Cement Mixer Milling

[E30 Rocketman]

Anyone ever use a converted cement mixer for ball milling? If so, how
well did it work?

[J***@yahoo.com]

Seems like you have all of the answers, why ask questions?

Post by E30 Rocketman
Anyone ever use a converted cement mixer for ball milling? If so, how
well did it work?

[Auriga]

Hey Rocketman,

There are a few guys who have had good success with converted mixers,
both for use as ball mills and star rollers. I would tend to think
they would not be as efficient as an optimized mill with horizontal
jars. Maybe Lloyd can chime in here,
he is the resident expert on mills. However, any efficiencies that
may be sacrificed would be made up by the increased volume.

Mike

Post by E30 Rocketman
Anyone ever use a converted cement mixer for ball milling? If so, how
well did it work?

[LadyKate]

Post by E30 Rocketman
Anyone ever use a converted cement mixer for ball milling? If so, how
well did it work?

We used one for pulverizing charcoal. It worked fine. As Mike said, it
is not as efficient as a proper mill but it works and we needed the
larger volume.

We used log chain as the media and took the baffles out of the inside
of the mixer - it was a cheap new one from Harbor Freight so
modifying it was easy. Good luck getting the baffles out of a used one
- a cutting torch might be the best starting tool in that case.

We cut a round plywood lid for it and then cut another circle that
just fit inside the opening. That was glued/screwed on the lid and a
big vacuum cleaner O ring was fit on it and bungee corded to the
mixer.

This makes a LOT of noise so be sure you have it in a remote place.
Neighbors will not like you at all if you fire it up in a residential
neighborhood.

Here is a snapshot of it after a few runs: http://tinyurl.com/2ls57b

Here is a closeup of the O ring Rube Goldberg: http://tinyurl.com/2mvkr4

It is best to wheel it over to a large piece of plastic sheeting and
dump it out into a squat garbage can. Everything that misses will land
on the sheeting and you can clean it up easier. Wear clothes you
don't care about when doing this.

Don't get the cheapest Harbor Freight version - it won't turn a drum
with even a short log chain in it without dancing and bogging down.

And, of course, this configuration is not spark safe so milling any
mixed BP in it would be inviting disaster.

You can wedge a plastic bucket into the mouth of the mixer and support
it from the rear and make a star roller out of it. I couldn't find a
good bucket for ours - but then I didn't need a star roller so I
didn't look very hard.

[DanZ]

Kate,

do you happen to know what the item number was on this mixer? I appreciate
your advice, I was about to get that $139 model, the cheap one. Also, any
idea on a part number/source for the perfect o-ring that you had to run
down? I see this as a great charcoal reducer before ball milling...

Post by LadyKate

Post by E30 Rocketman
Anyone ever use a converted cement mixer for ball milling? If so, how
well did it work?

We used one for pulverizing charcoal. It worked fine. As Mike said, it
is not as efficient as a proper mill but it works and we needed the
larger volume.
We used log chain as the media and took the baffles out of the inside
of the mixer - it was a cheap new one from Harbor Freight so
modifying it was easy. Good luck getting the baffles out of a used one
- a cutting torch might be the best starting tool in that case.
We cut a round plywood lid for it and then cut another circle that
just fit inside the opening. That was glued/screwed on the lid and a
big vacuum cleaner O ring was fit on it and bungee corded to the
mixer.
This makes a LOT of noise so be sure you have it in a remote place.
Neighbors will not like you at all if you fire it up in a residential
neighborhood.
Here is a snapshot of it after a few runs: http://tinyurl.com/2ls57b
Here is a closeup of the O ring Rube Goldberg: http://tinyurl.com/2mvkr4
It is best to wheel it over to a large piece of plastic sheeting and
dump it out into a squat garbage can. Everything that misses will land
on the sheeting and you can clean it up easier. Wear clothes you
don't care about when doing this.
Don't get the cheapest Harbor Freight version - it won't turn a drum
with even a short log chain in it without dancing and bogging down.
And, of course, this configuration is not spark safe so milling any
mixed BP in it would be inviting disaster.
You can wedge a plastic bucket into the mouth of the mixer and support
it from the rear and make a star roller out of it. I couldn't find a
good bucket for ours - but then I didn't need a star roller so I
didn't look very hard.

