Dextrin: Ball milling in vs screening in
Retrieved: 12/28/2014
Last Post: 09/26/2002
Mike
9/18/02
I've been screening in dextrin after ball milling my
pulverone. I have a question about ball milling it in vs screening it
in.
For my standard rocket mix, I toss in the chunky C, the KNO3, and the
S, and ball mill away for several hours (in a heavy duty Sponenburgh
mill). It works well (well enough) and it's adequate and consistent.
I know that ball milling S + C before milling in the KN03 is supposed
to help performance. In that same manner, would ball milling in the
dextrin have an adverse affect (i.e. to finely incorporated in the
mix) or should it be OK.
It'd be great to save the screening steps for comps that otherwise
don't need it. If it wouldn't have an adverse affect on performance.
I'd appreciate the group's advice - particularly since my products and
experience may not notice the effects ... yet. And I'd like to avoid a
poor performing process from the start.
Also, is Dextrin "used up" after binding or, if re-wet, will it
facilitate binding a second time? Say in re-milling some granulated
pulverone that already has dextrin in it. Could I just re-wet and
press/cut stars/small comets with it and have them bind - or would I
need to add extra dextrin (and thus also affect the fuel ratios) ?
Thanks! Mike
Lloyd E. Sponenburgh
9/19/02
Ball milling with dextrin will almost certainly cause your powders to clump
unless your materials are dessicated and you keep the milling jar quite
cool.
Dextrin tends to get stickier per unit of moisture as the temperature rises.
An alternative would be to mill the powder without dex, then add the dex and
let the mill run only a few moments to disperse the dextrin. Expect to see
a LOT of the dex bound to the milling media and jar walls.
YES, you can re-wet dextrin-bound mixtures. I don't know how many cycles of
wet/dry dextrin will withstand, but I've re-wet some comps three or four
times without a binding failure.
LLoyd
> From: Mike
> Reply-To: rec.pyro.s...@privatedata.com
> Newsgroups: rec.pyrotechnics
> Date: Thu, 19 Sep 2002 01:34:31 GMT
> Subject: Dextrin: Ball milling in vs screening in
- show quoted text -
Mike Swisher
9/19/02
It isn't really necessary to ball mill your polverone. I never do. Here's the
recipe:
18 lbs. saltpetre
4 lbs. airfloat charcoal
3 lbs. sulphur
1 lb. 12 oz. dextrine.
Sieve saltpetre, sulphur and dextrine individually through 40-mesh. Blend
with the hands, then weigh out the charcoal. Sieve the mixed
saltpetre/sulphur/dextrine onto the charcoal through 20 mesh. Blend by
hand; sieve the resultant mixture 3 times through 20-mesh.
Have two galvanized wash tubs ready for damping the polverone, a large
metal scoop (like used by bakers for flour), a 2 x 3 foot screen made with
3x3 hardware cloth for granulation, and half-a-dozen 2x3 foot
screen-bottom trays lined with 30# kraft paper for drying.
Weigh out 6 lb. of water and place in a closed pot. Set this on a hot plate
or stove to boil. Place the mixed composition in one of the wash tubs.
When the water is at a rolling boil, add it to the composition and stir with a
stick till the mixture has cooled sufficiently to be handled with the hands.
This will happen quickly as the dissolution of saltpetre in water is highly
endothermic. Make sure that the water is evenly blended into the
composition. It should be thoroughly wet but not soupy. Using the hands
form softball-sized pieces and rub them through the 3x3 screen into the
other tub.
When all has been passed through the screen, place it atop the first wash
tub and, using the scoop, start running the graulated mix back through the
screen. Do NOT mush it back up into balls, but handle it carefully so as to
keep it loose and granular. When it has all been passed through the
screen back into the first tub, repeat the process a third time as before.
When this is done, granulate a fourth time onto the paper-lined screens.
By this time it should be forming up into nice round granules that have
little tendency to stick to each other. After it has been put onto the screens,
allow to set for 30-40 minutes; finally, re-granulate it a last time onto fresh,
dry paper. One batch should fit on five 2x3 foot screens; the sixth is for use
in the final granulation, as this is the first to be lined with dry paper and to
receive the powder on the final re-granulation. The just-emptied screen is
then re-lined and receives the powder from another, etc., leaving five
screens filled and one empty.
I processed 3 batches of this size last Sunday afternoon, taking about 3
hours, start ing with laying out the equipment and finishing with it cleaned
and put away. I will do the same this weekend and the next. One never
has enough polverone!
