The urethane casting build process involves first creating a master pattern — essentially a replica (often 3D printed) of the final part. The pattern is then fully encased in liquid silicone and allowed to cure. The mold is cut into halves and the pattern removed. From there, the process can be repeated using the proper urethane casting resin.

Polyurethane casting materials are capable of providing performance characteristics comparable — if not superior — to the thermoplastics used in injection molding. However, as with other production methods, the process of casting high-quality parts that meet all performance requirements also requires that product teams follow design for manufacturability (DFM) best practices. Here are some of the most important guidelines for product teams to keep in mind:

Tolerances

Some degree of variation is inevitable in manufacturing (though teams should endeavor to account for as many of the variables as possible), and tolerances are the acceptable amount of dimensional variation between individual units. Cast urethane tolerances are typically around  ± 0.015” or ± 0.003 per inch, whichever is greater. Tighter tolerances may be offered on a case-by-case basis.

In general, a shrinkage rate of +0.15% is typical. This is caused by the thermal expansion of the urethane casting material and how the flexible silicone mold warms in response.

Additionally, it’s important to note that while urethane cast parts take well to post-processing (though additional processes, such as polishing or custom finishing, can quickly drive up production costs), some design features like sharp corners or lettering may experience slight rounding in the cooling process, impacting the definition of finer details. That said, it is possible to add a finish to the master pattern that mimics an SPI finish or texture. You can also paint urethane cast parts to match Pantone colors, and certain color and pigments can be added directly to the casting materials, as well.

Wall Thickness

Parts produced with urethane casting should have a minimum wall thickness of 0.040” (1mm), though walls as thin as 0.020” (0.5mm) can be achieved for some small components. Larger parts generally require thicker walls in order to ensure the piece’s structural integrity.

Urethane casting does allow for parts with varying wall thicknesses or irregular geometries, but designing parts as such should be done only when strictly necessary. Maintaining a consistent thickness helps to minimize the potential for improper shrinkage and deformation during the curing process.

Undercuts and Draft

While undercuts can quickly complicate injection molding design, the flexible nature of the silicone molds used in urethane casting typically allows for parts to be removed easily and without damage.

The same is true for draft angles: they are a necessity for ejecting pieces from metal molds, but less essential for urethane-cast parts. That said, incorporating 3-5 degrees of draft into part design can significantly reduce strain on your mold and extend its life cycle.

Ribs

Ribs add stability and strength, but it’s important to ensure that they are oriented so as to maximize the bending stiffness of the walls they support. As a general rule of thumb, the rib’s height should be no more than three times its width, and the width of the rib where it meets the part wall should be between 40-60% of the wall thickness. Lastly, to maximize the strength of the rib, all interior corners should have a fillet radius of at least 25% of the part’s wall thickness.

Bosses

Bosses allow secure mating parts to be attached through the use of screws, pins, and other fasteners. As with ribs, the base radius should be about 25% of the part’s wall thickness, which has the added benefit in this case of helping to prevent the fastener from burning when it’s set into the boss.

Interior boss corners should use a 0.060” (1.5mm) fillet radius to minimize thickness and reduce the likelihood of sinks developing. Ensuring that bosses are no more than 60% of the nominal wall thickness also helps to minimize shrinkage.

Leverage the Benefits of Urethane Casting Today

The advantages of urethane casting — short lead times, low cost, and design and material flexibility, to name a few — only truly pay off if you adhere to design and manufacturing best practices. This means paying attention to variables like urethane casting material properties, general tolerances for rubber parts, and everything in between — which quickly becomes complicated without the assistance of an experienced manufacturing partner.

With our agile approach, we’re able to significantly shorten lead times and increase operational efficiency for product teams of all shapes and sizes. And at SyBridge, our business isn’t just based on manufacturing superior parts — we also work tirelessly to make sure that our production processes are as efficient as possible, even if that means using a combination of techniques to get the job done. Contact us today to learn more.

The post Critical Design Guidelines for Urethane Casting appeared first on SyBridge Technologies.

Multi Jet Fusion enables the efficient production of end-use nylon parts using additive technologies. Here’s a checklist for design teams.

Introduction

What is Multi Jet Fusion?

Multi Jet Fusion (MJF) is an industrial form of 3D printing that can be used to produce functional nylon prototypes to higher volume production parts with exceptional design freedom and mechanical properties. The MJF process works by using inkjet nozzles to selectively distribute fusing and detailing agents across a bed layered with nylon powder. Unlike selective laser sintering, which uses lasers to fuse the powder into solid material, the MJF printer uses a continuous sweeping motion to distribute agents and apply heat across the print bed layer by layer until the part is finished, MJF can produce high-quality parts at high speeds.

This manufacturing process also does not require support structures to produce parts, making it possible to create complex geometries like internal channels or co-printed assemblies. MJF parts have mechanical properties comparable to injection-molded ones, but without the need for expensive tooling.

Designing for manufacturability will go a long way in ensuring optimal part quality and yield, minimizing post-processing needs, and driving cost reductions. Here’s a quick checklist to help your team ensure that you’re following MJF design best practices.

1. Is MJF a suitable process for my project?

Before diving into design changes, it is important to ensure that the MJF process will meet all product requirements. Here are a few questions to ask yourself:

Do any of the material offerings meet my product requirements?

While MJF has many strengths, it has a limited list of approved materials. PA12 and its glass bead counterpart are fairly versatile for rigid plastic applications. TPU, a flexible polyamide, can find use where an elastomeric material is required. If the available materials do not meet a specific requirement, you may need to consider a different process.

