How much of a weight difference when using a Smith machie versus using a standard bench for bench pressing or any other routine?
Say what? I will offer an answer to what I think your asking though it will probably be as vague as your question
It really depends. There is no standard formula.
This is the true joy in life, the being used for a purpose recognized by yourself as a mighty one; the being thoroughly worn out before you are thrown on the scrap heap; the being a force of Nature instead of a feverish selfish little clod of ailments and grievances complaining that the world will not devote itself to making you happy - George Bernard Shaw
I think I know what you are referring to. The bar on a smith machine generally carries between 10-15 lbs of resistance whereas a standard olympic bar weighs 45 lbs. This means that if you had a 25 lbs plate on each side of a smith machine you are talking about 60-65 lbs as opposed to 95 lbs on a regular barbell.
Check out the website of the company who makes the smith machine that you are using for the exact weight.
Hope this helps...