UWM Silicone Elastomer Course a HUGE success!!
| |"You have an excellent team of instructors"
| |"Best way to apply and see firsthand all the theories explained. Good system & administration of activities"
| |"The shop tour was amazing. It was very educational"
| |"My questions was answered and more"
| |"Very informative and eye opening. If I had previous experience would have known how to use information presented & opportunity better"
| |"The trip to the mold shop was very beneficial, esp the trouble shooting with John
| |Everything was very helpful"
| |"The combination of presentations provided an overlapping perspective/understanding of the LSR process from each piece of the process."
How to Mold Liquid Silicone Rubber Successfully
Posted in Molding Services by bmichaels on November 21, 2014
Communication and cooperation among partners are critical for optimizing LSR molding results.
In a medical device molding project involving liquid silicone rubber (LSR), the molder, the mold builder, and the molding press manufacturer can dramatically affect the success of the project by communicating with one another clearly and cooperating to meet customer requirements. Often involving close tolerances and precise control of critical characteristics, molding LSR-based medical devices can be especially demanding.
|Example of a component made from optically clear liquid silicone rubber.|
All three partners need to share not only detailed specifications with one another but also their experiences in molding LSR. Even when all three parties are familiar with LSR molding techniques, each has unique and intimate knowledge of a given specialty––molding, mold building and press performance. In addition, each acts as a knowledgeable consultant to the others, thus resulting in a stronger partnership than the traditional arrangement in which a mold builder and a press manufacturer simply serve as vendors to the molder.
The communication phase requires continuous discussions that should begin before the molder responds to a request for quotation (RFQ). While these discussions may initially involve primarily the molder and mold builder so that they can design a new mold, the participation of the press manufacturer is also essential for sharing expertise about the functional interaction between the mold and press. While a new molding press is not required for each new project, the press manufacturer’s input is vital for advising which of the molder’s existing presses will produce the highest-quality result most efficiently.
This interaction ensures that the partners will have agreed on the pricing and will have synchronized production and delivery schedules before the project begins. Preliminary information gathering and planning is an essential investment in the success of the project. Always costly and time-consuming, unforeseen obstacles during production inevitably reduce the finished product’s time to market. By sharing their own unique expertise, the partners can forge a tight team that ultimately works to the benefit of the OEM and the customer who uses the medical device.
LSR Molding Partnership
The Molder’s Perspective. In most cases, it is the molder that receives the RFQ from the customer, responds to the RFQ, initiates the project, and produces the part when the quote is accepted. Molders that are experienced with the intricacies and challenges of LSR molding should immediately reach out to their mold making partner and press manufacturer, both of whom should be equally experienced to consult about the project.
Next, the molder should provide the mold builder with those project specifications that will affect the mold’s performance: the annual production volumes of the finished piece; the type of molding machine to be used—whether vertical or horizontal; the required mold surface finish; sealing surfaces, if any; secondary operations that can affect the process; and whether a fully automatic cold runner mold will be needed.
|Two halves of an assembly composed of a two-shot thermoplastic and a tactile silicone pushbutton switch.|
The more detailed the specifications, the better able the mold builder will be to assess the required mold features. To provide this level of detail, a mold specification checklist such as that shown in Figure 1 can be employed for each mold RFQ. This checklist can include such specifics as the mold type; the type of mold base steel; details about sprues, runners and gating; ejection requirements; cavity qualities; cores; special features; and tool actions.
After digesting these details, the mold maker may well respond with alternative suggestions based on experience in order to achieve a more efficient molding process or a higher-quality result. For example, the mold maker may recommend the use of two 16-cavity molds instead of one 32-cavity mold or suggest the use of a different mold base steel.
At the same time, the molder should consult with the molding machine manufacturer about which of the molder’s existing presses are most effective for the project at hand. This discussion should also address whether a specific press must be modified or have such features as heating zones, vacuum, or a cold runner to suit the current project. The experience of the press manufacturer is invaluable for assessing whether such modifications are necessary.
In its ongoing relationship with the molder, the press manufacturer will have already recommended presses that provide both additional capacity and additional flexibility to the molder’s production capacity. Drawing on knowledge of the press itself and experience with other customers that have used it, the press manufacturer knows what a particular piece of equipment can do.
