Jump to content
  • Announcements

    • Alan Longmire

      IMPORTANT Registration rules   02/12/2017

      Use your real name or you will NOT get in.  No aliases or nicknames, no numerals in your name. Do not use the words knives, blades, swords, forge, smith (unless that is your name of course) etc. We are all bladesmiths and knifemakers here.  If you feel you need an exception or are having difficulty registering, send a personal email to the forum registrar here.  
Sign in to follow this  
Mark Tuck

buffing compound

Recommended Posts

Hey guys I'm working on putting mirror finishes on  couple of knives and I was wondering what kind of  compound to buy? I always take the blades to 1000 grit on my belt sander.

Share this post


Link to post
Share on other sites

I hand sand mine up to 3,000 "paper" (more of a spongey pad) from Advanced auto parts. Its still not a true "mirror" polish, but I don't think that's even possible on steel. 

Hand sanding gets a finer finish than belt sanding IMHO and at 1,000 grit I don't think you're ready for compound yet. Lots of people use "Mother's Metal polish" and rotten stone for hamons. I just use the 3,000 grit paper though. 

Share this post


Link to post
Share on other sites

You are going to want to go higher than 1000 grit, 2000 at the minimum.  I would suggest a green compound, which is supposed to polish hard and soft steels.  If you look up "stainless steel polishing compound", green compounds come up.  I am not a big fan of mirror finishes, so I don't do them, but to each their own.  Good luck with it!

Share this post


Link to post
Share on other sites

For a full mirror finish you will want at least three compounds and different wheel types.  Jantz Supply has a good description of the process in their catalog.  They recommend starting from a machine finish 1000 grit to a sisal wheel with an emery-based cut-and-color compound followed by a felt wheel and a green compound for stainless, white diamond for non-stainless, and finally red rouge on a loose muslin wheel.

Never forget the buffer is the most dangerous tool in the shop and is trying to kill you at all times!

  • Like 1

Share this post


Link to post
Share on other sites
16 minutes ago, Charles du Preez said:

Sorry for the hijack and newbie question, @Alan Longmire what is so dangerous about the buffer?

They have a tendency to grab onto whatever you are buffing, and throw it at high speed.  Even if you are being very careful to make sure a knife would get thrown away from you rahter than into your groin or chest, the act of ripping the blade out of your hand can cut some finger off.

Maybe buffers should be added to that list of "Things you don't realize can kill you"

  • Like 1

Share this post


Link to post
Share on other sites
26 minutes ago, Charles du Preez said:

Sorry for the hijack and newbie question, @Alan Longmire what is so dangerous about the buffer?

When I took machine tool our instructor showed us pictures of a guy with a Phillips head screw driver lodged into his pelvis. He had been polishing the rust off, had it ripped out of his hand and straight into his crotch. Very sobering lesson to a bunch of teen boys let me tell you.....

Share this post


Link to post
Share on other sites
8 hours ago, Charles du Preez said:

Sorry for the hijack and newbie question, @Alan Longmire what is so dangerous about the buffer?

Knifemaker Gordon Dempsey was killed in his shop when a buffer grabbed a knife he was working on, threw it at him and pierced his heart.  That is why I will only use the bottom half of the wheel turning away from me.  

  • Like 1

Share this post


Link to post
Share on other sites
12 hours ago, Wes Detrick said:

Knifemaker Gordon Dempsey was killed in his shop when a buffer grabbed a knife he was working on, threw it at him and pierced his heart.  That is why I will only use the bottom half of the wheel turning away from me.  

Spot on correct Wes if your blade is above the center line of the buffer you run the risk of having it thrown back at you...Personally in addition to keeping the blade below the center line of the buffer I make sure my body is never directly infront of the buffing wheel...Ie...I stand off the the side a bit

 

Share this post


Link to post
Share on other sites

I don't buff blades, but I have had a briar pipe bounce off my shoulder and somewhere in the garage there's a sterling silver pin I never found.  And that's with a slow speed machine running around 1100 rpm.  Don't know if I'm man enough to use one that runs at 3200 rpm...:ph34r:

Share this post


Link to post
Share on other sites

Before I realized how dangerous they were I had built a couple because I thought I had to use them. THEN I was warned about them. THEN I had my first "organic learning experience". After I changed my pants I reevaluated my needs, changed my methods and restricted my use to "If there isn't another way and only in the most cautious manner possible". It is NOT a case of "if" they are going to rip something out of your hands but "When" is it going to happen? I never get anything above the lowest 1/3 of the wheel and prefer to have it set up diagonally on a corner of the table with nothing under the wheels so when it happens the blade is, hopefully, flung  unimpeded far away with as little chance of a bounce back as possible. When I get a chance I'll post a pic of my "buffing station". 

ETA: I am looking to hear from 'Smith's who have used the cork, and other polishing belts, on their grinders.

Edited by Vern Wimmer
  • Like 1

Share this post


Link to post
Share on other sites

Fortunately I saw enough warnings on this subject, and still I got caught.