Does my part fit in the build volume?

One key limiting factor is the machine’s build volume, which is 380 x 380 x 284mm for the Jet Fusion 4200. In some cases, large parts can be printed as smaller subcomponents and assembled using adhesive or mechanical joints. In this case, design features such as dovetail joints may facilitate alignment and adhesion.

Do I have any tight tolerances I need to hit?

While the gap between additive and injection molding tolerances is narrowing, it is important to make sure that MJF’s tolerances are sufficient within the context of your assembly.

2. Are there areas where I can use less material?

In most cases, MJF defects are caused by thermal gradients that develop during the build. If the material cools unevenly, the piece may warp or develop sinks. Parts that are long and thin, have abrupt changes in cross-sections, or have thin curved surfaces are especially prone to shrink-induced warp.

Removing material from part designs wherever possible through the use of pockets, shelling, lattices, and topology optimization is key to mitigating and preventing these defects. Avoiding large changes in cross-sections is another way to limit warp. Ensure that chamfers and fillets are incorporated where needed throughout the part design to make the transitions between different features more gradual.

3. Are my features above the minimum threshold size?

In general, the wall thickness of MJF-printed parts should be a minimum of 1.5mm. Small design features should also be no smaller than 1.5mm, though some features such as slits, embossing, engraving, or the diameters of holes and shafts can be as small as 0.5mm. For embossed or debossed text, the font should be no smaller than 6pt (approximately 2mm) and should be a minimum of 0.3mm deep.

If a part includes screw threads, they should be M6 or larger. Where smaller, more precise, or more durable threads are needed, consider using threaded inserts. Beyond feature resolution, you should also consider how small, slender features might break off in post-processing.

4. Have I taken assembly tolerances into account?

Even with the greater geometric flexibility provided by the MJF process, some applications may still require a part to be assembled from multiple components. In general, mating faces should have 0.4 – 0.6mm of clearance to ensure that the components can properly fit.

If your project involves co-printing assemblies, the components printed together should have at least 0.5mm of clearance, but may require more, particularly when there are thick cross sections or there is a significant contact surface area.

5. Is my part design optimized for post-processing?

If your part requires post-processing, there are a few things to double-check in your design to help make secondary operations more effective.

1. Ensure that there are no unvented or trapped volumes in the design.
2. Avoid blind holes whenever possible — these are hard to clean, which can quickly drive up costs.
3. Add fillets to corners where the powder can cake and become difficult to remove through standard tumbling and bead blasting.

6. Have I seized every opportunity to lower part costs?

Besides improving part quality, intelligent DFM changes can drive cost savings. Lightweighting your part, for example, reduces the risk of defects and lowers the material cost per part. The other main consideration when designing for MJF and cost is optimizing nestability in a build. Adding draft or altering the position of printed assemblies may increase the number of parts that can fit per build and distribute fixed costs over more parts, lowering the overall part cost.

In addition to optimizing designs for manufacturability, additional factors to consider include your part’s cosmetics, surface finish, and ease of storage and transportation. MJF parts are naturally grey, but can be dyed black easily. If painting, priming, or other processes are not essential to the part’s function, they can be foregone to reduce expenses. Most MJF-printed parts will have a 125-250 microinches RA finish — if a smoother surface is needed, the part can undergo a variety of surface treatments, including sanding, tumbling, or vapor smoothing. Texturing can be an effective design technique to improve part aesthetics without additional post-processing.

Getting Started With a DFM Expert

Adhering to DFM principles is key to the success of manufacturing processes for a number of reasons. It helps to keep your operating expenses as low as possible, allows you to detect and address design issues early, and improves your overall part quality. This checklist is a valuable resource for making sure your MJF parts are optimized and refined before production begins.

The added advantage of partnering with SyBridge is that your team gains access to the latest in digital design technologies and expert advice. Our team is standing by to help guide each project from design and prototyping through to fulfillment, ensuring that you receive superior-quality parts on time and at the right price. Contact us today to get started.

The post HP Multi Jet Fusion Design Guidelines appeared first on SyBridge Technologies.

DFAM draws on the same idea as design for manufacturability (DFM) — integrating process planning and product development. But instead of optimizing a product for urethane casting or injection molding, DFAM optimizes a product for production-grade manufacturing with additive technologies by analyzing competing factors to develop the most efficient design.

Additive manufacturing isn’t as simple as hitting print, especially when using DFAM principles to design a part for industrial-grade quality while minimizing production costs. But the resulting parts meet the performance of traditionally manufactured parts while reducing lead times, eliminating tooling costs and maximizing design flexibility. Leveraging DFAM guidelines early on in the product development process allows product design teams to optimize their designs to capture the value of additive manufacturing.

Here are a few common principles of DFAM to consider when leaping from additive manufacturing for prototyping to additive manufacturing for production:

Minimize Overhangs and Reduce Reliance on Supports

Each successive slice of your part as it is printing (e.g., in FDM, DMLS, etc.) relies on the layers below it for support. Large overhangs, openings and other features may require additional support during the build to prevent warping and ensure the product achieves its performance tolerances.Parts designed with DFAM principles in mind will be self-supporting, minimizing the need for supporting features which can add cost through material waste and added post-processing needs. And if supports are required, one cost-saving consideration would be to orient the part so that supports are placed in regions that aren’t user-facing, where marks are acceptable. This reduces the sanding and finishing time required in post-processing.

