Using premix concrete bags, I put some water in first, then dump the bag of concrete in, and without fail I end up with clumps of half wet concrete stuck to the bottom of the mixer. I've got to get in there and scrape them off, and there's usually dry concrete mix underneath a wet layer. I've got to do this two or three times for every mix.
Is there anything I can spray on the inside of the mixer to stop this from happening? Lanolin maybe?
This. No coating will fix what you started wrong to begin with
Neverwet
Nitroglycerin?
Slow pour like you would a beer. And remember rushing projects only ends up costing you or the client, this time it was potentially wasted product, next time could be a structural support buckling, slow and smooth is fast.
Nothing wasted, it's just a PITA, and no client, it's all my own stuff. I just want to make it easier for me
You need some cement/ mortar plasticiser.
That's my fault thought this was a different sub lmao.
I put the water in, turn it on, then slowly add the mix so that it's dropping mostly into the water.
This, a super plasticizer should make all the difference and not wreck the w/c ratio
Hahahaha!
Lay bag flat, cut a slit in the center of the bag, width wise. Lift bag slightly from bottom on either side of slit. Bag should now be two little bags. Cut the connecting paper. Pour each half bag slowly into mixer. Should help. Plasticizer can help smooth the mix but shouldn't be needed unless the pour requires it. Also spray the mixer inside to keep the high sides wet. I usually leave a good bit of water out and add by spraying sides until I get the right mix.
In the trades you can use a light coat of form release or diesel and that will keep any concrete from sticking to the inside of the tank
You're using one of those small DIY mixers that holds like a few bags max, right?
You're doing it backward. Spray the sides to wet.
Add in the bag. Dry mix for about 30 seconds. This helps remove soft clumps. Hard ones, you won't get out. Then spray in water slowly until it is what you want.
Let mix like 2 minutes or so.
Mythbusters used C4 and it removed the problem.
I can't believe it's not butter
Havent used premix concrete bags before, but id assume do it much the same as mixing your own stuff. Wouldnt faff about trying to spray anything, personally.
Dont just dump it all in at once. Set it spinning, add some water, then add some of your mix. Let it mix in a bit before adding more mix and water.
I usually keep it fairly wet with the small mixers, only letting it get to your desired consistency near the end. Helps stop it sticking if its wetter while mixing. Make sure you can dry it up enough before full though.
The little mixers are bad for stuff sticking at the back though, no matter what. You can bash the drum with a hammer on the outside to dislodge it. Dont let the mixer owner see you though!
We use a piece of plywood on the ground. Drop bag on plywood, cut with a square shovel. Add to mixer one shovel full with water until desired consistency is achieved. I usually do 2.5 bags per load. That is about what I can fit in my wheelbarrow. Or you can order a truck that will bring it pre mixed. Anything over a pallet worth, I have a truck bring. Mixing 100 bags will take you all day.
Work it with the shovel
This is a thing.
I bet anything that the bag says pour in slowly, anytime I've worked with premix concrete I slowly added it to my water until it comes up to a consistency I like. Usually it's not the ratio of the bag says because of factors.
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Nightgaun7 t1_j12tuqa wrote
For starters, pour the concrete in slowly and allow it to mix evenly, not just dump it all in.