Thursday 4 June 2015

Wool Pads I


Before the universal use of foam polishing pads wool or mops as they were then called were the work-horse of detailers. The reason for the poor acceptance of using a wool pad my recent converts to detailing is the fear that they cut too quickly and it's very easy to strikethrough on panel seams and edges. Wool pads run cooler than foam so its more difficult to ‘burn’ paint and tests proved that on average it took 80% longer to polish through an edge using a wool pad compared to a foam pad and an ordinary cutting compound. 

Always choose the least intrusive product, it is preferable to polish 2-3 times to restore the paint film surface than to use an unnecessarily abrasive machine polish / foam pad combination. Before commencing polishing do a test panel on the car, once you have achieved the desired results with the chosen polish / pad combination proceed

Wool vs. Foam

                Pro -faster cutting generates less friction induced heat and therefore leaves the surface cooler, removes heavy oxidation much more efficiently than a form pad. Use foam pad for slower and finer cutting.  Wool pads are easier to control compared to foam. They glide as the wool nap ‘lies down’ and will conform to vehicle body shape easily. Make certain to spur the wool fibres when it loads up with product.

                Con -wool can leave micro marring (buffer trails) finish with a foam pad to remove. Don’t overwork the polish as wool will break diminishing abrasives faster than foam, the surface lubricants will dry up faster and you could end up dry buffing unless you’re careful.
There are too many variables with different wool and foam types, along with too many compounds to give a definite choice.

General notes
1.        Cut with wool pads; (foam produces the most surface friction heat) and finish with foam pads, the fibres of the wool pad leave a very fine micro marring on the paint surface.
2.        Speed, the general rule is; limit speed on wool pads to 1500 RPM The bigger the pad the faster the cut, the coarser the compound, the faster the cut, the more aggressive the pad, the faster the cut Wool cuts faster than lamb’s wool, foamed wool is next and then foam. You pay the price for polishing too fast with swirl marks caused by the compound and pad combination.
3.        Compared to foam; wool pads have a larger available cutting surface area per square inch, which is due to the structure of the individual wool fibres compared to that of foam, allowing faster cutting action with less friction heat, utilizing less downward pressure
4.        Wool pads have a soft, long nap, which will not allow changes of direction easily due to the resistance of the nap. They are more suited to the centrifugal action of a circular polisher as opposed to a random orbital action
5.        The application of water - is not needed to supplement surface lubrication, but it helps to free the abrasive from sticking to the wool fibres. It also helps the pad to conform to surface contours more easily, effectively increasing the surface-area. Note- it may increase the abrasive abilities of the pad.

Notes:
1.        Use only quality natural wool pads, wash and rinse thoroughly before use (or use pre-washed)

2.        It is preferable to polish 2-3 times to restore the paint film surface than to use an unnecessarily abrasive polish / foam combination

3.        Wool pads are not recommended for random orbital machines (Porter Cable 7424, etc) most don’t have the torque available to overcome the surface resistance of a wool pad and their fibres works more efficiently with a centrifugal motion.

 If the nap (fibres) of the wool pad is longer than the eccentric offset (stroke) of the random orbital polisher (5/16 –inch) the effective transfer of energy will be lost it’s a question of physics, not just mechanics. Foam cutting pads tend to be much’ stiffer’ than wool fibres and thus will transfer the movement of the machine to the paint surface more efficiently than a comparable wool pad on an orbital polisher.

4.        A random orbital polisher with forced rotation (Flex 3401) is the exception to above,  along with short nap wool pads (actually one is a hybrid wool / foam) Lake Country Purple Foamed Wool, and Surbuf® pad with MicroFingers®as the forced rotation supplies a necessary centrifugal motion and the torque required to overcome surface resistance

5.        Natural wool is most aggressive - 50/50 wool/acrylic blends intermediate -  lamb’s wool  the least aggressive

6.        Always use the least aggressive product first, evaluate the surface, then only if necessary `step-up' to a more abrasive product and / or pad.

7.        Always use the least aggressive product first, evaluate the surface, then only if necessary `step-up' to a more abrasive product and / or pad.

Pad cross contamination

·         Clean and / or replace pads as often as is necessary; a clean, primed and seasoned pad will enhance the abrasive abilities of the compound / polish and make the process not only more efficient but less time consuming.

·         Do not use the same pad to apply differing products as cross contamination will reduce the effectiveness or completely negate their purpose altogether.