Part Orientation

While additive manufactured parts can be built in many orientations, the angle at which a feature is built can affect its tolerances. And because features can only deviate from the spec so much until it affects tolerance limits, it’s important to consider a range of possible orientations early on in the design process. That way, you can identify which orientation is best-suited for producing your part.

Consolidate Multi-Part Assemblies

It’s difficult to produce complex shapes with traditional manufacturing, which can necessitate creating some products as multi-part assemblies. If you are transitioning your product from traditional to additive manufacturing, it can often be consolidated into fewer parts to significantly reduce assembly costs. When Steelcase designed an arm cap using for additive manufacturing, for example, we transformed a three-part assembly into one uninterrupted part with multiple functional zones

Leveraging Generative Design to Optimize Your Part

The unique geometries possible through additive processes allows product designers to leverage generative design tools (e.g., topology optimization or lattice structures) to optimize the structure of your part based on hundreds of variables. And because lattices allow you to precisely tune the strength and material density in different regions of a part, one contiguous part can meet different performance requirements in different regions.

The Most Important Additive Manufacturing Design Consideration

None of these guidelines address one of the biggest obstacles to transitioning to production-grade additive manufacturing: An additive manufacturing product design skills gap. Because of this gap, the most important design guideline is to align yourself with additive manufacturing product design experts at the outset of any DFAM project. They will recommend design modifications that will optimize the cost and performance of your product. And they’ll understand how to drive efficiencies at the supply chain level through on-demand production and virtual warehousing. The sooner you involve expert AM design and engineering support, the greater the benefits you stand to earn with your switch to additive.

Interested in learning more? Be sure to check out our article on how to go beyond prototyping, and make your case for additive. At SyBridge, we’ll partner with companies across industries to discover, design and develop any part or product using additive manufacturing technologies. Learn how our experienced additive manufacturing design team can partner with you to design and deliver production-grade parts precisely tuned to your performance and design requirements. We’ve helped multi-million-dollar companies capture value with additive manufacturing, and can help you with your application, too. Get in touch with us today.

The post Applying Smart Design Principles to Amplify Benefits of Additive Manufacturing appeared first on SyBridge Technologies.

To ensure you maximize the potential of your 3D printed part for speed, quality, and cost, it’s important to understand support structures and how they should be integrated into your additive manufacturing project.

What are Support Structures in 3D Printing?

Support structures hold up elements of a 3D printed part which have no supporting material during manufacture. Not all 3D printing processes require support structures: while the Stratasys Fused Deposition Modeling (FDM), Carbon Digital Light Synthesis (DLS), and Stereolithography (SLA) processes often require supports, HP Multi Jet Fusion, which is a powder bed printing process, does not.

In the Stratasys Fused Deposition Modeling (FDM) additive manufacturing process, for example, layers of heated extruded material are built up from a print bed by adhesion to the material layers below them and may overhang those lower layers in order to create an angled surface. When that angle exceeds 45° the overhanging element generally requires support or the weight of the unsupported material will cause the element to collapse and the print to fail.

Where supports are required, they must be integrated into the part design and printed into the part when it is produced. Of course, this means accounting for the extra time and material that will be required during the 3D printing process and the subsequent post-process removal of the support structures.

Exceptions: Not all additive manufacturing methods require support structures. While 3D printing technologies such as fused deposition modeling (FDM) print parts by adding layers of material to a print bed, others, such as HP Multi Jet Fusion (MJF) print parts from a powder bed. Since the layers of powder are self-supporting, HP MJF part designs do not need to incorporate support structures.

What Types of Support Structures are Available?

Support structures for 3D printed parts vary in design and type but can be broadly organized into two categories: ‘trees’ and ‘fences’.

• Tree supports: Resembling branches or trunks, tree supports may enclose a part and fit neatly to angled surfaces for ease of removal. Tree supports can be designed, applied and tested quickly as part of a 3D printing project, enabling rapid iteration. Their branch-like structure means they can reach out over distances to support specific areas.
• Fence supports: Resembling walls, and with a variety of mounting points, fence supports are printed perpendicular to a part’s surface often with a lattice structure. Fence supports are more durable and easier to remove than tree supports, and are typically a better choice for cosmetic pieces or high volume production.

When Should I Use Additive Manufacturing Support Structures?

The ‘45° rule’ suggests that 3D printed overhangs of 45° and greater will require support, while those under 45° will not.

However The 45° rule should be considered a general rule of thumb and the need for support structures will vary depending on the complexity of part design and on the material being used. In some cases, bridging may offer an alternative to support structures: bridging is a technique in which heated additive material is stretched across a short distance (usually less than 5mm) without compromising the integrity of the part.

The ‘YHT’ principle: When conceived as 3D printed models, standing upright, the letters Y, H, and T are useful for illustrating the necessity for additive manufacturing support structures.

• The letter Y: Two arms extend from the letter Y at 45° – the angle of their overhang does not necessitate support structures. The further the overhang angle exceeds 45°, the more likely it is that support structures will be needed.
• The letter H: If the two vertical elements of the letter H are within 5 mm of each other, it may be possible to 3D print the horizontal element of the H with a bridge. If the vertical elements are further than 5mm apart, the horizontal element may require support structures.
• The letter T: The two arms of the letter T extend from the vertical element at 90° and will require support structures.

Beyond the angle of an overhang, other factors may affect the need for support structures. These include the quality of the 3D printer and the speed at which it prints: slower printers, for example, may increase the need for support structures.

