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JULY 2008

VOLUME 1, ISSUE 6

THE BASIC FUNDAMENTALS OF MASS FINISHING

CONTENTS

(PART II)

MASS FINISHING

1

INDUSTRY EVENTS

2

NEWS & NOTES

3

FROM THE FORUM

6

FINISHING SPOTLIGHT

9

THE LAST WORD

15

By: A.F. Kenton, President of Nova Finishing Systems I have not mentioned anything about burnishing media up to now. That is because, other than size and shape, there are no major differences or variations for this type of media; but size still determines weight, and that is a factor for selection. Non-abrasive shapes work parts the same way that abrasives do, but because there are no abrasives, there is little to no material removal. Any ma-

terial removed is due to metal fatigue caused by flexing. An exception to this is a sharp, spiral cut cylinder that is only made by one company, and is designed to actually remove material as long as the spiral ribs are still intact. Fine, inorganic materials can be added to steel for deburring, but it is not recommended because of cost factors, and because all steel media is heat treated to create a case hardening that is very thin. Besides steel and stainless steel metal

shaped media, porcelain is also used to accomplish the same task. The big difference between these two compositions is, once again, the weight factor. In fact, that is the main popularity of steel media - it is heavy, about 300 lbs per cubic foot versus about 100 lbs for porcelain and most other ceramic abrasives. Steel works relatively fast to produce a bright, shiny surface appearance; however, shine does not necessarily translate into smoothness. In addition to steel and

Inside This Issue: From the Forum:

Continued on page 4

Finishing Spotlight:

Finding a Solvent Solution

Dummying

that’s Right for

Tanks

you

(page 6)

(page 9)

(page 15)


Page 2

FINISHING TALK

INDUSTRY EVENTS 2008 July 14-18

August 18-19:

September 14-16:

MST Conferences

AESF Electroforming Course

Southern Metal Finishing

Orono, ME

Rochester, NY

Charleston, SC

www.mstconf.org

(202) 457-8401

surfacefinishingacademy.com

July 17-18

September 3-5:

September 15-16:

Composites World Expo

Powder Coating School

Schaumburg, IL

Charleston, SC

www.compositesworldexpo.com

surfacefinishingacademy.com

September 8-13:

September 18:

IMTS '08

Overview of UV Coatings Tech.

Chicago, IL

Virtual Learning Conference

www.imts.com

www.coatingstech.org

Lean & Green Summit Boulder, CO www.leanandgreensummit.com August 5-6: Powder Coating School Mystic, CT surfacefinishingacademy.com August 15:

September 10-11:

Bel-Air Finishing Workshop

Powder Coating Forum

North Kingston, RI www.belairfinishing.com

Cleveland, OH www.pcimag.com/pcforum

Have an upcoming event? Tell us about it at www.finishingtalk.com!


Page 3

VOLUME 1, ISSUE 6

NEWS & NOTES US & Canada Students pursuing careers in machining technology and manufacturing technology will have two new scholarships available through the Society of Manufacturing Engineers (SME) Education Foundation, thanks to funding from the Gene Haas Foundation. The Gene Haas Foundation Machining Technology Scholarship and Manufacturing Technology Scholarship will be awarded to qualifying students starting this summer. The Foundation made the scholarships possible through a $160,000 grant. Through its partnership with Project Lead the Way -- a nonprofit program that offers science, technology, engineering and math (STEM) curriculum in middle and high schools -- the SME Education Foundation will have the opportunity to draw from a national network of students participating in programs at more than 3,000 schools. This scholarship is specifically designated for students interested in coursework focused on machine operation & maintenance. For more info visit http:// www.sme.org/foundation and http://www.pltw.org. Indianapolis, IN On-line registration for COATING 2008, the international conference and trade show for the end users of industrial coatings, is now available on the show website: Fowww.thecoatingshow.com. cusing on today’s “hot topics,” COATING 2008, September 23 – 25, will bring you the latest on green technologies, energy efficiency, cost reduction and quality improvement in both its conference sessions and through its more than 150 exhibitors on the

show floor. The three-day conference will feature more than 30 sessions covering everything from liquid to powder coating, electrocoating to IR curing and pretreatment to porcelain enamel. Call Goyer Management with questions, or to have a registration brochure mailed to you, at 513-624-9988. Troy, MI BNP Media has announced that Finishing Today magazine will cease publishing effective after the July 2008 issue. Finishing Today magazine provided coatings professionals with the latest industry and product news, including advances in finishing materials and equipment, and current trends in environmental, legislative and business issues that impact finishing operations. “After exploring a full range of viable positionings, in a very crowded and competitive market, a very difficult decision was made to close down Finishing Today magazine”, stated John Schrei, Publishing Director of BNP Media, the largest family-owned b-to-b media company in the country. www.bnpmedia.com

