Circular saw blade mounting nut and flange?

[Dan K]

Folks, my twin blade mill build is progressing slowly, (No pics yet, only parts laying on the floor) and the time has come to have the verticle blade and arbor designed and built.
My question is : Would it be considered good practice to have the blade built with a pilot hole off centre from the mounting hole, to allow a pin to be incorporated into the backing flange? This would prevent any blade spin on the arbor, before the locking flange and nut are fitted. My apologies if this seems trivial, but this is my first attempt at such a project.

Regards

[Ron Wenrich]

Most circle saws have holes drilled for mounting purposes.  The large head saws have 2 holes for shear pins, and smaller saws often have 3 holes for mounting into collars.  It would be better than a friction type of mounting. 

[bandmiller2]

As suggested pins are a good idea.Without pins if you hang or bind the saw it will tighten the collar nut too much and may even spring the collars.Be sure to have the thread "hand" such as to tighten the collars insted of loosening. Frank C.

[Dan K]

Thanks for the info gents. I will let the blade maker know to build in 2 shear pin holes.
Frank, because I am designing the driveline from the blades back, the thread direction will should be correct   ;D

Regards