This is where the value of a partnership comes into play: The molder, mold maker, and machine manufacturer engage in a three-way conversation, exchanging ideas and experiences that result in the best options for the project. At this point, the molder can submit a proposal to the customer with confidence that it is based on solid experience.
|Petri dish with a 0.004-in. wall of transparent silicone bonded to a green wall of polycarbonate.|
The Mold Maker’s Perspective. Molding LSR is completely different from molding plastics. Mold makers familiar with creating molds for LSR applications point out that molders with experience in plastic molding but new to LSR molding enter unfamiliar and risky waters, often without realizing it. Molders of plastic materials tend to assume that years of experience with plastics translate directly to LSR. However, the opposite is true. Such molders should forget everything they know.
LSR molds must be of very high quality and must be machined to extremely precise specifications. In addition, they make demands on the molding press that plastic molds do not. As a result, an LSR mold can be significantly more expensive than a similar-sized plastic mold, shocking molders new to LSR applications.
The Press Manufacturer’s Perspective. The other critical tool in the molding process, the molding press, must work with the final version of the mold and meet such project demands as the daily production volume, the total number of parts to be molded, and the product life cycle. In addition, an LSR press must contain more heating zones than a plastic press and must include a vacuum system. The discussion between the molder and the press manufacturer often begins by evaluating whether an existing press will work or whether a new one will be required.
When designing the mold, other factors determine the best press for the project, including the shot size and number of mold cavities, the material specifications, and the part design. Because the materials used to mold LSR-based medical device components and the designs themselves are at the high end of the technology curve, the press and the mold must work together precisely and efficiently.
Molds are built for a single molding project, although the project may continue over several years. Molding presses, on the other hand, involve significant investments that must be amortized over many years and many projects. Thus, while a press must be able to work efficiently with a mold for the duration of the project at hand, it must also be able to work with other molds and other projects. To achieve the optimal interaction between the molds and presses over the long term, the press maker should seek input from the molder about the products it may manufacture in the future and from the mold maker about the most suitable presses for such applications.
A Coordinated Effort
Flexible, chemically stable, durable, and biocompatible, liquid silicone rubber offers unique properties to medical device manufacturers. Because of these valuable properties, the material will continue to grow in popularity, especially as medical devices shrink and become more complex. Moreover, this trend will proceed apace as manufacturers produce more and more products for the home healthcare market. As a result, more molders, mold makers, and press manufacturers will become involved in LSR molding. Thus, it is essential that they openly exchange information with vendors who have learned from experience that LSR is a key to efficient, cost-effective, and successful molding.
Jim Ritzema is director of operations and technology of Northbrook, IL–based Rogan Corp. Reach him firstname.lastname@example.org
Geri Anderson is marketing director of Brea, CA–based M.R. Mold and Engineering Inc. Reach her email@example.com
The Collectors Will Love This Exhibit at NPE
M.R. Mold & Engineering Corp
., which has earned its bona fides as a producer of molds for liquid silicone rubber (LSR), is raising its profile for making plastic injection molds with a tool running at NPE2015
that involves an eight-company partnership.
And it might be one of the most fun of the “give-away” demonstrations at the Big Show, which will be held next month in Orlando, Florida.
A plastic injection mold built in partnership with Craftsman Tool & Mold (S16059), Progressive Components (W4345) and Mastip, Inc. (W8191) will be running in Wexco Corp.’s booth (W1903).
One of the interesting aspects of the project is a large living hinge molded into a 3-in x 6 ½-in survival box made with a PolyOne high-density polyethylene (HDPE) compound. The PolyOne material will be running in a Toshiba Machine (W1763) molding machine with a Yushin America, Inc. (W763) robot.
The box can be filled by visiting three other booths. Toshiba is doing a mini flashlight; M.R. Mold (W1873) is doing a first aid kit and Mastip is doing a snack pack. Others may still jump in.
And M.R. Mold will showcase an LSR micro mold in Wittmann Battenfeld’s (W2743) MicroPower 15/10 B6P using a Graco/Fluid Automation 622 miniature meter mix system with 20 oz cartridges for shot sizes smaller than 40ccs.
In 1985, Rick Finnie opened M.R. Mold & Engineering in Brea, California, with one employee. In 2005, the company opened a 4,000 sf Technology Center with four company-owned molding machines, allowing mold testing before shipment and turnkey projects. A 110-ton Arburg 470A horizontal molding machine equipped for thermoplastic and silicone was added recently.
CALIFORNIA MOLD MAKER ADDS NEW PRESS
By Roger Renstrom
M.R. Mold & Engineering Corp. of Brea, Calif., has upgraded its injection molding capability to enhance testing and sampling of customer molds prior to shipment.
The firm took delivery Sept. 4 of a 110-ton Arburg 470A horizontal press that is equipped for thermoplastic and silicone processing and is suitable for short-run production volumes. The hydraulic unit replaces an existing 110-ton electric.
