Today I sent some calculations to Richard in ref to the rotational RPM's of a 10" diameter wheel.
I, know a sharpener that lives in the Northwest Territory of Canada who had a bad experience with compressed paper wheels.
My first paper wheels were purchase in 1992 at a well known knife store in Tennessee - and have never had anything BUT GREAT results.
INFORMATION FROM RAZOR SHARP:
You now own the worlds best sharpening system--it will put a great edge on almost any tool that can be held up to the wheels!
Please read the instructions and feel free to call Razor Sharp Edgemaking System at 1-866-419-4879 with any questions or concerns that you may have.
This system will put a honed and polished razor sharp edge on your knives and tools in just seconds. The wheels are made to be used on any ordinary bench grinder that turns over 3000 RPMs. The wheels in a standard 8 in Deluxe Kit are eight inch by three quarter inch with a five eighths inch arbor hole. The installed bushing converts them to a one half inch arbor hole. Simply remove the bushings for use on a five eighths arbor. These 8 wheels are intended for use on a five or six inch grinder.
We can furnish the system in various wheel diameters and thicknesses, with any size arbor hole desired.
. You will sharpen many knives or tools before needing to re-surface the grit wheel. The slotted wheel needs to be dressed occasionally with 60 grit sandpaper.
To Install wheels:
You will need to remove the guards from your bench grinder, as they are not needed with these paper wheels. Then install the gritted wheel on the right side of the motor, and turn it by hand to see if there are any bumps or nodules. If there is, take something blunt like the corner of a flat file and, with the motor running, just touch the wheel to remove any bumps. Next take the conditioning wax (yellow) out of the cup and rub it sparingly on the gritted wheel so that you can just see it. You should still the grit through the wax. Each time you start to sharpen, hold the wax on the wheel for a brief second. Eventually, wax will build up ou will not see the grit at all. The surface will be shiny and waxy. Be careful not to use too much wax. Doing so will destroy the effectiveness of the grit.
The Slotted wheel needs no pre-conditioning. Just put it on and whenever you start to use it, just touch it a little with the Rouge (white).
Do not over-tighten the nuts, snug is enough. Spin the wheels by hand. If a wheel wobbles from side to side, you probably have a bent washer! Washers get bent when a stone wheel is put on and the nut is tightened too tight. To get rid of the wobble, loosen the nut and turn the washer, or washers, just a little. Turn one washer one way and the other washer the other way. Snug the nut and spin the wheel. You might have to repeat this a time or two to minimize the spin out. A little side to side deviation wont hurt anything!
Sometimes, if a wheel is exposed to heat, or dampness, it will warp a little. To fix this place the wheel or wheels between two boards, clamp them tightly and keep in a cool dry place for a few hours.
Truing of wheels:
When you have the wheels running true dont remove them unnecessarily. When you put them back they will be in a different position and you have to adjust them again. Sometimes the wheels may be a little out of round. The grit wheel, out of round, can be fixed at time of re-surfacing. If the slotted wheel seems out of round it can be trued at any time. You may round the corners of the slotted wheel if you sharpen a lot of serrated knives.
Truing of wheels cont
Correcting out of roundness is easy. Take a piece of 60 grit sandpaper, wrap it around a flat piece of metal, (a flat file works fine) hold it lightly against the face of the wheel, you will feel the high spot. Keep holding it lightly against the wheel until it feels smooth. When the high spot is gone, the wheel will be nice and clean and flat across the face!
Okay, you are ready to start sharpening:
Time to think about the angle you want on your knife or tool. Proper angle depends on what you are going to use the edge for! Generally, if you are going to chop, dig or scrape with a blade, a 35-40 degree angle works best. For razors or a little rotary cutting wheel, a flat angle is best, 10-15 degrees. Most knives are 20-25 degrees. You will learn with practice just what angle works best for you.