·         If you thoroughly clean pads right after use you shouldn't have any problems with contamination from different grades of polishes or compounds. However do not use the same pads for different sealants, or use a pad that has applied a sealant as a polishing pad or vice a versa.

·         Some polishes or sealants may be difficult to completely remove product residue. It is good practice to use a new or freshly cleaned pad with each type of car care product

Wool Polishing / Compounding Pads

Are used to cut or level a paint film surface with an abrasive machine polish (or compound) or to apply a polish to large surface areas. Aggressively removes 1500 - 2000 grit scratches, but will leave hazing, use a foam pad and a finishing polish to eliminate. Wool pads are made from various mixtures of wool and other materials (natural wool, foam and wool, blended wool and synthetic wool) Like foam a wool pads abrasive ability is closely tied to its composition i.e. generally the ‘softer’ the wool the less aggressive the cut

Backing plates

A rotary polisher has 5/8-inch (14mm) diameter shaft, an orbital polisher has a 5/16-inch (8mm) female thread.

The backing plate directly transfers the kinetic friction (energy) of the machine to the paint surface via the pad. The larger the backing plate (in relation to the pad) the greater the surface contact area so less energy is wasted. The foam pad will absorb the amount of orbital movement produced by the machine polisher unless sufficient pressure is applied to compress the pad (to approx 50%). Using a properly sized backing plate allows for the equal distribution of pressure across the entire face area of the pad; making it more efficient; as a  backing plate only compresses  the area of the pad that is directly underneath it.

 If the backing plate is too small for the pad, you reduce the effective contact surface area of the pad that is able to polish effectively,  t here is also a possibility that the backing plate will ‘cut’ the foam causing it to fail?

Allow a maximum of ¼-inch as a safety margin (i.e. 6.5 -inch pad- 6-inch backing plate, 5.5-inch pad -4.75-inch backing plate)  this will allow the maximum pad surface contact area, and equal pad compression over the pad contact surface ensuring efficient polishing

Always use the recommended sized backing plate for the pad you are using. Do not use a backing plate that is larger than the foam or wool pad.

Flexible backing plates - 6 .25-inch (160mm) used with the Lake County (LC) CCS 6.5 inch pads. High strength moulded urethane grip-easy edge for fast, easy pad changes, durable moulded polyurethane construction, flexible centre hub ideal for surface contours, plated steel threaded insert (5/8 -inch 11pi female thread or a metric size 14mm)  and steel reinforced inner construction
When trying to remove deep sanding marks, especially if they are close to an edge or a seam a stiffer backing plate is advantageous

3M 125 mm Perfect-it III Rotary Backing Plates are made from an impact resistant synthetic nylon plate bonded to a 25 mm thick layer of dense cellular foam, and are ideal for use with threaded rotary machine polishers such as the Makita 9227CB The highly flexible design allows for very easy transitioning from flat to contoured surfaces, and the hook and loop backing material enables quick and easy pad changes (M14 metric an 5/16th – inch US)

3M 125 mm Perfect-it III Rotary Backing Plates are made from an impact resistant synthetic nylon plate bonded to a 25 mm thick layer of dense cellular foam, and are ideal for use with threaded rotary machine polishers such as the Makita 9227CB The highly flexible design allows for very easy transitioning from flat to contoured surfaces, and the hook and loop backing material enables quick and easy pad changes (M14 metric and 5/16th – inch US)

Trailing and Leading Edge

Looking at a pad that is on the paint surface; the trailing edge is the left side (between 7 and 5 o'clock) and the leading edge is the right side (between 11 and 1 o'clock)

A light sensitive approach is essential, using only the weight of the machine, on vertical panels just enough pressure to maintain contact with the surface (without applied pressure) use a lower speed 1000 – 1200 RPM and keep the pad moving. Tilt the contact edge of the pad a few degrees so that only the leading edge of the pad is in contact with the paint surface. Make sure the leading edge (right hand side) of the pad on a rotary polisher is rolling off the panel so that would mean the right side of the pad is rotating off the panel.

If you have the trailing edge (left side) of the buffer on the edge it will tend to strongly force the machine out of your hands and burn the edge almost instantly.

Paint Removed by Polishing

Using a medium abrasive polish and a rotary polisher will remove approximately 0. 1 Mil (2.5 ยต (Microns)) from the paint surface (typically 4 passes at 1500-1800 RPM)  but there are many variables such as polish/compound and speed / pressure used that may affect the paint removed) 
There comes a point when you must judge wither removing a scratch will compromise the clear coat and if so you’ll have to ‘live’ with the imperfection.

