diy 5th axis cnc rotary table in stock

Whether you use mills, presses or lathes, machine tools are often only as useful as the accessories that come with them. Take care of repair tasks and add extra functionality with the machine tools accessories at Alibaba.com. If you need new 5 axis rotary table or are seeking to replenish your component stocks, our wholesale store is the ideal place to look. We stock accessories for every type of machine tool, with multiple options in most cases. So add resilience to your operations and be ready for any production challenge with the machine tools accessories in our store.

Machine tools come in all shapes and sizes, and so do the accessories that make them tick. For instance, CNC and manual lathes can be customized with jaw chucks, shanks, woodworking knives, drill chucks, rotary chucks, clamps, and turning tools. Add brushes and sanding discs, and turn your machine tool into a multi-purpose machining center. Add a range of cutting tools to milling machines, pick the right drum sanders for your drills, or add a lathe dog to make turning much easier. There are accessories for hydraulic presses, add-ons like drag chains, and many other machine tools accessories. And if you need replacement 5 axis rotary table, Alibaba has everything you need.

Our machine tools catalog is packed with accessories. Search the listings for your preferred tool and zero in on accessories that can enhance its functionality. From control handles to tool holders, thread holders and saw blades, the whole panorama of machine tools accessories is here and ready to order. There"s no better way to add extra stocks and renovate machinery when the time comes. When new 5 axis rotary table are required, head to the Alibaba wholesale store and give your machinery a new lease of life.

NIKKEN’s world-renowned CNC Rotary Table range provides proven performance, reliability and accuracy benefits for any application or requirement that others simply cannot hope to emulate.

With an extensive range of rotary table sizes, configurations and options available, all fully supported by our extensive global network, you can be sure to find the perfect product to meet any requirement or machine tool.

Single Axis, Twin Axis, Multi-Spindle, Standard Drive, High-Speed Drive, and Direct Drive capabilities are all available from stock. These can be configured and supplied for control directly by the CNC Machine or by integrating our exclusive Alpha 21 and EZ controllers to provide precise positioning and also full Macro B control (Macro B function – Alpha 21 only).

NIKKEN can also provide a complete and expansive range of accessories precisely engineered and customised to suit both the machine tool and the component. These options include a wide variety of chucking solutions, vices, bespoke trunnions & workpiece fixturing along with a wide range of NIKKEN manufactured rotary work supports and tailstocks to cater for all production expectations.

KME CNC Rigid Cast Iron Trunnion Tables are one of the leaders in the industry for accuracy, surface finishes and repeatability.  Allowing you to speed up your cycle times, these tables are ideal for high volume production applications. Powerful and compact trunnion design ensures smooth operation over the entire travel range.

Because the tilting axis normally needs to bear a heavy load, a robust transmission mechanism for the tilting axis should be employed to improve the wear resistance and precision of the tilting axis. Thus, we can provide roller gear cam, alloy steel worm gear, or Japanese- made worm & worm gear (wear life is 2.6 times longer than aluminum bronze PBC3.) as the transmission mechanism of the tilting axis.

At Hosea Precision, quality comes first - at every stage of the production process. We are dedicated to producing 5 axis and 4 axis rotary tables, which are two of our proudest products. With the high-quality and precision feature, our CNC rotary tables have been sold & widely used in the European market and have an enormously high reputation amongst our customers.

In March 2015 Hosea Precision created the independent brand, to make it a household name for high-quality 4 axis rotary tables from Taiwan. We have been following this strategy with great success: more and more manufacturers across Europe cooperate with us and make use of our 5 axis rotary tables and other rotary tables products. Do not hesitate to contact Hosea for more products detail!

Centroid OEM Machine Tool Manufactures offer a wide variety of Centroid CNC equipped machine tools.. click to to find a Centroid equipped CNC machine tools..

Small Milling Machine CNC Control system: $18,385M400 3 axis with 1Kw AC Brushless Yaskawa servo motors and drivesMedium Milling Machine CNC control system: $22,175M400 3 axis with 2Kw AC Brushless Yaskawa servo motors and drivesLarge Milling Machine CNC Control system: $25,760M400 3 axis with 4.4Kw AC Brushless Yaskawa servo motors and drives

Small Slant Bed Lathe CNC control system: $15,450T400 2 axis with 1Kw AC Brushless Yaskawa servo motors and drivesMedium Slant Bed Lathe CNC control system: $18,795T400 2 axis with 2.2Kw, 2.2kw w/brake AC Brushless Yaskawa servo motors and drivesLarge Slant Bed or VTL CNC control system: $21,597T400 2 axis with 4.4Kw, 4.4 Kw w brake AC Brushless Yaskawa servo motors and drives

Auto part set, Auto tool set, 3D contouring, 4th and 5th axis machining, Available in OEM configurations, Professional Installation with Service & Training and DIY CNC kits for both new machines and retrofit upgrades.

