Hand mix concrete instead of postcrete

[curium]

Hi

I'm putting in some concrete fence posts. Some of the holes remaining from removing the existing posts are quite large but unfortunately need to be reused.

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I'm not sure bags of postcrete will be adequate so I'm considering hand mixing some concrete for the 2-3 posts that will be in existing holes.

My concern is how long the concrete will take before it effectively supports the concrete posts, allowing me to get on with fixing the next post. They're heavy so need support until the concrete gains sufficient strength.

I was considering using quickset concrete but am anxious as to whether the working time will be too short. I don't have a mixer so will be mixing the ballast and cement by hand before shovelling it in the hole.

Advice based on experience gratefully received.

Cheers

 

[pcaouolte]

If you mix the ballast and cement dry (don't add any water) shovel it in the hole an whack it down hard around the post with a sturdy bit of wood (do this in layers) it will support the post straight away. I have installed concrete posts in this way for 20 years, none have ever moved.

 

[curium]

If you mix the ballast and cement dry (don't add any water) shovel it in the hole an whack it down hard around the post with a sturdy bit of wood (do this in layers) it will support the post straight away. I have installed concrete posts in this way for 20 years, none have ever moved.

Cheers for this. Never occurred to me

Given the hot weather in the UK currently, should I pour some water into the hole first?

 

[pcaouolte]

No, you don't need any water in the hole. The ballast and cement mix will absorb water from the surrounding soil eventually but you don't need it to do that to make the post firm. Dig the hole a bit deeper than you need, shovel a small amount of ballast/cement mix in the hole. Stand the post in the hole and twist it into the ballast/cement with a drilling action until the top of the post is at the correct height. Get someone to hold the post upright while you back fill and whack down the ballast/cement mix a couple of shovels at a time. Keep checking that the post is upright as you go. Finish a few of inches below ground level. The post won't move if you whack the mix down properly.

 

[johnny2007]

As suggested, dry mix.
If you want after the post is in sprinkle a tiny amount of water in there and it will firm it almost immediately in this heat.

 

[mikeey84]

This is how I do it too.

If the ground looks a bit dry, I fill the holes the night before with water so the surrounding ground is damp enough, but there is usually enough moisture in the sand for the cement