Jigs and fixtures are often made with custom parts from Xometry. Both of these devices help engineers and manufacturers to make better products.
A jig is a device that helps support, hold and locate a workpiece by guiding the tools that are needed to execute a manufacturing operation. Well-made jigs can have a major impact on the repeatability and accuracy of a manufacturing process. Jigs are used in uni-dimensional processes like drilling, tapping and reaming. Jigs also can have installed components, like bushings, which can come into contact with the cutting tool. An example is a drill bushing, which keeps drills in the right position and at the right angle to perform their work. 3D printing jigs is common practice due to the process ability to create conformal shapes and off-angle features without expensive tooling and setups.
Unlike jigs, which help to guide tools, fixtures help to hold workpieces in position so that they can be machined accurately. Examples include blocks of raw materials fixed inside machines and vices or clamps that hold workpieces in place. Most manufacturing facilities use fixtures to enable automation to increase production speed. For example, Xometry builds automotive fixtures for BMW that are used for aligning a vehicles front end during assembly. This helps BMW to manufacture their vehicles more efficiently and reduce operational error though repeatable work holding and installation solutions. BMW uses 3D printing services, urethane casting and CNC machining services to produce custom fixture assemblies.
Jigs and fixtures are both used to increase the productive time of mass production processes. But there are key differences between the two. Jigs always help guide a tool, while fixtures hold and locate the work, but do not guide tools. Fixtures are usually heavier and are bolted directly to the machine table, while jigs are usually lighter and are not affixed directly to the table. Jigs are also generally more complex to design and more expensive to produce than fixtures.
Both jigs and fixtures can be made with CNC Machining or 3D Printing, though it is more common to see 3D printed jigs since they are lighter. 3D printing can be a great choice with parts with complex geometries since they can often be expensive or challenging to machine. 3D printed jigs can be significantly cheaper than machined ones, so its worth getting a quote in 3D printing as part of your process.
Designing a fixture or jig begins with the application in mind as well as the quantities needed. There are three main processes used when making jigs or fixtures.
1. CNC machining is great for producing low to medium complexity shapes that require high stiffness, extreme environments and precision tolerances. Delrin (Acetal), Garolite, PTFE and PEEK are the most common polymers used for machining jigs and fixtures. In metal, typically Aluminum 6061-T6 is the most common, which can be enhanced by finishes like metal plating, color anodizing and chemical conversion coatings. CNC milling is the best approach for quality check fixtures, due to its ability to achieve precision tolerances and surface finishes.
2. Additive manufacturing or 3D printing can produce low to very high complexity shapes with ease. Fused Deposition Modeling (FDM) is heavily used in making fixtures because of a build area up to three feet and the ability to make lightweight parts using sparse infill. Handheld jigs, such as surgical drill guides, may utilize processes like Carbon DLS or Stereolithography due to a good combination of precision and durable parts. PolyJet 3D printing is useful for laser marking fixtures because of its ability to produce soft-touch, non-marking holders using multi-material 3D printing, similar to a rubber overmold.
3. Urethane casting combines the design freedom of 3D printing with high-wear, urethane-based materials. Urethane casting can produce low volume production parts that can be color-matched, hit a specific durometer and are non-marring for holding finished products and ornamental pieces. Cast urethane parts are often flexible or rubber-like but can also be highly stiff depending on the material used.
Each jig or fixture is custom, and specifically designed for its application. There is no right way to make or combine parts together but there are best practices that will help guide your thought process. The tips below aid in design best practices for fixtures and jigs.
1. Make a mockup if you do not have the part yet. 3D printing is by far the best means to get a rapid prototype of a part to be fixtured. Even before the design process, a physical model to reference can be a powerful tool to inspire a design approach. 3D printed parts can also be robust enough to trail fixture or jig setups, including drilling, part marking and running automated inspection like CMM.
2. Limit your touchpoints in the design to those which critically support the object as well as indicate or index its orientation. This will reduce the complexity of the jig or fixture and save headaches when the digital design meets realitywhere minor deviations may occur from manufacturing.
3. Give clearances to corners and bends when designing conformal jigs and fixtures. Many manufacturing processes may have small radii in sharp internal corners. Instead of risking an interfering fit, it is best to design generous pockets or clearances around those features. For fixturing bent tubing or sheet metal components, it is best to design for the maximum condition of the curve or avoid touchpoints in that area altogether. This is due to deviations from the CAD which can often occur in the bent or formed locations.
