Passivation, Dross and Weld Discoloration Removal

Many metals protect themselves from corrosion by forming a passivation layer on their outer surface.  This protective layer is composed of metal oxide or metal nitride and is very thin.  For stainless steels, the layer may be only 1-3 angstroms thick and for metals such as aluminum and titanium, the layer may be up to 50 angstroms thick. (A human hair is 500,000 angstroms thick for comparison).  Passivation can occur naturally with exposure to oxygen or can be assisted by various passivation techniques such as electrolytic anodization, plasma treatment or chemical treatment.  Due to the limited thickness of the passivation layer, the substrate being passivated must be very clean to begin with to prevent discontinuities in the passivation layer which would then compromise the protective nature of the passivation layer.

Machining, cutting, welding, polishing or otherwise “working” a metal substrate generally introduces contaminants which prevent the formation of a uniform passivation layer.  Even particulate in the shop air can contaminate the metal surface and prevent uniform passivation.  Magnus Engineered Equipment can supply the proper equipment to clean and passivate the metal substrates.

Laser or plasma cutting stainless steel or other metals can produce a dross which needs to be removed for part functionality and proper passivation.  The same is true for stainless steel or other metal discoloration that occurs from welding.  Often, aggressive etchants such as hydrofluoric acid and nitric acid are used to remove dross and less aggressive chemistry can be used to remove discoloration.  The use of ultrasonics is useful for removing dross and discoloration and the 20 kHz ultrasonics offered by Magnus Engineered Equipment is the most powerful ultrasonics in the cleaning industry.

Contact Magnus Engineered Equipment to see how we can assist with your metal passivation, dross and discoloration removal needs.

Ultrasonic Frequency in Cleaning Applications

In the simplest terms,


Properly applied, ultrasonics can perform a more thorough, more complete cleaning job than any other cleaning method. Ultrasonics is a non-destructive method of cleaning which utilizes sound waves to form and implode vapor pockets on the surface of contaminated parts. This implosion results in the release of stored energy that creates a virtual scrubbing or cleaning action on the surface of the part to be cleaned.

In ultrasonic cleaning, the pressure phase of a sound wave is used to provide the cleaning action. Sonication creates areas in the liquid where negative pressure exists. At these points on the part to be cleaned, thousands of minute vapor bubbles are formed and these bubbles effectively scrub the part. As the ultrasonic energy level alternates (a half second later) the pressure in this same zone becomes positive and the vapor bubbles implode. This implosion (the bubbles bust inwardly) occurs with great violence. This action is commonly called “cavitation” and is not to be confused with the formation of air bubbles caused by degassing of water. While the quantity of energy in any one implosion is extremely small, it is calculated that enormous pressures in the order of 10,000 pounds per square inch and extreme temperatures of approximately 20,000 oF are generated. This cavitational activity–the formation and bursting of these vapor pockets–actually forms the scrubbing or cleaning action on the surface of the part.

Power Sonics TM Ultrasonic Transducers – A Magnus Engineered Equipment Exclusive

Power SonicsTM ultrasonic transducers are mechanically strong and capable of handling large amounts of power – a desirable feature when difficult cleaning jobs are encountered. Power SonicsTM operate at a frequency of 20 kHz whereas conventional sonic cleaning systems operate at 25 or 40 kHz. To see the difference in cleaning power, we need to examine the following chart.

Ultrasonic Cleaning Power



Note that the “y-axis” is the relative strength or cleaning power of the ultrasonic system.

Ultrasonics running at 20 kHz are 5 times stronger than those running at 25 kHz and about 20 times stronger than those running at 40 kHz.

Greater cleaning power allows for faster cleaning speeds, more efficient cleaning, and the ability to clean the toughest substrates.


