Filling deep holes

I have a lot of deep holes which I have been filling with decorators lightweight filler, I am having extreme difficulty getting the final layer to be perfectly smooth, and ideas?

my searching of this site tells me to get gyproc easy fill???? from b&q mix it, apply it and sand it. Will this give me a smooth finish, I have a sander that looks like this:



would that improve the smoothness rather than using my hand to sand?



What is the best way to apply filler?



thanks everybody who helps

Im not keen on the lightweight stuff..it takes an absolute age to dry really hard...

And despite what they say...can shrink.

Personally i find its bette to build normal filler up in several layers

However, all this doesnt help your problem..you could overfil it with normal polyfilla, make sure you use a tool thats wifer than the hole itself by a couple of inches...that way youll be able to feather the edges off when you sand them..

Dont pile too much on...again like filling deep holes its far better to put a couple of thin layers on than one thick one.

Use 100 grade abrasive paper to rub down...wrapped around a sanding block.

hi, went to b&q , and i got ready mixed plaster. I used it to make the final layer perfectly smooth and the layers behind were the lightweight stuff. thanks for the help