Knife Polishing Tips
This knife polishing guide will help you decide which wheels and compounds are right for your job. The choices may seem to be overwhelming, but keep in mind to achieve the desired results, polishing is usually a multiple step process. Determining how many steps are right for you will come with experience. We suggest you start with the finest compounds possible to do the job quickly and easily. You do not want to remove more material than necessary, but at the same time you do not want to spend three hours doing a fifteen minute job. The best way to learn is to experiment. You will want to start with a few pieces of scrap that you can play with to become familiar with the different compounds and how they cut or polish.
GREASELESS: Available in two types - plasticlad solid or brush on paste. Both are glue based and have a shelf life of 6-8 months. Special care should be taken to preserve these compounds. Most commonly used on muslin or felt wheels. When buffing aluminum with greaseless compounds always use LUBARlubricant to keep the material from tearing out.
PLASTICLAD SOLID: Available in grits ranging from 80 (coarsest) to 600 (finest). 80 grit plasticlad is very coarse and is used to remove deep scratches, rust and pits. 120 and 150 grits are coarse, used to remove rust, pits and scratches or buff marks left by the 80 grit. 200 and 240 are medium cutting compounds used to remove light rust and scratches quickly. 300 and 400 are light cutting compounds which will only remove small amounts of metal. 600 grit is a cleanup compound used mostly to remove wear marks from steel and brass.
BRUSH-ON: Available in grits ranging from 150-800. Lasts 4-5 times longer than Plasticlad once setup on the wheel, but must dry a minimum of 3-4 hours after being applied to the wheel.
GREASE BASED COMPOUNDS: Medium to fine compounds, 3-5 year self life.
EMERY: Black compound used for cutting. Use this compound when cutting action is desired but you do not need the power of fast cutting greaseless compounds.
CUT AND COLOR BARS: Available in medium and fine grades, these compounds have enough cutting power to achieve a dull satin finish using sisal wheels. Most often used to remove the scratches left behind by greaseless compounds.
BOBBING & CROCUS: Fast cutting compound often used on wooden laps, leather or brushes as well as felt and muslin wheels. Used to achieve a scratch free dull finish.
TRIPOLI: Cutting compound used extensively on brass, copper, aluminum, forgings, plastic and other similar materials. Follow with the blending bar to remove fine scratches.
BLENDING BAR: Closely related to the Cut and Color bar, this compound will remove very fine scratches. The blending bar is used primarily on a muslin wheel to achieve a bright satin finish.
WHITE ROUGE: Many projects call for a bright mirror finish, this is achieved with rouge. White rouge is the most popular of all buffing compounds. It is a general use compound used on carbon based steel, plastic, brass, fiberglass as well as other materials.
GREEN ROUGE: The perfect finish for stainless steel, brass bronze and nickel silver.
YELLOW ROUGE: Faster cutting rouge very popular for use on brass, bronze, copper and nickel silver.
JEWELERS ROUGE: Non-abrasive. Produces a lustrous finish on precious metals.
FABULUSTRE &ZAM: These specialty compounds are perfect for use on precious stones and metals. Will not discolor. Fabulustre is a dry compound which leaves very little residue. Zam leaves an invisible protective coating.
POWDERS: Used for hand rubbed finishes.
ALUMINUM OXIDE: Grits ranging from 150-800 most used to achieve a no line satin finish, cut with water to make a fine paste.
PUMICE: For use on steel. 80, used for scrubbing. 150 used for cleanup. 200, used for polishing.
TIN OXIDE: Mix with olive oil to polish glass, crystal, Plexiglas and fine plastics.
There are many things you need to know your wheels. The most important things to remember are to have a different wheel for each compound and always run the wheel in the same direction. Use a permanent marker to mark the wheel direction as well as the compound type on your wheel the first time you use it to avoid errors.
MUSLIN BUFFS: Made of high grade processed cotton. The versatility of these wheels make them very popular for general purpose use.
SEWN MUSLIN: Sewn muslin wheels can be used with virtually any compound making them the most versatile wheel made. Available in 1/4" or 3/4" wide and can be stacked for wider applications.
LOOSE MUSLIN: Used for final finish and cleanup. Also used without rouge to remove residue left after completing your buffing project.
POLISHING WHEEL: Super hard sewed and glued muslin wheel with canvas cover on each side for added strength. Most commonly used with greaseless compounds and cut and color bars.
SISAL WHEELS: Special wheels for use with cut and color bars. DO NOT attempt to use these wheels with greaseless compounds or rouge. They will not hold compounds other than the cut and color bars. When loaded with the cut and color compounds, these wheels will whisk away light scratches leaving your work virtually scratch free, however, they leave a dull satin finish. Sisal wheels are 3/8" thick and can be stacked and glued for desired thickness.