On behalf of all of us here at Finishing Talk, we want to wish all

of our friends and the staff at Finishing Today the best, and we are sorry to see you go!! ~FT~

Plymouth Meeting, PA Federation of Societies for Coatings Technology (FSCT) President Yasmin Sayed-Sweet has announced that Joe Pontoski has resigned as FSCT Executive Director effective July 8, 2008. “Joe has been an outstanding leader for the FSCT especially during this past year as we finalized the

merger with the National Paint & Coatings Association (NPCA). His dedication, commitment and passion for the organization will be sorely missed and we wish him every success in the coming years.” Following Pontoski’s resignation, Pat Ziegler, Director of Communications, and the FSCT CEO will takeover Pontoski’s duties. For more information, please contact NPCA's Andy Doyle, (202) 462-6272, or www.coatingstech.org. Charlotte, NC With over 330 exhibitors and roughly 5,600 trade visitors, the American Coatings Show enjoyed a hugely successful premiere as the new highlight event of the US paint and coatings industry. Held from June 2-5, 2008 at the Charlotte Convention Center in NC, the combined trade show and conference exceeded all expectations right from the start. 332 exhibitors from 14 countries displayed a comprehensive range of products at over 69,000 sq. ft of space on all aspects of paint and coatings formulation. Companies from abroad accounted for 24 percent of the exhibitors, and in addition to the US, leading countries represented at the show included China, Germany, India, Canada, South Korea, and Great Britain. Featuring more than 70 presentations and other events as well as 750 attendees from 25 countries, the American Coatings Conference, which ran from June 2 to June 4, had more than twice the attendance originally expected. For information about the American Coatings Show & Conference, please visit www.americancoatings-show.com.


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FINISHING TALK

BASIC FUNDAMENTALS OF MASS FINISHING, CONT FROM PG 1...

porcelain, aluminum shaped materials, brass, zinc, and other metals are available in cut wire products and balls. Before we talk about the subject of organic materials, I want to mention a few things about the physical shape of media, because shapes are a factor in the processing of parts. Most shapes can fall into two categories; I have classified them as either bulldozers or steamrollers. Maybe rollers or scrapers would be better terminology. In either case, you have shapes that have a lot of diameter, or straight edge exposed in contact with the parts being worked. That means that the main function of the media shapes is either to roll

or crush, and the other to scrape. The shape, in mass, also affects the way the parts move within the equipment. That is, rounded shapes tend to move more and allow parts to seek greater depths than straight edge shapes. Geometric shapes tend to have a build up of resistance and force that removes material, while somewhat supporting parts higher up in the work mass. Both shapes work (provided the media can get into the work areas), but for smoothness I suggest rounded shapes, and for a lot of material removal I suggest geometric shapes.

worked. One of the more common suggestions is to select a shape that is larger than the holes in the part. If you have to go smaller, try not to select a media that will get stuck in the hole or is close to the hole diameters when you double or triple up the media in a bunch. Round or diameter media seems to get stuck more than the geometric shapes. Before selecting a media, get a couple of sample pieces, bunch them up, and just trying to force them into possible problem areas of the part or parts is one of the best ways to check out this lodging problem.