Here are some ideas about angles:
Hold your blade or tool horizontal with the wheel, the edge facing the wheel and about halfway down the face of the wheel. Now you are 90 degrees in relation to the axis of the motor.
(Pic of angles here)
Okay...half of 90 degrees is 45 degrees. Those are the blades you are abusing, such as an axe, a machete, or a shovel! Half of 45 degrees is 22.5 degrees. Most knives are 20 o 25 degrees. Half of 22.5 degrees is 11.5 degrees, which is for Broadheads, Razor Blades, Rotary cutting wheels, etc. Just remember...half, half, and half and you have your three basic angles.
The above is intended as a guide to help you get started! With practice you will learn what angles work best for the type of blades that you are sharpening.
Now that you have an idea about the angle that you want:
Turn on the motor. You previously applied Wax to the face of the grit wheel. Touch the wax to the wheel each time you start to sharpen. Carefully hold your knife up there and pick the angle. (90-45-22.5-11.5) We recommend practicing with junk knives first. Be sure youre not turning the blade into the wheel!
Make a few passes on each side of the blade. The aim is to feel a burr or wire edge which means that both sides or tapers of the edge have come together. You need the burr all the way from the hilt to the tip. Just a little burr is all you need.
When making the passes across the grit, start at the hilt and go to the tip without stopping. Also, pull the tip away from the wheel when it is at about the middle of the grit. If you pass the tip clear across the wheel, you may round the tip of the blade. It is good to keep a wadded up paper towel in hand to wipe off the wax that is now on the blade. It makes it easier to feel the burr or wire edge. This burr tells you that enough metal has been removed.
When sharpening the old way on a stone, like our grandfathers did, one never knew when enough metal had been taken off. One just kept rubbing the knife on the stone until one thought it was sharp enough!
Occasionally a knife will not develop a burr. Instead there is a hair on the edge that you can see. We call this angle hair or a feather edge. It is nice to have a good light handy.
Notes:
Now that you have acquired a burr or feather edge:
It is time to switch to the slotted wheel.
Take the white chunk of Jewelers Rouge and with the motor running rub it lightly on the face of the slotted or plain wheel. This is for heat control as well as polishing. Remember your angle, start on the side the burr is on, and make a pass. You do not need much pressure. Then make a pass on the other side of the blade. Repeat this, alternating sides, for three or four passes. Wipe off your edge and take a look at it. It should be getting pretty sharp. When you become adept at this, and ordinary knife blade may take 10 to 15 seconds from dull to razor sharp!
Dont be discouraged if your first try does not seem to work. It does take a little practice, but the results are worth it!
The Grit wheel is going to seem very aggressive the first 4 or 5 knives until it looks smooth and waxy. Be careful not to put on too much Wax. If you do the Grit cant do its job!
You will not have a heat buildup as long as you keep the edge moving and keep the wheels coated with the wax or the rouge, depending on which wheel you are working on. If your dull knife has nicks or other bad spots, you can fix these on the grit wheel even to putting a new tip if the old one is broken.
Caution: always use eye protection and never turn the blade into either wheel!
Notes:
You can sharpen scissors:
Use only the grit wheel. Have the cutting edge facing down, (never into the wheel) and try to hold the blade at the existing angle. Start as close to the hinge as you can get and work towards the tip. Usually it only takes a couple of passes to acquire a burr. Do the same thing with the other edge. Now you should have a burr on both edges, but do not go to the slotted wheel. Just close the scissors, holding the edges together. Voila! The burr is gone and the scissors are sharp! Wipe them off with a paper towel.
In case there are nicks or bad spots, you will have to take off enough metal to fix these. Lots of later model scissors have one blade serrated. Do nothing with the serrated blade, just work on the smooth blade.