[LadyKate]

Post by DanZ
Kate,
do you happen to know what the item number was on this mixer? I appreciate
your advice, I was about to get that $139 model, the cheap one. Also, any
idea on a part number/source for the perfect o-ring that you had to run
down? I see this as a great charcoal reducer before ball milling...

Post by LadyKate

Post by E30 Rocketman
Anyone ever use a converted cement mixer for ball milling? If so, how
well did it work?

We used one for pulverizing charcoal. It worked fine. As Mike said, it
is not as efficient as a proper mill but it works and we needed the
larger volume.
We used log chain as the media and took the baffles out of the inside
of the mixer - it was a cheap new one from Harbor Freight so
modifying it was easy. Good luck getting the baffles out of a used one
- a cutting torch might be the best starting tool in that case.
We cut a round plywood lid for it and then cut another circle that
just fit inside the opening. That was glued/screwed on the lid and a
big vacuum cleaner O ring was fit on it and bungee corded to the
mixer.
This makes a LOT of noise so be sure you have it in a remote place.
Neighbors will not like you at all if you fire it up in a residential
neighborhood.
Here is a snapshot of it after a few runs:http://tinyurl.com/2ls57b
Here is a closeup of the O ring Rube Goldberg:http://tinyurl.com/2mvkr4
It is best to wheel it over to a large piece of plastic sheeting and
dump it out into a squat garbage can. Everything that misses will land
on the sheeting and you can clean it up easier. Wear clothes you
don't care about when doing this.
Don't get the cheapest Harbor Freight version - it won't turn a drum
with even a short log chain in it without dancing and bogging down.
And, of course, this configuration is not spark safe so milling any
mixed BP in it would be inviting disaster.
You can wedge a plastic bucket into the mouth of the mixer and support
it from the rear and make a star roller out of it. I couldn't find a
good bucket for ours - but then I didn't need a star roller so I
didn't look very hard.- Hide quoted text -

- Show quoted text -

The $139 version is poorly powered. I doubt you would be happy with
it. We had one and it would not turn if it was 1/4 full of chain.
Occasionally, the heavier versions come up on sale for about the same
price and they work better. The whole cement mixer idea is a
compromise - you won't be able to put in enough media to make it
efficient (log chain weighs more than cement/water), it turns slowly,
and it is very noisy. The advantage is it can hold a lot more charcoal
than a hobby mill. Eliminate the reliability problem by getting one
that will last a long time - that means a heavy-duty one. Load it
lightly, turn it on and leave it overnight (or overday if you are near
anyone who cares) and you'll have a fair amount of charcoal dust,

You can use one from an estate sale if it has been properly kept. A
good sturdy base is what you are looking for.

I forgot where we got the O ring... However, Ace Hardware sells all
kinds so I'm sure you could get one of them for a couple of bucks.

BTW: The $139 one is on sale for $99 every few months - it would make
a good star roller if you could find a bucket to fit it - I would find
the bucket before I bought the mixer, though.

[Bill K]

What I do with my 3 1/2 foot Cement Mixer, load it up with around 20lb
- 25lb of lump Charcoal, throw in 10 - 12 bocci balls, cover the mouth
with a black garbage bag and secure it with a bungee cord. 2 (noisy)
hours later you have Airfloat Charcoal. I can grind up 60-75lb in 6-7
hours.

Bill

[Thomas N.]

I heard Dr X uses one to mix flash but I can't confirm that. But then
again, he probably make 200 + lbs per year so why not throw caution to
the wind??

Thomas

[f***@cableone.net]

Post by Thomas N.
I heard Dr X uses one to mix flash but I can't confirm that. But then
again, he probably make 200 + lbs per year so why not throw caution to
the wind??
Thomas

Jack Drewes wrote up an article some years back that described Thomas
"Pops" Dutcher's method of producing cherry bombs and silver
torpedoes, at the time quite legally, while he worked for a large
fireworks manufacturer. The "method" involved, among other techniques,
the use of a lightly modified concrete mixer whose open end was
pointed, cannon-like, out a shattered window at one end of an
abandoned wing of their fireworks plant.

I'm guessing that concrete mixers, over the fullness of time, have
been pressed into all manner of applications with only a few having
anything to do with concrete or mortar.

Tom C.