4. Split up large parts to reduce manufacturing costs and increase the flexibility in the design. For example, you can build a 30 fixture, but it may be 2-3X less expensive to build smaller components only where the touchpoints are requiredespecially if the fixture will be mounted to a threaded plate.
5. Make the parts lightweight by using ultralight or sparse infills with FDM, or by designing features like pockets, ribs and holes to reduce the material used. This is particularly useful for jigs, where it is very common they will be handheld. Lighter parts will reduce fatigue over time and can be easier to store between uses.
6. Mix materials and processes to get a specific function out of the jig or fixture. It is not uncommon to see 3D printed components cover the highly custom contours of a jig or fixture while other features are generated using precision milling or other processes. Each process has its strengths and trade-offs, and with manufacturing as a service models (MaaS) like Xometry there are very few restrictions to what process and materials can be used.
7. Use COTS frequently to reduce costs on standardized components like handles and clamps. COTS stands for commercial off the shelf and is a catch-all term for anything you can buy without needing to custom design it (screws, pins, handles, rails, etc.). COTS components are almost always cheaper than custom manufactured pieces, often by orders of magnitude in costs. The custom components machined, cast or additively manufactured should be specific to the application need. Adding threaded inserts or tapped holes to the custom components prepares them for custom COTS integrations.
8. Prepare for benchtop adjustments by incorporating adjustable features. For example, metal shims between screw-mounted components are extremely common to compensate for tolerance deviations in assemblies. Using slots for table top-mounted fixtures allows minor adjustments to be made without heavy rework. Spring-powered pogo pins, whether custom or off-the-shelf, are also useful for giving firm mounting while allowing for small deviations between parts.
With online machine shops and online 3D printing services available today, it has never been easier to produce single and low volume custom jig and fixtures. Xometry has the benefit of providing the most common services and materials used for producing custom guides and work holding solutions with short lead times and low costs. Xometry can even build custom assemblies on-demand as it does for BMWs automotive line. Getting started is easy by uploading the 3D models for the jig or fixture to Xometrys Instant Quoting Engine.
This article was published in collaboration with Xometry.
Read more from the original source:
Jigs and fixtures by Xometry - 3DPMN
- Make Money from Images, Documents and Photos Uploading - December 18th, 2016 [December 18th, 2016]
- Immortal but Damned to Hell on Earth - The Atlantic - January 29th, 2017 [January 29th, 2017]
- Hands on review: Zencastr podcast maker - The Sydney Morning Herald - February 7th, 2017 [February 7th, 2017]
- How to keep your children safe online as it's revealed half of six-year-olds use the internet - Mirror.co.uk - February 7th, 2017 [February 7th, 2017]
- Yetunde Olasiyan: Between Having a Voice & the Need to Show Off on Social Media - Bella Naija - February 7th, 2017 [February 7th, 2017]
- How a WiFi Pilot Program Is Helping Students in the Rio Grande Valley - KUT - February 7th, 2017 [February 7th, 2017]
- These Shows Understand Why TV Cannot Survive Without The Internet And They're Doing Something About It - Decider - February 8th, 2017 [February 8th, 2017]
- 10 reasons to not miss John Bender at El Club this weekend - Detroit Metro Times - February 8th, 2017 [February 8th, 2017]
- Ideal Flatmate promises to stamp out all roommate worries - The Tech Portal - February 8th, 2017 [February 8th, 2017]
- Five ways to ensure your kids are safe as they go 'online' - The Standard (press release) - February 8th, 2017 [February 8th, 2017]
