbon made by removing the volatile substances from wood by heating it in an oxygen negative atmosphere.

There are many types of charcoal, and the choice is essential to gain the highest performance for a particular composition. However manufacturers are often limited to what is available.


Hope this helps

[Stuart]

Yep, Pyromasters website. He's a member on this forum but hasnt been on in ages.

[BigG]

I tend to disagree with the quality of the procedures. First, you can?t really say that Dextrin is ready by it changing colour, you need to test if it?s ready. Second, the wording ? if you don?t use willow then the charcoal would not be as good as it could be? is a very unclear statement. Willow is good for fast BP, but is definitely not the best for either sparks or consistency. Also, ?cooking? times vary greatly depend of the size of the logs, the fire, the set-up and so on. The smoke is a good indicator ? but commercial producers will cover the smoke holes on the vassal (in this case the tin) when it is taken off the fire to prevent oxygen from coming in.

BigG

[Richard H]

For example you can chemically test your dextrin to test for the presence of starch. A brown colour change from purple is what you are after.

Although the colour does give a loose indication that the dextrin is nearly ready.

[Matt]

I think I know why pyromasters fuse doesnt work, that aint' no dextrin! I was always under the impression that corn starch was used, not wheat flour. They are two completely different things if im not mistaken.

-Matt

[mrpyromx]

I was always under the impression that corn starch was used, not wheat flour. They are two completely different things if im not mistaken.

-Matt

Im with you matt. I assumed the same thing. Hmmm, who knows the right answer for dextrin? Or can eather be used to make dextrin?

[BigG]

Hey , I completely missed that? Yes, you are right, Dextrin is traditionally from corn starch (in many countries, including the UK, this is called corn flour. In the USA, corn flour is something completely different?)

Just to clarify Richard?s post ? iodine is sensitive to starch, and iodine solutions will change to deep brown/purple/black when come to contact with even traces of starch. As such, one can buy tincture of iodine (available at your local pharmacy), and mix about five drops with 50ml of water (can be tap water) ? which will give you a clear light-blue/purple solution. Place a small sample of your dextrin into the glass (just the tip of a spoon) and mix by shaking the glass. If your dextrin is ready, no colour change will be observed. If your Dextrin not ready, the colour will change dramatically.

BigG

Edited by BigG, 15 August 2003 - 04:53 AM.

[Pyromaster2003]

ahha, not wheat floor then?il go and look for some corn starch tomorow then. in safeways?:)things have changed sooo much round here over the last 2 weeks, guna take me a while to get used to this new setup, looking very good though.

[smpip]

For example you can chemically test your dextrin to test for the presence of starch. A brown colour change from purple is what you are after.

Although the colour does give a loose indication that the dextrin is nearly ready.

Could the Honcho and Mr G colaborate and agree on this topic because there seems to be an amount of conflicting info, only a tad though

Oh yeah, welcome back Chris, has it been two weeks already

Edited by smpip, 17 August 2003 - 12:10 AM.

[Pyromaster2003]

yer thanks, affraid it has, could of stayed another 2 though

this damb new forum setup is driving me nuts,but il get used to it...eventualy

[Richard H]

For example you can chemically test your dextrin to test for the presence of starch. A brown colour change from purple is what you are after.

Although the colour does give a loose indication that the dextrin is nearly ready.

Could the Honcho and Mr G colaborate and agree on this topic because there seems to be an amount of conflicting info, only a tad though

Oh yeah, welcome back Chris, has it been two weeks already

BigG is correct, my mistake. Your trying to remove the starch by heating it.