Smaller Diameter Plates a Problem?

My nephew has offered me some plates he purchased a while back at a big-box sporting goods store. According to online sources, this brand of 45 lb plates is about 2" smaller in diameter than proper 45s, Obviously a potential problem for deadlifts. My plan is to buy a couple pairs of correct diameter 45s and put those on the bar first to get the bar at the correct height, then add the smaller plates as needed. Will I be risking damaging anything (equipment wise) by doing this? IOW, when my deadlift gets to 405, am I risking damaging my bar if only four of the eight plates are making contact with the floor? For the record, I'm not one of those guys who drops the last rep of a deadlift from the top of the lift, so while the last rep may come down a little faster than the earlier ones I still maintain control of the bar until it's on the floor.

Or, is a one inch deficit on the deadlift really a big deal? I have no aspirations toward competing, I'm just trying to live longer and stay capable for as long as possible.

Thanks in advance!

One inch is a big difference. Lots of people will have trouble just getting into position from it.

You can easily correct this with a little bit of plywood or rubber under the plates if you're just using those ones as the largest in the set.

I've been using a big box store set of plates like that, and it works fine to do what you already thought about - just get some correct diameter plates to put on first. I just got a set of 45 lb bumpers and 25 lb bumpers and load those before anything else. Works great, and no problems.