- How to improve your LinkedIn profile - ArabianBusiness.com - February 9th, 2017 [February 9th, 2017]
- Deal: New customers can get Google Play Music and YouTube Red free for 4 months - Android Authority (blog) - February 10th, 2017 [February 10th, 2017]
- Breaking Down Global Silos (Part 2): Lessons Learned from Conflict - Spend Matters - February 14th, 2017 [February 14th, 2017]
- Issa Rae New Series Giants Is A Must Watch - CampusLATELY (blog) - February 15th, 2017 [February 15th, 2017]
- Fake news, who benefits? - Shelbyville Times-Gazette (blog) - February 16th, 2017 [February 16th, 2017]
- GST beneficial for traders, says official - The Hindu - February 16th, 2017 [February 16th, 2017]
- It's time to get tech-savvy with The Mind Lab by Unitec! - Scoop.co.nz - February 16th, 2017 [February 16th, 2017]
- 'Being an Irish author is more of a Grimm fairytale than a Cinderella story' - Irish Times - February 17th, 2017 [February 17th, 2017]
- Barbie becomes a hologram version of herself - TechCrunch - February 18th, 2017 [February 18th, 2017]
- PLYMOUTH BUSINESS EXPANSION: MycomPETibility.com goes nationwide - Wicked Local Kingston - February 20th, 2017 [February 20th, 2017]
- The three reasons YouTubers keep imploding, from a YouTuber - Polygon - February 22nd, 2017 [February 22nd, 2017]
- SnailBlitz 2017: Citizen Scientists Wanted - NBC Southern California - February 22nd, 2017 [February 22nd, 2017]
- Nikon D5600 Review: Hoping to Make Photo Transfers a Snap - Huffington Post - February 27th, 2017 [February 27th, 2017]
- Appealing Social Security Decisions Online - CBN News - February 28th, 2017 [February 28th, 2017]
- How to file your social security appeal online - WZZM13.com - February 28th, 2017 [February 28th, 2017]
- Meteor is OpenSignal's own speed test app - SlashGear - March 1st, 2017 [March 1st, 2017]
- Data limits are the worsthere's how to stay under yours - Popular Science - March 3rd, 2017 [March 3rd, 2017]
- Overcome problems with public cloud storage providers - TechTarget - March 3rd, 2017 [March 3rd, 2017]
- When Words Beget Blows - Outlook India - March 4th, 2017 [March 4th, 2017]
- A man with vitiligo who was called 'zebra' by bullies has defied their cruel comments by becoming a model - The Sun - March 8th, 2017 [March 8th, 2017]
- Shark Tank's Robert Herjavec coaches kids to fuel entrepreneurial spirit - VentureBeat - March 9th, 2017 [March 9th, 2017]
- Everything new in Stellaris: Utopia, one of Paradox's biggest game updates ever - PC Gamer - March 10th, 2017 [March 10th, 2017]
- IN TRANSIT: The Idol Maker - Mumbai Mirror - March 11th, 2017 [March 11th, 2017]
- Paytm to continue free uploading of money - Business Standard - March 11th, 2017 [March 11th, 2017]
- The perils and false rewards of parenting in the era of 'digi-discipline' - Minnesota Public Radio News - April 8th, 2017 [April 8th, 2017]
- Showtime docu-series sees the 'Dark' side of tech - LA Daily News - April 8th, 2017 [April 8th, 2017]
- Elon Musk: Australian man pens desperate letter to download his brain - NEWS.com.au - April 8th, 2017 [April 8th, 2017]
- How Vestas Wind Systems used outsourced machine learning to transform contract management - Diginomica - June 7th, 2017 [June 7th, 2017]
- Wednesday Web Artist of the Week: Eva Papamargariti - ArtSlant - June 7th, 2017 [June 7th, 2017]
- Your Obsolete Brain: Life and Death in the Age of Superintelligent Machines - Digital Journal - June 7th, 2017 [June 7th, 2017]
- Under Armour launches its first customisable shoes - just-style.com (subscription) - June 8th, 2017 [June 8th, 2017]
- I Don't Care What You Think, I Love My Facial Birthmark - SELF - June 9th, 2017 [June 9th, 2017]
- Cable: Where Are We Headed After This Political Meltdown? - Seeking Alpha - June 9th, 2017 [June 9th, 2017]
- Best Screen Recorders Top 10 Screen Capture Software - Gazette Review - June 10th, 2017 [June 10th, 2017]
- Nigeria just got a verified Twitter handle - TechCabal - June 12th, 2017 [June 12th, 2017]