Even if you are lucky and don't get hurt, blades don't like being thrown like that.  Considering where you are in the process when polishing, it's never good.

My belt grinder is one of those models with a belt on one side and a stone on the other, stone is long gone and I've been meaning to make and fit a MDF/Superwood wheel on the open side to use for sharpening.

Fortunately a friend did some reading on that and thankfully pointed out you need to approach the machine from behind when doing this, so the wheel turns away from you.

Share this post


Link to post
Share on other sites

I think Gil Hibben was injured really bad (nearly died from bleedout, I heard) when a buffer threw a blade into his thigh and nicked his femoral artery. 

Share this post


Link to post
Share on other sites

Is it not better to have the wheel on the end of the motor that makes it run backwards (if you cant reverse the polarity) and then you can work on the top of the wheel with any 'caught and thrown' objects will automatically go away from you.

 

Share this post


Link to post
Share on other sites

That's the thing, though:  Once the wheel catches something it tends to take it all the way around, or at least 180 degrees.  I buff on the bottom third with the wheel running towards me from the top.  When it throws things, they come off the top in a high arc.

Share this post


Link to post
Share on other sites

One way around that would be to rig up an adjustable guard to sit very close to the back side of the wheel. In theory it would catch and deflect anything that the wheel grabs and tries to pull around.  Then you would be able to buff on the top side of the wheel with it turning away from you, and anything that the wheel catches "should" hit the guard and end up behind the machine.   You just have to remember to keep the guard adjusted tight to the wheel as it wears away.

Share this post


Link to post
Share on other sites

I only buff bronze blades. But if I do, I use a hand drill with cotton wheel, and clamp the blade  so it can't go anywhere. The only downside is that you sometimes slip off the blade, and the drill head scratches the blade. I've taped that, to stop the damage if that happens. I prefer having the blade fixed, and the drill doesn't have as much energy to throw things like a bench grinder does, which is basically a flywheel. 

Aside from that, I've just learned of polishing pads, that on steel blades I find give a much better finish. My girlfriend had them for jewellery making. I've played with a small patternwelded blade I made earlier, and used the pad to polish up the pattern. The pad I used is a 3M Microfine CT2. I always found that at a 2000 grit, I'd get a very matte finish particularly on steel, and wanted to buff to bring out the shine. But with that type of pad, no buffing is needed. I've read that the grit is 1200/1500, but the finish is much better then 2000 grit sandpaper.

Share this post


Link to post
Share on other sites

Good tip, Jeroen!  Alex, I and most folks have a setup with a board kind of backing up the wheels, and it does tend to deflect the larger objects into the wall (where they bounce right back!), but small stuff tends to get caught between wheel and guard.  This acts like a pitching machine by accelerating and adding backspin to the throw.  That's why I've never found that silver pin.  I heard the "ka-zing!!!" as it shot past my ear, and the pop and clatter as it bounced off the far wall and under the benches and possibly into another dimension.

Share this post


Link to post
Share on other sites

I almost bought a buffer off my boss. Now I know why I don't need one :) I much prefer not to get stabbed at a high rate of speed. This makes me question my grinding practices....

Share this post


Link to post
Share on other sites

Fair enough Alan.  I hadnt thought about small things like pins.  They can be just as deadly as a blade at high speeds.  We use large stand alone wire wheels at work to take oxidization off the edge of laser cut parts.  You have to keep the guards adjusted right or the SOB will suck the parts right out of your hands and spit them back at you.

 

Share this post


Link to post
Share on other sites

If you want that mirror finish on stainless use the PINK buffing compound that K&G in Arizona sells ,use with a loose buff wheel as a final buff.

 

Share this post


Link to post
Share on other sites

I'm going to check those 3M pads out.

Loose buffing wheels in a buffer are the epitome of "danger".

Share this post


Link to post
Share on other sites

Yeah, but a loose (i.e. unsewn muslin) wheel gives the finest finish.  Like I said, I do buff pipes and jewelry, and sometimes knife handles.  Not blades, but only because I'm not into a mirror finish on steel.  Wood and silver, oh, yeah!

I really don't mean to discourage people, I just want them to be aware of the danger that lurks for the unaware or, even worse, the complacent.  Buffers have a way of lulling you into a sense of security before trying to take your head off.  Never let your guard down, and always listen to that little voice that says "are you sure this is a good idea?" when using one.  Oh, and never buff loose chain.  Unless you want to be known as Ol' Three-fingers.  That's more of a jewelry thing, but again, I want folks to be aware.  If you have to buff a chain, wrap it tightly around a dowel rod first, and buff on the rod.

Share this post


Link to post
Share on other sites

A buffer is a tool, and a good one. It is dangerous- but it doesn't have to be dangerous to you if you know what you're doing. A lot of people have good tips- my personal addition is let the wheel, and the compound, do the work- not pressure. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×