A couple of years back I bought a banana parasol in a hurry, as we had sun-sensitive visitors coming.
The feet are like this tinyurl.com/yr2ayaj3 (which I'd have said could do with being longer but they seem a fairly standard size).
I got plastic weights from a different source which look like this tinyurl.com/jku47smv. I filled one with sand I happened to have in the garage but it took so long that I filled the others with water. They feel similar weights to me, and are each pretty heavy.
The problem is that the opening for filling them is at the pointy end and thus mean that they don't sit properly in the feet, so I just sort of pile them up over it.
However we've had a couple of instances of a gust turning the whole thing over, which could be a bit dangerous if it fell on someone, so I need to improve it for this summer ( - should have thought of it over the winter I suppose :-) )
Any opinions on the best type of weights would be appreciated. I think the umbrella and stand itself is OK, and, as it needs to be movable as the sun moves, making a hole in the ground isn't the answer! :-)
Last edited by: smokie on Thu 19 Jun 25 at 12:06
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What was Heras temporary fencing is now tinyurl.com/2bhzex5e
Uses heavy concrete feet. You will have seen it around building sites.
8o)
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Thanks. Yes, hadn't thought if the fencing things but they seem to ne plastic or expensive. Unless maybe I visit a building site after dark... :-)
Biggle's suggestion looks good as I could sit that on top of my existing things which, now I've been out with the lump hammer, fit a little better - though I feel it still needs something else.
I did find some similar to what I have except they attach to each other, which if I can make them fit together close enough might keep them in place better. tinyurl.com/4vh7e24h
And my daughter has some sand bags (no sand) for an ugly brute force method :-)
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A parasol is basically a kite that you want to keep earthbound to provide shade.
The lift generated, as with any aerofoil, is proportionate to the square of the wind velocity. Thus a 10mph wind creates 4 times the lift of a 5mph wind. A gust of (say) 20mph will produce a force 16 times the 5mph wind.
Any wind will cause the parasol to move both horizontally and vertically depending on the shape of the aerofoil, its inclination, and depends on wind direction.
That a parasol will topple in a gust is a mixture of how much lift is created and horizontal pressure.
Making the base wider by extending the legs will help but I suspect the real solution is either lots of weight, or more radically - a few neatly cut holes in the parasol fabric to allow air pressure to equalise above and below, and reduce lift.
Bit like aircraft which can reduce lift with slats or spoilers disrupting the airflow over the wing.
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>> A parasol is basically a kite that you want to keep earthbound to provide shade.
>>
>> The lift generated, as with any aerofoil,
>> Bit like aircraft which can reduce lift with slats or spoilers disrupting the airflow over
>> the wing.
Except of course its not an aerofoil, wrong shape so maths is not based on lift coefficients. Its just an air bucket, its all about volume
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>> Except of course its not an aerofoil, wrong shape so maths is not based on
>> lift coefficients. Its just an air bucket, its all about volume
Aerofoils are usually designed to increase (aircraft wings) or reduce (car spoiler) lift. Making the design aerodynamically efficient is part of the design process. Strictly speaking a parasol may not be an aerofoil.
That the principal reason for a parasol is to create shade irrespective of aerodynamic efficiency does not distance it from basic physics. It is a an object which responds to the forces upon it (gravity, wind) just as a wing or sail.
This has been the subject of abstracts in the Journal of Physics which speculated on the wind speed required to get Mary Poppins airborne using the aerodynamic properties of the umbrella she always carried
journals.le.ac.uk/index.php/pst/article/download/2029/1932/3040
To avoid reading it the answer is a constant wind speed of 118mph with the umbrella held at at an inclination of 18.3 degrees or more!!
Last edited by: Terry on Fri 20 Jun 25 at 10:48
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>> the answer is a constant wind speed of 118mph with the umbrella held at at an inclination of 18.3 degrees or more!!
Did they take her voluminous skirts into account? Back to the drawing board.
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The answer of course, is a pergola.
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How would you move that around though? :-) I'm mostly trying to provide some shade for one of those large American style mosaic tile and iron (i.e. heavy and pretty immobile) Costco garden tables with the oversize chairs (which it can't completely) which is, I think, more than 2m long and over 1m wide. And we like the sun but we have visitor who don't. So a permanent fixture wouldn't work.*
I've ordered the Biggles solution - as it's Amazon it can easily go back but it looks like an easy and cheap solution to a minor inconvenience.
FC's fence bits seem to be mainly rubber online but it reminded me that there is a nearby place which sells concrete fence posts and similar so they may be worth a visit to see if they have anything suitable if we still have a problem.
* Could probably get a blind thing attached to the house and open it out when required but the table isn't quite close enough to the house at the moment, and we like it where it is.
Last edited by: smokie on Thu 19 Jun 25 at 16:18
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You dont move it around, its big enough (4 x 4) for your furniture, and the pillock who likes the sun you give them a deckchair on the lawn.
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images.dunelm.com/30927256.jpg?$standardplayerdefault$&img404=noimagedefault
These are better than deck chairs…bought one for €30 from China shop and taking it back to the uk. With a few bottles of Larios @ €11 litre.
And keep your disparaging remarks about Larios under your pergola:-)
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Yeah I have a few of them. Also some high back camping-style chairs which weren't especially cheap but well worth the money.
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I went for the Biggles solution, thanks, good find.
It was needed ideally for today, and having ordered on Thursday on Amazon Prime for next day delivery it should have been here yesterday.
However they entrusted it to Royal Mail who failed yesterday and tracking said arrival on Monday, then later Tuesday.
So I got onto Amazon customer chat to tell them they oughtn't depend on RM for next day and they kindly and unexpectedly gave me a £10 gift token, as well as saying my complaint would be escalated and I would receive a response in the fullness of time.
Shortly after putting the phone down the parcel was delivered! I won't be sending back the tenner as it'll pay for the sand to fill the (now) £4 sandbag :-)
I happened to have one pre Covid (= cheaper than now!) bag in the garage which has probably over half filled it, and the brolly has been up for a few hours now and despite a few moderate gusts remains stable.
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Cantilever parasol bases - neiltoo
