Polishing questions

S

slideways

Joined
Jan 8, 2001
Messages
13
Okay a box of wheels and compounds etc. arrived from Jantz yesterday and I'm off and running at the bottom of the learning curve. I've read that many makers polish not with compounds and wheels but with sand paper. This is starting to make sense after some experimentation last night. The main problem I'm having is holding a blade in a way as to get good contact with the wheel. I'm also considering sanding to a near polished finish then going to the wheels. It is tough to get a consistant finish on something that starts out with visable grind lines and I'm thinking that sanding will remove those leaving a more uniform surface to start the polishing with the wheels. But again there's that holding the blade problem. My goal in all this is to learn a more about the art and craft of knife making and modify some of my production knives to make them uniquely mine. Any advice would be greatly appreciated.

Thanks A.J.
 
First advice: Be carefull, buffers are the most dangerous tools in the shop.
Always wear safety glasses and respirator.

For good results you have to sand your blades up to 600 or 1200 grit. Start with 100 grit, then 220, 360 or 400, 600, 800 1200. Work alternating lengthwise or crosswise, change the direction each time you go to a finer grit. So you can controll if there are any scratches from coarse grit left. With the finer grits (600, 800, 1200) you should only work lengthwise.
 
Thanks. The safty precautions are not lost on me I was a machinist for many years and it is always good to be reminded. I move the wheel outside when I polish so so the shop isn't turned into a mess.

I still would love to hear from someone with advice on how to hold the stinkin' blade. I was even considering super gluing it to a flat surface but with the heat the adhesive might not hold and then there would be glue clean up to deal with. Any help?
 
I finish by hand to 800-1200 grit and then buff if desired. Since I don't buff often I hold my knives by hand and go slow. I've seen makers who buff more use vise grips on the tang or bolt through a hole in the tang into a handle that backs up the blade. Remember that buffers are for buffing not finish sanding.
 
Yep, you'll never polish out grind lines. Get rid of the scratches on the grinder, then remove the haze on the buffer. I start with dark green compound on a hard (felt) buff then use Scratchless Pink compound on a loose buff to remove the last little bit of cloudiness.

As for holding the blade, you should be using the same size buffs as your grinding wheel, so what works on your grinder should work on your buffer, just remember to hold on tighter. What Armin said about the danger in using a buffer is not exagerated. I personally know several knifemakers who have had blades stuck in their foot, their leg and in one case their belly.

------------------
Jerry Hossom
www.hossom.com
The New Tom & Jerry Show
 
I've never been seriously injured by a buffer, but I've been smacked upside the head with little plastic bits by it. Once, I was re-finishing an old knife and the blade got caught in the wheel. I wasn't letting go for nothing, so my hands twirled around the wheel 10 or 15 times until I finally pulled the blade out. Scared the crap outta me.
 
Thanks again to all of you. I reworked the blade that had only seen the wheels and on top of that started out black. This time it was sanded with 320 then 600 using direction of stroke to highlight the scratchesof the previous grit. I finished with a loose wheel and white rouge. the result is mirror but I'm a perfectionist and I have a ways to go. As a first attempt on a daily user I'm okay with the results but it will be better next time. A couple of small areas although polished have a texture, probably fron the wheel the on the first try.

Does Cool Tool really help while sanding? Where can I get finer then 600 grit?

Thanks A.J.
 
AJ-

Cool Tool II cuts down on sanding time significanlty. If you are just doing some knives you bought and don't want to get too into this... WD-40 will work, as will Baby oil.

Many auto parts stores carry wet/dry that's up to 1200. Most home improvement stores have it too. If you can't find any at those places (I suggest them first for small quanitities) you can order it from places like Super-Grit, Econ Abrasives or Industrial Abrasives.

Good luck,
Nick
 
Be very careful with that loose buff it can be a killer. Loose buffs tend to wrap around objects and pull them from your hands.

I own and operate a metal polishing shop, with all my experience I refuse to use a loose buff on knives because of the danger. I prefer to use a circular sewn buff with 1/2" spacing between rows of stitching, the finish is just as good but the risk is greatly reduced.

------------------
george
www.tichbourneknives.com
sales@tichbourneknives.com


 
Remember to buff the bottom 2/3's only. Then turn the work over. Don't buff from the top of the work as that's when it takes it away from me and slings it around.
This is what I do, not the safest.
Roughly, Lynn
 
I guess it depends on what kind of grind lines you want to. I demand that my knives have sharp grind lines...which is more difficult than just washing over a blade to get a mirror finish.

Nick
 
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