If you have reservations about the amount of paint surface removed or the amount of paint coating remaining the use of a paint thickness gauge (PTG) is arbitrary

These numbers are offered as a guide only, as there are too many variables to provide any more than an approximation.

 Wool pad composition

The make-up of the type of wool is a significant factor. As you get away from 100% wool to synthetic and from four ply to single ply and increased height, the pad becomes softer and better for producing a finer finish. (See Note 4)

The twisted yarn is known as ‘ply’;  a 4 ply pad, it means that the yarn is twisted 4 times, There are pads that are  2 ply, single ply (no twists) and combinations, where sometimes every other strand of yarn is twisted. The more twists or higher the “ply”, the more aggressive the pad will be

A wool pad is graded is by what’s called “pile height”. Generally the thicker (higher) the pile height, the more aggressive the pad will be. Wool pads vary from a 2- inch pile height while some pads have pile heights at about 7/8’s of an inch. Manufacturers control a pad's aggressiveness by increasing or decreasing the nap height. As you shorten the length the pad becomes much more aggressive because the individual wool strands are able to stand on end more readily. This creates a scrubbing action whereas the longer strands lay down almost immediately when used.

                Notes -
1.        Wool pads are not recommended for random orbital machines (Porter Cable 7424, etc) as wool pads nap / fibres works more efficiently with a centrifugal(circular)  motion as opposed to centripetal (orbital) force, they also have more frictional resistance than a 7424 can overcome due to the limited torque available
2.        If the nap (fibres) of the wool pad is longer than the eccentric offset (stroke) of the random orbital polisher the effective transfer of energy will be lost
3.        Foam cutting pads tend to be much’ stiffer’  than wool fibres and thus will transfer the movement of the machine to the paint surface more efficiently than a comparable wool pad on an orbital polisher
4.        The Flex XC3401VRG Dual-Action Polisher due to its forced circular rotation is an exception to (1) above The two wool pads (actually one is a hybrid wool / foam) Lake Country Purple Foamed Wool and the other is a Micro-Surface® TufBuf Black natural lamb’s wool polishing pad
5.        Natural wool is most the aggressive - 50/50 wool/acrylic blends  are intermediate -  lamb’s wool is  the least aggressive
6.        Always use the least aggressive product first, evaluate the surface, then only if necessary `step-up' to a more abrasive product and / or pad.

Pad application guide - http://www.lakecountrymfg.com/padappguide.html

Wool Pads

 3M™ - Finesse-it™ buffing pad made from wool fibres 5.25 – inch diameter x 15/16 trim length, with a Hookit™ attachment system.

Superbuff™ III Wool Pad (PN 05703) and Perfect-It™ III Wool Compounding Pad (PN 05719)

Finesse-it™ buffing pad made from wool fibres 5.25 – inch diameter x 15/16 trim length. Has a Hookit™ attachment system.

Micro Mesh TufBuf

These black lamb’s wool polishing pads are made from natural lamb’s wool, it leaves clear-coat finishes with less haze and micro swirls than conventional foam or wool polishing pads. The dense pile material; 60,000 fibres per square inch versus 13,000 per square inch for synthetic pads, this pile surface distributes and applies material evenly and consistently. A very soft 100% lamb’s wool pad can be used for final (finesse) polishing.

Edge wool pads

Edge 2000 6 -inch Wool Buffing Pads are made of twisted wool. Twisted wool is denser and more abrasive than non-twisted wool. Also, the variety of wool and percentage of wool affects each pad’s “cut”.
 In order of aggressiveness - White, Blue, Green, Yellow and then Black

1.        Black Heavy Cut - 100% Domestic Wool Pad - suited for deep swirls, severe scratches, pitting, and defects. It removes wet sand marks and severe oxidation with the help of a compound or heavy cut swirl remover.
2.        Yellow Medium Cut- 50% Wool, 50% Wool Acrylic Pad - moderately aggressive, it removes swirls and moderate scratches, and reduces significant pits and deeper scratches. Use a swirl remover with the yellow pad when aggressive cutting is not needed.
3.        Green Light Cut - 40% Wool, 20% Acrylic, and 40% Rayon Pad - produces beautiful results with one step cleaner polishes. It has enough cut for cleaning the removing very light imperfections on paints that are in overall good condition.
4.        Blue Finishing - 70% Acrylic, 30% Wool Pad- for general polishing and gloss-enhancement, the blue pad can be used with any finishing polish to bring out a fine lustre on any finish.
5.        White Ultra fine Finishing - Australian Lamb’s wool Pad - this 100% lamb’s wool pad adds a mirror-like glow to the paint. Use the baby-soft lamb’s wool pad with a glaze or ultra fine finishing polish. This should be the last pad that touches your paint before wax application.