One of the biggest problems with either shape is the media getting stuck in the part to be

Why lodging occurs at all is an interesting story; however, the main reason is that the shape of


Page 5

VOLUME 1, ISSUE 6 the media is such that the center of gravity is usually right in the physical center of the shape. That means that the actual movement of the media is very stable and tends not to want to move at all, which is contrary to the purpose of mass finishing. That stability factor is usually overcome by the energy forces or action of the equipment, which sets this media into motion. However, if the media should find itself restricted, it usually just rattles around to a very small degree until it can’t move any more. Now, with all of this information about media shapes, there is one exception to all of the above. There is one shape, called either the V shaped cylinder, cylinder wedge, or tricylinder that looks and is made differently from almost all the other shapes. It is interesting because of its unusual appearance and behavior characteristics. This shape looks like a piece of pie or triangle in one direction and a cylinder in the other direction and it has its center of gravity on the outside edge. This latter statement means that the media shape is very unstable and very mobile. It exhibits the characteristics of both a roller ( it has an overall round shape) and a scraper ( two flats forming a very sharp wedge); therefore, it is usually the best general purpose shaped media available for all applications. Up to now, all of the media that we have discussed is run in what is called wet processes. That is,

these shapes are run with water and some chemical compound. All mass finishing systems are built with drain systems and provisions for liquid input. Because parts are made with cutting oils and pick up oils, greases, and dirt either by design for protection or by accident, chemicals are normally necessary to aid in the processing of the parts. Common practice is to use a water based biodegradable product in a diluted strength which can either be premixed or proportioned into the system. The pH of the product is important, but not the only factor. Inhibitors for protection and wetting agents are also desirable. The pH of waters is listed as 6.7 pH. Any number above water is considered basic, or caustic after 11, or acidic under the pH of water. Most chemical additives are interchangeable with either ferrous or non-ferrous parts, but most people use basic chemicals for ferrous parts and acidic products for non-ferrous and burnishing. At one time chemical compounds that produced a lot of suds were considered desirable for cleaning of the parts. However, it was determined that the suds actually slowed down the mechanical action of media in mass, causing longer time cycles. This same slow down of the media in mass can also be accomplished by just using too much water in the process, but it can also be accomplished by accident when drains become clogged or restricted due to debris. Even though chemicals are

used to assist cleaning and brightening metals, which is a removal process, an inhibitor in the product is usually desirable to protect parts against oxidation. Lastly, there are now some stronger chemical additives called accelerators that are used to help speed up the deburring process. Because the chemical does most of the work instead of the media, it is usually recommended the media contain no abrasive; thereby, there is cost savings of the media which does not have the same wear rates as abrasives. Dry organic media is the last category of media used in mass finishing systems and, as the name implies, this media is run dry. Anything that can be processed wet can be done with dry organic materials. The only problem is the longer cycle time due to the weight factor. The main advantage over wet processing of this media is in the deburring or polishing of small or flat parts. Both types of parts mentioned have a tendency to stick together due to water adhesion, and they also adhere to the sides of the equipment being used. This characteristic causes uneven surface finishing. The other advantage of dry processing is the elimination of water pollution controls or restrictions; but there is a trade off. Instead of water and waste disposal problems, there is some concern for dust particles that need either a cover or proper air ventilation. Dry organic media comes in the Continued on page 8...


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FINISHING TALK

FROM THE FORUM: DUMMYING TANKS BEFORE ELECTROPLATING Posted on March 14, 2008 Our column for July is a quick refresher on ’dummying’. Forum members Harold Evans, DustinGebhardt, and Finishing Market discuss the basics of dummy plating, and Finishing Market tosses in a few pictures. Feel free to add your thoughts to their ongoing discussion by visiting the forums at www.finishingtalk.com/ community and choosing the “Electroplating” forum. For more ‘From the Forum’ discussions, check out our monthly internet television show, Finishing Talk Live, where hosts Paul Fisher and Paul Skelton bring the boards to life! www.finishingtalklive.com

Harold Evans What is dummying tanks? How is it done? What happens to the anodes while dummying is going on? I will need to answer my student’s questions in the near future. Dustin Gebhardt Dummying is the common term for dummy plating, or using a scrap piece to plate, usually at lower or higher then normal current densities. If you were constantly nickel plating zinc, or copper, or brass parts, you would frequently dummy plate the bath at low current densities to PREFERENTIALLY remove the copper and zinc. Normally, the dummy has a large surface area, to maximize the amount of material removed. In my experience, a large piece of corrugated sheet metal is used with a current density close to 5ASF or lower. There are other uses for dummy plating. In a hex chrome bath, it can be used to remove chlo-

