It looks like you're new here. If you want to get involved, click one of these buttons!
...... 1-1/2" hole saw for a 1-1/2" o.s. dia. tube .
As you said already , you are in control of the pressure . One suggestion , cut in from both sides . Don't cut clean through from just one side cause blow out may happen .
Another way to help prevent blow out if cutting through from just one side is to ... use a backer up tight against the side , something like a piece of 2x6 held tight either by hand (someone elses) , or preferably clamped .
Also some hole saws have finer teeth than others , finer is better for your job .
I wouldn't use a larger saw than the tube . If the fit is really snug try a fine rat tail to ease it a bit .
I wouldn't cut too close to an edge cause I think there's a chance that a crack over the hole could develop in time .
ps., ... a variable speed drill would be best cause you can keep the rpm lower and be more precision on thin materials that way .