Sand, Core and Shell Investment Casting Removal

Sand, Core and Shell Investment Casting Removal Using Caustic Leaching

Magnus Engineered Equipment (MEE) has supplied equipment to the investment casting industry for more than 50 years. Investment casting, or die casting, is a technique for forming metallic components having complex geometries, especially hollow components. Hollow cored super alloy airfoils and gas turbine engine components are examples of complex geometries produced with the investment casting process. MEE equipment is used with concentrated caustic solutions of NaOH (sodium hydroxide) or KOH (potassium hydroxide) to remove shell residues from ferrous and non-ferrous metal castings (including aluminum). Operating at just below the boiling point of the solution, the process breaks down the fused silica shell used in the investment casting process without damaging the metallic substrate. The process is faster, safer and more efficient than mechanical methods of shell removal and all surfaces within the substrate are cleaned.

MEE supplies equipment which uses heat, agitation and turbulation to quickly and effectively remove the shell residues from substrates including the complex geometries found in many castings. The effect of agitation and turbulation increases the dissolution rate by increasing chemical mass transfer at the shell interface. Agitation and turbulation act to quickly remove dissolved silica and spent chemistry from the substrate surface while bringing in fresh chemistry to continue the dissolution reaction at the fastest rate. MEE supplied equipment also continuously filters the bath thus removing dissolved silica and enhancing the dissolution rate of the remaining ceramic shell by returning clean chemistry to the part surface.


The temperature at which the caustic solution is operated is dictated by the concentration of the NaOH or KOH used. As a rule of thumb, it is advisable to operate at a temperature which is 20 oF below the boiling point of the solution being used so as to prevent cavitation in the pumps used to circulate the solution. (The lower pressure on the suction side of the pump lowers the boiling point of the solution). Most users of MEE equipment operate with a NaOH or KOH solution concentration of 35 to 50 wt%.


MEE supplies off-the-shelf or custom designed equipment for investment casting removal applications. Material handling, by-product removal, automation and post-processing needs can be addressed by MEE to make the overall process efficient and worry-free. Contact MEE today to discuss your investment casting application.

Ultrasonic Cleaning Power

Magnus Engineered Equipment manufacturers it’s own Ultrasonic transducers and generators.  Power Sonics ™ line of transducers offer unmatched cleaning consistency whether the parts to be cleaned are large or small, simple or complex, handled singly, in batches, or in an automated line.   Because ultrasonic energy penetrates into crevices and cavities, any type of part or assembly can be cleaned such as precision parts or assemblies.  Having the capability to clean entire assemblies without disassembly results in labor savings that makes ultrasonics the most economical way of cleaning.  The Power Sonics ™ line includes both radial and flat 20 kHz transducers which optimize energy transfer to the bath to maximize ultrasonic scrubbing.

The exclusive Power Sonics TM lamination design results in a transducer which achieves cavitation easily and quickly. This occurs in relatively un-degassed as well as fully degassed solutions. As the name implies, power in the bath directly affects cleaning capability. The 20 kHz magnetostrictive transducer, driven as a uniform unit by an intense generator signal, optimizes energy transfer to the bath to maximize ultrasonic scrubbing. The design produces the highest cavitation intensity and highest power density available in the market.  Power levels of 10 Watts per square inch are achieved!

Radial transducers are cylindrical and expose parts to “full surround” ultrasonic sound waves, thus providing cavitation much greater than “flat” transducers.  For products such as wire, cable, tubing, channel, flat stock, rod, pipe and other materials which can be passed through the radial ultrasonic unit, the ability to clean with a radial ultrasonic unit is unmatched in the sonics industry.  Product can be cleaned through the Power Sonics TM radial transducers at any speed desired and in the smallest footprint owing to the design of the radial transducers.  Unlike systems which utilize flat transducers, the use of radial transducers eliminates “sonic shadowing” and ensures that the entire surface of the product is cleaned !  This feature is important for cleaning of continuous product where 100% surface cleanliness is desired.

Magnus Engineered Equipment has a breadth of experience in designing and manufacturing ultrasonic cleaning equipment to clean any type of substrate from bearings to surgical needles.  Transducers made from special alloys are available as are hardened surfaces.  Magnus Engineered Equipment can recommend the proper cleaning chemistry to optimize the performance of the Power Sonics TM equipment.  Contact Magnus Engineered Equipment to see how Power Sonics TM can be used in your cleaning application.

20 kHz Magnetostrictive Ultrasonics….the most powerful ultrasonics for cleaning applications.

