Cement Mixer Advice

[Stan Coryell]

Im still enough of a tight a@@ to diy but the next few days I really regret it

I'm with you!

My oldest is 14. For him and I? Probably 10 hours. 5 minutes a bag and you still have to finish it. $700 in bags plus the mixer. To save $300? Hard pass.

Three years ago I poured four 24 x 24 x 12 footings in my crawl space. 30 or so bags. That's my limit.

 

[Tgrasher]

I have the Harbor Freight mixer you mentioned and it works very well for small jobs but unless your superman, I wouldn't advise attempting what your planning with it. Maybe if I was 25 yes old.

 

[MarkB_MI]

No way would I mix two and a half yards of concrete. Years ago I did a yard and that was enough to convince me to eat the small batch charge on future projects.

 

[sms]

I have used the one and two yard trailers from a precast business many times, great for small jobs. Check around your area and see if they are available.

 

[Fred Werring]

Im still enough of a tight a@@ to diy but the next few days I really regret it

Yep

Been several years ago, but somebody on these forums said they welded in a couple short paddles in the bottom of the HF mixer as they weren't happy with how it mixed.

Only mixed a few bags of concrete with mine. Mostly gets used for mixing wormer in feed, innoculating clover seed, mixing homebrew potting soil, stuff like that

 

[ratface]

I had a HF one long ago and hated it. It mixes really slow and only holds a couple of bags. I can mix faster by hand with a wheel barrow. Most I ever mixed by hand is 45 bags and will never do it again.

 

[Stephen Newell]

I have two projects slated for this fall that involve pouring cement slabs. One is inside an existing building and one is a new slab that is going to be the foundation for a covered butchering platform. All together, I'm looking at around 200 square feet of four inch deep concrete.

I'm looking for advice about buying a small cement mixer (like the Central Machinery 3.5 cu ft Harbor Freight mixer at $270) versus renting something or calling a redi-mix truck. It's been 8 or 9 years since I poured anything other than for a fence post. I'm thinking if I had the mixer, then there are several other small jobs I could do around my place. Anyone have experience with these cheap mixers, good or bad?

I have the Central Machinery mixer and it will mix 2- 80lb bags of cement at a time. I've mixed many hundreds of bags of cement with it over the years and still works great. 200 sq. feet looks like 112 bags to me. I hope you have a front loader to lift the bags up to the cement mixer. Otherwise I think it would be easier to mix the cement with a hoe.

 

[Keith True]

Six years ago when I rebuilt my house I had to pour 10 piers for the overhang.I have a big pile of concrete rubble in the bushes,so I picked out 10 slabs,about 3X3,dug the holes,and set a slab in the bottom of each one.Got them leveled up and dry stacked concrete blocks up to the level I needed.Plumbed them up,and dropped a piece of rebar in each one.I have two old Sears mixers,and set them both up near the piers.I have three Bobcat buckets and I filled one with stone,another with sand,and the third with bags of portland.I lined them up in front of the mixers,and it still killed a couple of days pouring those piers.I have hundreds of blocks out there,so using some to make my sonotubes was a no brainer.

 

[Texasmark]

I had a 3.5 when I first bought this place.....which is now a farm....I think???? Working alone the 3.5 will keep you busy but it works. Just ensure you clean it up good EVERY time, after using it.

 

[Turkeyfoot]

I have two projects slated for this fall that involve pouring cement slabs. One is inside an existing building and one is a new slab that is going to be the foundation for a covered butchering platform. All together, I'm looking at around 200 square feet of four inch deep concrete.

I'm looking for advice about buying a small cement mixer (like the Central Machinery 3.5 cu ft Harbor Freight mixer at $270) versus renting something or calling a redi-mix truck. It's been 8 or 9 years since I poured anything other than for a fence post. I'm thinking if I had the mixer, then there are several other small jobs I could do around my place. Anyone have experience with these cheap mixers, good or bad?