- Just keep pinning: why your business should be on Pinterest - Cambridge Network - June 12th, 2017 [June 12th, 2017]
- Track-by-Track of Paramore's 'Riot!' Read Through Emo Teen Memories - Noisey - June 13th, 2017 [June 13th, 2017]
- Decision day for Go Forward Pine Bluff - Pine Bluff Commercial - June 13th, 2017 [June 13th, 2017]
- Addressing rape culture - News24 - June 14th, 2017 [June 14th, 2017]
- Italy's Samantha Cristoforetti Says Being a Good Astronaut is All About Teamwork - Fortune - June 16th, 2017 [June 16th, 2017]
- Google Drive will soon make it easy to Backup and Sync PCs, Macs - SlashGear - June 16th, 2017 [June 16th, 2017]
- What's worse than getting phished? Getting phished *and* sending a selfie of your Photo ID and credit card - Graham Cluley Security News - June 17th, 2017 [June 17th, 2017]
- Track Of The Day 16/6 - Maximillian - Clash Magazine - June 17th, 2017 [June 17th, 2017]
- AROUND TOWN: GOP chairman questions Ossoff's London office - MDJOnline.com - June 20th, 2017 [June 20th, 2017]
- RESEARCH & TECHNOLOGY/INNOVATION: ITS Fiber brings fast connections, data center services to local business - TCPalm - June 20th, 2017 [June 20th, 2017]
- Fiberlink Internet Packages & Prices 2017 - TechJuice (press release) (blog) - June 20th, 2017 [June 20th, 2017]
- CS Editors: Creating Content - Security Sales & Integration - June 20th, 2017 [June 20th, 2017]
- How to post a GIF to Facebook - Tech Advisor (registration) - June 21st, 2017 [June 21st, 2017]
- The Living Vampire / Real Vampire FAQ (Frequently Asked Questions) - HuffPost - June 21st, 2017 [June 21st, 2017]
- Facebook Is Introducing New Tools to Protect Women in India - Fortune - June 21st, 2017 [June 21st, 2017]
- Mum drops off daughter at college then sends her hilarious texts with football team - NEWS.com.au - June 22nd, 2017 [June 22nd, 2017]
- Is Chrome OS right for you? A 3-question quiz to find out - Computerworld - June 22nd, 2017 [June 22nd, 2017]
- Facebook wants to stop creeps from downloading your profile picture - TNW - June 23rd, 2017 [June 23rd, 2017]
- Action and Emotion - lareviewofbooks - June 26th, 2017 [June 26th, 2017]
- 6 ways to be more hirable and 1 that could land a job today - Deseret News - June 27th, 2017 [June 27th, 2017]
- Searching for a Career? Set up a Free Profile at AutoCareCareers.org - PR Newswire (press release) - June 27th, 2017 [June 27th, 2017]
- Industry Job Seekers Can Set Up A Free Profile At AutoCareCareers.Org - AftermarketNews.com (AMN) - June 29th, 2017 [June 29th, 2017]
- Steve Mitchell The Mind of Watercolor Blog - June 29th, 2017 [June 29th, 2017]
- How to Upload to Google Drive - Cloudwards - July 1st, 2017 [July 1st, 2017]
- Stevie Ryan, YouTube personality, found dead at home - Blasting News - July 4th, 2017 [July 4th, 2017]
- 5 tips to a delicious food photo - Orlando Sentinel - July 5th, 2017 [July 5th, 2017]
- Gordon Hayward the best Jazz wing player of all time? Not what the numbers say. - SLC Dunk - July 5th, 2017 [July 5th, 2017]
- 36 Years of Loretta's - Racer X Online - July 6th, 2017 [July 6th, 2017]
- How to Work on Your Laptop at a Coffee Shop Without Being a Jerk - Lifehacker - July 8th, 2017 [July 8th, 2017]
- There's a new most-viewed Youtube video, pushing Gangnam Style off the top spot - Buzz.ie - July 12th, 2017 [July 12th, 2017]
- How to prevent bandwidth throttling with a VPN - T3 - July 14th, 2017 [July 14th, 2017]
- Google will now let you back up your entire computer for FREE on its servers - Mirror.co.uk - July 15th, 2017 [July 15th, 2017]
- Google Drive Backup and Sync lets you backup your entire computer: Here's how it works - BGR India - July 17th, 2017 [July 17th, 2017]
- Why Mythology Still Matters: Wisdom from Game of Thrones' 'Dragonstone' - Big Think - July 17th, 2017 [July 17th, 2017]
- Mum somehow manages to convince her daughter her nipple's fallen off in hilarious text exchange - Metro - July 18th, 2017 [July 18th, 2017]