[ATM] Hogging!!!

["Norm Prince" <norman.prince@verizon.net>]

...which meant something else all together many years ago in my college days.

Anyway...I spent the better part of the day scanning the WEB, and dutifully going thru the archives, while the rig i set up was working on the edge of that blank I trepanned after New Year.

(I screwed a 2x4 to the much unloved "mirror-o-matic", and then a hinge to that.  Added a little 1x and masonite housing for a grind stone to the flapping hinge, and hooked up a little rubber band spring <after centering the blank and epoxying on some blocks of course>.  Its slow going but it seems to be bringing the flaring problem to a tolerable minimum.)

What i really wanted to ask about though was subdiameter tool hogging.  I've selected three canidates for the 12" blank.  They are as follows: an almost 5" piece of plate steel (from god only knows what)...an almost 6" ring (outer housing of a big roller bearing), and a 4.5ish grind stone (granddads ole time axe grinder...just thought it might save me the grit???).  I would be so delighted to hear the range of opinions expressed about which is the best choice.  I posted a pic of the canidates along with a pic of the edge grinding set up at http://mysite.verizon.net/cmb15s7x/temp.htm

...but what i really need some input on is strokes for said sub-diam hogging.  Are these CoC?...tool on top or mirror???...and length of stroke is a bit of ??? too...almost to the edge?..how much is almost?  I've only made 8" mirror to date, and i used a full diameter tool; grinding almost exclusivly mirror on top...any input would be greatly appreciated.

Your humble novice,
-norm-
Georgia, USA (land of bad seeing)
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