rides and activate the anodes. These dummies are usually very small to prevent the buildup of tri chrome. You can also perform a high-current density dummy plate to remove excess brightener. A separate dummy tank is usually one that is used to perform the dummying in. You can also do a continuous dummy, where you use a small tank with a separate rectifier, anodes, and dummy panel to perform the dummying continuously. Usually, you pump the solution into the tank, which is higher in elevation than the main tank. As the dummy tank fills, it overflows back into the main tank. Many platers use them in high-production shops to minimize down time. One thing to consider with the current price of nickel. While dummy plating targets a certain contaminant (usually), you are still plating a majority of your normal metal. That is to mean, in a nickel bath, you can try to dummy out zinc, but the majority of the deposit on the dummy panels will still be nickel. The zinc content will be higher than on a normal deposit, but it will still be mostly nickel. Finishing Market Hello Harold, As far as I know you can use almost any kind of compatible material to perform this dummy plating. You can see in the pictures that these Dummy Plates have been fabricated so as to maximize the surface area.


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VOLUME 1, ISSUE 6 Dustin Gebhardt Those type of panels tend to work very well. They can also be rotate 90 degrees to help remove shelf roughness in a pinch. The smaller you make the "shelves" the more uniform the surface area will be, and generally the more effective the panels will be. This will allow you to HCD dummy the bath without affecting the LCD

chemicals, and vice versa. With panels that have larger folds, you tend to build up a lot of plating on the corners and very little in the concave areas, making the panels less efficient.

Do you have something to add? Log on to the Finishing Talk forums today to join in on this discussion – or start a discussion of your own! www.finishingtalk.com/community 117 Westerly Hills Dr. Forest City, NC, 28043 Ph: (828) 245-1115 Fax: (828) 245-1216 Carolina Process Control provides the metal finishing industry with a single source solution for all their industrial waste water treatment system and component needs. We design, build and install turn-key waste treatment systems for pH neutralization, heavy metal removal, water recycling, zero discharge and other chemical processing applications.

www.carolinaprocesscontrol.com


Page 8

FINISHING TALK

BASICS OF MASS FINISHING - CONTINUED FROM PAGE 5

form of small random shaped particles of granules or sawdust fiber, which can either be used by itself, or in a two part form. The finer material is normally used with larger wood shapes in a 5:1 mix of shapes to particles. The reason for this two part mix is that there is hardly any weight to the organic materials. They weigh only between 20 to 35 pounds per cubic foot; therefore, bulk or the wood shapes are desirable for adding weight to the process to improve cycle times. Other, non-abrasive heavier media can be added for bulk and produce good results. When any dry organic materials are combined or mixed with polishing rouge, they are excellent in producing almost hand buffed looking, polished parts. When combined with inorganic materials, they are very effective as abrasives. Because of the weight factor, the deburring and polishing qualities of these blended mixes still take a longer time to produce the same results as wet process media, but usually the surface finish is of superior, finer and cleaner quality. Within the last 5 years, a new form of dry organic materials has been developed that looks something like plastic media. There is now a patented composite process that takes inorganic and dry organic materials and makes them into shapes, which are used in dry processing. These shapes are made in such a way that they can actu-

ally have more inorganic abrasives than the dry organic material, but they are still used dry. Also because of the increased weight of this preform, it is now competitive to wet processing media in time cycles and without the problems associated with water. According to the manufacturer, this new material will outlast all other abrasive media by 5 to 20%. The advantages offered by this dry media and applications normally warrant the extra high cost of this new product. As you can tell, there are three main factors that control deburring or burnish of parts in a mass finishing system, they are: the equipment, the media, and either the liquid or additive to the operation. Surface finishing on parts can be repeated over and over again if these elements are constant. Any variation of one of these elements will change the results or time cycle. Basically, once a machine system is selected you are locked into some limitations of that machine system. Therefore, that means that media selection is probably the most important variable in the processing of parts, and effects the costs of operation and the surface finish the most. Hopefully, with some of these basic fundamentals down, you can better achieve the processing results you are looking for. If you do, however, need help or further information, you can contact A.F. Kenton at Nova Finishing Systems Inc. or

call 1-800-444-4159. [1] NOTE: The author has written a book which completely classifies all methods of deburring and/or surface finishing into 5 energy classes of equipment and then rates them with a numbering system based upon how they perform and what they are capable of achieving. The book is entitled Understanding

Deburring and Mass Finishing Systems.

