Problem with mix for grout bag / grout gun

Finishing up my paver stone step project this weekend and ran into a horrible roadblock.

The Sakrete Type S stucco/mortar just doesnt' seem to be working as a grout. My choices seem to be runny mess and wet sand. Nothing close to peanut butter / toothpaste that all the videos show.

Any additive I can use (I've seen lime and plasticizer recommended)? Any other tricks I'm missing?

Thanks,
Anthony

 

I never used Type S with pavers. Type S cement if for foundations. We always laid pavers in a Portland & sand mix, usually a dry mix, 3 parts sand to 1 part Portland. A wet mix can be used for the edges. if needed. Then we would sweep fine sand, in between the pavers, at the end, of the job.

 

The Sakrete product already has lime in it, to enable its use to build up and hold vertically on the brick faces. You're mixing it with too much water.

 

If your problem is getting the grout to slip through the grout bag mix try mixing a little and I mean a little Dawn dishwashing detergent into the mix. To a bag of mortar put in about a half a cap full of detergent into the mixing water, let it suds a little then add the rest of the ingredients. This should slide through nicely. You can double the amount of detergent if necessary.

There are a lot of other things that will work but this is handy and easy to get. I suppose other brands might work. I only know what I have tried.

This is not a new invention. Masons have been adding detergent to slick up mortar for years.

Sometimes if the mixture is not rich enough it does not slip. Add a little more Portland to your mix. It will be harder and stronger and probably slip better. One or the other or both of these suggestions will help your mud go through the bag.

 

The rocks are too big in sacrecte for dawn to help, other than to keep them clean.

 

I've never used Sakrete's stucco/mortar mix, but if it's similar to any of the several others I have used, there are no rocks in it. Just Portland cement, fine and coarse sand, lime, possibly dye and a few other "trade secret" ingredients.

I think adding a wetting agent like Dawn dishwashing soap would be worth a try. Not much to lose.

 

Straight Portland with sand is the only thing I have ever used for pavers. It can be a wet or dry mix depending on the application.

 

Thanks for the replies guys.

I tried an additive to make it slicker (by the smell, I think it's just a detergent), didn't work.

Even though the bag I'm using had no big rocks, I think the sand is just too big. It really wants to stay a coarse clump rather than get nice and buttery. I've tried about 10 different mixes (dry to water to additive) and nothing works with the grout gun or bag. It just jambs up.

So I think I'm going to have to mix my own to get the consistency. Any advice on a recipe for just grout. This is outdoors on a sort of paver/stone veneer. I have overhangs and verticals, so some spots I have to have some thickness to hold up.

Specifically I'm looking for a grey grout, but an exact color match is not necessary. The stones have reds, blues, grays, and browns in them.

Thanks again -- I'll get this eventually.

Anthony

 

As I said, I only use Portland & fine sand, 3 sand to 1 Portland, for pavers.

 

Does that usually turn out brownish-gray? If so, that sounds perfect.

Obviously I need to get a really fine sand. Any cement, white portland, or is there something else?

Sadly I may be stuck with home center stuff (the sand and cement), since I want to try again tomorrow. The good stone centers around here are closed on weekends.

Thanks.

 

You'll probably get a gray color but it can be influenced by different factors. Here's a thread on it.

Why Does Concrete Cure White And Portland Cement Cure Grey? - Masonry - Contractor Talk

 

Well, I just tried the 3:1 mix with fine sand with the same results.

It just clumps and the water separates very easily. So when it looks like the right consistency, any pressure on the mix separates the water and the solids. I mixed with a drill for up to 5 minutes and tried several water levels to try and dial it in.

I then tried the flow-control admix with the same results.

I'm starting to think the cold might be affecting things. I will try again one more time with a small batch and hot water but this is maddening. Our outside temps were in the upper 50's today.

Ugh.

 

Upper 50s is fine for mixing Portland with sand. Are you sure that you are using straight Portland??? I never had that problem. We used to say, don't make meatballs & don't make soup. The consistency should be in between.

 

Yeah, straight portland and fine sand. Got it at our local stone supplier, not a big box store. Told them what I was doing and they said it was the right mix.

I brought some indoors to try with warm water. I'm also going to try hand mixing, in case my turbo mixer is not up to snuff either (flat plate with fins). I'm also going to use an egg timer for the slake as well, in case I'm cutting that too short (or long).

This is weird, I've done a ton of tile mortar and grout and never had this much trouble dialing in the mix.

Is the 3:1 by the scoop or by weight? Didn't think it was that critical, but I was doing it by scoop (volume).

Thanks for all the help.

 

It's done by volume [scoop] The weight of the sand can vary a lot depending if it's dry or damp.