FELT WHEELS: Available in soft, medium and hard density. Soft felt wheels are very good on rounded surfaces and jobs requiring very little pressure or cutting action. Medium felt wheels adapt well to both flat and round surfaces and are most commonly used in the knife making industry. Hard felt wheels are most often used on flat surfaces or where it is necessary to use heavy pressure to contour the wheel to the surface of your project. Work well with greaseless compounds. Not recommended for use with rouges as felt wheels tend to burn with these compounds.
SATIN BRIGHT WHEELS: Used to remove light surface imperfections and blend finishes. Can be used wet or dry and can be washed free of contaminates after use. DO NOT apply any compound or rouge to a satin bright wheel.
FLAP WHEELS: Used for satin finish on steel, aluminum, brass and hard plastics.
EXP WHEELS: Aggressive, fast cutting, yet leaves a bright finish on hard materials such as steel and titanium.
CRATEX: Silicon carbide imbedded rubber available in 46, 90, 120 and 240 grit, used to polish, cut and blend scratches all in one operation.
WIRE WHEELS: Used for cleanup, surface conditioning and deburring on heavy rust. Used to remove scale after heat treating blades. Available in .008 or .014 wire gauges.
WHEEL RAKE: Used to remove access buffing compound from muslin and sisal wheels. DO NOT use on felt or satin bright wheels.
LUBAR: Lubricant used over greaseless compounds to avoid friction and heat build up. A must with aluminum to avoid tear out.
FACE SHIELD OR SAFETY GLASSES: Always wear eye protection to avoid dust particles and sparks.
DUST MASK OR RESPIRATOR: Protect your nose and lungs from harmful dust when buffing.
GLOVES: Wear gloves when buffing, this not only protects your hands but also makes cleanup easier.
PROPER CLOTHING: Avoid loose fitting clothing, ties, jewelry or other items which could get caught in the action. Proper shoes are a must.
Common Knife & Blade Polishing Questions
1800 OR 3600 RPM?
This has to be the most common question when it comes to buffing. It is also the most difficult to answer. 1800 rpm is safer for most operations, such as buffing a knife. Taking your time to remove the correct amount of material from the right places means all the difference in the finished product. Remember you can't put the steel back on the blade after you grind it off. Another advantage 1800 rom has over 3600 is friction and the buildup of heat. Plastics and epoxy melt with high surface speeds, so be careful! The 3600 rpm buffer has a place in the picture too. When working down rough pieces nothing beats the speed of a 3600 rpm buffer with a greaseless compound.
WHAT SIZE WHEELS DO I NEED?
You should check with the manufacturer of your buffer for the maximum wheel diameter for your machine. Remember the larger the wheel the faster the surface of the wheel is moving, bigger is not always better.
WHAT DO I DO IF MY WHEELS GET DIRTY?
Most contaminated wheels can be cleaned with a wheel rake or you can move them down to the next grit. Remember you can never use a wheel for more than one compound, once you have put 80 grit greaseless into o the wheel it is there forever. you can however put 120 grit onto a 240 grit wheel, it just becomes a 120 grit wheel forever.
WHAT IS THE BLACK STUFF?
After buffing you will see black residue on whatever you have been buffing. This is buffing compound, typically rouge. You can either wash the object with water, keep a clean buff to remove the residue, or dry buff by hand with a clean towel.
TYPICAL BUFFING PROCEDURE
Although every job will not be the same, it seems logical that we give some guidance to get you started. The following procedure utilizes the contents of the wheel and compound kit and shows a basic outline of a typical buffing operation.
- 80 or 150 grit greaseless compound on a felt or polishing muslin wheel to remove rust, scale and pits.
- 200 or 240 grit greaseless compound on a sewn muslin wheel to remove scratches created in step 1.
- 300 or 320 grit greaseless compound on a sewn muslin wheel to remove scratches created in step 2.
- 400 or 600 grit greaseless compound on a sewn muslin wheel to remove scratches created in step 3.
- Cut and color bar on sisal wheels to blend scratches from step 4. This will leave a dull fine line satin finish.
- Blending bar on a polishing or sewn muslin wheel to brighten and remove fine scratches created in step 5.
- White rouge on a loose muslin wheel to create a mirror finish.
- Wipe down with a clean dry cloth to remove any compound residue.
Get in touch!
We're happy to help you with additional knife polishing questions, or help you pick out the right gear for the job. Get in touch with us directly below: