Mixing portland cement

[jwholden]

OK, I usually buy a couple of bags of premixed mortar mix when I need to install a few belgian block. However, I've got a bit more to do on my next project. I was reading the 94 lb bag of PORTLAND CEMENT and they really didn't have any recommendations. The guy in the store said 1/2 bag to 15 shovels of mason sand.

Does this sound right?

What is a good ratio of so many shovels of portland to so many shovels of mason sand?

Thanks for the help,

John

[diginahole]

4 sand : 1 cement

[jwholden]

:cool:

Thanks for the info. That's where I was thinking it would be.

John

[Stonehenge]

Isn't that roughly what the 15 shovels would give you, in terms of ratio? Are has it been too long since I've mixed a batch?

[BJR]

You should always measure your quantities with a bucket.

On many occasions I have had to go back and fix jobs where an employee has used a shovel to measure the quantities and has made a weak mix. A shovel of cement from a bag is always smaller than a heaped shovel of sand.

We use a 10L bucket.

[Stonehenge]

2.64 gallons for those non-metric folks. ;)

My mason has me mixing 2 X 5 gallon pails (37.9L) with a bag of Type M mortar (50# bag, I believe) for the limited mortar work we've done so far.

BTW - BJR - I saw a picture in a magazine of some limestone (white stone) with dark grey mortar joints. Didn't look all that nice. Made each stone look like it was an island in the wall.

[BJR]

Exactly right.

You want the stone to be the feature, not the joints.

[jwholden]

The bags of portland around here are 94 lbs. We ended up going with 1/2 bag of portland to 20 shovels of sand and I told my helper to mix it til it formed balls. If he got it too wet I had him add 1 shovel of portland and 4 sand to dry it up. It seems to me that to me that about 5 bags of portland is good to mix with one yard of sand. It amazes me how far a bag of portland will go. I'm sure I could probably have lightened the mix a bit more but what the heck let's give them the lifetime guarantee.:p

[jwholden]

Couldn't resist the photo op.

Do all landscapers look the same?:shocking:

[BJR]

Only the young ones.

As you get older you tend to block out more of the background.

With muscle of course.

And I must say that is a huge tool (mixer) you have.

[Stonehenge]

Looks like they've got a bit of a drainage problem, judging by the grade outside of the stones you're installing, and what looks like rotted wood on the house. If that's the case, you may want to consider some 3" perf/corr pipe in front of that wall to take the water away, if in fact they have a water problem.

You look like you have an honest face - gotta watch out for those guys!!

[jwholden]

I installed the belgian block to keep the dirt back from the house. It was literally covering the siding!

The block is there to keep any future mulch/topsoil off of the house and will have some peagravel behind it. I'm not concerned about water running toward the house, just soil/mulch touching it.

Funny, but I can throw my khacki dickies on and look like that stonehenge guy and many of my local contemporaries. It seems to be the look!

[Tim]

:geek: If you do install drain tile near a buildings foundation, I suggest using the cloth sleeved type. It doesn't clog up near as quickly as the regular corrugated tile. One other product that may really work well for your wall bases is called Perma-Drain. If you are not familiar with it; it is basically a hollow, plastic 2" by 4"(comes in different sizes) that has small slots in it. It's normally used to form building footings. It's real fast and easy to install it level, and it's a superior drainage system. It can also be set to allow flowage between in and outside runs of tile. :cool2: Neat stuff and a huge time saver, but not cheap! Tim

[jwholden]

Tim,

I notice your a former concrete man. Seeing as your in the post about mixing portland cement any tips or tricks to mixing that stuff. Times when maybe you would make the ratio of cement to sand lighter or heavier, tricks for curing, best base prep., recommended pitches, etc. Always looking for knowledge...