From the May issue of Modern Machine Shop Magazine " A CNC retrofit provides improved reliability and functionality compared to an older machine’s original control, and this is helpful in a number of ways. For example, a more intuitive control interface can help speed setups and minimize the chance for programming and/or setup mistakes, which could possibly damage or scrap a high-value work piece. Similarly, shops are also more confident in quoting work for large, expensive parts knowing the new control won’t hiccup partway through an operation and cause the part to be damaged. Shops also are better-positioned to take in “hot” jobs that require fast turnaround due to the retrofitted machine’s improved"... click here to see the complete article in PDF.

CENTROID Boss series II retrofit customer testimonial"The quality and workmanship of the CENTROID equipment was outstanding and very professional. CENTROID was able to custom tailor the control to allow us to continue to use our rotary milling arrangement as before and even expanded our capability. The short story is that we ended up with a four axis CNC mill for less than half the cost of the three axis Haas. This includes the work that was done by our staff."

Maybe you already know exactly how 3+2 and simultaneous 5-axis work, as well as their strengths and weaknesses, but you’re still thinking, “my shop can’t do, or doesn’t need, 5-axis.” We get it. 5-axis machines have a stigma of being too complex or too expensive, with underlying issues in positional inaccuracies as well as labor and software training. Luckily, today’s 5-axis machines are much more refined than the machines that existed even 5-10 years ago.

When you compare your standard vertical machining center to a 5-axis machine, the numbers can appear daunting. That’s why it’s important to look at the big picture. If your vertical machine uses special software or parts to achieve five axes or even a 3+2 operation, you’ve already spent the money in add-ons and processing time without receiving any of the 5-axis machine benefits (e.g., 5-axis auto tuning, posture control, etc.*). Plus, the return your shop will see with 5-axis heavily outweighs the initial cost.

It’s much easier to bridge the gap between your system and 5-axis machines than you think. If you already possess Mastercam, GibbsCam, Autodesk, Espirit, HyperMill, NX, or another similar software, your 5-axis machine can directly translate the code dialect.

At Okuma, we provide a multitude of resources for you when you purchase a machine. This includes 5-axis onsite training, PCNC Master, and offsite training. Between our partners (including education partners such as York Tech), your distributor, and our team, we’ll have you settled and making the most of your machine in no time.

Actually, 5-axis no longer requires specially trained labor, it’s almost as easy as any other machine! Our 5-axis machine’s dynamic fixture offset eliminates the need to set the part on the exact center of rotation, giving any employee the opportunity to excel in a 5-axis setup. Our machines are as close as possible to the “done in one” mantra, which means there’s a massive reduction of processing time and potential for human error.

As with any machine, advancements are constantly happening. Our OSP 5-axis auto tuning performs tuning quickly and accurately and compensates up to 11 geometric errors, including volumetric accuracy. Adjustments can be made in just 10 minutes, and it does not require a high level of skill.

100 mm (3.9") High-Speed Tilting 2-Axis Rotary Table, with indexing up to 1000 deg/sec. Requires a Haas mill with 4th- and 5th-axis drives for true 4th- and 5th-axis operation. Requires software version M18.24B or later. Not available for stand-alone operation.

5C Collet Tilting 2-Axis Rotary. Requires Haas mill with 4th-and 5th-axis drives for true 4th- and 5th-axis operation. This unit has no collet closing capability as standard. Requires a Haas mill with software version 18.00 or later.

Dual-Spindle 5C Collet Tilting 2-Axis Rotary. Requires Haas mill with 4th-and 5th-axis drives for true 4th- and 5th-axis operation. This unit has no collet closing capability as standard. Requires a Haas mill with software version 18.00 or later.

Triple-Spindle 5C Collet Tilting 2-Axis Rotary. Requires Haas mill with 4th-and 5th-axis drives for true 4th- and 5th-axis operation. This unit has no collet closing capability as standard. Requires a Haas mill with software version 18.00 or later.

Quad-Spindle 5C Collet Tilting 2-Axis Rotary. Requires Haas mill with 4th-and 5th-axis drives for true 4th- and 5th-axis operation. This unit has no collet closing capability as standard. Requires a Haas mill with software version 18.00 or later.

