12 replies to this topic

[pritch]

Ok. I know there is other topics on this but there is not anything specific for my problem. I have created meal a few times in my mill now and never had any problems.

I have been milling this latet 60 g batch which is my normal 75:15:10 mix for much longer than usual now. I normally only mill 50g at a time. The results are not good. It seems slower burning and leaves yellow residue.

A big photo of a clump of my meal can be found here:
http://www.thehigh-l.../dodgy meal.jpg

Thats approx 400 kb

A smaller version can be found here:
http://www.thehigh-l... meal small.jpg
This is approx 100 kb.

I think the colour might be wrong and may tell some experienced guys what the problem is. Im hoping the extra 10 grams has made it soft and cussiony in there, so the milling is not as effective. I think if you see the photos you may think I have messed up the mix.

Thanks very much.

Pritch


[EDIT]
I forgot to say that the pearls closest to the camera are the latest experiment. The pearls on the far side were from a few hours earlier so it is improving.

Edited by pritch, 04 June 2004 - 02:53 PM.

[Creepin_pyro]

The colour of your meal seems to be a pale brown. I really don't understand this, but I remember seeing someone elses pale brown meal before. What kind of charcoal are you using? - I thought adding the right amount of charcoal usually makes the mix almost black, then once it becomes better incooperated, the meal should have a lighter, more grey apperrance, but I can't see it turning that colour. What colour is the mixture when you put it in the mill?
I've only ever had the pearling problem with my first batches of poor "meal" - That's all sorted out now, and I use airfloat charcoal, and lab grade Kn03 and Sulphur. Not much help, I know .... hopefully someone else will shed a bit more light.

[pritch]

Im using bbq charcoal. It has worked fine every other attempt. Im thinking there is a chance that there was just too much powder for the balls to mush, so I have removed about 10 grams of powder and put it aside for now. I couldn't tell you what colour it was on entering because I added the charcoal after the green meal. The charcoal is dark black though. The only other thing I can think of is that the charcoal could have possibly been damp so there was less than it actually weighed. Im just hoping someone can look at the pictures and confirm something.

[BigG]

Pirch - sorry to disappoint you - but the likelihood of someone telling you what went wrong from this picture is not probable. Try opting for a better charcoal and record your procedure in a log book so it can be repeated in the future if you get things right.

[willd]

I dont know why its that colour. The problem with burning is probably you either made a mistake in measuring, or your mill cant cope with the extra 10g, but i wouldnt have thought 10g would have made much of a difference.

[pritch]

Ok thanks guys. The thing is bigG, I have done everything exactly the same as before. The only difference is I made an extra 10 grams. So basically it has to be that 10 grams or I have made a mistake while measuring which I don't think I did. I just hoped somebody would look at the yellow residue and light grey meal and would have reemmbered having the same problem. It was a long shot. Thanks anyway guys.

[zanes]

I would say that the problem is something to do with clay, either contamination from previous mills or in the charcoal. You're not using briquettes, are you?

[pritch]

To be honest I dont know what the charcoal is. It was in a plastic bag. Thats not the problem though cause it has been fine every other time. I have read on thatrocket dudes site, that white pearls means too much oxidiser. Ive added a tea spoon full of charcoal and it is definetly better now. I think it's now under control. Im putting it down to, too little charcoal due to moisture weighing in extra so I used less charc.

[Nate]

You meantioned meal turning brownish before, we just made some meal today it came out a brownish color, could anyone perhaps tell me what caused this, what it can do and how to remedy it?

Edited by Nate, 17 June 2004 - 11:32 AM.

[Pyromaster2003]

What milling jar do you use? If its a plastic orange one then it could be your milling jar. I put some KNO3 in my mill a while ago and its come of slightly tinted orange, was only milling for half an hour. Prob your milling jar wearing down...

[Phoenix]

It is quite likely to be your charcoal too. If you break a piece, is it black and shiny all through, or is it a similar brown colour? This would indicate that it is not fully carbonised, and needs cooking longer.

What really matters is whether or not it burns OK. Does it? If it does, it probably isn't a major issue.

Edited by Phoenix, 17 June 2004 - 01:49 PM.

[bobconan]

The milling jar is rubber. As for the charcoal its commercial air float.

[pritch]

My color and clumping problem was definetly my charcoal. I am now using air float willow and it does not clump into hard balls, even after 12 hour milling. It is also black. The meal straight out of the jar is faster than my pulverone using the old charcoal. The pulverone I have made using this is scary. If I ignite a gram of it inside of my garage, the garage door will thump every time. I think this is from the pressure increase in the room. I can't imagine flash powder being that much faster than this stuff. I am testing a salute tomorow which is considerably bigger than any shell I am likely to make. If it is loud enough then I have no need for flash powder. I am hoping for a real thundering boom which would be great for a big finale.

The salute is a 25 mm id, 20 cm length tube with a thickness of approx 1 cm. I used epoxy glue and hardner to form it. I have created a clay plug which is about 1 inch thickness and a wooden plug on the other end. I then folded over the carboard to cover the ends and it is glued down. I then spiked the salute with lots of string and glue. It is just over half full of 40 mesh pulverone. It has a 3 mm fuse hole and the fuse is a foot long.