Support Structures: Manufacturing Challenges

Support structures are a necessity in many additive builds but it’s important to remember that they can significantly affect the cost of a part in volume production — not to mention the amount of waste material that the project ultimately produces. Care should also be taken when removing support structures since they may damage or mark the finished part as they are detached.

With those factors in mind, 3D printed parts should ideally be designed to minimize or eliminate the need for support structures and, where possible, design for additive manufacturing (DFAM) principles should be applied in order to optimize parts for quality, cost, and production time. The following strategies may help to reduce the need for support structures:

Orientation: The orientation of parts on the print bed may affect the need for support structures. Overhangs, for example, may be eliminated by rotating a part onto its back or side. In the examples above, laying each of the 3D model letters Y, H, and T on their backs would completely eliminate any overhanging elements along with the need for support structures or bridges.

Part geometry: Where possible, remove overhangs from your design – or reduce their angle to less than 45°. Obviously, functional requirements may make the total elimination of overhangs impossible but you may be able to introduce alternative design elements such as chamfers, gussets, and radii to make the part’s geometry more self supporting.

Part separation: 3D printing technology enables the production of complex single parts, but if the amount of support those parts needs reduces their quality or cost-effectiveness it may be worth splitting the part into smaller components which can be assembled later. Spherical parts, for example, require substantial support but by splitting them in half, and creating a large flat surface, it’s possible to eliminate the need for supports completely.

Support density: The pressures exerted on support structures will dictate how strong they need to be and how much material is required to print them. To ensure a successful and cost-effective print, ensure your support structures are dense enough to support the size of the overhanging element. Bear in mind that the denser the support structure, the more difficult it may be to remove post-print.

Dissolvable supports: Some 3D printing technology may be able to print support structures in a separate dissolvable material, via a secondary print nozzle. These support structures can be submerged in water or chemicals, post-print, and dissolved to leave an intact part. Dissolvable supports reduce the potential for damage to the finished part during the support structure removal process. Most FDM additive materials have dissolvable supports, DLS and SLA materials do not. The HP MJF process does not require supports at all.

Getting Started

Support structures will continue to play an integral role in most additive manufacturing projects.

While the goal is always to reduce or eliminate the need for support structures, our engineers aim to optimize your part for functionality and cost. If you’d like to know more about how we can make your additive manufacturing project possible, contact the SyBridge team today.

The post Additive Support Structures: Why They Matter and How to Design for Them appeared first on SyBridge Technologies.

During the Fused Deposition Modeling (FDM) 3D-printing process, the 3D printer reads the digital file, divides the object into slices, and extrudes molten plastic material through a nozzle layer by layer to form the final part. The process seems straightforward, but there are many factors that can affect the quality of your final print, from your chosen material to the features on your design. The height of each individual layer in your part can also have a huge impact on the final product. Let’s explore this in greater detail.

3D Printer Layer Height 101

Layer height is a measurement of how much material the printer’s nozzle extrudes for each layer of your part. It’s measured in microns or millimeters, can be adjusted through a slicer program, and varies from project to project.

Just as the number of pixels determines a television’s resolution, a print’s layer height determines its resolution. Lower layer heights require more layers to achieve the same height, which increases the part’s quality and smoothness. Unfortunately, it also increases its print time, which correlates with an increase in cost. Taller 3D-printing layers take less time to print, which makes your part less expensive to print, but the trade-off is that parts will have a lower resolution.

If your design is artistic, highly detailed, or must be incredibly precise, choose a lower layer height. Likewise, opt for a lower layer height if your part has holes, angles, or curved surfaces — otherwise, it may develop noticeable steps due to the layered nature of 3D printing. 3D printing with smaller layer heights can also help if your design has overhangs, as layers will overlap more. However, be wary of using thin layers below 0.1mm, as these increase printing time and the possibility of imperfections while offering diminishing returns concerning your part’s visible quality.

On the other hand, if you need to print a part quickly, keep costs low, or are prioritizing function over aesthetics, you’ll want to use a larger nozzle and a taller layer height. A taller layer height means your printer has fewer layers to print to achieve the same volume, which speeds up the printing process and gives you a fully functional product at a lower cost. However, your part will also have fewer details and lower quality. The good news is that you can always sand, paint, or dip your product in an acetone bath to improve its appearance.

In addition to considering your desired balance of function and aesthetics, you will need to take into account the type of FDM 3D printer your part is being produced on when deciding which layer height to use. If your layer height is too low for the printer nozzle’s diameter, it will struggle to push out the filament, but if it’s too high the layers won’t stick together. A good rule of thumb is to keep your layer height between 25% and 75% of the printer nozzle’s diameter.

Key Considerations for 3D Printer Layer Height

When deciding your layer height, you’ll want to think about the specific 3D printing process you’re using because some printers have smaller minimum layer heights. When printing a part via FDM, layer heights typically range from 0.05mm to 0.4mm, with 0.2mm being the most common.

How do you decide whether to print on the higher or lower end of an acceptable range? The answer depends on your part’s design and purpose. You’ll want to ask yourself:

• How detailed is my component and how precise does it need to be?
• Does my part have holes, curves, or angled surfaces?
• How fast does my print time need to be?
• How strong does my component need to be?
• Does it matter if the surface is smooth?
• Will I be post-processing this component?
• Is my part’s aesthetics or functionality more important?
• What is my target cost-per-part?

Once you’ve answered these questions, you can find a layer height that offers the balance of resolution and speed that your part requires.

