Machines - question about them

Last week I had to workout in a different gym from the one in which I usually workout.  The machines were a different brand but otherwise seemed to me to be pretty much the same.  What I found odd was that the weights I normally use didn't seem to transfer over.  This doesn't make much sense to me and I honestly don't think that I was more tired or anything.  Anyone have any insight into this?

Very normal Pam. Different brands will vary in regards to the actual resistance (aside from the weight you lock in) that the actual machine provides. You didn't get weaker! :) I can't lift as much on the machines here at the diet doc as I could at home on some, but more on others! The ergonomics of the machines will make a difference too!

Actually, when talking about pullies the biggest mechanical advantage comes when multiple pulley wheels of different diameters is used.  Additionally if the pulley wheel moves with the cable as opposed to being fixed you will get more of a mechanical advantage, but you are right doc, number of wheels matters too.  as does thickness of the cable and a myriad of other things like if cams are being utilized instead of pullies...basically...it is not a fair comparision to try and match machines of different designs and makes together.

I knew our resident physicist would jump in on that one. LOL.

Thanks all!  :) :)

Man, I forgot all about Jordan on issues like this...you need to go get a quick degree in biomechanics, Chabinsky - you'll love it.  I remember a professor putting together a model showing the physics of muscles in the jaw (for TMJ problems) displaying how low back postural muscles change the biomechanics of the thoracic and cervical spine, thus cranial position, this muscular tension in the face, etc - all with strings, small weights, and pulleys on a model.