I appreciate all the excellent input. On the interior pad, I plan to do it in sections. I think I'm going to buy the mixer and do those sections myself. But for the outside butchering platform, I believe I'll have that done by pros.

One thing I liked about the advice was the alternative uses that were mentioned like mixing soil, innoculant, feed. Easier to justify buying, maintaining, storing something if it will see some degree of frequent use.

 

[Keith True]

I don't know what it's like where you are,but around me there was a Sears mixer in every other backyard.I have two that are working,and two more in the scrap pile that are probably good.I did actually pay money for one of them,it was a 20 year old mixer bought new from Sears and never used,I did have to pony up $30.to buy that one for at a yard sale around 1988.I use them mostly now to derust things.Pour some sand and a bunch of nuts and bolts in with whatever I want cleaned and let it run.I also have a mixer for pouring post holes.It's like a wheelbarrow,single wheel in the front,with the tub shaped like a mixer truck.Mix the concrete,wheel it up to the hole,and dump it in the hole with no loss or mess.

 

[Southern Ray]

ps there are only 3 things you need to know about concrete' 1) it gets hard, 2) it cracks, and the most important in my opinion 3) hire it done

One more, you work it or it will work you.

 

[ThreeEdwardsM]

It takes 45, 80-lb bags to make one cubic yard of concrete. That's the upper limit of what I would want to hand-mix. Your job is about 2.5 cubic yards. I'd get that delivered, personally.

If you want a conventional mixer, used is the way to go.

The MudMixer Evolution continuous machine looks interesting, but I have no experience with it.

I had an experienced concrete crew in my neighborhood for over a month recently, and my biggest takeaway watching them is the same takeaway I have whenever I watch someone good at their labor - it's 85% prep work.

 

[Dopp Creek]

You mean they'll mix it at the plant then load it in a trailer mounted mixer that you tow to the site? That's an option I didn't know about.

I did that once at the old farm, which used to be a dairy. I wanted to fill in the manure gutter and there was a rental yard 8 miles away. I can't remember if the unit was 1.5 or 2 yards, but it was a trailer mounted mini version of a cement truck. A Honda engine powered it, backed it up to the barn and reversed the rotation to fill a wheel barrow. It was slick and easy. Rental yard moved and no more concrete.

I once mixed 80 80# bags by myself in a 6 bag mixer on an 85 degree afternoon while my wife and son poured and screeded it. Everyone was exhausted and no one was happy with the results. Live and learn.

 

[lodoc]

ps there are only 3 things you need to know about concrete' 1) it gets hard, 2) it cracks, and the most important in my opinion 3) hire it done

One more, you work it or it will work you. And it turns white...

 

[Keith True]

I don't know of any places around here that does the one yard mix trailer thing anymore.My dad used to use one of those a lot,for small customer projects.Great idea for footings,patios,filling sonotubes for additions and breezeways,etc.He's arrange for me to haul the wagon,as they wouldn't let anybody hook up to a vehicle that they deemed too light.After a couple of problems the law got after them.In N.H.anything 3000 pounds and higher needs brakes.Really clobbered their customer base when they had to make sure the customers trailer brake setups were actually functioning.Dad really missed it whan they shut down.He never minded mixing and pouring the concrete,he just didn't like hauling the mixer to a job,rassling it around,and hauling bags and bags to the job.

 

[DanielW]

I have several cement mixer apparati. One three-point model, one large gas-powered one (a little larger than the three point one), two smaller gas powered ones (just a little larger than your standard homeowner-sized mixer), and a couple of 120V 3.5-yard homeowner mixers. I've poured a lot of concrete with them over the years - footings, barn wall supports, smaller pads, oodles of sono tubes, etc.

