Author Topic: Pier build  (Read 1344 times)

Longjohn54

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Pier build
« on: October 20, 2015, 02:49:09 PM »
Today my back is sulking.  It won't bend and worse still when it does it won't straighten up again.  Pain killers make little difference.  Wonder what I did to cause that?  :-\

Yesterday I mixed 800Kg of concrete.  By hand.  Chucked it in a hole.  By hand.  Hmm! I think I have the answer.  :)

According to the internet the best water to cement ratio by weight is 40% with a maximum of 55% before it loses strength.   Readymix is generally 40-45% so that seems good enough.   I started by weighing 5Kg of cement into a bucket then I marked the fill level in the bucket for repeatability.   As for water, I filled a 2 litre plastic drink bottle.   The ballast comes in 25Kg bags which were pretty damp from sitting in the garden being rained on for a few weeks.  So I'd end up with a 5:1 mix plus 2Kg of water making 32Kg of concrete.

The process was to pour 1.5 litres of water into the bucket and add the 5 Kg of cement.   Give it a wizz with the drill until it was thoroughly mixed into a wet paste then add the 25Kg of ballast.   Mix and add water as required until it looked right.   Usually the remaining .5 litres of water was enough but an extra cup full helped.

As long as I stood upright mixing was easy.  I could have done that all day.   The 750W drill was set to the slowest speed (too fast made a hole in the middle and didn't mix anything).   Lifting and pouring the ballast into the bucket was much harder than I thought it would be.
Walking to the garden tap to refill the bottle was good to relax the muscles between mixes.

By far the best bit was pushing in the mounting rods.   I had polar aligned the mount previously and marked the alignment so it was simple to get this accurate.
John

Ad Astra Tabernamque  (to the stars and pub)

gary1968

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Re: Pier build
« Reply #1 on: October 20, 2015, 04:10:00 PM »
Looking good John, I'm sure that the pain will be worth it.

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