I asked on Reddit, got no real answers.

My plate collection is a pretty rag tag bunch of low end and used stuff.

I have two very close to normal sized 45's, everything else is smaller in diameter.

So if I am deadlifting and I load the two regular 45's first, then everything else needed to get up to working weight, will the two inside plates being the only ones that touch the ground harm the bar at all over time?

I don't drop it or anything, but it's a pretty rapid descent from below the knee. I have a single layer of stall mat down, I might pick up some more today and try to cushion the floor a bit more.

I just don't want to bend the ends of the bar or damage the collars and bushings any more than regular wear and tear. I'll pony up and start buying bumpers this winter if it means my equipment gives me more service life.

I wouldn't worry about it. If I bent my bar, I'd tell everyone I know that I lifted so much weight that the bar yelled, "Uncle!" Then I'd by a new blemished bar from Rogue.

What kind of bar is it?

Bending is unlikely, but it's possible to damage the collars.  Bang enough deadlifts off the floor (or drop) and your smaller plates could start to scar the collars, if the bar is cheap enough, maybe even really damage.

Texas Power Bar.

I try to be gentle with it, but my wife the other day asked if I was "Getting shelled by artillery downstairs"

I'm going to pick up thicker mats today.

I do the same thing but my bar is a cheap piece of crap anyway. If i manage to break it i have an excuse to buy a nice one.

Pretty difficult to bend a collar.

I wouldn't give it a second thought.

Thanks.

I guess if I mangle it somehow over time I'll know better next time.

I did double up my mats today, I had to do it anyway because I cut it wrong last time and put seams in stupid spots, and because my big plates only measure 17" exactly I cut some squares to pull from (two 1/4" thick pieces should get me pretty close to standard height)

So now when the bar lands it will be hitting 1" of rubber total, hopefully saving absorbing enough shock to save a little wear and tear on stuff at least.

Preliminary "drop heavy stuff from up high" testing shows way less noise and floor vibration.