How to use Felt Bobs

How to use the Felt Bobs and Wheels
Questions:

• 1. Why use the felt bobs and wheels for polishing?
• 2. What is the density of the felt bobs and wheels?
• 3. How to choose the density of felt bobs and wheels?
• 4. Where to attach the felt bobs and wheels and how?
• 5. How to charge felt wheels with compound?
• 6. How to store the felt bobs and wheels after finishing the work?
• 7. How to do the truing of a felt wheel or bobs?
• 8. how to choose the shape of the felt bobs and wheels?
• 9. Introduce an article?

Safety Issue:

• - Always practice safely when using power tools.
• - Please wear eye protection, masks, and gloves.
• - Please Keep children away from power tools.
• - Never use the felt bobs with loosen shank. The shank attached to the felt bobs and wheels must be very secure.

   Answers:

Question 1: Why use the felt bobs and wheels for polishing?

   Woolen Felt is a non-woven formation, relying on his own characters- wool phosphorus. Through pressure, heat and humidity, wool becomes felt. There are many advantages of Felt, thermal insulation as traditional usages, but also flexible, hard to loosen, can be cut into various shapes of parts as the polishing bobs and wheels ...

   Cross-section of wool is hard as rock, can be used for grinding materials itself.

   Felt can be an effective carrier of particles. The felt polishing wheel and bobs have better capability than other materials to accept the various polishing compounds and slurry. Abrasive particles are visible evenly in the capillaries of the felt, which uniformly polishing the required surface. Sheep wool is the best natural fiber of resilient material, because it can maintain its edge and shape throughout its life. As felt wears, the new surface has identical medium of polishing compound because felt surface does not get glazed. When the felt surface wears, a new surface has formed and holds the polishing compound to continue the polishing work. The felt surface does not get glazed.

   Felt good wear resistance, excellent sharpness, can be used to make polishing bobs and wheels for polishing precision instruments, jewelry, glass, metal, and denture ...Etc.

Question 2: What is the density of the felt bobs and wheels?

   Felt density is ，marked grams per cubic centimeter internationally, for example: Medium density is 0.60 gram/cm³. Felt bobs and wheels are available in four densities. Soft (0.50 g/cm³), Medium (0.60 g/cm³), Hard (0.70 g/cm³) and Rock Hard (0.80 g/cm³). This the unit thar expresses density around the world. The people in the factory used to call the density by 0.50, 0.60, 0.70, 0.80, instead of the Soft, Medium, Hard, Rock hard.

   In the feltbobs.com, we most carried are 0.50, 0.60, 0.70, 0.80, which means Soft, Medium, Hard and Rock hard.

Question 3: How to choose the density of felt bobs and wheels?

   It is exceedingly difficult to answer this question: which density is good for your work? It is mostly depending to what kind of metal you are going to polishing, and what kind of polishing are you using. Here two things should be considered:

   One. How much polishing material you want your felt bobs and wheels to hold?
The felt bobs and wheels with soft density can hold more polishing material.
   Two. What the surface condition are you going to polish?

   If the condition of surface is good, very little scratches, the hard density could be use. If the surface condition is not good, with significant scratches, then use soft density of felt bobs and wheels.
Always remember: The softer the wheel, the better for high luster or result.

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Question 4: Where to attach the felt bobs and wheels and how?

   Felt bobs and Wheels can be attached to name brand power tools like Black and Decker, Drexel, DeWalt, Makita and Ryobi. Large Felt Wheels can be attached to any bench grinder.

   We carry the felt bobs and mounted wheels in British measurement system and Metric system at feltbobs.com. Most of the power tools can hold both measurement systems.

In British system of measurement, the felt bobs have 1/8” shank and ¼” shank at felt bobs.com. The felt bobs below ½” have 1/8” shanks. The felt bobs above ½” have ¼” shanks.

   In Metric system of measurement, the felt bobs have 3mm shank and 6mm shank at felt bobs.com. The felt bobs below 12mm have 3mm shanks. The felt bobs above 12mm have 6mm shanks. The felt mounted wheels below 25mm have 1/8” shanks. The felt mounted wheels above 25mm have 6mm shanks.

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Question 5: How to charge felt wheels with compound?

If you apply abrasive to a new felt wheel (or felt bob) it is difficult because the abrasive does not stick to it easily.
Here are a few suggestions to make applying abrasives easier:

After starting the grinding wheel（or felt bob）, do not wait until the grinding wheel (felt bob) is running at full speed. Turn off the switch. Apply abrasive at this moment.
Another method is to add little quantity oil, which can be applied with a cloth. When applying oil. Please do not stand in the direction in which the felt wheel rotates, because the oil from the felt wheel will fly out. After applying little quantity oil, it will be easier to apply the abrasive.

The wetness and dryness of the abrasive will affect the effectiveness of your abrasive application. As the abrasive increases, the felt wheel develops a smooth surface. Adding abrasive later becomes easy.

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Question 6: How to store the felt bobs and wheels after finishing the work?

   With a little care, your Felt Wheels and Wheels can last a long time. At the end of your buffing and polishing, allow the felt wheel to continue to spin for 1-minute minutes so any remaining polishing compound residue can spit out. Then let the felt wheel air dry before storing it to prevent molds.

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Question 7: How to true a felt wheel or bobs?

   Surface irregularities of the felt wheel will cause vibration and make accurate honing difficult. Felt Wheels are "trued" on both sides at factory but it is a good idea to "true" your felt wheel if you are re-installing it or if you have been using it for a long period of time.

   It is a clever idea to remove any surface irregularities from time to time to increase the life of a felt wheel.

   First, using a piece of bar stock or other square-edged steel item, remove any build-up of honing compound prior to "truing" the felt wheel as the compound will clog the sanding drum.

   Then mount a 1/2" sanding drum fitted with a 60x sleeve in an electric hand drill. With both the wheel and the drill spinning, bring the sanding drum against the wheel. Make light passes following the contour of the wheel's face and sides until the wheel is no longer eccentric and is to the desired condition.

   Check the arbor nuts on both sides of the grinder as braking action of "truing" the felt wheel might loosen them.

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Question 8: how to choose the shape of the felt bobs and wheels?

   In general, according to the polishing surface you want to polish, you select the shape of felt bobs and wheels. The top and sides of the felt bobs, both can be used for polishing the contact surface.

   Bullet-shaped and cone-shape felt bobs are very similar. In feltbobs.com, we do not clearly distinguish the bullet-shaped cone-shape of felt bobs. Each product we have photos, photos taken from the actual products. You can see a photo to decide what you want for felt bobs.

   A little trick is: you can use fine sandpaper to change the shape of the felt bobs and wheels. The method is: first to mount the felt bobs or wheels to Power rotary tool, and then carefully use the sandpaper to touch the part you do not need, remove that part.

If you still have difficulty to find the right felt bobs and wheels for you, you can take a picture sent to us by e-mail, our customer service department will help you solve this problem.

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Introduce an article:

The polishing process, mirror finishing.

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