Coffee mill question

[kpknd]

I picked up a Krups coffee mill yesterday and tried it out. I milled som PN and sulfer (seperatly of course) and the darn stuff was adheerd to the sides of the mill with static electricity. Does this happen to anyone else ? It was a trick to clean out. Oh...Happy new year.

Edited December 29, 2013 by kpknd

[mabuse00]

You should use separate machines for fuels and nitrates.

 

They are mostly air cooled and at the same time the milling vessels leak dust that accumulates within the machine.

 

 

the darn stuff was adheerd to the sides of the mill with static electricity. Does this happen to anyone else ?

 

Yes. Especially if your stuff is very dry. It's plastic after all...

[ddewees]

I bought three of these from Wal-Mart, and they work great. They're essentially air/water tight... and comes with two blade assemblies and several containers. Very easy to clean.

 

http://mobile.walmart.com/m/phoenix#ip/FARBERWARE-17-Piece-Rocket-Blender-Stainless-Steel/22903915?type=shop-by-department

[kpknd]

Fuel and nitrate, I will get another one.

[Mortartube]

Put either torn paper strips or a little cat litter in the mill and give it a few whizzes to clean it.

[toolbox]

Always good advice, use separate machines for fuels and nitrates!

[LambentPyro]

Just be careful using any of these. Remember what happened to Mumbles, he didn't have any mixed chems in there besides Charcoal he was grinding up and it got so hot it lit up an entire nearby batch of BP. Do this outside (really everything should be done outside anyway) and away from posing a threat to yourself, others, and property.

 

Be safe and think twice.

[mikeee]

Certain materials will release a large amount of static charge while grinding.

Grind several batches and don't worry about cleaning between each batch.

When you are done grinding what you need, wipe it out with a paper towel.

Wood chips or cat litter works good to clean the grinding chamber of residue if needed.

[kpknd]

Thank you for the advice.

[Shadowcat1969]

Grind several batches and don't worry about cleaning between each batch.

That would technically be: Grind several batches of EACH individual chemical and don't worry about cleaning between each batch, UNTIL you move to another chemical.

 

Again, don't use the same mill for oxidizers and fuels, even if you clean it between. I also would make sure you are clear about possible incompatibilities as well, such as not using the same Oxidizer mill for Potassium Nitrate and Ammonium Perchlorate, you really don't want to risk cross-contamination with a lot of stuff.

 

Not trying to be a jerk, Mikeee, just making it (hopefully) crystal clear to anyone new.

[mikeee]

C.C.

[chuck45]

Hi kpknd.

 

When I first started out in pyro I was keen to save money. I tried to get multiple uses from each item, but some things like the grinders that you mention aren't really worth getting dual use out of when it compromises safety.

 

As folks above have stated, get a couple if you can, then if possible, use one grinder for one chemical for as long as you can. Makes life so much easier for a little more expenditure, not to mention safer. If you can, use one grinder for one chemical, if you are using that chemical all the time, like KN03.

 

Plastics can be a pain with the static issue!

[MrB]

Thread hijack, sorry. Just taking a slight detour.

When we talk coffee grinders, we are generally talking about high-speed blending knife types. Now, more "fine coffee" oriented grinders work on the same principle as a pepper mill. I'm looking at a kit of 10, with separate holding jars for the "beans", where all you do is press a button, and they grind, and dispense as long as you keep it pressed. High power, low RPM, so it wont heat up the coffee beens as they go through the grinder, supposedly to save the flavors. adjustable for particle size, so you can get the output as dust from the darn thing. This thing is from a coffee shop that is upgrading, they decided they need higher capacity gear, and i happened to ask what would happen to this unit... "Storage, unless someone wants it." I'm guessing it's going to be pretty cheap. Thing is.... Do i want it? And no, i don't drink coffee. They make a killer hot chocolate, with whipped cream.

 

I'm sort o undecided. Metals i assume isn't very good in one of these, but pretty much everything else should be ok, right?

B!

[Shadowcat1969]

I would think one of those would work ok, MrB, as long as the "dust" is actually fine enough. -325 mesh fine.

 

And one of that type might actually work for grinding MgAl down as well, if you make your own. I wouldn't do any other metals though, I don't think.

 

One might also work for corning of pressed BP pucks, if you can adjust the output size to large enough grain. I'd have to think about it hard before feeding BP into it though.

[MrB]

Not sure about particle size. From what i know, the finest powder it can produce feels like dust, no obvious solids. It should be said, all my stuff comes pre-milled, but you know how it is. When your about to use it, it's not that 100% dust you ordered anyway. Most of it goes away if you screen it a few times, but for consistency... I'm going to talk to them, see what it's going to cost me, how i would need to hook it up, such.

 

Corning BP... Hydraulic pressure onto a splitter, and toss the chunks in here... Could work. Largest patricle size should be in the 2-3mm size, so 2FA, and smaller would be sort of in range. Not sure i i'd dare to.

B!

[Shadowcat1969]

The reason BP corning came to mind was that, from my understand (and I could be wrong), the large scale BP makers use essentially large rollers to run the pucks through to break them up. I'm sure their rollers are either stainless steel or aluminum. As long as your coffee milling surfaces are non-sparking material (I'd think it would be stainless so that they could wash it from time to time), I think it would likely work ok. I'd hope to hear input from someone with more experience first though.

[kpknd]

Can the same grinder be used for diferent oxidisers? Nitrates, chlorates and perchlorates?

[mabuse00]

 

Can the same grinder be used for diferent oxidisers? Nitrates, chlorates and perchlorates?

 

You should avoid cross contamination of your oxidisers unless you know very well what you're doing.

 

Think for example of ramming a BP rocket that has traces of (per-)chlorate in it.

Or chlorate stars with traces of ammonium nitrate or perchlorate...

 

...ect.

 

Get one for nitrate first. Perchlorate is usually airfloat anyway, at least sufficiently fine for most applications. When you move into chlorates just get another one, or better, seperate drums for your ball mill.

 

 

[kpknd]

Thanks Mabuse.

 

I just wanted to make sure. I intend on usin just one mill for PN only and the other for fuels. My tumbler is used for BP ONLY. In the case of chlorates and perchlorates,, they do'nt get used too often and I just screen some onto a newspaper, lay onother sheet over it and roll a wood dowel over it a few times.

[MWJ]

I use a little reason brush to clean my mill out. Works good. I wonder if wiping the inside of the mill out with a Bounce strip would remove the static and still not cause a problem contaminating chemical. Any thought?

[cogbarry]

I have a juicer which is similar to a coffee grinder, it's basically bigger and probably designed with higher quality standards. Until recently, I had only used it for juicing veggies and fruits. I used it to blend a Cajun maranade sauce recently which included fine red pepper powders such as Cayene and Paprika (probably mis-spelled, excuse me). I noticed that the bottom part (the one with the blades) was bleeding a red color from the pepper when washing/rinsing for several iterations of use and washing after this.

 

I don't use this for pyro but it's obvious that the bearings in this part are not sealed very well. I would expect the same from coffee grinders. For me, I like to be aware of the dangers - am I contaminating one oxidizer with another? I doubt this is much of an issue simply because the quantities are small. I would suggest keeping a separate grinder for fuels/oxidizers. It may be a good idea to separate even further (e.g, chlorate and perchlorate). I would hope others will jump in. The bottom line for me is to be aware of the dangers and then do things in a way you're comfortable with.

 

I don't like the idea of having chlorate in my mixes that I'm not aware of. I only have one coffee grinder, I haven't used it for fuels but I have both Nitrate,Perchlorate and Chlorate that are either clumped up or just too course for my needs. Again, I doubt this is much of an issue but there certainly will be some contamination if you use a coffee grinder to mix more than one chemical. I'll let someone else chime in on the potential safety issues/non-issues.

[schroedinger]

Have one seperate for chlorates, never let it see any amonia.

Have one for Fuels one for oxidisers ond one for amonia compunds.

 

The best would be to have one mill for one chemical, but that would need a lot of blenders

Edited January 15, 2014 by schroedinger

[Shadowcat1969]

I actually just purchased one of the "Magic Bullet" blenders with some of this in mind. You can buy extra containers and blade/bases realtively cheaply. I bought the original set (and will use those containers for my kitchen), then a set of 4 extra blades and 4 extra containers and I will be dedicating each set of 4 blades/containers to 4 specific chemicals.

[Carbon796]

I bought three of these from Wal-Mart, and they work great. They're essentially air/water tight... and comes with two blade assemblies and several containers. Very easy to clean.http://mobile.walmart.com/m/phoenix#ip/FARBERWARE-17-Piece-Rocket-Blender-Stainless-Steel/22903915?type=shop-by-department

I have a couple of these, that ddewees linked to. They are far more durable than a standard coffee grinder, and only cost about $5 more. They also hold more material to be processed, than a standard coffee mill. I probably put close too 5lbs. Of Stronium nitrate through one a few weekends ago. That would have over heated and killed a standard coffee grinder. Most of the coffee grinders don't have any venting for the motor, they over heat easily.

I have a separate blade/jar assembly set a side for KP, AP, Strontium nitrate, Barium nitrate, Sodium nitrate, Phenolic resin and one for fuels. Kno3 I knock down in my ball mill.

Edited January 16, 2014 by Carbon796

[cogbarry]

The Magic Bullet is what I was refering to. The blade part is not dishwasher safe. I usually fill the blender with soapy water and run it for a few seconds, then rinse. A good test would be to put some water with food coloring in it and see how many times you see the color bleeding through after use/washing. When I noticed this, it was bleeding out the bottom and not the top side which would come in contact with your mix but in any case, the bearing is not water tight so you could contaminate one chemical with others.

 

I don't use the Magic Bullet for pyro, it's a lot more expensive than the cheap coffee grinders. Coffee grinders are more affordable, especially if you wanted to dedicate them to single chemicals. I think it's relatively safe to use one for oxidizers but these concerns have come to mind. I will check out the blenders ddewws pointed out as the coffee grinders don't have much capacity.