Natural wool

Leaves clear coat finishes with less haze and swirls than conventional polishing pads, fibres can be compressed and still recover their natural shape, less shedding, as they are manufactured with more fibres per square inch than synthetic wool pads. A denser pile surface distributes and applies material evenly and consistently, natural fibres are tapered with no splattering of applied materials and less scratch marks.

Micro Mesh TufBuf®

These black lamb’s wool polishing pads are made from natural lamb’s wool, it leaves clear-coat finishes with less haze and micro swirls than conventional foam or wool polishing pads. The dense 0.75 - inch pile material with 60,000 fibres per square inch versus 13,000 per square inch for synthetic wool pads, this pile surface distributes and applies material evenly and consistently. A very soft 100% lamb’s wool pad can be used for final (finesse) polishing as it’s even softer the LC CCS Gold Ultra soft foam

Foam and wool

These pads are a compromise with the safety of foam and the polishing ability of natural wool; a patented process encapsulates the base of the lamb’s wool fibres with microscopic polyurethane foam particles. Cuts like natural sheepskin but finishes like a foam pad, the foamed fibres resist matting and compression. The foaming process also creates minute air pockets at the base of the fibres, which improves cushioning and retention of compounds and polishes.

Wash in the patented System 2000TM Pad Washer or hand wash with warm water and mild soap, then air dry

Purple Foamed Wool Pad (PFW)

Lake Country Mfg. (LC) developed these pads for high production, OEM/Industrial users. Aggressively removes 1500 grit scratches, leaving a lustrous finish with no hazing by reducing compounding swirls while retaining a high gloss. Patented process encapsulates the base of the lamb’s wool fibres with microscopic polythene foam particles. Cuts like natural sheepskin but finishes like a foam pad. Foamed fibres resist caking and matting, foaming process also creates minute air pockets at the base of the fibres, which improves cushioning and retention of compounds and polishes.

A rotary at 1500 RPM coupled with a primed PFW, on a 24 x 24 – inch working area for approximately 1 minute; aggressively removes 1500 grit scratches, leaving a lustrous finish with no hazing by reducing compounding swirls while retaining a high gloss.

Wool pads are not recommended for random orbital machines (Porter Cable 7424, etc) as wool pads nap / fibres works more efficiently with a centrifugal motion.  Foam cutting pads tend to be much’ stiffer’ than wool fibres and thus will transfer the movement of the machine to the paint surface more efficiently than a comparable wool pad on an orbital polisher

MicroFingers® Surbuf

R Series applicator and buffing pads (0/10 Cut) feature patented micro fingers technology and are designed specifically for use on random orbit polishers with hook-and-loop fastening. Once the pad is primed, use three small dots for additional sections and clean the pad by brushing or compressed air after each section.

The independent, non-tufted vertical fibres work like the fingers on your hand. They flex or stiffen when necessary to reach the peaks and valleys found on any painted surface, metal, plastic, glass, wood, Fibreglass, Gel coat or wood. Use with any polish, compound, wax, sealant or liquid cleaner other solid surfaces. This constant flexing and stiffening action produces uniform results over the entire surface, adding depth and brilliance of shine not found in other products.

The tiny orbital movement of a Dual-Action polisher constantly exposes all of the 'sides (360 degrees)' of the MicroFinger so the amount of polishing actually working against the paint is far greater than the amount of polish a foam pad can engage.

Available in 6.5" Velcro™-back buffing/polishing pads, the velvety soft, fine nap micro fibre pad is a perfect fit for a rotary orbital or HS rotary polisher. It easily replaces wool pads and doesn't leave holograms; finally eliminate the worry of using wool on clear coat. Do not allow products to dry in the pads.

Using moderate pressure (otherwise the fibres will flatten rendering them ineffective) this pad exhibits very little surface resistance, due to the MicroFingers extremely short nap, thereby allowing an orbital polisher to rotate at almost at its maximum speed (#4). 

