Exit

Tag Archive: Aerospace manufacturing

  1. Aerospace honing now offered by Primus Aerospace

    Leave a Comment

    What is honing?

    Honing is mechanical finishing process used by aerospace machine shops and outside processors to achieve a precision surface on a metal part.  Hones use superabrasives, also known as a honing stone, to a specific finish over the entirety of a metal surface.  These abrasive stones are configured on a tool assembly to provide consistent abrasion to the work piece..  Honing is also called bore finishing, as it’s most commonly conducted on cylindrical surfaces as a finishing technique.

    Honing is conducted with honing stones or with wire brushes that provide a very specific level of abrasion to the metal work piece.  Honing stones are generally an aluminum oxide or silicon carbide abrasive material, which is bonded with resin.

    Aerospace honing tool application

     

    Where did honing originate?

    Modern honing techniques date back to the 1940’s with the foundation of Superior Hone in Elkhart, IN.  The original intend of mechanical honing equipment was to deglaze automotive cylinder bores, but as the technique was perfected, additional applications presented themselves.

     

    What are common types of mechanical honing equipment?

    • Vertical hone – Vertical honing machines use a drive shaft that is oriented vertically and moves along the work piece in an up and down motion. An example of a vertical hone would be the Ohio Tool Works PowerHone.  Primus Aerospace utilizes an onsite Barnes 3010 honer to provide in-house honing as part of a turn-key manufacturing solution.
    • Horizontal hone – Horizontal honing machines are laid out across a floor footprint where the drive shaft moves forward and backward through a work piece. An example of a horizontal hone would be the Ohio Tool Works VersaHoneSunnen is another manufacturer that specializes in honing equipment for vehicle engine applications.

    Honing machines also differ in their capability to handle various bore diameters and part lengths / heights.  Primus’s honing capability specialize in parts that are ideally used for aerospace hydraulic reservoirs and cylinders.

     

    What is single pass vs multi pass honing?

    Most honing applications take multiple passes (known as stroke honing) to achieve the desired surface finish and depth.  Specific applications, such as engine crank arms or cam bores, require single pass honing to ideal performance.

    Barnes Drill Company Vertical Hone

    Why is honing performed in aerospace and defense applications?

    Honing allows a manufacturer to achieve a precision surface finish that is critical for some aerospace applications, such as hydraulic systems.  Aircraft manufacturers and tier one suppliers design hydraulic systems as part of the control system.  In addition to aerospace control systems, honed aerospace parts are found in pumps, valve sleeves, accumulators, fuse pins, and landing gear components.  Parts are honed to reduce friction, remove burrs, and increase equipment dependability over it’s service life.  In specific aerospace applications, the inner bores of gears or weapon barrels are honed.

     

    What is the advantage of a machine shop that has integrated honing?

    While many aerospace and defense machine shops offer honing as part of their production sequence, very few have the honing capability inside their company.  When aerospace machine shops produce a part, the production sequence may require additional capabilities (such as honing, painting, precision grinding) to meet the customer’s build-to-print requirements.  When those capabilities are not organic to the part manufacturer, they will utilize outside processors (also known as OP Houses) to perform the specialized work.  More sophisticated machine shops have additional value added services inside the company, which allows them to expedite priority parts and ensures adherence to a single quality management system (QMS), generally at the AS9100 level.  Primus Aerospace is constantly adding additional capabilities, such as wire EDM, honing, and grinding, to it’s ability to provide turn-key manufacturing solutions for aerospace and defense parts.

     

    Does Primus offer honing to aerospace & defense customers?

    Yes! Primus Aerospace offers honing as a valued added service to it’s build-to-print aerospace part production service.  Primus does not offer today, stand alone honing as a separate service to other local machine shops, but could in the future.

  2. 3D printing aerospace parts

    Leave a Comment

    This article provides an overview of the differences between additive and subtractive manufacturing, 3D printing technologies, 3D printing applications for aerospace and defense parts, and a look at how Primus utilizes titanium printing to support customers.   

    What is the difference between additive and subtractive manufacturing techniques? 

    Additive manufacturing, also known as 3D printing, is the process of creating an object, such as a critical satellite component, using material deposition and numerous post processing techniques. This is different than traditional subtractive manufacturing in one main way. Instead of taking a block of raw material and using lathes, mills, and CNC machines to remove material in a controlled manner, material is selectively added to a blank slate to build a component from the ground up. Subtractive manufacturing typically 

    3D Printing laser TI powder fusion

    uses cutting tools such as end mills, boring bars, or drill bits to remove matter from a block, bar, or slug of raw material. The tool (or the material if the machine in question is a lathe) is spun at a rapid rate and is ran through the material at computer programmed locations where stock needs to be removed. Through 3 and 5 axis machining, the work can be spun along various axes to remove material to form complex shapes. One alternative to subtractive manufacturing is 3D printing.  