The new Arburg has a 30mm liquid-silicone-rubber barrel and screw and a 35mm plastic barrel and screw, extra heating zones, valve gate controls for cold runner systems, vacuum and a robotic interface. Arburg will train the press operators, and M.R. Mold plans to send two technicians for training in scientific molding processes.
Four other hydraulic presses include a 70-ton Arburg Allrounder 370S, a 100-ton tiebarless Engel and two 55-ton Engels.
M.R. Mold is shopping for a laser engraver to meet customer needs for cavity identification and logo imprints, functions that are now outsourced. The device would engrave mold components, a task M.R. Mold does now on computer-numerical-control milling machines.
In-house use of an engraver will free up machine time.
M.R. Mold partners with the Santa Ana, Calif.-based group Science@OC to advance the federal STEM education strategic plan encouraging students in science, technology, engineering and mathematics disciplines.
“We understand the importance of American manufacturing and the lack of education in our society,” said Rick Finnie, M.R. Mold president. “Manufacturing is no longer a ‘dirty’ business. It is our hope to provide shop tours for students to show them from ‘art to part’ how the process works, tying in why math and science are important.”
Finnie aims to promote scientific literacy among Orange County students, make presentations, attend job fairs and bring industry colleagues into the effort.
The firm has developed another proprietary pneumatic stuffer box for higher-volume sampling, short runs or micro molding where a small amount of material is needed. Typical use of LSR in production requires a pumping unit to mix components prior to injection into the mold.
The stuffer box injects a small dose of pre-mixed material into the barrel of a molding machine and eliminates the need to repetitively clean a pumping unit. The new high-volume version has a volume of 78 cubic inches or 3.1 pounds of pre-mixed material, while the earlier low-volume model has a volume of 27 cubic inches or 1.1 pounds of material.
M.R. Mold has hired six persons since April and now employs 30 including seven mold makers and five CNC specialists. The firm seeks more CNC and design talent.
M.R. Mold envisions a 20-percent increase in sales for 2014 vs. its actual 2013 results.
Rogan Adds M.R. Mold Cold Deck System to its Vertical LSR Molding Machine
Northbrook, IL, May 2014 - Rogan Corporation, known for its true two-shot, liquid silicone rubber, and insert molding, has purchased and added a new cold deck system to its vertical Sodick Plustech Liquid Silicone Rubber (LSR) molding machine. The cold deck will reduce the volume of LSR material used during molding by eliminating the sprue and runner waste that occurs with traditional silicone injection molding. The result is a reduction in part costs, material savings, reduced cycle times, and increased equipment utilization. In addition, Rogan customers also experience a significant tooling savings benefit.
“Given the complexity of the LSR parts that we produce,” states Jim Ritzema, Rogan’s Director of Operations, “customers can realize tooling savings of between $25,000 - $50,000, depending on the size of the mold, by not having to purchase a cold deck system for their custom tooling.”
The Rogan cold deck is a two-drop system. The vertical LSR molding machine has a rotary platen on the core side, so there are two bottom halves and one top half. When molding a part, the operator is able to de-mold parts and/or load inserts into the B half while the molding cycle is taking place. The result is faster molding cycles and maximum operator efficiency.
Rogan currently has similar cold deck technology in place with its horizontal LSR molding machines. Adding this system to its vertical LSR molding machine provides the company with additional capacity to take advantage of better utilization of equipment.
“This new cold deck system will further reduce material costs for our LSR molding customers,” says Ritzema. “Unlike waste from thermoplastic molding, which can often be re-ground and re-processed, waste from LSR molding is a loss, and can be a major cost factor, since LSR is a premium material. This is especially true when molding small parts, where typically the runner can often be as much as five times the size of the individual part itself.”
Rogan purchased the cold deck system from M.R. Mold and Engineering. The system is a split plate design that facilitates ease of cleaning and maintenance. This design also allows for quick material and color changes.
Using the new cold deck system, Rogan can efficiently mold small parts, as well as larger parts up to 12 square inches.
Molding 2015 - Call for Papers
25th International Conference & Exhibit
June 16-18, 2015
Donald E. Stephens Convention Center, Rosemont, IL
ABOUT THE CONFERENCE
The 25th International Conference & Exhibit Molding 2015 is a unique event organized by a volunteer committee of all branches of the industry – molders, moldmakers, materials suppliers, and the trade press. The conference will focus on important innovations in manufacturing technologies of consumers and industrial products. Industry leaders will present the latest developments in various injection molding processes, hardware and controls with special emphasis on adding value to your business. These conferences are widely recognized as the most important forum for technical information and business connections.