Due to its unique design the pad allows plenty of air to circulate, thereby reducing surface heat transfer, even during heavy cutting.

It absorbs very little product and unlike wool it is ideal for use with an orbital polisher. The Surbuf pad produces a very similar surface finish to a LC Purple Foamed Wool pad. Apply 4 dime sized ‘dots’ of polish and use very little downward pressure. Surbuf pad also generates less heat than most cutting foam pad. Always clean pads immediately after use.

Blended wool
A mix of wool and synthetic materials, this could be wool and yarn for cutting, wool and polyester for polishing, the more synthetic material content the more abrasive the pad.
 Synthetic wool
This material produces heat very rapidly, so be very careful with these pads as they can quickly cause damage to a paint surface and can cause major surface marring a four-ply twisted synthetic wool pad can destroy a clear coat in a very short time.
 4 Ply 100% Twisted Wool
Each strand of high grade wool fibre is tightly twisted, allowing our pad to stay at a consistent level of aggression for longer periods of operation. Choose 3 inch, 4inch, and 5inch diameters with a 1/2 inch or 3/4 inch pile height.
Choose shorter pile for your most aggressive compounding and longer pile for aggressive compounding with greater durability.
50/50 Wool Acrylic
A unique fibre combination for light compounding comprised of 50% 4 ply twisted wool and 50% single strand wool/acrylic blend. Allows the operator to accomplish a range of light compounding to heavier polishing tasks depending on the compound or polish used.
Electrified White Sheepskin
The electrification process removes the microscopic barbs from the hairs in the wool resulting in a soft and effective compounding material that does not scratch the painted surface. Choose 3 inch, 4
inch, and 5inch diameters with a 1/2 inch or 3/4 inch pile height.

TufBuf Black Natural Lamb’s wool Polishing Pad - Engineered to repair clear coat finishes, these premium pads are made from the finest natural shearling lamb hides available. The natural fibres of these pads are tapered with scales that cover each fibre.

Leaves clear coat finishes with less swirl or scratches than conventional wool or synthetic pads, fibres can be compressed and still recover their natural shape, the dense pile (60,000 fibres per square inch) of the pad applies and distributes compounds more evenly, with loop backing for easy on and off attachment to your back-up pad, available in a variety of sizes. A natural lambskin product, dyed black in colour with wool length in ¾ and 1-inch nap length

Urethane Backing Plates

Used by BMW, Mercedes and other European automakers in their assembly plants.

Advantages of Flexible, Urethane Backing Plates
·         The Velcro® brand fastening material is moulded into the plate eliminating delaminating.
·         The flexible edge reduces spontaneous heat build-up when transitioning from flat to contoured surfaces. These plates are recommended for compounding, polishing and finishing "soft" German clear coats.
·         Vastly reduced heat transfer keeps motor heat from being transferred to the paint surface.
·         Plated steel threaded insert will not cross-thread.
·         Reinforced inner construction uses steel struts moulded into the centre hub for superior strength.
·         Bevelled outer edge allows easy pad removal and replacement.
·         5/8 – inch x 11 female thread is for US/CA rotary fitting.
·         UK/EU is M14

Lake County (LC) - 43-125WH Grip Easy™ Moulded Urethane (5/8" x 11) 4 7/8" (125mm)
3M Perfect-it III Rotary Backing Plate  - 125mm two  different female thread sizes;  M14 EU (09552) for use with threaded rotary polishers - Makita 9227CB and Metabo PE12-175)  and a 5/8 – inch for US / CA (09553)  made from an impact resistant synthetic nylon plate bonded to a 25mm thick layer of dense cellular foam. The highly flexible design allows for very easy transitioning from flat to contoured surfaces and the hook and loop backing material enables quick and easy pad changes.

Always use the recommended size backing plate for the sized pad you are using. Never use a backing plate that is larger than the foam pad or disc.

Always be willing to learn; because the more you learn, the more you’ll realize what you don’t know.
It is said that knowledge is power, with the caveat that it includes access to a reliable information sources. 

I would like to think that these articles become an asset to anyone who is new to detailing and to professional’s alike, as well as industry experts who seek to advance their knowledge.
I hope the article are informative. By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.

I would appreciate it if you would share these articles as it helps other detailers further their knowledge.

Questions and/ or constructive comments are always appreciated.


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