Allow the polverone to dry in a shady, dry place. When it is dry it should not
stick to the paper and should be relatively free flowing, without clumping
into hard masses that require effort to break up. If it has been properly
made it should resemble 2FA in granule size, and be quite fast. I have
used it (not as regular practice, but as an experiment) to lift 3" and 4"
mines and 1-break shells. You just have to use a little more than you
would of 2FA.
I divide mine into three "cuts" - coarse, which passes 3x3 and is retained
on 8x8 hardware cloth; medium, which passes 8x8 hardware cloth and is
retained on window screen (16x18 meshes); and fine, which passes
window screen. If you end up with too much fine, it is certainly possible to
re-granulate it by adding a suitable amount of boiling water.
In article , Mike says...
- show quoted text -
Mike
9/19/02
Lloyd and Mike - thank you very much for your detailed replies.
This past time, I didn't have problems with the dextrin sticking, but
the humidity was low. I'll watch out for that in the future and
consider adding the dextrin in for just a few minutes. As noted, this
just for expediency when comps don't otherwise need screening and or
can just be 100% ball milled (i.e. BP comps).
And I appreciate knowing I can re-wet the dextrin.
Mike, I really do need to try the precipitation method as you describe
in detail. I have a good sponenburg mill with gallon jars in a nice
safe place, and I can crank out 1kg per jar in a couple of hours. I
have to say I've been "afraid" of the precipitation method and haven't
tried it. I do need to, carefully, get over this and try it so that I
can safely then use the appropriate method for what I'm preparing.
I'll be trying my granulated pulverone as lift this weekend. Likely
only in some star mines as I don't yet screen for size and wouldn't
want the inconsistency of altitude for shells (for safety mostly).
And, I agree, one can never have too much Pulverone.
Many thanks again for the stewardship of the group.
regards, Mike
Kyle Kepley
9/19/02
I've been ball milling dextrin with all my meal and never have any problems.
It doesn't seem to clump worse than when milling meal without the dextrin,
and I live in about as humid of an environment as you can find in America.
Using a Sponen type mill with 6" jars, I mill 300g charcoal with 200g sulfur
for 2 hours, then mill 1000g K-Power for 2 hours. I store these two
components seperately and mill them together only when I need meal, rather
than making a bunch of BP and have it sitting around in storage. 600g of
the KNO3 is mixed with 200g of the C/S mix, adding 40g of dextrin to the mix
if required. This only needs to be milled together for one hour if your
mill is setup correctly. I get clumping problems if I mill longer than
about an hour, with or without the dextrin. The KNO3 causes clumping, and
Florida summers will cause it to clump no matter how much you attempt to dry
it before milling. Using only one or two lift bars in your jars helps
minimize clumpage. Using no lift bars makes your mill less efficient.
-Kyle
"Mike" wrote in message
news:dp9iouknak80p1068qdiocr9cnf1ojicr3@4ax.com...
- show quoted text -
Mike Swisher
9/20/02
Please note - the method I described for making polverone is NOT a
"precipitation method."
It simply involves dampening the mix with boiling water (rather than cold water)
and then granulating. It is what I was taught to do. Use of boiling water for
this purpose is traditional. Such a method was described by Perrinet-d'Orval as
long ago as 1745.
Only enough water is added to dampen the mix to a proper consistency for
granulation. It does not produce a soupy blend that is added to alcohol, etc.,
as in the so-called "CIA" precipitation method, which I do not recommend.
The advantage of dampening with boiling water are two. First, it dissolves the
saltpetre much more thoroughly than cold water will, and allows it to mix more
intimately with the charcoal and sulphur. Second, it dissolves the dextrine
better than cold water will, and consequently it functions better as a binder.
In article , Mike says...
- show quoted text -
deefault
9/21/02
Mike Swisher wrote in message news:...
> Please note - the method I described for making polverone is NOT a
> "precipitation method."
> >Lloyd and Mike - thank you very much for your detailed replies.
> >
> >This past time, I didn't have problems with the dextrin sticking, but
> >the humidity was low. I'll watch out for that in the future and
Mike or anybody:
Has anyone tried SGRS in this application in place of dextrin? Seems
to work great for stars: nice & hard, too, but DOES seem to take a lot
longer drying. I ask because SGRS seems to be easier to find recently
(my personal supplies are now coming from a European source & I no
longer depend on sporadic Asian suppliers. My current sales rep is
based in the Eastern US).
> >Many thanks again for the stewardship of the group.
> >
> >regar
AGREED! Thank you, Mike!
Robert Goodman
9/21/02
"deefault" wrote in message
news:27281320.0209202250.5c293c35@posting.google.com...