160 mm (6.3") Tilting 2-Axis Rotary Table. Requires Haas mill with 4th-and 5th-axis drives for true 4th- and 5th-axis operation. Requires a Haas mill with software version 18.00 or later.

160 mm (6.3") Tilting 2-Axis Trunnion Rotary Table, with scale feedback on the A (tilting) axis. Requires Haas mill with 4th- and 5th-axis drives for true 4th- and 5th-axis operation. Scale feedback functional only on Haas mills with software version 18.xx or later. Scale feedback does not function with rotary control box. Requires a Haas mill with software version 18.00 or later.

160 mm (6.3") Dual-Spindle Tilting 2-Axis Trunnion Rotary Table, with scale feedback on the A (tilting) axis. Requires Haas mill with 4th- and 5th-axis drives for true 4th- and 5th-axis operation. Scale feedback functional only on Haas mills with software version 18.xx or later. Scale feedback does not function with rotary control box. Requires a Haas mill with software version 18.00 or later.

200 mm (7.9") Compact Tilting 2-Axis Trunnion Rotary Table, with scale feedback on the A (tilting) axis. Mounts along Y axis of VF- 3 and larger machines. Requires Haas mill with 4th- and 5th-axis drives for true 4th- and 5th-axis operation. Scale feedback functional only on Haas mills with software version 18.xx or later. Scale feedback does not function with rotary control box.

210 mm (8.3") Tilting 2-Axis Rotary Table. Requires Haas mill with 4th-and 5th-axis drives for true 4th- and 5th-axis operation. Requires a Haas mill with software version 18.00 or later.

210 mm (8.27") Tilting 2-Axis Trunnion Rotary Table, with scale feedback on the A (tilting) axis. Requires Haas mill with 4th- and 5th-axis drives for true 4th- and 5th-axis operation. Scale feedback functional only on Haas mills with software version 18.xx or later. Scale feedback does not function with rotary control box. Requires a Haas mill with software version 18.00 or later.

310 mm (12.2") Tilting 2-Axis Trunnion Rotary Table, with scale feedback on the A (tilting) axis. Requires Haas mill with 4th-and 5th-axis drives for true 4th- and 5th-axis operation. Scale feedback functional only on Haas mills with software version 18.xx or later. Scale feedback does not function with rotary control box. Requires a Haas mill with software version 18.00 or later.

4ListofFiguresFigure 1. Haas OM-2 (Haas) ........................................................................................................... 9Figure 2. Haas TRT 100 (Haas) .................................................................................................... 10Figure 3. Nikken 5AX-130FA (Nikken) ....................................................................................... 10Figure 4. Anti-Backlash Mechanism Patent Design (Mauro) ....................................................... 11Figure 5. Rotary Table Bearing Patent Design (Bullard) ............................................................. 11Figure 6. Rotary Table Apparatus Patent Design (Kato) .............................................................. 11Figure 7. Manufacturers in Japan use blue ink to machine precision ground gears (Mitzubishi) 12Figure 8. Cone drive manufactured by Cone Drive Solutions (Cone Drive)................................ 12Figure 9. Duplex worm gear drawing provided by Allytech (Allytech)....................................... 12Figure 10. Split gear (Machine Design) ........................................................................................ 12Figure 11. Manually adjusted worm drive .................................................................................... 13Figure 12. Spring loaded spur gears to reduce backlash (Machine Design) ................................. 13Figure 13. SGMJV AC Servo Motor (Yaskawa) .......................................................................... 14Figure 14. Cutting Torque Data .................................................................................................... 15Figure 15. Cutting Force Distribution........................................................................................... 15Figure 16. Velocity Profile for Both Axes (Yaskawa) ................................................................ 16Figure 17. Axis A Motor Performance and Operating Point ........................................................ 16Figure 18. Axis B Motor Performance and Operating Point ........................................................ 17Figure 19. NEMA 23 Stepper Motor ............................................................................................ 19Figure 20. Back to back bearing configuration ............................................................................. 20Figure 21. NSK angular contact bearings ..................................................................................... 20Figure 22. Geometry Configuration, Cantilever-Cantilever and Cantilever-Fixed ...................... 24Figure 23. Cantilever spring forcer ............................................................................................... 25Figure 24. Worm gear backlash reduction system ........................................................................ 25Figure 25. Method to reduce backlash in worm drive .................................................................. 25Figure 26. Tapered Roller Bearings .............................................................................................. 26Figure 27. Thrust bearing .............................................................................................................. 26Figure 28. Gen5 rotary table with motor placement ..................................................................... 26Figure 29. Completed prototype 1 ................................................................................................ 27Figure 30. Rotary Schematic......................................................................................................... 28Figure 31. Gear preload system .................................................................................................... 29Figure 32. Rendering of rotary exploded view ............................................................................. 29Figure 33. Housing Maching Set Up ............................................................................................ 34Figure 34. Housing inspection ...................................................................................................... 34Figure 35. Spindle Machining....................................................................................................... 35Figure 36. Spindle Assembly ........................................................................................................ 36Figure 37. Perpendicularity Measurement .................................................................................... 37Figure 38. Custom stepper motor controller ................................................................................. 38Figure 39. Laboratory setup diagram ............................................................................................ 40Figure 40. Accelerometer mounting configuration on housing with components removed......... 40Figure 41. Housing mounted to the shake table ............................................................................ 40