[2] NOTE: Although zirconia is listed here, the more common fast cut media is made with aluminum oxide and has very similar characteristics and normally costs less.

Nova Finishing Systems Inc., manufactures small, heavy-duty bowl finishers that stack up to most of the big equipment on the market, but cost much less. Nova series vibratory equipment also comes with the same warranties of the larger machines. For more information on this equipment line, contact: Nova Finishing PO Box 185, Hatboro, PA 19040 215-942-4474 800-444-4159 Fax 215-953-1342 novafinish@earthlink.net

You can read Part I of this article by checking out the June issue on our website: www.finishingtalk.com/publication

~FT~


Page 9

VOLUME 1, ISSUE 6 FINISHING SPOTLIGHT:

T

he widely discussed and anticipated Sur/Fin 2008 conference and tradeshow culminated on June 18th, after three days of industry discussion, education, exhibition, and camaraderie. The conference, put on by the National Association for Surface Finishing (NASF), showcased more than 150 exhibitors and attracted more than a thousand

finishers and general attendees. Special events this year included the NASF’s Indianapolis Branch Reception, held at Jillian’s restaurant and game room just a few blocks away from the Indianapolis Convention Center. An unanticipated number of people turned up for food and fun – but the more, the merrier! Finishing Talk Live’s co-hosts Paul Fisher

and Paul Skelton filmed a live showing of their IPTV show, with special guest Michael Siegmund of MacDermid. They put on a great show, despite difficulty competing at times with the mingling sounds of onlookers, numerous pool games, and even a bowling alley. Busloads pulled up at the Indianapolis Motor Speedway on

Continued on next page...


Page 10

FINISHING TALK Tuesday night, for a private Industry Night Party. The Hall of Fame museum opened its doors to the hoards of eager party goers, and presented its dazzling array of antique race cars and motorcycles, speedway memorabilia, and more, to the delight of all in attendance. There was a delicious catered buffet spread out in the Pavilion, and the evening was highlighted by small bus tours of the Speedway itself, giving riders the opportunity to get off and take photos at the finish line (which is composed of bricks from the original track surface!). Educational opportunities consisted of a wide array of symposiums and training courses. Featured sessions were those that were covered during the Automotive Symposium, Airline/ Aerospace Symposium, and the Surface Finishing Research technical conference. Within these broader fields were classes, lectures, and workshops


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VOLUME 1, ISSUE 6 with themes such as NanoTechnology, Organic Finishing, Light Metal Finishing, Conversion Coatings, Electroless Deposition, Management Outlook, Process & Environmental, and more. This year’s featured speaker, Dr. Robert Schnorbus of J.D. Power, gave those in attendance an in-depth look into the impact of global sourcing, supplier concerns, and other related regional and global issues affecting the automotive industry. The NASF member pavilion was a popular spot for casual socializing, catching up with phone calls or e-mail, taking a quick break from all the walking - I think I even spied a few people attempting to catch up on their sleep after a night out in Indy - in addition to a con-

venient location to learn more about the NASF and membership benefits. Planning for SUR/FIN 2009 in Louisville, Kentucky is already underway (that means a

shorter drive for those of us at Finishing Talk next year!). You can find additional information about SUR/FIN, the NASF, educational opportunities and more by visiting www.nasf.org.


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FINISHING TALK

EPA AMENDS HAZARDOUS WASTE LISTING

E

ffective July 7, 2008, the Environmental Protection Agency (EPA) will amend the list of hazardous wastes from non-specific sources (called F-wastes) by modifying the scope of the EPA Hazardous Waste No. F019. Specifically, the agency plans to exempt wastewater treatment sludges from zinc phosphating, when such phosphating is used in the motor vehicle manufacturing process— provided that the wastes are not placed outside on the land prior to shipment to a landfill for disposal, and the wastes are placed in landfill units that are subject to or meet the specified landfill design criteria.

codes 336111 and 336112, respectively). Other motor vehicle manufacturing industries (e.g., heavy-duty truck or motor home manufacturing) are not affected by this rule. Entities potentially affected by this action are at least seven current F019 generators within these two industries, consisting of four auto and three light truck/utility vehicle plants, and up to 42 other facilities in these two industries that may begin applying aluminum parts and could potentially generate regulated F019 waste without this final rule (based on 2005 Biennial Report data). Note: This action might also affect the 19 auto and light truck plants with prior F019 delistings issued between 1997 and 2007, because this action could supplant their delisting status and conditions, depending upon the extent of state government voluntary adoption of this final rule [1].

