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Portland or mortar cement

motoj550

Rock Crawler
Joined
Sep 25, 2011
Messages
520
Location
Stanford
I'm building my own course and am wondering which to use portland or mortar, i've tried the mortar mixed 4 to 1 ratio with all purpose sand and i just seems to gritty, should i be using portland instead. Any help would be appriciated.
 
Portland is good for outdoors its whats used to make concrete.Mortar mix is used for brick & block laying.
 
just did a little more reading and found out that mortar is a mix of portland and sand and lime, so mixing with even more sand was really making it gritty and loose, very slippery, think maybe mixing sand with portland will do the job. also i had a little peice of a mini course we did a year ago that was made with just straight cement mix and that had good traction also.
 
Also regular Portland has small gravel in it.

That's not my understanding. Portland cement is a fine powder and mixed with water becomes the glue for concrete and mortar. Mortar gets a little sand mixed in, concrete gets both sand and gravel.

OP, go visit Home Depot and ask them about all their options. They'll have quik-crete, fence-set and other bagged products you can just mix with water. They all contain Portland cement and other stuff. But they're all more expensive per pound than buying ingredients in bulk and mixing your own. Pre-bagged is probably more practical for small quantities.
 
if you have the option, try to find "struct-o-lite" -- it's basically cement with perlite mixed in...makes light(er) weight concrete forms. our sculpture students use it all the time, it's good stuff.
 
I have use mortar on several occasions with great results. All the stuff I've made are outside all the time and they range from 2 years to 3 1/2 years old and are holding up very well. Just make sure you use wire lathe with the tar paper backing, this will reduce waste. I'll post up some pic's of what l've made for some examples. ;-)
 
Also regular Portland has small gravel in it.

Your idea of Portland cement is actually concrete. Concrete is actually what I do for a living. So cement is actually a binder that is a fine powder. When added with water binds products together in..... Stucco, concrete , mortar etc.

Cement straight is a weak product but when structural additives like sand and aggregate (rocks varing in size) will take more loads.... And makes it concrete. You can change amounts of Portland to make mixes stronger or weaker changing psi ratings.

This is my quick explination while I'm sitting on the pot on my phone......"thumbsup"
 
I was told and also been reading to go with a 4 to 1 ratio, i used mortar and man it just looks like darn near pure sand and has no traction whatsoever and the sand just keeps flaking off. is it because i should have used portland instead of mortar because mortar already has sand in it.
 
Here are some pic's of what I have built with mortar. There is plenty of traction as long as you don't smooth it out with a trowel.

This is the under side, as you can see, you can't put a lot of weight on it. A 6lb rig doesn't do any damage.
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Here are some other things I've built.
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This should give you an idea how to use mortar when building a man made course. Hope this helps."thumbsup"
 
Looks good stelerzman, kinda doing the same thing too, here's a few pics of my rebuilding my course. just need to use portland mixed with sand next time to get better traction, the mortar mixed with sand was way too sandy (looked like it was just wet sand when mixed), no traction.
 

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WOW, very cool. "thumbsup"
I can see that you smoothed it out a bit too much. Maybe try to wet down what you have then add more mortar to roughen it up. Look back at my pic's and see if you find were I used an old set of pl hammers to to add traction.:mrgreen:
 
... just need to use portland mixed with sand next time to get better traction, the mortar mixed with sand was way too sandy (looked like it was just wet sand when mixed), no traction.

Yeah, too much sand because you added sand to a sand product. I wonder what would happen if you sprinkled a little straight portland on top of what you have now. Maybe you could "glue" down the extra sand on the surface.

Good looking project, tho.
 
How well would it work to mix in medium to large sized gravel into the mix? I haven't seen it done but it would seem like it would add a nice crawling surface...
 
Are you implying something like regular concrete mix for making small slabs and footers?
The only problem is that there needs to be something to bond it to like rebar. I have tried to make small forms and just fill them but the strength is not there. In most cases the piece will fall apart. I have had some success with mixing in some bonding agent to the quick setting post concrete, the stuff you just dump into the post hole and add water then let set up.
For me, mortar is the way to go.8)
 
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