Metal stepped hole reamers - just how accurate are they?

[rafezetter]

I have a large metal diamond slitting disk (not the stone style, more like the dremel ones) that I bought with the intention of using with my angle grinder fitted in a grinder cutting stand to make accurate cuts in some 25mm square ali bar, but failed to pay accurate attention to the grinders fitting mechanism and the slitting blades bore is too small by a few mm's.

I was going to buy one of those stepped hole reamers for metal, but I've never used one so I have no idea how good they are at self centering so that the central axis of the hole / disk remains the same, as obviously if it goes off by even a fraction the slitting disk will spin off centre, and that would be bad.

I have a drillpress so that makes using the reamer much easier.

Any and all suggestions / idea's / alternative methods welcomed.

 

[dejaa]

Hi
Actually they're pretty accurate, the cutting angle between the different diameters is shallow enough to guarantee concentricity.

Of course you should check that the cutter you're using won't then make the hole too big!

Personally i wouldn't use a diamond cutter for aluminium bar but a fine toothed HSS. You.MUST clamp the workpiece.

Hope this helps
David