Thanks,

John

[Tim]

Yes John I am. I tryed to post a lengthy reply here twice las night to answer, but each time I finnished it, the system said I wasn't logged on, so I am going to break it up on postings one after another. Sorry it took so long to get back to you. Mixing: My father taught me to 1. gt my bucket or tub wet 2. pour in my sand 3. mix the sand till evenly wet w/ 1/2 of the water I planned to use 4. add in portland and water and mix together till it looked like my mom's meat loaf! :x

[Tim]

On curing: If it is Summer we use several methods. Most common is to cover the application about 2 hrs after it is completed with damp burlap. We try to keep the burlap damp for 3-5 days. According to the seminar I took at the World of Concrete trade show, if you cover your application sooner than that, you can actually send your work into shock, which may end up causing early deteriation. Another way is to spray clear sealer on the work(usually not vertical stuff for us) right after it is completed. Normally, we use TK Bright, or Mystic(blue can) to do this with. On our road and comercial stuff, we always use the DOT approved sealers(white and very thick) that you would normally see on the interstates. In winter, we try to cover the work as soon as possible with heat retention mats, I prefer the old, heavy canvas type over the new styles. The old ones don't blow away as easy. If we can't do that for some reason, then we cover or work with a minimum of 4 inches of straw. We leave the work covered for a week in both cases. :bag:

[Tim]

On base prep. If we were planning to work over existing slabs, we normally try to power wash the contact surfaces until they are clean. If we could not do this, then we use nylon brushes and water to remove any dirt and/or loose material. If we needed serious bonding capabilities, we use a etching type compound or scarifier. Nasty stuff to work with. If you are refferring to sub-grade prep. I personally prefer to use inch down, white crushed/chipped rock that is plate compacted over dry clay as my primary sub base. Yellow limestone in the same size would be my second choice. For a finnish grade, I prefer either white, or yellow lime screens, struck off to height and plate compacted twice for perfect elevations. I avoid sand as much as possible. Like you, I do like to use pea gravel for tile bases. Though I think it is the best to use for drainage, it is pretty mobile and hard to get any decent compaction with it.

[Tim]

On mixing again(forgot to mention using with a motorized mixer)

We normally sub our wall work to a very good block mason. He is a one man show, and would always require a laborer for our apps. He taught me to do the same order as I used mixing by hand, but he had me use 3 heaping shovels of sand, to one level shovel of portland. He was a real stickler about using a coffee can to pour the water in, and not the hose. I would start with 6 sand 2 portland sized batches. If I got it too wet, I could correct it by going up another 3/1 shovels to dry it out. I always had to spray out the mixer completely after each batch. I also learned the hard way to never call a block layer, a brick layer ever!! :blowup:

[Tim]

Whew! last one John!. Glad I did it this way, this is all the stuff I lost twice last night!:censored:

On pitches: I am not sure if this term means the same as slump- this is measured in inches. The amount a cylynder of concrete or mortar placed upside down will drop inches from it's original height is your slump rate. I prefer to work with a 3 to 4 inch slump for the best strengh to workability ratio. Usually the less water your cement or portland has in it, the less shrinkage and bleeding you will have, and the stronger the finnished product becomes during break tests. The guys tend to grumle a little because it is a little stiffer to use than they like, and they have less time to work with it. But time is money, and customers want quality for their money. Hope some of this is what you were looking for John. Tim :cigar:

[jwholden]

Tim,

Thanks for all the great info. Most of the masons around here prefer I hire them instead of divulging info. I love to pick up little tricks here and there. I like the 3 heaping sand to 1 level shovel of cement idea.

I know I read somewhere that concrete that is mixed drier is stronger, maybe the paver literature because they bareley wet their concrete. I told my guy to mix the batch until it started forming balls in the mixer for my belgian block work.

I'll keep you posted on how I make out with the Accuscreed on my next walk. I'm starting Tuesday.

Thanks,

John

[Tim]

I am always happy to help in anyway I can. I know how tight mouthed people can be from the professional crappie circuit. It can really suck when you are frustrated. I am looking forward to your comments on AccuScreed. I really hope it is the answer for your needs. Tim