Bench Grinders as Buffers

Stacy E. Apelt - Bladesmith

Stacy E. Apelt - Bladesmith

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It has been mentioned lately about using bench grinders to buff with. I was answering an email from a new maker and gave him this advice. I thought it probably is time to bring this subject up again.

The basic facts of life:
I know people are going to want to buff knives.
I know they will do it even if people tell them it is dangerous.
I know they think they know how to do it.
I know someone will chime in and say, " I buffed all my life and never hurt myself."

What a user may not know:
Buffers can be VERY dangerous.
They can maim you in 1/10 of a second.
Buffer injuries are common. I pretty much feel that anyone who says he never had a buffer incident is not being honest. That is about the same as a blacksmith saying he never burned his fingers.

Here is some advice that I gave in the email:
Buffing a knife is a very different from having used a bench grinder.
Be careful, keep a good grip, and NEVER place the blade anywhere but 3:00 to 5:00 position .... edge down.
Also, don't buff too hard or you can ruin the edge temper.
Also, a bench grinder with a buffing wheel is not the right tool. You need a long arm buffer that has plenty of clearance from the motor. About the only thing tat can be called good is they are usually low power and don't grab as hard as a 1HP unit. The wheel being too close to the motor makes you angle the knife, which will easily lead to snagging or burning the edge.
My buffers are about 28" end to end, and turn 12" buffs. They turn at around 1800RPM. Using a smaller buff will slow down the SFM, but not the RPM. Many of those 6" bench grinders turn at 3450RPM. So with a 6" wheel, they are running the same SFM as mine.
The smaller the wheel, the smaller the safe buffing zone. This means that you have a much smaller place to safely place your blade.

Some Basic Rules:
You must have total concentration.
Turn off the music/headset.
Get everyone else out of the shop. Pets, too.
Tell folks you are buffing and not to disturb you.
Don't buff when you are tired, have been drinking, are mad, or are feeling poorly.
Turn off your phone ringer, but keep the phone close by. It doesn't hurt to pre-dial 911.

I'll leave it to the rest of the chaps here to post their thoughts and experiences.
 
Excellent post...you can never overstate the danger of buffing wheels.

~Chip
 
My buffer is an 1800 RPM Baldor with 14" buffs, and it is by far the most dangerous machine in my shop. I nearly lost a finger to it a couple years ago, and just about a month back a flying knife barely missed my leg. I can't stress strongly enough how much I don't recommend a beginner to run anything close to it. IMO 8" buffs at 1800 rpm is a much safer starting point.
 
I’ve never had a desire for a buffed mirror polished blade, but discussions of how wonderful different woods look after buffing has made me want in for that purpose. Is there any different guiding principles to consider when wanting to buff handles rather than blades, or is it pretty much the same scare me into just buying some more sandpaper as above? :eek:
 
I can't remember who it was that said they made a plywood apron to wear while buffing. I thought it was a excellent idea!
Stacy E. Apelt - Bladesmith Stacy E. Apelt - Bladesmith
Maybe you can add to your original post the importance of buffer placement in the shop. Sometimes people don't read past the first post.
Like on a stand / not up against a wall or anything that the blade can bounce back at you.
Use something like old belts as a way to catch the flying blade.
 
Ed Fowler spoke to this about a year ago in Blade Magazine. Two things stuck: always have the buffer on its own stand with lots of room behind. His buffer has his old belts in a pile to catch flying knives. He recently tested this set up in the usual bad way. He reported that he was tired and lost concentration. Imagine that if Ed Fowler, hands down one of the greats screwed this up it bodes badly for those less famous. He also was very concerned about buffing on your work bench. Absolutly no where for the knife to go buy back at you. I took that advice very seriously and bought a stand from Harbor Freight. It just feels safer.
 
I don't post much (In fact this might be post #2 ) but my solution to this has been to keep the knife stationary, like in a vise, and put the buffing wheel in my portable drill.