    This seemingly new technology can be traced back to 1925. A patent was issued for the use of arc welding techniques to create sculptures and decorative articles by depositing welded beads of metal on top of one another to form baskets and other household items. 3D printing first found its use in manufacturing in 1982 when United Technologies Research Center filed a patent for a “Method for Fabricating Articles be Sequential Layer Deposition.” Initially, Additive Manufacturing was only used for rapid prototyping to develop a model for parts to be later created using subtractive methods. It wasn’t until the 2000’s that Additive Manufacturing began to achieved production-grade parts primarily for the medical implant industry. Since then, additive manufacturing has crossed over to the Aerospace and Defense supply chain for making high precision, low volume parts and components. 

    What are the key types of additive manufacturing / 3D printing? 

    • Stereolithography – This method utilizes liquid plastic to create 3D objects through layer-by-layer deposition. Liquid resign is collected in a vat with a clear bottom. UV light is used to trace a pattern in the vat and selectively cure the resin.  The object is dragged up by a platform to allow the part to grow from the base down [1]. This type of 3D printing is primarily used for rapid prototyping as it is too slow to produce plastic parts in a cost-effective manner.  
    • Fused Deposition Modeling – Fused Deposition Modeling feeds a thermoplastic filament into an extruder. This plastic is then deposited onto a plate to build a part layer-by-layer from the ground up. This is the most common type of 3D printing and is often seen in entry level printers. This method is also used for rapid prototyping and can be used along with Stereolithography to create negative molds for metal casting. 
    • Sheet Lamination– Sheet Lamination utilizes a cutting device (usually a laser) to slice through thin layers of material. These cuts are then deposited layer-by-layer and glued together to form parts. This strategy can be used with plastics, wood, and even metal to create prototypes and production level parts.  
    • Powder Bed Fusion– This strategy employs a laser or electron beam to weld or sinter layers of powdered metal together to from a part. Powder bed fusion is commonly employed by the Aerospace, Defense, and medical industries to create intricate, low volume production parts. The printer used by Primus Aerospace falls under this category. 

    What types of aerospace projects are best performed on a 3D printer? 

    • Prototype parts – Producing 3D printed parts requires very little setup, additional tooling or fixtures to create working parts for prototype or R&D applications. This allows design modifications to be verified with minimal effort. Engineers may 3D print a part for a prototype but later transition to precision machined parts as the program enters production phase.    
    • Complex designs – 3D printing allows designers to create parts that could not be produced with traditional subtractive manufacturing techniques.  While aerospace parts designers should not throw out the book on design for manufacturability (DFC), some applications do require designs that cannot be accomplished on a 5-axis CNC mill (such as integrated internal pathways and complex internal features).
    • Lightweight requirements – Additive manufacturing allows the incorporation of weight saving features and innovative designs that cannot be traditionally machined, such as complex lattice structures and intricate hollow structures. For example, aerospace engineers designing parts for a commercial satellite (where weight represents a high-payoff Value Engineering effort) can shed costly weight without sacrificing strength.  
    • Low production volumes  One drawback of 3D printing is its part production time. For a powder bed fusion system, builds take at least one day to print causing this technology to not be applicable for high production parts (yet).

    Additive Manufacturing at Primus Aerospace 

    Primus primarily uses a Velo3D Sapphire Metal AM Printer for additive manufacturing aerospace projectsThis machine is tailored to use powder bed fusion technologies to 3D Print space and satellite parts using a Ti 6Al-4V titanium alloy powder. 

    ThisThe Velo3D Titanium Printer  works by using a vacuum powered contactless recoater to deposit titanium powder over a build plate. The recoater dumps material over the plate, and then uses a vacuum to suck up any access metal an

     

    d ensure a consistent layer of powder. Two separate lasers sinter fuse the powder together in a predetermined pattern to methodically form a part from the base upFusion is the process of melting a two separate solid components and re-solidifying them together. This is done in layers that are slightly offset from one another to avoid empty space in the finished product. This ensures strength and reliability in precision aerospace parts. This is done on top of a build plate that sits on top of a piston, which lowers the plate to accommodate for each subsequent layer of titanium until the build is complete. The lasers and piston take instructions from Velo’s Flow software. This takes a CAD model of a part, slices it, and creates step by step instructions for the 3D printer to follow.  

    This machine has the capability to print material at low angles, parts with overhanging features, as well as internal passageways and cavities with little to no support structures. In turn, this decreases the need for post processing and allows primus to manufacture an extremely wide range of components. So far, we have used this machine to create one-piece parts with a high level of complexity, components with internal cooling passages, and thin-walled pressure vessels with an almost unattainable degree of precision.  

    Primus Aerospace supports aerospace, defense, and space manufacturers with build to print 3D printed titanium parts. Primus is able to combine this innovative 3D printing technology with other valued added services (such as finishing, grinding, or painting) and an aerospace AS9100 certified quality management system.

     

     

     

    By Josh Trujillo

    Sources 

    [1] 3D Printing | An Overview of 3D Printing Technologies (techpats.com) 

    [2] 3D Printed Lattice Structures and Generative Design • OpenFab PDX 

    [3] Velo3D launches its first metal Additive Manufacturing system (metal-am.com) 

    Images courtesy of Velo3D

Design Support
Design Support
Component Manufacturing
Component Manufacturing
Assembly & Integration
Assembly & Integration
programmanagement icon internalpage
Program Management

Our Customers Include: