brown upvc window frames

[stayclean]

called out today to look at some upvc windows frames which had paint over them , products ive used on white upvc were no good due to wood grain pattern in brown upvc , has anybody got any ideas how paint can be be removed
any help would be apperiated

 

[masona]

Very tricky, I've just taken out a upvc door frame to be sent away to change the colour of the door frame from brown to white, I don't know how they do it but told me they heat a thin film over it