6ListofTablesTable 1. Comparing Backlash Reduction Options (Machine Design) .......................................... 14Table 2. Axis B SigmaSelect Summary ........................................................................................ 17Table 3. Axis A SigmaSelect Summary ....................................................................................... 18Table 4. Yaskawa Motor Specs .................................................................................................... 19Table 5. Reduced specifications list used for concept generation ................................................ 21Table 6. Morphological matrix used to group solutions for concept generation .......................... 22Table 7. List of chosen concepts from the morphological matrix. ............................................... 22Table 8. Decision Matrix evaluating each concept according to important criteria ..................... 23Table 9. Decision Matrix for Backlash Reduction Methods......................................................... 24Table 10. Factors of Safety for Components ................................................................................ 31Table 11. Complete list of parts and cost for both rotaries ........................................................... 32Table 13. Stackup Chain ............................................................................................................... 33

7Executive SummaryDr. Jose Macedo and Professor Martin Koch of the IME department saw that there was noavailable 5th axis rotaries compatable with smaller CNC machines, and desired one in ordermachine more complex wax patterns for lost wax casting. Commercial 5th axis rotaries typicallycost around 30,000 USD, which is quite an investment for smaller institutions and so oursponsors Koch tasked our team with designing, building, and testing a 5th axis rotary table thatwill match commercial specifications at much lower, aproachable price point. The project beganby researching existing rotaries and developing a list of technical specifications that the designmust satisfy. Using these criteria, a preliminary design was created and initial calculations wereperformed to verify the design. The first prototype was manufactured and after performing a fewtests, changes for improving our next generation design was determined. The design wentthrough a complete overhaul, and a new prototype that was more robust and better designed formanufacturing was machined using CNC machines. Based of testing results, each rotary stagehas a natural frequency of about 400 Hz, which should be avoided when used for machining. A4th axis rotary table using a Haas specific Yaskawa motor was made as well as a complete 5thaxis rotary table. Over the course of the last quarter, the choice of motor changed due to sponsor-related circumstances, and so the resulting 5th axis design was chosen to be driven by two steppermotor and an external controller that works in conjunction with a G-code macro.

81. Introduction1.1 Sponsor BackgroundThe sponsor of this project is Dr. Jose Macedo and Professor MartinKoch of the IME department. Professor Koch often machines waxfor lost wax casting instead of molding the patterns, since the designsare typically unique. He and Dr. Macedo wanted to explore thepossibility of designing and building a 5th axis to machine complexpatterns, but it must fit in his existing Haas Office Mill.

1.2 Formal Project DefinitionThe IME department would like to have five axis simultaneous Figure 1. Haas OM-2 (Haas)machining capabilities to manufacture small wax parts. There aretwo Haas OM-2 vertical machining centers, which are currently available for this project. Due totheir small size, there are no commercial quality 4th and 5th axis rotary tables available in themarket. This team was created in order to design and build a low cost 4th and 5th axis rotarytable for the OM-2.

1.3 ObjectivesCompletion of this project entails the development of a 5th axis rotary table with compatiblefixture connections, appropriate drive cards, and 5th axis CAM software and postprocessor. Thetable must be able to rotate in two axes, while allowing the largest work piece possible. It mustmount to standard T-Slots, and have a platter with a standard bolt pattern sothat commercial fixtures may be attached. Structurally, we are aiming to resist light cuttingforces in wax or plastic under high-speed conditions. Our goal is to match the resolution,accuracy, and repeatability of existing large rotaries in the 25,000 USD price range. This goal isstated with the understanding that commercial systems reach their specifications by havingextremely tight component tolerances, which are typically produced with dedicated machines,and may not be entirely achievable.