Reach New Heights With SyBridge

Your layer height can affect print time, quality, cost, strength, and more, so choosing an appropriate layer height is essential. If you’re unsure which layer height is best for your project, consider working with a trusted manufacturing partner.

When you work with SyBridge, you’ll gain access to an experienced team that can help you select the right layer height for your project to ensure a fast and high-quality print. Contact us today to get started on your next project.

The post Why Does 3D Printing Layer Height Matter? appeared first on SyBridge Technologies.

Exploring AM as a means of production opens up design and performance possibilities simply not possible with CNC machining, urethane casting or injection molding. This article will cover how organizations can:

• Identify if there’s a strong business case for switching to AM for your part or product.
• Leverage design for additive manufacturing (DFAM) principles for a seamless transition from rapid prototyping to rapid production.

Building a Business Case for Adopting Production-Grade Additive Manufacturing

Generally speaking, switching to production-grade AM for a part or product makes sense if there’s potential for adding value through:

• Lightweighting Your Product 
  Lightweighting products using AM advances material usage and performance — and opens up opportunity to capture savings throughout the product’s lifecycle. AM has enabled the weight reduction of aerospace parts by as much as 70 percent, saving about $3,000 per year in fuel.
• Low-Cost Mass Customization
  Consumer demand for customization is rising, with 30 percent of Americans interested in product personalization. And additive manufacturing uniquely allows product designers to meet this demand with lower customization costs and lead times than legacy production methods.Once the base component of your product has been validated with AM, personalizing the product with a corporate logo or different texture is a simple change in the CAD file — with no custom tooling required. Allowing consumers to tailor a product to their design preferences or needs not only helps you stand out among the competition, but it also ultimately provides more value to the customer.
• Enhancing Your Product’s Performance
  Virtually any shape, feature or function can be produced using AM. And product designers can experiment with vastly different geometries and textures with each design iteration without incurring retooling costs — which can range from $25,000 to $100,000.
• Supply Chain Efficiency
  It’s estimated that companies leveraging on-demand additive manufacturing can achieve total supply chain savings as high as 50 to 90 percent. Especially for companies selling large quantities of replacement parts, on-demand additive manufacturing opens up opportunity to eliminate warehousing costs and reduce the risk of part obsolescence.
• Faster Product Iteration
  AM allows design teams to refine and optimize their product with each design iteration. And because you’re prototyping on the same machine your product will be produced on, you can begin to validate the manufacturing process and your product’s performance during the prototype stage. In some instances, the time it takes to go from initial product concept to final product design can be reduced by up to 90 percent.

There are many benefits to making the switch to AM, but of course there are challenges to consider. Producing a part through AM may mean you’re paying a higher per-part cost than conventional manufacturing. However, those fees can be offset because AM also virtually eliminates the need for warehousing, which is critical because housing inventory can add anywhere from 20 to 25 percent to overall costs of production. Contact us today to learn more.

The post Beyond Prototyping: Scaling Up to Additive Manufacturing for Production appeared first on SyBridge Technologies.

If you take apart a well-made plastic component, you’ll notice the walls are uniform all around. Maintaining a uniform wall thickness is one of the most important rules of injection molding design, and it can determine the success or failure of a part. What is uniform wall thickness, and why is it so important for production? Let’s dive into it.

The importance of maintaining a uniform wall thickness

Uniform wall thickness means that all the walls of a part are of the same thickness. There are many manufacturing advantages to keeping your part’s wall thickness uniform throughout. One such advantage is that uniform wall thickness promotes consistency part-to-part, which decreases the time required to mold each part for both high and low-volume injection molding production runs. Uniform wall thickness also prevents errors upfront that could waste time and resources, improves a part’s stress distribution, uses less material to decrease costs, and minimizes shrinking post-production.

It’s important to ensure uniform wall thickness when injection molding, not only to promote better parts and more streamlined production. There are a whole host of issues that can occur if your walls aren’t uniform:

• Warping — Twists and bends in a part’s shape that stem from uneven shrinkage due to a lack of wall thickness uniformity.
• Flow lines — Lines or waves that appear because of different flow rates as the molten material fills the injection mold cavity.
• Sink marks — Small craters that occur when the molten plastic can’t cool completely in the mold. Sink marks often form on the thicker parts of uneven walls.
• Short shots — Some sections of a mold can be missed during the injection molding process due to uneven wall thickness. Uneven walls can prematurely cool plastic flowing from a thin section to a thick section, which prevents the thicker section from getting any molten material at all.
• Gating challenges — Gating systems ensure smooth and even filling of the molten material in the mold. Uneven walls can cause molten material to flow from thin to thick sections, instead of thick to thin. This causes the material to cool in the thinner wall section and block the flow to the thick section.
• Cooling rate issues — Cooling rates can be compromised by uneven wall thickness because certain sections will take different amounts of time to cool. This can increase manufacturing and process times and also render some individual parts unusable.

Being diligent about enforcing uniform wall thickness can help prevent these complications and other defects from arising before, during, and after a part’s production cycle.

How to avoid uneven walls

Before you make sure all of your part’s walls are even, you have to determine the proper wall thickness for the part. Finding the best wall thickness can be tricky — your walls must be thick enough to support the intended load of a part without compromising the production and final functionality of your component. Here are some good rules of thumb:

• General wall thickness should be between 1.2mm and 3mm, although some variation based on materials is expected.
• Overall, wall thickness should stay below 5mm because thicker walls lengthen production cycle times and could negatively affect functionality and aesthetic appeal.
• Adjacent walls must not be less than 40 to 60 percent the thickness of the other.

