wrote:
>On Wednesday, July 6, 2016 at 7:58:00 PM UTC-10, John Kuthe wrote:
>> On Wednesday, July 6, 2016 at 5:56:05 PM UTC-5, dsi1 wrote:
>> > On Wednesday, July 6, 2016 at 4:55:26 AM UTC-10, Janet B wrote:
>> > > My food processor and Ninja blades are getting dull. Is there a way
>> > > to sharpen them or must I buy new blades?
>> > > Janet US
>> >
>> > I'd just try sharpening the blades with a Dremel motor tool. How hard could it be?
>>
>> What Sheldon said about removing too much material!
>>
>> John Kuthe...
>
>I'd use a silicon carbide rubber point - that would probably work dandy.
Actually that's about the worst way to dress a blade, you'll only make
it worse, you'd end up with a blade all wavey and gauged... if too
cheap to buy a file use the fine side of an emery board, even the
small nail file on a nail clipper would work and use it as draw
filing, not cross filing, and cut into the edge, not away from the
edge or you'll create a burr that will fold over making the edge
duller than when you began. Remember, files cut in one direction
only, lift the file on the back stroke or it's all for nought and
you'll destroy the file... same with a saw blade. Unless you're a
very skilled/accomplished craftsman do not use any power equipment on
cutting edges. The highest skilled metal fabricators would always
choose the method(s) of least risk to accomplish the goal. There
would never be any reason to use a power tool for dressing one or two
edges, power tools are reserved for mass production whereas one can
afford to risk losing a small percentage of parts for achieving the
benefit of achieving greater production. In this instance one or two
parts are involved, so I would strongly recommend using only hand
tools. I happen to be highly qualified in the use of all machine
tools yet with my own personal applications wherever possible I always
choose hand tools with cutting edges. I own a professional bench
grinder but still I hand file my lawn mower blades, and I hand dress
them often rather than allowing them to become so dull as to require
machine grinding... it's actually easier and much quicker than
removing the blades for grinding and than to necessitate removing
large amounts of metal thereby greatly reducing the life of the
blades. In case anyone doesn't know rotary mower blades are only
flame hardened for a small depth of their cutting edge, perhaps no
more than 3/8", then it's soft parent metal... this to reduce
shattering from metal fatigue. So anyone who uses a rotary mower it
behoves to replace blades after about 100 hours of use, before one has
a terrible accident, the mower user probably won't be struck when a
blade shatters but someone nearby coucd be seriously hurt or killed as
though struck with a large caliber bullet... shattered mower blades
have gone through walls. Rotary mower blades typically shatter at
their weakest point, where the center bolt goes through.