When using a small arbor with your hole saw, one that doesn't have dual pins & a locknut, I have found that by wrapping a piece of solid copper wire around the base of the threads allows a gap between the arbor & the hole saw bit. This stops steel to steel connection and makes removing the bit easier.

 

   

I use a plastic or nylon washer the same as you use the copper.

Is that a Mac Tool brand hole saw. Only one that is red that I know of...or if its old enough a Mac Allied tool brand, which split up with Mac and is now Matco .

Looks like a Morse to me. 

Good tip, never used wire but do use copper washers. 

 

And people wonder why I keep all those copper washers from work in a nice laid out box at home. 

Good tips, all around.  All of my hole saws have pins, must have been an upgrade in the last xxx years

20 minutes ago, Cal said:

Good tips, all around.  All of my hole saws have pins, must have been an upgrade in the last xxx years

With the Morse ones I've got the smaller ones use an arbor like the one Bob posted.

Once they get to a certain size they have the two pins.

42 minutes ago, Larry Buskirk said:

With the Morse ones I've got the smaller ones use an arbor like the one Bob posted.

Once they get to a certain size they have the two pins.

I keep a few of the common sizes ready to go.

 

Red stain is SAE, Blue is metric stuff.

 

Morse arbor is correct. This is convenient when drilling a lot of holes in wood, just remove the bit and insert a short dowel in the thread side and tap the plug until it pops out.

 They do make an adapter to fit hole saws with the larger threads.