> Has anyone tried SGRS in this application in place of dextrin? Seems
> to work great for stars: nice & hard, too, but DOES seem to take a lot
> longer drying. I ask because SGRS seems to be easier to find recently
> (my personal supplies are now coming from a European source & I no
> longer depend on sporadic Asian suppliers. My current sales rep is
> based in the Eastern US).
What's SGRS?
Kyle Kepley
9/21/02
I made a batch of black match using SGRS in place of dextrin. The meal
slurry had a thick and creamy consistency compared with a dextrin based
slurry, and it really did not want to let the string absorb much water. It
took a lot of work to get the slurry worked into the string. The match took
a very long time to dry, over two weeks, which gets annoying because the
frame takes up a lot of space in my shop. The long dry time also resulted in
slight nitrate crystallization. The resulting match seems to work ok and
has the interesting quality of being able to be bent without cracking. It
would probably be good for crossmatch, since it is very stiff and wont
buckle if you try to push it through an undersized hole. It seems to hold
up in high humidity better than dextrin based match as well, since it
doesn't pull the moisture out of the air.
I've used SGRS slurry prime too, but again the long try time gets annoying.
One nice thing is that you can store the prime and the BP will not drop out
of suspension the way it usually does with dextrin bound prime slurry. So
it remains just as thick as the day you made it. After several weeks it had
not spoiled yet, but I think it did eventually get funky after a few months.
If you don't mind the extended dry times, SGRS is the ultimate binder for
round stars. I haven't tried it with cut stars, but I imagine the dry times
would be really long due to the additional amount of moisture required to
make cut stars.
-Kyle
"deefault" wrote in message
news:27281320.0209202250.5c293c35@posting.google.com...
- show quoted text -
George Burkhard
9/22/02
Soluble Glutinous Rice Starch
"Robert Goodman" wrote in message
news:amivfa$64u0d$1@ID-140940.news.dfncis.de...
- show quoted text -
Robert Goodman
9/22/02
> What's SGRS?
Never mind, just figured it out -- soluble glutinous rice starch. but I
see there's an answer waiting anyway.
Rob Peacock
9/23/02
Hey Kyle,
When you made the match with SGRS, did you boil the string before
adding it to the slurry? I would think that by boiling it to remove
the sizing and whatever else might have been in it, you might reduce
the surface tension.
--->Rob
On Sun, 22 Sep 2002 01:50:08 GMT, "Kyle Kepley"
wrote:
>I made a batch of black match using SGRS in place of dextrin. The meal
>slurry had a thick and creamy consistency compared with a dextrin based
>slurry, and it really did not want to let the string absorb much water. It
>took a lot of work to get the slurry worked into the string. The match took
>a very long time to dry, over two weeks, which gets annoying because the
>frame takes up a lot of space in my shop. The long dry time also resulted in
>slight nitrate crystallization. The resulting match seems to work ok and
>has the interesting quality of being able to be bent without cracking. It
>would probably be good for crossmatch, since it is very stiff and wont
>buckle if you try to push it through an undersized hole. It seems to hold
>up in high humidity better than dextrin based match as well, since it
>doesn't pull the moisture out of the air.
Mike Swisher
9/23/02
In article , "Robert says...
- show quoted text -
SGRS is an abbreviation for soluble glutinous rice starch, or "miziko." It is
commonly specified in Japan as a binder.
As for its use in match, I do not have any experience of it, but many old
fireworks men in this country used laundry starch rather than dextrine as a
binder for match slurry. It worked well.
>
Kyle Kepley
9/23/02
I used dry cotton string, which always works well with the dextrin based
slurry. I think I tried pre-wetting the string a long time ago and didn't
have good results. I seem to remember that the wet string prevented the
slurry from sticking to it very well, resulting in only a thin coating on
the final match. The method I use now was given to me by someone in the
fireworks industry who makes all their match by hand. I wrote about it in
the May edition of Passfire.com.
-Kyle
"Rob Peacock" wrote in message
news:15cuoug88d9vj3j2dbhcbqg1h8oatt733r@4ax.com...
- show quoted text -
Mike
9/23/02
I have a question about SRGS.
Since Amylopectin seems to be the main compound in SRGS that makes it sticky.
Has anyone tried simply using Amylopectin as a binder for round stars and such?
Mike.
- show quoted text -
Richard Ogden
9/23/02
Probably...but why? SGRS is cheap.
"Mike" wrote in message news:3D8F5B2F.194DCFC1@verizon.net...
- show quoted text -
Mike
9/24/02
True, but not all people prefer beer some prefer whisky.