You can sharpen knives with serrated edges:
On most serrated knives, one side of the blade is flat. Hold this side almost flat against the Grit wheel, drawing it from one end of the serrations to the other. Hardly any pressure is needed, and you will have small burrs on each of the scallops on the other side. (Sometimes you have to hold just a slight angle, 4 or 5 degrees, it depends on the knife.) Now go to the slotted wheel and use the corner of the wheel, holding the serrated side where the burr is toward the wheel and draw it lightly across the corner of the wheel. Turn it over and run the smooth side flat against the wheel, and polish that side. Now the burrs are gone and the serrations are sharp!
Leather Punches:
Hold punch horizontal, adjust your angle, follow the edge on the Grit wheel until you acquire a burr. You may need to remove the burr using a piece of leather or the like. In case of a round punch, your burr is on the inside, so take a leather shoe string and rotate it around, pulling it out at the same time. This will bring the burr out so you can polish it off on the slotted wheel.
Wood carving tools:
Hold tool in front of the wheel, cutting edge down at a horizontal, right angle to the wheel, and adjust to the desired angle. Keep the edge flat against the wheel. You do not want a convex surface on the tool. The flatter the surface the better it will cut the wood.
The wheel is flat across the face, so hold the tool on a horizontal plane. The sharpened surface will then be flat. As there are many different shapes of cutting edges on carving tools, t is not practical to try to describe how to hold each one.
Gouges need to be rotated with the sloped edge against the wheel. Chisels and V tools will require going from side to side on the wheel. After acquiring the burr go to the slotted wheel and polish on the burred side, holding the tool as straight up as possible. You may want to polish the sharpened side also for a nice mirror finish. For gouges and some other shapes, your burr is inside and you need to take it off on the corner of the slotted wheel. By using the slotted wheel to get rid of the burr, your tool will be sharp!
Reconditioning Grit wheel:
Use real coarse sand paper (about 36 grit) and clean all the grit off, down to the bare paper. Use 60 grit to true the wheel (it might be a little out of round), square off the corners and get it nice and smooth. Turn off the motor, but do not remove the wheels. If you do you may have to eliminate some wobble when you put it back on. Hand turn the wheel and put a thin bead of Elmers white glue on the face of the wheel, then spread it with your finger until there is a thin layer. Next, put some newspaper under the wheel to catch the excess grit, hand turn as you sprinkle the black Silicon Carbide powder on top of the glue. Go around 2 or 3 times until it looks good and no more will stick. Sometimes the powder will soak through the glue and youll need to sprinkle on a little more. When you are happy with your coating job, pour the excess back into the container and replace the lid.
Do not touch the wheel until it dries, preferably overnight, then its ready to go again! There is enough Grit in the kit to recoat the wheel 20 to 25 times.
Heres a couple more ideas:
It is easier to repair bad nicks in a blade, or broken tips (reshape the end) using a belt sander. Be sure to keep water handy, as a belt sander will heat a blade very fast!
If for any reason (maybe arbor size) you need to enlarge the hole use a drill press. Put the wheel on the press with a board under it. Center the wheel by lowering a bit the size of the existing hole thru the hole. With this bit in the hole, clamp the wheel and the board securely. Change to a desired size bit, put another board on top of the wheel and clamp it in place. Carefully run your bit thru the boards and the wheel. Lots of caution so as not to get our hole off center.
Note: The system is available with any size hole you might desire.
. allright jason, if you want to end up hurt, go right on ahead. i just wanted to say that the way i sharpen is the way i do it myself. to some it might look bad but in the 17 years i have been doing it, i have never been cut or injured this way but like i said, its the way "I" do it. culpeper has been sharpening the way as suggested on the wheels website, with the spine facing up and the edge down. the wheel is rotating in the direction of the edge which is counterclockwise. in a single motor unit like my PORTABLE unit that i carry in my vehicle, the motor is on my left, the wheel rotates to me. new users i strongly recommend using the method culpeper uses. and like norm on hometime says, there is nothing more important in shop safety than safety glasses. even a face shield on top of that isnt a bad idea as with anything that throws sparks.
. i'm sure if you buy it for him he would be glad to use it.
