chamber 18 advanced H.E.L.P.!

[Goth_Lady1987]

I'm at the part in chamber 18 where the "danger ball" and turrets are, but no 'danger ball' to knock the off their platforms. Watched a walkthrough of what you're supposed to do: portal up to the protruding ledge closest to the entrance, then make a portal at the floor and another behind whatever platform. Fling into the turret to knock one down, then hop to each other one and so forth. HOWEVER, once I make said fling and leap to knock a turret off, the others pulverize me into Swiss cheese!
Is there a way around these accursed things, or is it inevitable?

Thanks!

[TheSovietXman]

This may not be a good answer, but maybe try another newer video?

[SenutnaKG]

a

[CSharpCoder]

You just have to do them in the correct order. Find one that the others can't see and do it first.