Thicker walls bring mechanical strength to the table, but thinner walls have a wider range of benefits. Thinner walls use less material, cost less, and are quicker to manufacture. Thin, uniform walls are also more resistant to warping during cooling and take less time to cool. This further increases the efficiency of your production run. After production, components with thinner walls are easier and less expensive to manage, handle, and ship because they are physically lighter.

Build better parts with SyBridge

The importance of uniform wall thickness cannot be overstated, especially when it comes to injection molded parts. By making sure that your part has uniform walls throughout, you can promote streamlined production runs that produce consistent components. Uniform wall thickness can also prevent cosmetic and performance issues, which lengthens the lifespan of each individual part.

At SyBridge, we can help you ensure uniform wall thickness and avoid injection molding design mistakes. Starting with design and material selection, moving all the way to production and post-production processes, our team of experienced manufacturers can help you improve operations and reduce costs. To get started on building uniform and high-quality components, contact us today.

The post Why is Uniform Wall Thickness Important? appeared first on SyBridge Technologies.

Product development is a constantly evolving process, and you might not get it right on the first try. Don’t worry — some amount of this is to be expected. If and when a part fails or doesn’t perform as anticipated, you want to find out as much as you can about the failure so you can learn from past mistakes and make better products. That’s where failure analysis comes in.

What is failure analysis?

Failure analysis is the process of investigating product failures in order to troubleshoot and repair the underlying issue. Failure analysis can help pinpoint the specific stages or operations where different problem types arise and provide a framework for establishing internal processes to counteract these opportunities for error. This helps identify discrepancies and other inaccuracies early on, allowing you to refine your part designs while it’s still economical to do so.

Once you’ve identified precisely what’s giving you trouble, the next step is to take appropriate corrective action in order to prevent the problem from reappearing during subsequent production cycles. Robust failure analysis practices not only help to avoid future product failures but also provide a number of other benefits.

• Failure analysis allows you to get to the root cause of the problem. This involves collecting data metrics to determine whether the material, manufacturing process, misuse, or something else is at fault.
• It minimizes potential risks to product teams and the production environment.
• It helps improve financial outcomes by avoiding costly setbacks caused by failed part components. Outages, production stoppages, and litigation can all significantly increase your costs. Failure analysis processes help to address these concerns, meet industry and regulatory standards, and determine fault liability, as well.

Failure analysis strategies in manufacturing

The basic process of failure analysis is fairly straightforward — identify and document the problem, analyze the data, and refine your designs based on those findings. However, each of these steps can become complicated when translated into practical terms. Let’s break them down in more detail.

When an error occurs, the broken part samples should be collected, rather than discarded — that’s the evidence you’ll be documenting and analyzing. It’s important to establish clear guidelines as to who will receive part samples that break, are nonfunctional, are involved in safety events, etc. Likewise, sufficient resources, technical expertise, and testing equipment need to be allocated. Using checklists and logistics solutions can help to minimize human error, as well.

The next step is to document the symptoms or process issues and to come up with test criteria that will allow you to detect the underlying problem in the development build. Documenting the symptoms of the failure can often serve as a light round of preliminary analysis. You might organize part samples by the type or mode of failure (electrical, mechanical, etc.), whether the part is still functional but has reduced capability, whether the issue is cosmetic, or whether the symptom is a common problem typically caused by unoptimized part designs or manufacturing issues. Creating a body of documentation also makes it easier to identify repeat problems across disparate batches and processes.

Critical junctures, the process steps that alter the form or function of a part or that expose it to damage, should be monitored especially closely. It’s also helpful to team members to describe the events leading up to the failure or issue, including environmental conditions like temperature and humidity, or anything out of the ordinary. This sort of contextual information can be essential for troubleshooting reliability and quality issues. You should also document the manufacturing batch the failed piece is part of in case of a recall.

The next phase of root cause failure analysis involves isolating each potential factor to test whether it is at fault. Once the underlying cause has been determined, you should be able to develop and implement an effective troubleshooting plan. Documenting your steps and the results in a database can often come in handy down the line, as well.

Things to consider when performing engineering failure analysis

Here are some questions to ask during the failure analysis process:

• What kind of failure is it?
• How critical is the failure?
• Can the failure be repeated in future parts?
• Are there other potential contributing factors?
• Will your solution impact other teams or processes in the pipeline?
• What steps can you take to prevent the issue from recurring?

Product failures that cause serious safety issues are the most urgent to respond to, and there should be contingency plans in place for these scenarios. If the failure is not causing severe safety concerns, then you likely have more time to work out a proper course of corrective action. This can mean going back to the drawing board and prototyping new parts to demonstrate how the suggested improvements will benefit customers and manufacturers alike.

Improve your manufacturing process steps today

Failure analysis is key to understanding what went wrong during production, what caused the problems, and how to prevent issues in the future. Failure analysis helps turn mistakes and errors into learning opportunities so that you can refine your development processes based on past experiences.

While product teams can start investigating failures on their own, they’ll need a manufacturing partner to perform in-depth failure analysis. SyBridge Technologies can help. Our team of engineers and designers specialize in establishing efficient production processes and detailed documentation — in addition to ensuring that each job is carried out as efficiently as possible. Contact us today to learn more about how we can help make your designs a reality.

