I have found that it is possible to do things wrong for so long that it eventually becomes right for you, I am living proof of that. However, there are ways to significantly reduce the learning curve, number one being to not continually reinvent the wheel, and many very skilled makers have put in years of trial and error to determine the most ergonomic and effective grinding techniques.

With this in mind I would say that sitting would work with a tool rest but for free hand it would create more problems than it could solve. By far the biggest “acquired” skill in making a knife is proper grinding, forging is actually way down the list, with grinding at the top. Free hand grinding, on a belt grinder, is something that takes a lot of time and practice to train your body to do well, and standing would be the most effective way to engage those skills. If seated you would have to work out the height just right to get the proper angle of attack, and then there would be a whole new set of concerns for spark travel. Standing keeps you fairly free of sparks when standing at a vertical platen, sitting would potentially present parts of your lower body to the spark path, at common grinder heights.

One way to do the free hand seated grind would be to get the platen low enough, or seat high enough, to get the working area between your knees so that you could use them for a very steady armrest and also send all the sparks harmlessly below. I could see this possibly working well for smaller knives, but I could not envision it all with larger blades, such as the swords I work with, where I need the full motion of my legs and torso to complete the grind. There are some who would say that they can do these blades in sections but I can often look down their blades and see those very sections in the final finish.

Of course, this is mostly regarding belt grinders with platens. Other grinding equipment could change things up. For example, rather that sitting, it was not uncommon for European cutlers to grind over wheels in a prone position. But for this conversation I am assuming we are talking the standard 2X72 knifemaking grinder popular today, for which I absolutely teach freehand grinding standing up.

So this poses another question:

If standing what is a good height for the 2X72 grinder to be set at? I thought it was a comfort factor so my tool rest is about belly button height on me. This was mainly based on what I've seen other have theirs set at and what seemed right to me without putting too much strain on back, shoulders, neck, etc. Personally I have neck issues so I try to avoid being in positions that would cause extended periods of neck strain.

This might be a loaded question because of different processes at different times on the grinder.

I had the idea of the proper height for years but it took teaching it for many more years to conceptualize it in a way that makes it very clear. You want your platen set to height so that the center of it rests just below the level of your elbows when you are standing relaxed at the grinder. Most shops will have their grinders set entirely too high for maintaining a smooth, clean grind. You can go lower, but not higher, or you will continually fight to keep a smooth accurate grind line. I teach this in all my classes and always include a clear demonstration as to the principles that make it so. Anyone can give it a try themselves- step up to a grinder and hold your blade against the platen at a point well blow your elbows, then slowly lift the blade to a point well above your elbows as you attempt to hold it smoothly against the moving belt. The reason behind this principle will quickly become apparent. Pulling, or dragging something into a moving belt allows it to ride smoothly over it, pushing, or lifting it above that fulcrum/pivot point of the elbow into the oncoming belt will be a jerky, catchy, struggle.

Simple, elegant explanation. I know what looking at when I get off work tonight!

The way the Kevin explains the proper height for a grinder, is basically the same as I do.

Now, when it comes to sitting at and modern 2 x 72" grinder, I am absolutely against it! You might get away with once....or even a thousand times, but sooner or later it will get you! I've personally seen a number of people injured because the where sitting, and lost their grip/control of a blade, and couldn't get out of the way in time. I've also had a friend die because he was sitting at the grinder. His wife came home from work, and found him in a pool of blood on the floor, with the grinding still running. Coroner report stated that the blade he was grinding on had completely severed his femoral artery. So nope! Unless there is no other choice (like some type of disability), 100% against sitting while grinding.

This bring up a safety note: Most of the machines in my shop are operated by momentary foot switches. Drill presses, buffers, disc grinders, etc. If something happens, you simply lift your foot/step back, and everything stops. Still not foolproof, but it's saved my bacon a number of times...particularity at the drill press and buffers. The only reasons I don't have them on my grinders is because of the power source, and the fact that when I grind, all the motion is is in my legs and body....so standing on a foot switch would really put a kink in doing that.

Sorry James, I promise I'm not trying to hijack your post <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//tongue.gi f' class='bbc_emoticon' alt=':P' /> but Ed made me think of another question:

Has the ABS ever had or thought about a safety committee/discussion board section/thread posting? This is a dangerous craft we are involved, with with all kinds of STCKY (Stuff That Can Kill You) situations. I'm thinking that maybe a continuing thread of safety related items like this topic, as well as electrical, chemical, product recalls, etc. could be beneficial and quite possibly safe a life.

I would be glad to help out with this as well since I'm on the safety committee at the power plant where I work and we get daily safety briefings.

Oh gosh.... don't get me started on "safety", because that brings in "common sense"... and I am absolutely dumbfounded at how it seems fewer and fewer have any these days! <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//blink.gi f' class='bbc_emoticon' alt=':blink:' />