Adding Value: Automations/Assembly/Packaging LSR Molding
Molding of Integrated Electronic components
Abstracts (WORD) should be e-mailed to Conference Chairman firstname.lastname@example.org, or to any member of the organizing committee. Abstracts Deadlines: October 17, 2014
M.R. Mold Exhibits at Southern California SPE's Western Plastic Trade Fair
July 10, 2014
Western Plastic Trade Fair
Half day seminars and supplier exhibitions.
Three must see seminars for the plastics professional along with exhibits from the best suppliers to the Southern California plastic community. Tasty German Dinner along with our famous raffle.
August 14, 2014
Seminar 1: 1:15-2:00PM
"Material Selection - 8 Questions To Ask"
Robert P. Frey,
Lead Technical Development Engineer
If you've ever wondered how to make sure you get the information needed to assist your customer in selecting the right material for a job, these 8 questions...actually more like 8 subjects to discuss... will likely bring up a lot more questions, but will also get the discussion started and will likely make your customer thing more about his application, and what it really needs. Included are concerns regarding the chemical, thermal, mechanical and regulatory environment, as well as a few other topics.
Bob has 40 years of experience in the plastics industry, starting with production jobs at Dow Chemical, then moving to GE Plastics for 7 years of tech support work in the NORYL®, XENOY® and VALOX® resin businesses. Bob left GE Plastics and spent 7 years self-employed as a consultant, focusing mostly on computerized flow analyses. During those years, he worked with a broad variety of thermoplastics, both engineering and commodity. In 1993, Bob re-joined the GE family as the Technical Service Engineer for Polymerland, and stayed with GEPlastics until shortly after the buyout by Sabic. Finding that working for a single resin supplier was "too constricting", Bob moved to PolyOne Distribution in 2008. This position at PolyOne Distribution includes responsibilities for processing, design, material selection, failure analyses, and education (both internal and external). Bob has a BSME degree from Case Western Reserve University, in Cleveland, Ohio. In his current position, Bob has responsibility to support customers in the 14 western United States as well as western Canada and the northern portions of Mexico.
Seminar 2: 2:15-3:00 PM
Silveys' Plastic Consulting
Within the injection molding process there are many areas of shear which have an effect both on the plastics in the form of heat impute, to that which is caused by all the restricted areas in the machine, nozzle, and mold feed system. Understanding the areas and the possible effects can lead to an understanding of what is controllable and easily interchanged from machine to machine as the tool moves yielding another universal setup point to consider.
Though short the presentation shall cover:
Screw RPM vs surface speed
Temperature raise in nozzles
Shear and flowability
Gate design and effect of injection speeds
Steven L Silvey has many years in the plastic industry with experience in most of the major processing methods. He spent the first 16 years of his career in the custom molding, blow molding, compression and ophthalmic molding/casting businesses with duties ranging from maintenance, set-up/molder, R&D engineer, Tech Service Manager, to Engineering Manager at various companies. In addition he also filled in at Laney College, teaching mold design and part design in the evenings. Steven than worked at General Polymers/ Ashland for 15 years, as their technical services engineer covering the Western region of the United States, Mexico, and Western Canada. In 2003 Steven started applying his knowledge as consultant as owner of Silveys' Plastic Consulting. In this capacity he continues to provide solutions and education to those in the plastic part manufacturing area
He is a graduate of California State University Chico. A Senior Member of SPE, Certified Instructor for RJG Systematic I training course, Certified Plastic Technologist and member at large of Epsilon Pi Tau.
Optimizing Pack & Hold times In Hot Runner Molds
For cold runner molds, the pack and hold times are optimized by conducting a gate freeze study (or gate seal study) where the part weight is recorded as a function of the pack and hold times. When the gate freezes the part weight remains constant with increasing pack and hold times. A second or so is added to the lowest value of time where the part weight stays constant and this number is taken as the total time for the setting of the pack and hold times. However, in hot runner systems or in valve gated systems the gate area always has molten plastic and therefore the above method does not produce acceptable results. A method for optimizing this value in hot runner systems or valve gated systems is proposed based on the Cosmetic and Dimensional Process Window. Experimental results will be shown.
Suhas Kulkarni is the President of FIMMTECH, a consulting firm that specializes in services related to injection molding. He earned his Masters in Plastics Engineering from the University of Massachusetts, Lowell and a Bachelors in Polymer Engineering from the University of Poona, India. He has 22 years of experience as a process engineer. His main area of expertise is Scientific Processing for Injection Molding. He conducts regular training seminars in Injection Molding and has developed a custom software called Nautilus, that aids the complete process development routine to production release. He is a contract faculty at UMASS Lowell and has given numerous presentations and written several articles. He is also an author of the book 'Robust Process Development and Scientific Molding' published by Hanser Publications in 2010.
