Petition Tax Free Overtime

As a working person for a small business and in the current economic climate I tend to work alot of overtime to bring in extra money only to find that I have been crucified by tax. After a 45 hour week the fact that I choose to do more hours to benefit me, only to lose a large percentage. Should we not be encouraging people like me willing to do the extra hours therefore generating more income also more disposable income to spend that can benefit the weak economy by removing tax on overtime hours. I feel the government should be looking for ways to help people not penalising them for working harder. If the extra hours tax were not worked they would not get this, we should have tax free overtime.