grinding the flats

J

jasperdog1

Joined
Dec 20, 2005
Messages
29
Alright, I've just hollow ground two blades. best I could with a 36 grit then a 150. They looked pretty good until I got to the 150. I just can't seem to get the waves out though. Anyway, do you just hold on for dear life and lay the whole blade on some type of flat sander. I was read to sand the flats down to 400 grit. Just a little worried on how to hold on to the blade and sit it down and pick it back up without nicking the grind?

Hope this makes sense, I'm not the best at explaining :rolleyes:

Dave
 
To gring the flats hold the knife vertical,in other words opposite of the way you ground the bevels.You also need to do this on your platen not the wheel.
 
it might be helpful if you were more specific on what you are trying to do. sometimes pictures can explain things better.
 
It would help if we knew what kind of knife your working on.for small folder blades,i drill pivot hole/holes through piece of 1/4" micarta..,use brass rod to hold blade flat against it,then press against platen.saves your fingers and offers more controle!
 
If your grind lines are wavy, you need to fix those on the wheel before you sand the flats. Uneven grind lines will just become crisp uneven grind lines when you sand the flats.

If you're flats are actually the part that's uneven then you can carefully hit the flats with the platen (if you tilt the blade you'll probably have to do another pass on the wheel, no biggie) then switch to a piece of glass or other flat surface and sandpaper. If you take a strip of masking tape about 2" long, pinch it the middle and stick it to your blade you'll have a little tab to grab onto while sanding the flats. Pull in one direction on your final grit.

You can also use a disc grinder for your flats and probably save a lot of time on the platen and glass plate.

P.S. The tape is only for hand sanding, not sanding on the platen.
 
If I want a flat to be really crisp I hand lap it on my DMT sharpening stones I start with the black (extra coarse) to refine and shape after the belt grinder, and work down to the green (too fine to feel the grit, meant for finishing a "razor edge") at that point it is fine enough that I can finish it on a jewelers split lap with platinum compounds

-Page
 
If I am hollow grinding a blade, I take the flats down to about 240 grit prior to starting a hollow. Then with the flats nice and true, it is easier to get a nice even hollow ground out. It is very easy to mess up your grind line on your bevel when hitting the flats afterwards.
 
Thanks guys. Sorry about not explaining wel. Ever since my accident I know what I want to say, but have problems putting it down......makes me feel like kid sometimes.

I'll try what yu sugested. I guess my grindin problem is at the tip of the blade. I'm using a rest, but evey time I get to the tip I seem to change the ngle. RRRRRRRR! Thout I had it figured out. Guess it is back to Lows for more practce steel.

Thanks agin,
Dave
 
You must log in or register to reply here.
Back
Top