Jim Albert, General Manager, Retires
Jim Albert, the General Manager of M.R. Mold & Engineering Corp is pleased to announce his retirement as of June 27, 2014. Him has been an important part of M.R. Mold for the past 22 years. His knowledge of both plastics and silicone has enabled M.R. Mold to grow into the industry leader it is today.
Effective immediately, all RFQs, inquiries and correspondence should be sent to Rick Finnie, Brian Geisel, Ray Shapland or Don Marple at their respective email addresses.
Join the M.R. Mold team in wishing Jim, and his wife Dawn, a very relaxing and enjoyable retirement!!
M.R. Mold Boasts Record Month in June 2014
June 2014 will be a month that goes down in history! In the 29 years M.R. Mold has been in business, business has never been so good. Record sales were recorded last month.
To express his appreciation for his employees hard work and dedication to meet customer's needs and deadlines, Rick Finnie, president, pulled out the grille and barbecued filet mignon for his 30 employees. Served with baked potatoes and Brian Geisel's homemade baked beans, the lunch was a resounding success!
The addition of 6 new employees, ranging from apprentice to management, in the past two months has provided M.R. Mold with the skill and expertise needed to build, sample and ship molds ON TIME!!
"We have no reason to believe it will slow down anytime soon," states Rick Finnie. "Our customers are telling us the work will continue to be awarded to M.R. Mold."
BEWARE of CHINA! Protect your website!
M.R. Mold & Engineering Corp., Brea, CA, recently fell victim to a different type of cyber crime: website piracy. While surfing the internet for images, M.R. Mold Owner Rick Finnie came across an image that he recognized as his own, and hovered over the image with his mouse to track the source. To his surprise, M.R. Mold’s website did not appear but instead, a company from China by the name of Mold Sourcing China. The website was an exact copy of M.R. Mold’s site, from categories and tabs to all verbiage and images. M.R. Mold’s website had been pirated – copied to the T. Taking immediate action, M.R. Mold contacted AMBA’s partner law firm Ice Miller to see what could be done. According to M.R. Mold Marketing Director Geri Anderson, its website administrator was a great help and immediately identified the host of the pirated website. “Ice Miller sent out a letter to the host company to cease and desist, accompanied by a 40-page document proving the website was pirated,” said Anderson. “It was a long, arduous process putting together the documentation, but it was necessary to prove the theft.” It also cost the company almost $8,000 to claim what was their own. The process took about a month and on January 10, 2014, the pirated site was taken down. Unfortunately, on January 13, 2014, just three days later, the site reappeared using a new host, and the process started all over again. “We went after the hosts instead of the Chinese company because the hosts were in the US and provided a route that was much easier and quicker,” said Anderson. “Going after the registrar would have taken too long and cost too much money.” Today, M.R. Mold continues its struggle, as the stolen site still contains two categories copied off of its website. To help combat future theft, M.R. Mold recommends taking the following precautions:
- Watermark all images with company name and/or website. These watermarks cannot be removed and help to protect your property.
- Register your contact information with Google. Google then checks content information and the author to ensure its validity. If Google finds it is not valid, it penalizes the fake author via Google rankings. This doesn't prevent others from using your content, but it is a deterrent.
- Conduct periodic searches through your web browser to ensure the integrity of your website.
Get Free Early Bird Passes to NPE 2015
|...Gets the Free Pass!|
Yes, we know NPE2015 is a year away, but already, great things are happening…so, register today for the world’s most influential plastics trade show and conference, and get unparalleled access to all of the people, equipment, technology and information shaping the future of the industry.
|3 Reasons to be the Early-Bird:|
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|FREE Registration. Need we say more? NPE2015 access is free, but only for a limited time.|
|No matter what kind of business you’re in, or what kind of products you make, you’ll find what you need here. Get your free pass today!|
Penn State Silicone Elastomers Course
Silicone Elastomers Technology & Fabrication Course
This course offers a comprehensive overview of silicone elastomers, including basic silicone chemistry, the important differences when building an LSR mold, material handling, education on how to choose the right equipment for your project/company, fabrication techniques, problem solving, manufacturing and application processes.
Presented by a panel of industry experts, this is a MUST for anyone new or inexperienced with liquid silicone rubber.
For more information, please call the office of Community and Workforce Programs at Penn State Behrend at 814-898-6103 or click here.