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Finite element analysis, also known as FEA, is the virtual simulation of a physical component using a mathematical technique called the Finite Element Method (FEM). The roots of FEA date back to the sixteenth century, and the first true use of FEA dates back to Schellback’s work in 1851. For the next hundred years, FEA was primarily used by mathematicians and other scholars. With the advancement of digital computers, real-world developments of FEA began to pop up within the automotive, aerospace, and civil engineering industries.

FEA can now reach more users than ever. Today’s finite element analysis software is intuitive to use, accessible across electronic devices, and incredibly fast and powerful. To discover more about what FEA is and how it works, keep reading.

What is Finite Element Analysis?

FEA is the process of creating a digital simulation of a soon-to-be-real product. While finite element analysis once required you to put pencil to paper, nowadays FEA takes place in a computer program’s virtual environment. FEA computer-based software can virtually model complex geometries and components, enabling scientists and engineers to better predict how these products will perform in real life.

In the design and manufacturing process, FEA can help you understand a part’s physical properties — such as its impact resistance, thermal elements, and transient dynamics — to predict its strength, movement, and other behaviors. FEA can also envision the characteristics of a particular material under specific conditions like deflection, vibration, and other stressors. Through these predictions, FEA enables you to identify potential performance issues and find solutions before the component is created.

There are different types of finite element analysis, including:

• Thermal Engineering Analysis: Determine how temperature variations will impact part performance
• Fluid Dynamic Calculations: Understand the structural impact of a fluid’s density, a trait especially important in the oil and gas industry
• Engineering Seismic Calculations: Predict part performance under various ground vibrations and frequencies
• Modal Analysis: Anticipate how external forced vibrations, such as wind or travel speed, affect part performance
• Linear Static Analysis: Apply linear proportions of a small-scale model to the full-sized structure to anticipate scenarios

How Does Finite Element Analysis Work?

Finite element analysis is an incredibly mathematical process, so we’ll explain it in layman’s terms. Simply put, FEA breaks down a complex structure into smaller and more manageable portions. As you split the structure into smaller sections, you will gain more knowledge of how the larger structure will respond to stressors.

The first step of the FEA process is to determine the placement of nodes on the structure, which are single points on a 2D or 3D rendering of your design. After selecting your nodes, or nodal points, connect them by drawing lines between them. This will create a mesh structure that forms the final shape of the design. The regions enclosed by the mesh contain a collection of finite elements, which is where the name “finite element analysis” comes from.

By tackling the small sections that make up your structure’s mesh, you can more precisely determine how the entire structure will act in given circumstances. Note that the more dense your mesh structure, the more precise your results will be, but your computations will increase in complexity as you add nodal points.

How is Finite Element Analysis Used in Manufacturing?

In manufacturing, FEA is used to determine a component’s potential responses to external and internal physical stressors. Finite element analysis software is built to take part geometry, material, environment, and other factors into account when virtually testing your FEA simulation. This enables you to predict how a component will perform under expected and unexpected conditions.

Since FEA exists in a virtual world, it can significantly streamline the prototyping process. Instead of having to build prototype after prototype, FEA enables you to easily test a component many times and make changes between iterations. This saves you time, resources, costs, and effort when designing a component. FEA software is designed to be as realistic as possible, enabling these powerful programs to accurately anticipate part performance.

Rapid virtual prototyping supported by FEA is especially important in the aerospace industry. Because aerospace components must survive the extreme stress of outer space — such as air pressure, inertia, impact forces, and super-high heat — it’s critical that they follow very strict manufacturing guidelines. Using FEA, you can accurately anticipate how a component will react to these extreme conditions. FEA can also predict years or even decades of use, a helpful tool for aerospace components that could be in orbit for many years.

Throughout the manufacturing process, FEA allows you to save time and money, reduce energy and material waste, and gather instant and accurate feedback on how physical stress could affect your component. Overall, FEA contributes to a quicker, less intensive design cycle with increased productivity.

Finite Element Analysis With SyBridge

Finite element analysis is a specialized field. At SyBridge, we have experts on hand who will use FEA to optimize your part designs. By leveraging accurate finite element analysis, our team can help you improve your parts and perfect your production runs. Contact us today to get started with FEA.

The post A Beginner’s Guide to Finite Element Analysis (FEA) appeared first on SyBridge Technologies.

Nobody’s perfect, and neither are manufactured components. Manufactured parts naturally have minute variations due to the inconsistencies that occur in the manufacturing process. We can’t eliminate them entirely, but we can control and account for these variances.

Engineers use geometric dimensioning and tolerancing, often shortened to GD&T, to communicate a part’s design requirements and their acceptable deviations. GD&T works through a series of symbols, but what exactly do geometric dimensioning and tolerancing symbols mean? And why is GD&T important at all? We’ll go over all the GD&T basics and more in this article.

What is GD&T?

GD&T is a system of symbols, characters, and standard dimensions intended to communicate design intent between engineers and manufacturers. GD&T defines a part’s features and its allowable deviation from its true or ideal position. The general goal of GD&T is to highlight the most important features of a part and demonstrate how those features connect to the bigger picture.

GD&T covers the geometric dimensions of a component as well as its tolerance values. A part’s tolerance specifies the minimum and maximum limit of deviation for a specified dimension. Creating proper tolerances will maximize the product approval rate and increase the amount of properly machined parts. Tighter tolerances are more precise but can raise production costs, so product teams should create tolerances with as much leeway as possible while maintaining product functionality.

