# Forum Home Renovation Concreting  Concrete footing for cantilever umbrella

## scottb721

I want to place a couple of bags of concrete in our poolside garden and create an anchor point for a cantilever umbrella. Plan is to dynabolt it down using existing holes in a plate on the pols base. Normally this bolts to a large X umbrella base. 
Can I use quick set for this ? 
Any other tips ? 
Thanks

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## Bloss

You could use quickset, but why? Regular is cheaper and stronger. Main issue will be to get depth - the leverage potential of an umbrella is high - so narrow and deep is the go with sides vertical or even flared out at the base a little - not into a point or with rounded corners at the bottom. Probably min 600 - depends on soil type - soft loamy or sandy go deeper hard clay maybe not so much - but 500 600mm I'd reckon. 
Use the metal base a template with the regular gal bolts hanging free into the concrete or mark the hole positions onto a suitable piece of ply or mdf and position over the footing when you've poured the concrete rather than pouring then drilling for fixing.  :2thumbsup:

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## scottb721

What do you mean by bolts hanging free into the concrete? 
Fixing bolts into the wet footing with the threads upwards? 
Thanks

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## Bloss

> What do you mean by bolts hanging free into the concrete? 
> Fixing bolts into the wet footing with the threads upwards? 
> Thanks

  Yep. Very common practice - create an accurate template using ply or lengths of timber or chipboard, masonite or even heavy cardboard (using only once so doesn't matter). Work out how to place the template over the hole so that the bolts will be in the correct position. The bolts (or threaded rod) are passed through the holes with the heads down into where the concrete will be and the nuts screwed on so sufficient thread remains above the template and concrete to fasten whatever it is you need to fasten. 
Bolts/ rod need to be long enough to give good purchase in the concrete block - not much point having a big block of concrete if the bolts can pull out! Often the bolts/rod are bent a little at the bottom so they provide more resistance, or have a cross piece of reo or other steel welded on, but that's not necessary. 
You need to be sure you can place and remove and replace the template with bolts accurately so that you can set up, remove the template pour the concrete replace the template and push/ wiggle the bolts down to the correct depth. Then just leave until the concrete sets, remove the bolts and the template.  
You should be left with threaded steel mounts exposed that your item can sit over and be bolted onto easily. If you ever need to remove then simply unbolt. Permanent removal can be simply grind off the bolts or remove the whole footing. Bolt/ rod nuts, washers etc should be hot galvanised. There are special bolts called J-bolts for this purposes, but not needed for this small job. The pic attached shows a template for a round pier/ footing and this  pic shows a commercial template for the same purpose - you could use the umbrella base as the template as I said above.  http://bolttemplate.com/images/BT0009.jpg  :2thumbsup:

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## scottb721

Thanks for the informative reply Bloss and the time taken. 
I was originally going to have the bolts screwing into the concrete but might go with your idea of the thread sticking out.

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