Note: This final action on the F019 listing does not affect any other wastewater treatment sludges either from the chemical conversion coating of aluminum or from other industrial sources. Additionally, this rule amends the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) list of Hazardous Substances and Reportable Quantities so that the F019 listing description The EPA has established a docket for this action under is consistent with the amendment to F019 under regula- Docket ID No. EPA-HQ-RCRA-2006-0984. All documents tions for hazardous wastes from non-specific sources. in the docket are listed at the www.regulations.gov website. For information on specific aspects of the rule, conThis final rule could directly affect businesses that genertact James Michael of the Office of Solid Waste (5304P), ate certain wastes from the manufacturing of motor vehiU.S. Environmental Protection Agency, 1200 Pennsylvania cles in the (1) automobile manufacturing industry and (2) Avenue, NW, Washington, DC 20460, via e-mail at light truck/utility vehicle manufacturing industry (NAICS michael.james@epa.gov, or by phone at (703) 308-8610.


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VOLUME 1, ISSUE 6

PRODUCTS FINISHING INTEGRATES FINISHING TALK FORUMS

P

roducts Finishing magazine recently unveiled the product of its collaboration with the popular metal finishing community and forum, Finishing Talk. Over the past two years, Finishing Talk has exploded onto the industry scene as a cutting edge online community, forum, newsletter, and marketing company for metal finishing professionals. With a rapidly growing membership and an active community forum, Finishing Talk was an appealing choice for a cooperative web endeavor with Products Finishing.

"The people that use PFOnline will now have another resource that harnesses the power of the Internet," says Products Finishing Publisher Don Kline. "They can now get their questions answered by an active community that includes top finishing professionals from all over the world. PF is excited to be working with Finishing Talk."

Products Finishing magazine is an industry renowned

publication with more than 40,000 subscribers - the largest circulation in the finishing industry. The magazine's Web site, www.pfonline.com, is an established and respected resource for metal finishers. It contains a large database of industry suppliers and products, extensive archives of past issues, an inter-

active clinic touting prominent consultants and educators, and more. The addition of the Finishing Talk Forums to the site will be an added benefit, possibly drawing a new generation of finishers into the Web site. The collaboration will be a big boost for the up and coming Finishing Talk community, as well. Though Finishing Talk will remain an independent Web site after the integration, the forums will also be accessible through Products Finishing's site. This will serve to increase traffic on the forums and bring added exposure to other products and services that Finishing Talk currently offers. "We are pleased to have this opportunity to expand our membership and provide a place for finishers to discuss issues of importance to them, within a likeminded community. With a new gateway to the forums, via PF online, more of these individuals will benefit from this great service - and it's free!" commented Paul Fisher, Administrator of FinishingTalk.com, and publisher of the Finishing Talk newsletter (yep, that’s us!). Visit the new portal at: www.pfonline.com/forums.

FINISHING TALK’S ARTICLE CONTEST EXTENDED Starting on June 1st 2008 and ending August 31st, Finishing Talk will be holding an article contest. Articles must be industry-related (powder coating, painting, electroplating, anodizing, etc…), and no longer than 2,000 words. The winning articles will be published in upcoming issues of Finishing Talk. Articles will be judged on relevance to the industry, professionalism, accuracy, organization of ideas, originality and overall flow. Accompanying images may be submitted along with the article or editorial. We are open to a variety of styles - from the purely technical to pure opinion - so go ahead and submit what you’ve got! Articles may have been published previously, but the author may only submit a pre-published article if they hold the rights to it and have the authority to do so. The 1st place prize will be 6 months of free banner ads for your company on the Finishing Talk website. 2nd place receives 3 months of banner ads, and 3rd place will receive a banner ad for 1 month. You may submit your article digitally either through the Finishing Talk forums at www.finishingtalk.com/community and click on ‘article submissions’, or by e-mail to Anna Levitsky, anna@finishingtalk.com. You may also mail a hard copy to PO Box 349, Rutherfordton, NC 28139. Good luck!


