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View Full Version : Buffers, Maybe The Most Dangerous Machine In Your Shop.



Jim Adams Customs
04-15-2010, 02:21 PM
Nothing will wake you up faster than having sharpen knife flying across your shop.

Mike Carter
04-15-2010, 02:24 PM
Catching an edge on a grinding wheel can teach you to dance too.

James Terrio
04-15-2010, 02:51 PM
Now is a good time for me to ask a possibly dumb question...

With all the horror stories and ER pictures we've seen about people getting mangled in a quick second by their buffer, I got to thinkin'. I know, that's always dangerous with me.

Would it make any sense to use an auto-body type buffer?!? Vise up the blade, and bring the buffer to it? Seems to me, that way, it if grabs you might get kicked in the ribs by the buffer, but not sliced open like you would by a launched blade. I know which one I'd prefer, if I had to choose.

I apologize for not looking up the speeds those buffers run at, whether or not you can get the right buffs for them, etc. But I've buffed small, vised parts with a rotary tool and it worked just fine. Not practical for a full blade or handle though.

clancy
04-15-2010, 02:57 PM
what about using a buffing belt on your grinder? Do they work? They seem less dangerous than a loose buff.

James Terrio
04-15-2010, 03:06 PM
That's a good question, clancy. I've heard of people getting good results from leather belts/inside-out regular belts loaded with buffing compound, too. Never tried it though.

Doug Lester
04-15-2010, 05:01 PM
James, when I buff my blades, I actually prefer a satin finish which I do on the belt grinder, I pad the handle and clamp it in my knife vice then put a buffing wheel on my hand drill and use it.

Doug Lester

whiteeugene
04-15-2010, 06:35 PM
I have my buffer mounted off the table on a small shelf that is smaller than the base of the buffer. I also have rubber mat on the floor and on the side of the table. Not only has it saved me from dodging flying blades if they do get away the rubber helps cushion the knife. Nothing like working 2 days on a knife and have the buffer catch it and through it to the floor and crack the scales and scratch the knife up. You can pick up the rubber mat at the home store ask for matting that is used in a workout area.

BossDog
04-15-2010, 06:46 PM
I keep a chunk of styrofoam under my buffer wheel and a box behind it with rags loosely piled in to stop a bounce. It will really soak up the bounce but it won't stop it from stabbing me in the stomach. I hate loose buffs. I nearly always use 1/4" sewn buff and even those will grab a blade and chunk it pretty good.

Bill T
04-15-2010, 06:58 PM
I stopped buffing blades when my buffer took a knife out of my hands . It had a 4" blade 1/4" thick and when it hit the cinder block wall it bent 90 degrees . Can't imagine what it could have done if it hit me . Gil Hibben almost died when a blade went into his leg from the buffer . I still sweat when doing the handles...

Mike Carter
04-15-2010, 07:10 PM
I stopped buffing blades when my buffer took a knife out of my hands . It had a 4" blade 1/4" thick and when it hit the cinder block wall it bent 90 degrees . Can't imagine what it could have done if it hit me . Gil Hibben almost died when a blade went into his leg from the buffer . I still sweat when doing the handles...

Actually, it was a grinder that threw the blade into Gil's leg. He was standing and grinding when he dropped the blade. It stuck through the belt and it threw it back at him.

Bill T
04-15-2010, 07:16 PM
Sorry

clancy
04-15-2010, 07:20 PM
I had a friend that had a buffer grab his knife and stick it into his thigh. For several months after that he always wore a sheet of plywood armor when ever he buffed a blade.

James Terrio
04-15-2010, 08:07 PM
James, when I buff my blades, I actually prefer a satin finish which I do on the belt grinder, I pad the handle and clamp it in my knife vice then put a buffing wheel on my hand drill and use it.

Doug Lester

That makes sense too, Doug. More than one way to skin a cat, as they say!

FWIW I also remember seeing a thread where someone built a thick plywood guard that was mounted just below their bench-type buffer, angled inwards so it would either "catch" a thrown blade or bounce it under the bench away from the maker.

Maybe I'm paranoid, but I'm still thinking I'd rather toss a hand-held buffer around, rather than a sharp blade. *shrug*

UncleBillyKnives
04-15-2010, 09:15 PM
I finished a gut hook a couple weeks ago and that was real scary. The buffer just loved to grab it and test my blood pressure medication!

Uncle Billy

DropPoint
04-15-2010, 09:27 PM
My first post other than my post in the Intro so if this seems really dumb...well

Any rate I have a belt grinder that I got from Harbor Freight that has an attachment on the side for a six inch circular grinding pad. The kind you peel and stick.

Personally I haven't found a reason to use it for grinding so I bought an 8" buffing wheel and am planning to attach it. I'll have to take the guard off to get it to fit. Do a little drill and tap on the attachment and I'm good.

I figure if I buff on the downward side if it does throw it will throw to the back of the bench...right? Or at least downward.

I've done other shop work but this is my first venture into knives. I've had wood thrown at me before but a piece of steel is a bit different.

So is my idea crazy? My wife says I'm certifiable but that's a different story.

Mike Carter
04-15-2010, 09:40 PM
I buff nearly every knife I make. Buffers command great respect and your absolute concentration but they can be used safely. I do recommend 1750 RPM buffers. 3400 RMP is just too fast in my opinion.

I use relative hard wheels for blades as they are a lot less likely to grab the blade. The only time I use a loose wheel is for handles. Take a good stance, a FIRM grip on the knife, and never go above the center line of the wheel.

Be extremly careful when getting close to the top edge or the tip of the blade as that is where it will grab. This is especially true if you are polishing edge up.

Jim Adams Customs
04-16-2010, 12:42 AM
I have a TV in my shop. I turn it off when I buff. The buffer get all of my attention. Like Mike I buff very knife. I choose a 1/3 hp 6'' buffer 1760 rpm.
They can be safe. But you can't never let your mind wander. It will gets you.

bootstrap
04-19-2010, 08:22 PM
i started wear a thick welder's apron because of this. Scared the crap out me!

N.D.
05-10-2010, 12:23 AM
Sounds like maybe a custom thick plywood blade catcher type of guard covering the top & bottom of the wheel is in order, or even covering all of the unneeded areas of the wheel W the guard along W a clear Lexan or Carbon fiber riot shield between you and the wheel (like the cops & corrections Officers use)

Back in the day I had the buffer disarm me and throw the knife a number of times; VERY VERY SCARY, and as said earlier in the thread it WILL wake you up QUICK, and test your BP meds!!!!!!!!! :eek: Jaw Drop

I'm getting a bit of the shakes just thinking about it!

N.D.
05-10-2010, 12:36 AM
i started wear a thick welder's apron because of this. Scared the crap out me!

Good thread!

It can help sometimes but it still wont stop most blades if they hit you sharpened edge or point on, even chain mail wont stop lots of blades hitting you hard point on, I've seen a good sharp knife go through a ballistic vest by hand like it wasn't even there (no trauma plate) so it's kinda like tryin to stop a broad head from a long bow, you NEED something solid and tough to completely stop it from getting to your body.

Travis Fry
05-10-2010, 08:42 AM
Thanks guys, now I've got sweaty palms. I've never had a blade get tossed, but bolsters hurt pretty bad when they smack you too (when polishing the front edge before assembly). My buffer gives me the willies! I've found it also helps to keep loading it up with rouge, because more rouge polishes faster and better and I'm less inclined to use too much pressure (bad) and instead more likely to let the rouge do the work (good).

John Barker
05-10-2010, 09:06 PM
I built one of these for each of my buffers and they have been tested several times and work great.
-John

Jeff Pearce
05-10-2010, 09:17 PM
I built one of these for each of my buffers and they have been tested several times and work great.
-John

Great idea John... I need to make one...2thumbs

CDHumiston
05-10-2010, 09:46 PM
I have yet to have a blade yanked from my hand, I know I'm lucky. I'm also cautious as I'm sure most of us are. Here are my ideas...

I use a lower speed buffer 1750 RPM

I use sewn muslin wheels not the real loose ones

I always buff sharp edge down

I buff on the 3 oclock to 5 oclock position on the wheel

I don't torque the nuts down on my buffing wheels, this helped me by stopping the wheel rotation before it could take my knife from me when I apply too much preasure

I focus every bit of my attention to the task at hand, no distractions when buffing

I have heavy rubber mat on the floor under the buffing wheels just in case

I'm sure I'll have a knife ripped from my hand some day, but I am not affraid of or intimidated by the buffer. If you are affraid of your equipment it will bite you

I think I gave .05 on that one...

HELLGAP
05-11-2010, 03:13 AM
Chris I had a blade tore out of my hand and it scared the crap out of me. The knife flew around the buffer missed me by inches and hit the floor. It took a large chip out of the blade it hit so hard . I made it into a finger gaurd and thats a big chip. 3/4 inch long 1/2 deep in the cpm154. kellyw

CDHumiston
05-11-2010, 08:45 AM
I'm sure a blade can and will be grabbed by my buffer at some point. However as with all the rest of my power tools I'm still going to use it. I will respect it, but not be afraid of it.

The scariest tool in my shop became the drill press one afternoon. I wasn't using the proper bit and it basically welded itself into the knife. The knife was torn from my grip and went spinning around at about 200 RPM until it broke loose and flew all the way across my garage. All I could think about was the fact that it could have sliced my gut open from one side to the other.

I think alot harder about what I'm doing and if I'm using the right tool for the job now!

James Terrio
05-11-2010, 10:27 AM
Drill presses can be spooky, that's true. I too have had a workpiece yanked out of my hand and spin around. Luckily, I turned the press off, ducked, and it slowed to a stop before anything horrible happened. Nowadays I'm a lot more careful about my drilling technique, and clamp down anything that might kick my butt if it does catch as the bit breaks through. So far, so good. Another technique for longer pieces, is to line it up so the workpiece is against the column; Either way, if it does want to catch and spin, the piece can't go anywhere and the bit will probably snap. That's no fun, but it's better than having things fly across the room or into you.

Chris, I agree that we must respect our tools, but not be afraid of them. Fear makes you jumpy, and being jumpy makes you foul things up.

Never ever EVER grab at something that's falling or otherwise out of control! Chances are, it's either hot, sharp, heavy, or all three. Kill the power (if applicable) and get the heck out of the way.

John Barker
05-11-2010, 10:40 AM
Guys, one thing that helps with the buffing is to really take the blade up to the higher grits. I go up to 5 microns for all my blades, especially for hand satin finishes. I don't do a lot of mirror polished blades, but at one time I did. Anyway, if you take them to 5 microns it won't take but a minute to get a mirror finish. Less time on the buffer equals less chance of having an accident. Be careful.
-John