I haven't seen this mentioned before. It works OK for me and seems much safer. Sometimes the knife grabs at the buffing material. But it's much easier to control a drill with a pistol grip handle than a flying knife. Even if I were to turn loose of it I might get banged up a bit, but I won't get sliced and diced like a vego-matic
 
I rarely use my buffer at all aside from a couple very light passes on waxed handles with a clean cotton buff. I don’t take my knives to a full perfect mirror either so the life span and safety of different types of cork belts has won me over. I should state that it’s a grinder not a true buffer. When I did use it years ago, I had a chunk of 2x2 about 18 inches long as a handle. I would place the blade in the center of the board, and run a few screws through the holes in the tang. This secured the blade and gave me a far larger piece to hang onto than it I was just trying to hold a knife by the tang. This system made it far less likely for the buffer to grab the blade and pull it out of my hands. Once I was done one side, I just flipped it and screwed it back on to buff the other side. If by some strange mistake it did manage to pull it out of my hands, it was far less likely to be spun around the wheel back at me.
 
seanj said:
I don't post much (In fact this might be post #2 ) but my solution to this has been to keep the knife stationary, like in a vise, and put the buffing wheel in my portable drill.

I haven't seen this mentioned before. It works OK for me and seems much safer. Sometimes the knife grabs at the buffing material. But it's much easier to control a drill with a pistol grip handle than a flying knife. Even if I were to turn loose of it I might get banged up a bit, but I won't get sliced and diced like a vego-matic
Click to expand...

This is a bad idea. While less likely to send the blade flying, it is far more likely to have the buff catch and the drill/buff circle around the blade.
 
Another two commonly seen bad ideas I feel worth mentioning are using a drill press as a buffer, and having the buffer turn backwards and working on the top of the wheel. I've seen both often recommended by beginners on Facebook.
The big problem I see with both of those is control. You won't have any at all in comparison to buffing properly. The argument they make is it will throw the knife away from them if it grabs, but that isn't valid. I have personally seen something fly nearly straight sideways off a buffer, and I have heard of (but not seen personally) knives sticking into the buff enough to make a partial or even full rotation before flying off in a random direction. And I forsee things like that happening would be a lot more common if you don't have proper control over the part, as would be the case with non standard orientation of the buff.
 
George Tichbourne was also injured after something (not a knife) he buffed struck him in the chest.

(he had large industrial buffers 3, 5, 10 HP ?

I think he took to wearing a padded bullet proof vest after that as subsequent blows may have worsened the original instance.
 
In industry those using grinders wear chain mail. IIRC, OSHA requires it if buffing sharp objects. I have also seen the padded jerkins that full contact recreators wear for sword fighting.
 
Slow the thing down. Do you guys really buff handles at 3450 rpm. I tend to use something like 4-600. Otherwise the wax gets too how anyway.
As far as buffing blades, all above is good advice although I still slow it down for better/safer control.
 
Stacy E. Apelt - Bladesmith said:
. NEVER place the blade anywhere but 3:00 to 5:00 position .... edge down.


Some Basic Rules:
You must have total concentration.
Turn off the music/headset.
Get everyone else out of the shop. Pets, too.
Tell folks you are buffing and not to disturb you.
Don't buff when you are tired, have been drinking, are mad, or are feeling poorly.
Turn off your phone ringer, but keep the phone close by.
Click to expand...
. Well Stacy & I must of grown up where there were different clocks :pbecause with the buffer in front of me with the wheel turning towards me I present the blade edge first in the third quadrant from the outside of the wheel which would be right at 7-7:30 on the clock! ————————my buffer, a 3/4 hp Baldor 3640rpm . I bought it used before I knew a 1720rpm is fast enough to really screw you up!:eek: —-I only use a buffer to take the wire edge off of a knife I’m sharpening and finish my knives with a combo of Scotch Brite & Cork belts for a fine satin finish!——Still I’ve had a few scary times at the buffer o_O:confused:——/////-I like that Stacy, under his basic Rules notes a few good times to not do any buffing like when angry, had some Adult Beverages, tired, and I’ll add, had a argument with the wife. I won’t work in my shop at all! Will not turn on any power tools and take my wife out to dinner, go for a walk if I was angry, or go relax or take a nap if I’m really tired. ———Guys you don’t want to lose digits or worse... Come back to the shop when your head is clear & you are refreshed and ready to work!!:thumbsup:
 
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golfer1 said:
Slow the thing down. Do you guys really buff handles at 3450 rpm. I tend to use something like 4-600. Otherwise the wax gets too how anyway.
As far as buffing blades, all above is good advice although I still slow it down for better/safer control.
Click to expand...


Good idea. It will slow down the process, but a durn 100 dollar knife ain't worth losing your life over.

anybody have a line on a true variable speed bench buffer? perhaps one with a VFD on it.
 
:pbecause with the buffer in front of me with the wheel turning towards me I present the blade edge first in the third quadrant from the outside of the wheel which would be right at 7-7:30 on the clock! ————————my

thinking bout that????...........

would that be backside from where you are standing ?
 
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