Slitting saw questions

[SteveG]

I stumbled across these 175x2mm slitting saws today sitting on a high shelf where shorter folk had missed them. The one with the surface rust was sitting on top, but all 3 are sharp and in good condition. Price was right (free) so I grabbed them.
My mill has a slowest speed of 80 RPM so if I've done the calc correctly that should be about right to run these saws in mild steel. Would that seem correct?

   

I noticed that the drive cutouts in the center aren't exactly opposite. I assume that's so the saw can't be fitted on the arbor in reverse?
Since I don't have an arbor I looked online to see what they actually look like with a view to making one,  but can't seem to find any that have the same center style.

Can anyone throw some light on what they might be called?

Steve

[Mayhem]

With the right feed rate and lots of cutting oil, that should be fine. At just under 7", those are some pretty big blades.

Make up an arbour without a key. The friction of being clamped will be enough to drive the saw and it will slip if you get into trouble. With a key, it won't slip and you'll get big trouble!

HERE is a link to the one I made.

[SteveG]

Good idea about not having a key, and thanks for the link. Will make a nice little project.
I've also just had the thought that maybe I could just turn up some flanges and use one of the short horizontal arbors that came with the mill.

Steve

[awemawson]

Those look like 'cold saw blades' to me, of the type used on Pedrazolli type pull down cold saws, but they are a bit on the small size diameter wise - mine are 245 diam

[TomG]

They should run closer to 60 rpm, but as Darren pointed out, if you keep them drenched in cutting oil, they should survive. In my experience with large saws like that, it works best to plunge them to full depth before starting to feed them.

Tom

[SteveG]

Thanks Tom.
Just re-checked my RPM calc and realise I'd used 5" instead of 7" which explains my error. Not the first time a quick mental metric to imperial conversion has caught me out.

Regardless of whether they turn out to be useful, I've now got my first cutting tool for the mill !!

Steve

[randyc]

http://www.practicalmachinist.com/vb/gen...be-199969/