To get back to my ramblings from yesterday, I have rooted high and low and come up with examples of what I was on about.
This pic shows a standard hand reamer with its tell tale square drive for use with a tap wrench. In the end of the square drive section is a centre drilling, to allow it to be supported centrally when used in a lathe or mill.
This one shows the three basic types of machine reamer, from left to right. A normal solid tungsten straight shank machine reamer, in the middle is a 1MT shanked HSS machine reamer and one the right is a tungsten tipped chucking reamer with no lead in taper, for getting square corners in the bottom of blind holes. Very little metal should be removed when using this last type, maybe 1 or 2 thou only, and is usually following a previously reamed hole.
This is how your reamers should be stored when not in use. If you haven't got the original protective materials, they should be mounted in a rack of some sort, to stop the sharp edges being damaged. If you throw them in a box together with no protection, you may as well make it the scrap bin, as they will soon dull to unusable.
This is what they will soon end up like if you don't look after them. These weren't mine, they were in the bottom of a box of tooling I bought.
The bottom one is an adjustable chucking reamer, if you look closely at the end you can just see an adjusting screw for opening up the flutes.
The top one should be in a rogues gallery for murdered tooling. This is supposed to be an adjustable hand reamer, but as you can see, one of the cutting blades is missing and it has been highly abused.
I personally don't like adjustable reamers, as unless they are kept in perfect tip top condition and spotlessly clean, good results are difficult to achieve. But I do suppose they fill a niche where non standard sizes can be cut at reasonable costs.
This is my set of morse taper reamers, one machine and two hand ones. The amount that they are used, doesn't justify buying a matching set, just ones I could get hold of at a reasonable price, at the time I needed them.
There are many other types of weird and wonderful reamers, but for what we do, these standard types are just fine.
John