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FINISHING TALK

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Page 15

THE LAST WORD FINDING A SOLVENT SOLUTION THAT’S RIGHT FOR YOU

I

n the finishing industry, solvents are primarily used for parts cleaning. Many of these, such as trichloroethalene (TCE), can be advantageous in that they are fast acting and quick to evaporate, which minimizes drying time. On the downside, these same solvents can be extremely toxic, carrying the health risks of liver and kidney damage, neurological disorders, and even cancer. They are also culprits when it comes to soil and water contamination, and other areas of environmental degradation. So what is a finisher to do? The good news is that an increasing number of alternatives to traditional solvents are appearing across the spectrum, making it easier to safeguard your worker’s health and the health of your community.

Where do I begin? The mounting government crack down on non-reusable or nonrecyclable solvents is a good enough reason in and of itself to start rethinking and minimizing the use of solvents in your operation. But where to start? The easiest first step is the first step of any ‘sustainable’ approach; that being to reduce wherever possible. If you can use less of any hazardous substance, then make sure to do so. Once you’ve filtered out what can be reduced, it’s time to focus on what can be replaced. It is important to first go through and identify the uses and volumes of solvents you have in your facility, which will allow you to determine which ones should and can be substituted with something else. Examine your current stock of solvents, keeping an eye out for those containing chemicals or

compounds that may soon be phased out. You should ask yourself the following questions:

1. What are the parts that need to be cleaned?

2. What contaminants are being removed during the cleaning process?

3. Why are these parts being cleaned? (In some instances, it may turn out to be an unnecessary step and expenditure) 4. How can I stop contamination at its source, prior to the need for cleaning? 5. To what degree must the parts be cleaned? After you have answered these questions, you can apply this knowledge to your quest to find the most functional and effective alternatives. Alternatives to Consider There are several popular and cleaner alternatives to solvent cleaners available to finishers today. One of the most popular is water-based cleaning, also known as Aqueous cleaning. Various processes to remove contaminants include the use of acidic and/or alkaline aqueous solutions, as well as immersion, pressure spray and ultrasonics. A compromise between solvent use and aqueous cleaners is what is known as a Semi-Aqueous cleaner: a semistable mixture of water and solvents (or ‘emulsions’). These are often used for removing waxes, heavy greases, tar and baked-on organic materials. Carbon Dioxide (CO2) Blasting is another option that consists of two main technologies: CO2 Pellets and CO2 Snow. The Pellets combine solid CO2 and a gas to strip paints

BY ANNA LEVITSKY

and to remove grease and oil, whereas the CO2 Snow relies on flakes of frozen CO2 to clean surfaces. Another cleaning alternative is Supercritical Fluids. Lacking in surface tension, these fluids can quickly and thoroughly dissolve contaminants, and are easy to remove. Yet another option is Media Blasting, which is a process that uses abrasive media (such as sand, glass beads, and more recently plastic particles) dispersed at high pressure against a surface to remove contaminants. A great resource for finding comparable solvent replacements is the Toxics Use Reduction Institute’s (TURI) Surface Solutions Laboratory, (www.cleanersolutions.org). Here you will find the easy to navigate ‘Replace a Solvent’ page, allowing you to search for alternatives based on the solvent you wish to investigate, and then narrowing down your results by contaminant, substrate, and even equipment type. TURI is an especially helpful resource, due in large part to the fact that they actually test these alternatives, and rate them according to their effectiveness in application. Another good resource is the Integrated Solvent Substitution Data System (ISSDS) at http://es.epa.gov/issds. Always consider the potential environmental impacts, health and safety concerns, solvency, flammability, cost, and stability of a solvent before choosing the right one(s) for your needs. Since there is no single ‘miracle solvent’ out there, be sure to evaluate each option thoroughly in order to achieve the best results, while causing the least negative impact to your workers, your community, and your environment.


PRST/STD US Postage Paid Rutherfordton, NC Permit # 154

PO Box 349 Rutherfordton, NC 28139

July 2008 Anna Levitsky, Editor Phone: 704-995-2263 anna@finishingtalk.com

www.FinishingTalk.com See what the industry is talking about!

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July 2008 Issue of Finishing Talk