On 19/02/2019 16:39, John Rumm wrote:
On 19/02/2019 16:10, Jim K.. wrote:
I need to lift a huge yorkstone flag, approx 4ft by 4 ft by 4 inch
Â* thick, by about 2 inches, & rebed on mortar etc as
Â* necessary.

That's going to be something like 350kg if its a uniform 4" thick!

I can dig under the front edge if necessary, the sides are flower
Â* beds so digging is limited & the rear edge is tight against the
Â* house.

Any suggestions on how to approach?

Sounds like you will need to lever it up from the front edge (propping
as you go) until you can get it on end, so you can relay the supporting
screed.

To relay it, treat it like you would a large shower tray. Slap a couple
of runners into the screed so the tops stand proud of the wet mortar.
Say a couple of lengths of 40mm waste pipe running front to back. Get
and end of the slab on the runners, and then slide it into position.
Then pull the runners out to drop it onto the mortar bed. You may need
someone on a long level to take the weight off the edge to get the
runner out.



If I've found the right density and done the sums right[1] it's around
360kg. I can see 40mm uPVC taking that when spread evenly over the 2
lengths but wondered about when the slab is only partly on. Fill the
pipes first?

[1] 0.15 cu m at 2400 kg/cu m

--
Robin
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