The table below shows the difference in ultrasonic cleaning power as a function of ultrasonic frequency.  Magnus Engineered Equipment (MEE) offers ultrasonic cleaning equipment in a variety of frequencies, but MEE’s 20 kHz magnetostrictive offering is the most powerful ultrasonic cleaning technology in the industry….period !   In order to achieve this level of cleaning power, MEE builds it’s own transducers and generators.  Magnetostrictive transducers are used to deliver the 20 kHz high power not deliverable with piezoelectric transducers.  Some vendors may claim that their 25 kHz or 28 kHz systems deliver the same power as a 20 kHz system, however as one can see in the figure below, the power delivered by 20 kHz is much higher.

Ultrasonic Cleaning Power



Green Alternative to Hazardous MEK Solvent

A new customer approached Magnus Engineered Equipment looking for help cleaning parts from adhesive and hot glue dispensing label machines.  In their current process, parts are soaked overnight in MEK and then manually brushed clean.

MEK is a highly toxic and unfriendly solvent to humans and the environment, in addition to the costly removal of the hazardous waste by-product.

Two separate removal applications were submitted to Dave Stankiewicz at MEE for cleaning.


Adhesive (Henkle) Removal –

Adhesive Removal2 Adhesive Removal

Hot Glue (DURA PRO – M-749) Removal –

Hot Glue Removal Hot Glue removal2

Once MEE received the customers parts, Dave partnered with our in-house chemical engineer to determine a less toxic solution.  Upon their investigation they developed and refined an eco-friendly, bio-degradable cleaning solvent for both cleaning applications.


Test Results –

We were successful in removing the adhesive (Henkle Aquence PS 2417/GELVA GME2417) and Hot Glue (DURA PRO-M-749) from the adhesive & hot glue dispensing label machines. We used a 50/50 blend of the eco-friendly cleaning solution in a heated, wash/agitation tank and a heated, clean water, rinse/agitation tank.


Final Product –



Willoughby, Ohio – Magnus Engineered Equipment LLC (MEE), a leading manufacturer of industrial cleaning equipment, announced the successful implementation and launch of the Epicor Cloud ERP solution on April 25th.  The goal was to replace an outdated legacy system with a fully integrated state-of-the-art, modern enterprise resource planning system. The new system allows MEE to improve its production planning capability and provide better customer service.

All of the company’s historical data was preserved and accessible by our customer service team through a secured database.  This data includes customer order detail, supplier purchasing history, and detailed parts master descriptions. The company continues to maintain a serial number database for equipment manufactured dating back to the 1930’s.

The new ERP application will enhance the customer experience by:

  • Providing customers accurate capable to promise delivery dates
  • Allow the capability to seamlessly integrate with the company’s new online store
  • Future mobile and customer-facing applications to improve customer interface

Jeffrey MendralaChief Financial Officer, MEE, said “This success was only possible by having the right team in place to deliver and set up MEE for success. The new Epicor solution will provide the platform to allow MEE to execute on its strategic plan for the long term.

Acetone Replacement

A company which manufactures composite pressure vessels was manually cleaning resin contaminated stainless steel components with Acetone and manual scraping.  The company wanted to find a better way of doing this and approached Magnus Engineered Equipment.  In order to be successful, fully cured and partially cured resin materials needed to be removed from a variety of stainless steel substrates.  Magnus Engineered Equipment provided a process which uses novel bio-degradeable chemistry to economically remove cured and uncured resin in very fast times (less than 30 minutes).  The novel chemistry lasts longer and costs less overall than the acetone it replaces, and no manual labor is required.  Furthermore, operator exposure to acetone and acetone disposal issues were eliminated.  This “green” process can also be used to replace other common cleaning agents such as Methyl Ethyl Ketone (MEK), toluene and other thinners as well as remove other organics such as polyester, vinyl ester or epoxy resin, gel coats, adhesives, urethanes, waxes, paints and stains.