GD&T is essential to manufacturing precise and functional parts, plus it enables anyone to read and understand a component’s dimensions. GD&T follows the same process across manufacturing methods, from additive manufacturing to CNC machining to injection molding. However, certain aspects of GD&T will be more relevant for some methods than others.

GD&T characteristics

Before we dive into GD&T symbols, we have to go over the Datum Reference Frame (DRF). DRF is the 3D coordinate system on which GD&T dimensions live. A datum itself is typically a point, line, or plane on the DRF used as the starting mark for measurement. A datum feature is the actual physical element itself. Put more simply, the datum is the ideal, perfect dimension whereas the datum feature is the real, naturally variant component element.

GD&T symbols cover dimensions and tolerances as well as shape, size, and other aspects of a part. By communicating design intentions, GD&T symbols help ensure the part is made exactly how it should be. This ensures the component will fit the role it’s designed for, match up with any mating parts, and remain consistent with its fellow components.

There are five different groups or “tolerance types” with geometric characteristics in each one:

• Form specifies shape and refines the size of a part. A part’s form can be described according to straightness, flatness, circularity, or cylindricity. Form does not use a datum reference.
• Orientation controls the tilt of a part’s surface, axes, or median planes. A part’s orientation can be described according to angularity, perpendicularity, or parallelism. Orientation tolerances require a datum reference.
• Location describes the center point, axis, or median plane of a feature. A part’s location can be described according to concentricity or symmetry, which are derived from a feature’s median point. Location can also describe a part’s position that is oriented around a size feature’s center point, axes, and median planes. Position also controls orientation.
• Runout controls a circular part’s surface coaxiality, which indicates how much a feature can vary with respect to its datums. A part’s surface can be defined according to total runout or circular runout, both of which control the surface’s form and orientation. Total runout is used to control the angularity and straightness of your design’s entire surface, while circular runout is used to account for a wide variety of different errors.
• Profile specifies the tolerance zone around a specific surface, which controls a surface’s size, form, and orientation, and is often based on a datum reference. You can define a part’s line profile or surface profile.

Understanding the Feature Control Frame

Another important part of reading GD&T is understanding the Feature Control Frame. Feature Control Frame symbols show how everything defined with GD&T fits together. In the frame, you’ll see a symbol followed by an allowable tolerance, as well as any Feature Control Frame modifiers for part design. This enables machinists and manufacturers to make adjustments based on where other features need to go.

Each Feature Control Frame contains only one message or design requirement. This means if a feature requires two messages, you’ll need two feature control frames to communicate design intent through GD&T. A GD&T Feature Control Frame has up to five compartments: the first compartment contains one geometric characteristic symbol, which dictates the part requirements.

The second compartment relays the total tolerance of your design, and an “ø” symbol preceding the tolerance value indicates a cylindrically-shaped tolerance zone with a diameter of the indicated value. The third, fourth, and fifth compartments contain the datum reference features, if they are necessary. Usually, the datum feature defined in the Feature Control Panel indicates how the part interacts with or assembles to mating parts or which features are most critical to functionality.

The Feature Control Frame compartments may also contain material condition or material boundary modifiers, which inform the size and specifications of the feature or datum, allowing for even greater ease of manufacturability when used correctly. These sections give manufacturers insights into how precise they need to be when following the given GD&T data. By clearly communicating part features and requirements, the Feature Control Frame defines measurements’ allowable variance in order to build functional components.

GD&T benefits and guidance

There are many benefits to using GD&T in your part designs. Primarily, GD&T provides clear communication between manufacturing vendors, designers and engineers, and quality inspectors. Describing product geometry by its intended functionality and manufacturing approach is simpler than describing all of a part’s characteristics in linear dimensions.

Since GD&T symbols can capture the dimensions for non-linear features, GD&T data helps paint a complete picture of your component. You can also increase your tolerance knowledge for improved control features, such as curves. Optimizing part tolerances makes a component easier to manufacture and maintains reliability and consistency between individual components.

Defining GD&T data helps ensure separate parts will fit together and work properly. However, there are some guidelines and considerations you should keep in mind when creating and implementing GD&T data.

Be conscious about your datums. Choosing reference datums that are easy to measure from will ease manufacturing.

Balance your tolerances. Think about how precise a specific part feature needs to be and adjust the tolerance accordingly to save costs and streamline manufacturing. Make sure your tolerances are in machineable limits, follow given standards, and account for tolerance stacking. Since parts interact at their final assembly, make sure the GD&T requirements per part are within the allowable stack up of the interfacing assembly when combined.

Don’t over-dimension your part. An unclear part drawing defeats the purpose of GD&T, which is to clarify and streamline communication. Over-dimensioning could make your part design harder to understand and your components harder to manufacture, plus conflicting dimensions can accidentally bring errors into your parts. Be judicious and intentional about which features you’re calling out in your GD&T design and only highlight the necessary information or “critical interfaces” of your component.

Optimize GD&T with SyBridge Technologies

Creating clear, understandable GD&T designs is critical to ensuring your parts come as close to perfect as possible. However, it can be difficult to manage all the moving parts of GD&T and ensure clarity, consistency, and precision throughout your component designs. Working with a seasoned manufacturer can help you optimize your GD&T designs, streamline production runs, and create better parts.

At SyBridge Technologies, we can guide you through the GD&T process from start to finish. Our team of experts has in-depth knowledge of the fundamentals of geometric dimensioning and tolerancing, and we’ll help you design parts using the right standards and symbols to promote part accuracy. To bring expert GD&T to your next part design, contact us today.

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