 

I don't know why you're having such a problem. Yes, it is done by volume. We did it by the shovel full. 3 shovels of sand & 1 of Portland. It didn't have to be precise. We weren't mixing nitro glycerine.

 

I do computer/hardware troubleshooting for a living, so I tend to think about problems in terms of "what have you tried", "what changed", "what has been the same"?

The only common things here was that I was using this new turbo mixer that came with the grout gun and the temps have been cold (including the outside water).

I'm going to hand mix with warm water indoors (with the materials warm) and see if I can get a tile grout consistency (or close), even if I have to waste the batch. That should tell me what I'm up against.

It's frustrating to see so many videos of folks just squeezing the grout bag and having toothpaste squirt out with ease

But my first outdoor project, so I have to remind myself that I've never done this before, so expect the bumps and setbacks.

Thanks again guys. Good weather tomorrow, so I'll try again. It's not a big area, so once I get the mix down, I should be able to do the whole thing in two hours.

 

im would sugest try siftingg the sand portland i do this all the time with no problem the 3 ti 1 mix is good

 

I hope the original poster will tell us what he did that finally worked. I still think all he needed was some lubricant. I like a little lime in the mix or use masonry cement 2 1/2 sand to 1 cement.

If it is not too late maybe there is one other little mistake. Dry mix the sand and cement thoroughly before adding water. Mix it, let it slake a while and mix it again vigorously.

He should not have had that much trouble.

 

Hey guys,
Thanks for the follow-ups.

Sadly the weather caught up with me and it's not getting much above 50 here and freezing overnight every third day or so. Not a lot of time to work outside. We had a mini heat wave, but it rained the whole time too.

My next plan was to try a little lime. What amount do you all like? I was using 1:3 portland to sand. I also never got around to trying Dawn

Also, do you guys power mix or just trowel/hoe mix? I read that power mixing can sometimes whip too much air in and cause problems. This is tops on my list to take up as soon as we get a break in the weather.

Thanks again.

Anthony

 

A plaster or mortar mixer is preferred if you need large quantities of mortar and if you can use it quickly enough. There is certainly nothing wrong with mixing by hand with a hoe in a mortar box or wheelbarrow except it is harder work.

If you use the 1:3 Portland to sand mix then a half part of lime all by volume should slick it up enough to slide right through the grout bag. Less lime is fine if it lets the mortar slip through the bag. Or try the Dawn. And you can use the Dawn and lime too. Whatever works.
Or maybe if you can get it use plastic cement. The same ratios of sand and cement are fine. Plastic cement is formulated to pump through a plaster gun and should also slide through the grout bag. Dry mix, dry mix, dry mix, dry mix, then add water and mix and mix again and again if you are doing this by hand with a hoe.

 

Hi all,
Moderate success. Did 1:0.4:4.2 mix with hydrated lime. Early in the day when everything was clean, it flowed right out of the grout bag. Later when things got hot (and the tools and such had a couple batches through them) it started clogging a lot. Also, the last batch of sand I got from the stone center seemed a lot finer and consistent.

It's been slow going, but at least the grout is flowing.

Oh and the Cox grout gun seems to be worthless. Mixes that flow freely in a bag seem to just clog it. It squeezes the water out of the mix with the high pressure, then it's too dry to flow. I'm giving it one more shot with some dawn added to my mix, but for now I'm going to work on my Popeye forearms.

Thanks again guys.

Anthony

 

Follow-up with success!

The secret to using the grout gun is plasicizer. Sadly that stuff was hard to find, but eventually I discovered Gibco MRF. Don't know what it is, but it is recommended by similar grout guns, so I bought a tub for about $8. Just spent 8 hours grouting the stairs and it is a wonder.

Settled on a 3:0.5:1 mix (big number is sand, I always get that order wrong). 1 tbsp of the MRF for a little more than 1 gal of water premixed. Found a mix that worked well (water level) and used it +/- a little with each batch. The grout flows out of the gun like toothpaste. Easily flies behind the stones and such out of the tip.

Still have more to do, but I did the hard stuff today (risers, between stair treads, verticals). Still have the horizontal surfaces to do, but man was it easier with the plasticizer. Only downside is that I have to mix about 3 gun-fulls at a time, clean everything and re-mix. If I had a helper, we could probably keep it flowing constantly.

Thanks again for all the help. I'm hoping to have this done in two weeks, weather permitting. Pics when I'm done.

Anthony

 

Steps done, still need to do the walkway. Still need to do a deep cleaning and we had a light rain for about 5 minutes this morning (which is why the color is a bit splotchy in spots).

Was thinking about using Prosoco 600 masonry cleaner -- it's all I can find locally without bulk or special order. Then deciding on if/how/what to seal it.

Thanks again for the help all.