Cement mixer cleanout

[metricmonkeywrench]

I found a deal on a used but in decent shaped cement mixer (its an old Sears) online and picked it up today. Been wanting one for a while but really didn't want to pay full price for something that will just sit most of the time, even from the cheap tool outlets.

The downside is that one of the previous owners let a good amount of concrete set up in the lower 3rd of the drum. Short of renting either a demo hammer or jackhammer is there some magic method to clean out a drum or am in in for a long bout with a masonry drill, hammer, chisel and sweat?

Attachment 265919

[DGV]

keep it wet and use a brass or lead hammer hitting the outside while machine is running. Be careful , the heavier the better. 4lbs min. plan on a few hours of work.

[Atonic]

Calcium chloride, I think. Not sure what it would do to the drum.

[Winger Ed.]

Beat on it where the 'rock' is with a big hammer to get a vibration going like ringing a bell. A lot should fall off.

Or, if there isn't too much in there, use it like it is.

[country gent]

You might try dry tumbling some rocks or short chunks of steel in it will be loud but may slowly break up the concrete. One place for info would be the concrete yards that deliver by the truck and ask what they use.

If its a third full you may have to break it up some just to get it out and be able to handle it.

[Bazoo]

Freezing water in it might offer some cracking and releasing.

[bikerbeans]

C4.

BB

[Gtrubicon]

I have been a licensed tile contractor for more than 20 years, I have several mixers of different types. the way we clean our mortar mixers is to put a 5 gallon bucket of clean 3/4 gravel, crushed not round river rock, a gallon of muriatic acid and 5 gallons of water and fire up the mixer, the acid dissolves the cement. When done spray the mixer with water to neutralize the acid. We use a cheap air hammer to break up the big build up prior, don’t beat the outside of the drum with a hammer, it will dimple the drum, it gives the cement a great place to bond to, makes your next clean out more difficult.

[Pressman]

From someone who had to clean out a 6 yard mixer, the only thing that works 100% is a jackhammer.

Beating the outside runs the chance of damaging the drum.

[15meter]

I think myth busters did an episode on this, if I remember correctly, they had to resort to high explosives.

Wasn't much left of the mixer but it was a pretty impressive display of instantaneous disassembly of a cement mixer.

[wildwilly501]

I know a guy who got a drum off a truck for scrap that was half full.He burnt it out said it worked I don't know how long it took. I don't think it falls out but does weaken it a lot.Doing a search shows some danger of doing it says it can explode

[NyFirefighter357]

https://youtu.be/Gxm_qpKh7Jw

[JonB_in_Glencoe]

Note to self: Do not buy a cement mixer for cheap, that is partially full of cured cement, thinking I can clean it out easily.

[15meter]

https://youtu.be/Gxm_qpKh7Jw

But it worked! No more concrete in the mixer

[FLINTNFIRE]

I used ospho to clean one , the acid attacks the concrete , Gtrubicon posted above try that first .

[Plate plinker]

I have been a licensed tile contractor for more than 20 years, I have several mixers of different types. the way we clean our mortar mixers is to put a 5 gallon bucket of clean 3/4 gravel, crushed not round river rock, a gallon of muriatic acid and 5 gallons of water and fire up the mixer, the acid dissolves the cement. When done spray the mixer with water to neutralize the acid. We use a cheap air hammer to break up the big build up prior, don’t beat the outside of the drum with a hammer, it will dimple the drum, it gives the cement a great place to bond to, makes your next clean out more difficult.

This works well.

[NyFirefighter357]

But it worked! No more concrete in the mixer

I love watching that video, I remember watching it when it first aired. It's great to post to questions about removing cement.

https://youtu.be/Gxm_qpKh7Jw

[bedbugbilly]

IMHO banging on the outside of the drum is never a good idea as it is too easy to get carried away and you will end up with a dimpled drum. Try what the pros above suggest . . . just be careful with the muriatic acid - use goggles and rubber gloves and when you are done and have your drum clean, make sure it and your mixer are well cleaned . . if not, the muriatic acid will rust it and any other metal around it.

My Dad started myself and my brother out at a very young age - we had a stationary mixer and later one that went on the back of the 8N Ford that rally worked slick. We mixed a lot of cement for projects on the farm and he had us shoveling to help and to learn how to do it. The one thing he drilled, hammered and pounded into us was to CLEAN the mixer up completely when the job was done. Never ceased to amaze me when we were at farm auctions and others and there would be ce,emt mixers and you'd look into them and they weren't cleaned properly and like the one you bought. Sweat and provably a few swear words along the way but you'll get it cleaned out and you'll certainly appreciate that you have it when you need it. Good luck!

This reminds me of an incident back in the late 80s. We had a contract for trimming out a number of houses in a subdivision that was being built. Behind the house we were working not they had dug a basement and were ready to pour the footers. We were taking a mid-morning break for a coffee and as we took it, we watched a Reds-mix truck carefully make its way backing up to where it could get the chute in a good place to dump for the footers. It was in the fall - typical rainy wet Michigan weather for the week before. The cement contractors were up on high ground and directing the truck back - thank God nobody was in the basement yet because when they got the truck where they wanted it and the driver got out, in less than 30 seconds the wall of the dug basement gave way and all of them jumped bak.
We couldn't believe what we were watching but that large Redi-mix truck slowly slid back as the wall of the dug basement collapsed and slid right down into the basement - with a full load of cement on board. Thankfully no one was hurt but they ended up having to bring in a large crane in order to get the truck out and I have often wondered just how they ever got that full mixer of cement cleaned out - if they ever did. They weren't able to get a crane there until the next day so that load sat well over 24 hours.

[Mal Paso]

Have you seen the Beirut Explosion Videos? 27,000 Tons of Ammonium Nitrate.

[brass410]

I have been a licensed tile contractor for more than 20 years, I have several mixers of different types. the way we clean our mortar mixers is to put a 5 gallon bucket of clean 3/4 gravel, crushed not round river rock, a gallon of muriatic acid and 5 gallons of water and fire up the mixer, the acid dissolves the cement. When done spray the mixer with water to neutralize the acid. We use a cheap air hammer to break up the big build up prior, don’t beat the outside of the drum with a hammer, it will dimple the drum, it gives the cement a great place to bond to, makes your next clean out more difficult.

this works. also if you take hammer drill and judiciously bore into the thicker areas carefully (as to not damage the steel tub) this will speed the process up