Capital Investment Decisions – Process

Effective capital investment decisions must allocate constrained resources (cash) to projects that will return a positive cash flow over a time horizon dictated by an owner or by corporate policy.  You might hear the term hurdle rate used by your financial department or banker.  The hurdle rate is the minimum rate that your company expects to earn when investing in a project. The hurdle rate is also referred to as the company’s required rate of return (ROI) or target rate. Typically a project’s internal rate of return must equal or exceed the hurdle rate.  When there are multiple demands for cash for example, a new marketing campaign, geographic expansion plans, a need for additional production capacity, replacement of outdated or high maintenance equipment, each project will be prioritized depending on the cash they generate over a predetermined time frame.  The time frame will play an important role if the company is currently focused on projects that provide prompt returns versus projects which will contribute to future growth.  The factors below will influence capital investment decisions:

  • Management’s outlook (positive or negative)
  • Opportunities due to technological improvements
  • What the competitor is doing
  • Changing customer requirements
  • Cash flow budget
  • Economic forecast
  • Other non-financial factors

You want to avoid reaching a capital investment decision subjectively then apply financial metrics in an attempt to rationalize the decision.  As I referred to in a previous discussion, internal politics can play a role in subjective decisions when individuals or groups have a personal interest in certain projects.  The capital investment process usually involves the following seven steps:

  • Project identification
  • Project definition
  • Analyze the project benefits (financial and non-financial)
  • Approve capital investment
  • Implement the project
  • Project management
  • Audit and report actual benefits versus assumptions

I will dig deeper into each of these steps in my future discussions.  As I discuss each step I will post user friendly templates on our website that can help improve your capital investment decision process.

Capital Investment Decisions

My first job out of school was analyzing and shepherding ‘Authorization For Expenditure’ packages (Capital Equipment Requests) from executive to executive at Daimler.  Each executive depending on which part of the company they were responsible for, looked at these requests differently.  Each required financial justifications that they were comfortable with and each had their own pet peeves.  Organization politics also played a prominent role when individuals or groups had a personal interest in certain projects.  This would sometimes increase the number of obstacles, the amount of information required, and how long it might sit on some ones desk.  This was long before task management software was fashionable so most of my interactions were face to face.

What I learned from these personal interactions was the need to leave nothing to chance when it came to the information I prepared to support of the funding request.  An incomplete submission, or not including information a particular executive was looking for, meant a long walk back to the financial department bullpen for a redo.

I took these lessons with me throughout my career to where I am today, as an owner of a capital equipment manufacturer.  The goal of these posts are to help you develop your own capital spending request whether you own a twenty person machine shop or you are where I was early in my career at a Fortune 500 company.   Future topics will include: capital evaluation techniques, investment plan development, financial modeling, economic analysis guidelines, new versus used equipment, finance methods, and tax strategies.  As I move through these topics I will post user friendly templates on our website and welcome questions that might develop.

Magnus Engineered Equipment

We are pleased and excited to announce that Magnus Engineered Equipment LLC has agreed to acquire the Magnus Equipment Company.

Our plans are big; we will take what has been accomplished over the past 95 years and grow a company that embraces continuous improvement. Our products are found in various industries that produce mechanical components such as aerospace, automotive, remanufacturing, energy, castings, medical technology, and electronics.

Some of our plans have already been set in motion. We are in the process of designing a new facility that located in Northeastern Ohio. This facility is being designed with innovation and efficient production processes in mind. We will continue to design, test, and manufacture all of our products under one roof. ISO certification is planned for the fourth quarter of 2016. We have begun to contact our key suppliers to form strategic partnerships that will improve our product capability while also reducing cost. To improve our capability to promise accurate delivery dates, we are in the process of implementing the latest version of EPICOR’s ERP solution.

This is just a start. We are adding additional engineering and design expertise giving us the most talented technical team in our industry. We are also expanding our ability to analyze and develop the cleaning chemistry needed to meet our customers’ cleanliness requirements. Once we have relocated we will be investing in new manufacturing equipment that will improve our capability and quality.

With innovative standard solutions and individually customized cleaning systems, Magnus Engineered Equipment will meet all of our customers’ requirements.

We can’t wait to start working with the team at Magnus to build a company that embraces the newest technology to continuously improve our products and services for all of our customers.

William Martin – President/CEO
Jeffrey S. Mendrala, CPA, CVA – Chief Financial Officer