- show quoted text -
Richard Ogden
9/24/02
Not a good analogy IMHO. Beer and whisky don't taste alike or ACT alike, and
they're not anything like the same strength. A cold beer or two is great on a
hot day, when whisky would knock you down quick - on a cold night I'd prefer
whisky, thank you very much. And you're dealing with the very powerful
subjective senses of taste and smell.
But if you want an alcoholic comparison between SGRS and Amylopectin, here's a
more realistic one: Take a good aged whisky, redistill it and run it through
activated charcoal to remove all the flavor, then charge a lot for the
additional processing.
Hey, if you want to pay more for the same effect (assuming it works as well),
that's your choice of course. I spent quite a bit of time looking around (on the
internet and in Oriental grocery stores) before Russ started carrying it <
http://www.pyrosupplies.com/default.asp?CtgID=24 >. Now that it's available
here, at a reasonable price - and it works just fine - I don't see a reason to
look for a more expensive substitute that might (or might not) work as well.
-Rich
"Mike" wrote in message news:3D901A3C.7503D507@verizon.net...
- show quoted text -
Mike
9/24/02
According Pyrosupplies analysis their SRGS is 97.65% Amylopectin.
So it would seem the purer extract would work just as well.
They have a 10 Lb. minimum order for SRGS at $46.00 not including shipping.
Which is quite a lot in quanity and price.
Now if Amylopectin is readily available at say the local heath food
store or brew shop you could save some money.
- show quoted text -
Kyle Kepley
9/25/02
I doubt you can find a pound of ANYTHING in a health food store for under
$4.60/lb. Since increased purity always comes with increased costs, even if
you could find pure amylopectin it would surely be more expensive than what
PyroSupplies is selling it for.
Pyro is an inherently expensive hobby. We are essentially setting fire to
perfectly good chemicals, turning high quality papers into confetti and
shredding expensive balls of twine. But what better way to burn your money!
-Kyle
"Mike" wrote in message
news:3D90B624.5AC569D7@verizon.net...
- show quoted text -
Jeff
9/25/02
Mike wrote in message news:<3D90B624...@verizon.net>...
> According Pyrosupplies analysis their SRGS is 97.65% Amylopectin.
> So it would seem the purer extract would work just as well.
> They have a 10 Lb. minimum order for SRGS at $46.00 not including shipping.
> Which is quite a lot in quanity and price.
> Now if Amylopectin is readily available at say the local heath food
> store or brew shop you could save some money.
Try Instant ClearGel available at www.kingarthurflour.com for $2.95
for 8oz. I recall seeing a post by an authoritative source that
indicated this should be a valid substitute for SGRS. Skylighter
carries a product called Starpol which is regarded as a direct sub for
SGRS.
Jeff
Don Thompson
9/25/02
That is still 6 bux a pound.
--
Don Thompson
Ex ROMAD
"Jeff" wrote in message
news:9ba48946.0209250947.2586276a@posting.google.com...
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Richard Ogden
9/25/02
Here are some other possibilities:
http://www.vegrains.org/english/varieties_waxycorn.htm
http://www.ars.usda.gov/is/pr/2002/020305.htm
-Rich
"Kyle Kepley" wrote in message
news:NYkk9.2691$u56.200285@newsread1.prod.itd.earthlink.net...
- show quoted text -
Mike
9/25/02
Yup, it looks like there are a few places that have the stuff. The instant Cleargel
is the one to get.
http://www.theingredientstore.com/index_copy(2).htm
http://www.fcs.uga.edu/pubs/current/FDNS-E-P-1.html
http://waltonfeed.com/cgi-bin/cart.pl
- show quoted text -
Mike
9/25/02
Mike Swisher wrote:
>
> As for its use in match many old fireworks men in this country used laundry
> starch rather than dextrine as a binder for match slurry. It worked well.
No wonder it works as a good binder for cotton black match.
The Best type of Laundry Starch:
The best starch is derived from rice. This starch imparts a high quality finish
to natural fibres. In the liquid or suspended form, it does not readily congeal
after cooking and gives a satin-like finish to the fabric. For the customers with
100% cotton shirts who like heavy starch, a larger concentration of starch will
give the stiffness they like. Other starches such as those made from wheat or
corn are less expensive but do not impart the same high quality finish as does
rice starch.
Jeff
9/26/02
"Don Thompson" wrote in message news:...
> That is still 6 bux a pound.
>
Cheaper than Starpol @ snerds, and certainly able to meet the poster's
needs for a smaller quantity than the 10 pounds required at
pyrosupplies. Just tryin to be responsive to the poster's needs.
Somethin tells me that straight pure amylopectin might be a bit more
expensive than the Instant Cleargel.
Jeff