With that being said, I've only used any of then once or twice in the last 5-6 years. And I've poured more concrete in the last 5-6 years than I had in the previous 10 years. For 90% of jobs, I just don't deem it worth it to mix myself. And that's with us owning our own gravel pit: The county rents our pit, screens and separates the sand/aggregate, takes what they need for road maintenance, and we can use as much as we want for free. So the sand and gravel is free for us - All I have to buy is the portland. But it's still not worth it (most of the time).

For a couple sono-tubes or small footings, I'll use one of mine. Usually the three-point one, as it's convenient, I can mix wherever I want (near the house if I want running water or near the pit if I don't want to haul sand/gravel to the site) and drive to the pour site as it's spinning away. But for any job larger than about a yard, I'll just get in a truck. With you going 2.5 yards total, I'd just get it formed up and call a truck in to do both at once. Job done in about an hour or two at most with minimal effort on your part. If you have access to free sand/gravel, it might... might be worth it to mix yourself. But if you have to buy the sand/gravel, you might want to price out a truck. Even at bulk sand/gravel pricing, the pre-mix truck is usually only a smidge more.

If you were doing it yourself, I'd also want to go more than 4". If it was a solid single pour, lightly loaded and had appropriate mesh, the 4" might be fine. But when doing yourself in a smaller mixer, each of those pads is going to take a few hours to pour, bit by bit. You may not have any 'cold-seams' per-se as the previous batch won't be fully cured by the time you dump the next batch on. But it won't be a continuous single cure, and will be accordingly a little weaker. I'd want to go 6" if I was doing it myself. Plus if doing yourself, it's not going to be air-entrained (unless you can find somewhere that sells an air-entraining agent - but I haven't been able to buy any for years). If it's not air-entrained, it's not going to handle freezing/frost nearly as well.

Around here, the minimum order size for a standard truck is 3 yards. But there's also a chap in the next town over with a smaller mixer on a single-axle 5-ton truck that does smaller loads (anything up to 3 yards - but he is a bout 15% more per yard, so only worth getting him in if a large truck can't get to the site). The price around here for the standard truck is about $240 CAD per metre - about $183 CAD per yard ($130 USD). No delivery charge for 3 yards or more. That's for a 32C2 mix (32 MPa = 4600 psi | C2 = air-entrained).

Assuming it's a similar rate and minimum charge in your area (and assuming you're in the US), a 3-yard load is going to cost you just around $400. For me, that's a no-brainer. Even if it cost 50% more at $600, that would still be a no-brainer for me. Get the truck in, get both pads done in an hour or two. Much stronger mix (most home-grown mixes are lucky to be 3000 psi at best), it'll be one continuous cure, air-entrained, minimal back-breaking labour on your part, no lugging separate loads of sand and gravel around and approximating proportions, and far less clean-up. If you stick with 4" you'll have an extra half yard to put somewhere. But there's no shortage of uses for concrete around a farm. Myself: I'd just make the pads a little thicker and use it there. Or at least a little thicker at the edges for a better load-bearing grade beam.

 

[cwtech]

If you are working alone, do not try to do it yourself.
....If you have a lot of free/cheap help, then it's possible to do it onsite with a small mixer.

Google "small batch concrete delivery" to see what is available in your area.
....Some companies have small 3.5 yard trucks to deliver small batches of pre-mix.
.....Some companies will come to location and mix only what you need onsite.

 

[dlbuck]

I worked road construction, operated machines that poured seven foot tall barrier to two foot thick x sixty foot wide airport runways to six x six x two inch thick patches. If you have the money do as the late great Andy Griffith told Aunt Bea " JUST PAY THE MAN" .

 

[Stephen Newell]

I think the job is doable if you are fit enough. When I was in my 30's I poured a footing for a bridge on my property by hand. There was very little electricity there and no water. I had to run a hundred yards of extension cord to the area so I could use an electric pump to pump water out of the pond. I mixed 120 80lb bags with a hoe and shoveled it in. Took me all day but it worked. By the time I got the forms built for the rest of it the ground was solid enough I could get a cement truck in there to finish the pour.