1.4 Project ManagementFor this project, while everyone had a part in every step of the process, individuals were assignedto manage certain aspects of the project in order to assure that the project would be completed ontime. The design of the rotary was completed with every team member present. Ricky led theanalysis of crucial components and Nicole was in charge of the mechatronics side of the rotary interms of build and design. Irene managed the scheduling and the timeline to ensure that the teamwas on track for completion. Irene was also the main communicator with the sponsor. When timecame for manufacturing, Dakota lead the manufacturing due to his background with CNCmachines. The vibrations tests were conducted under Ricky and the Mechatronics tests wereconducted under Nicole.

92. Background2.1 HistoryOver the past two decades, the machine tool industry has been experiencing a shift towardlighter, smaller CNC machine tools (Arnold). Advancements in spindle tapers and grindingaccuracy have allowed small taper machines to compete with large machines. Popular smalltaper standards include HSK, BT-30, and BT-30 Dual Contact spindles (All Industrial). Thisshift towards smaller machines has been caused by the ability of such tapers to takehigher cutting forces than before. Also, high speed machining allows for the material removalrate (MRR) of these tools to match the MRR of larger machines (Albert).

The trend towards smaller CNC machines in industry has lowered the cost of small table size /small taper vertical machining centers to approximately 50,000 USD (Haas). At the same time,advances in CAM software have made programming parts simpler than ever before. Moreconsumer groups, such as high schools, light industry, universities, and dental practices arecapitalizing on the availability of these CNC machine tools.

2.2 Existing ProductsA concurrent trend in industry has been the utilization of 5th axis rotaries. Aftermarket 5th axisrotary tables can be bought for around 30,000 USD and add two additional axes to the threeexisting axes of a CNC machine. This allows parts to be machined more accurately in fewersetups while enabling the manufacturing of more complex parts. In many situations, purchasing a5th axis table can be a profitable business decision (Sherman). However, commercial quality 5thaxis rotary tables are not as available for the smaller machine market. Typical manufacturers of

Figure 2. Haas TRT 100 Figure 3. Nikken 5AX-130FA (Haas) (Nikken)5th axis tables include Lyndex-Nikken, Haas Automation, Tsudakoma, and Matsumoto. Their5th axis tables are not designed for machines with small table sizes, such as the Haas OM-2.Rotaries within the budget of small organizations are oversized and too heavy for smaller CNCmachines. There is a desire for small 5th axis rotary tables for small table sizes and low cuttingforces, which could bridge the gap between hobbyist tables and industrial tables. In the Cal PolyIME 141 lab, Haas OM-2 CNC machines are utilized to make wax shapes for sand casting. Forwax and soft plastic machining, there is a niche for accurate, but small 5th axis rotaries.

Bullards rotary patent uses an external oil port to keep the rotating contact points submerged at all times. This decreases the effects of wear on the rotary over time and minimized maintenance.

The Rotary Table Apparatus is essentially a fourth and fifth axis rotary table. This design focuses on small and light-weight properties.

Anti-Backlash Split GearsAnti-backlash split gears are commercially available gearsystems that are designed for light loads. They eliminatebacklash through a spring loaded second gear that takes upthe slop in the gear train. These gears are more expensivethan standard gears, and are an effective solution for lightloads. Figure 10. Split gear (Machine Design) 12Manually Adjusted Gear MeshManually dialing in a worm drive is common practicefor manual rotary tables. The worm is adjusted via aset screw that brings the worm and gear into eachother. This allows radial locational adjustment tocounteract manufacturing errors. The Anti-BacklashMechanism for a Rotary Stage patent by GeorgeMauro depicts this design and is further described inthe Patent section of this report.

Table 1 shows the three main criteria for backlash reduction options. As with many components,there is a balance between cost and quality that must be analyzed. Each method is suited fordifferent types of applications and used in certain types of systems. In addition, each solution hasdiffering amounts of backlash reduction.

2.4.2 MotorsEach axis must be controlled independently,which requires two motors and a controller.From collaboration with Haas Automation andYaskawa, we were initially advised to chooseamong the Yaskawa SGMJV motor series to becompatible with the Haas controller.Unfortunately, months later, we found out thatthe SGMJV motors are not compatible with the Figure 13. SGMJV AC Servo Motor (Yaskawa)Haas controller. Instead, we were givenproprietary 200-watt motors. The rest of this section includes the design process of sizing aSGMJV motor, which were ultimately not used in this project, but useful in sizing theappropriate NEMA stepper motors and for further advancements on this project.

Assuming six standard deviations, the max cutting force is 80 Newtons. With a 100mm platterdiameter, the torque seen by the gear train is 4Nm for the B axis, and 8Nm for the A axis.

In addition to cutting forces, the table velocity profile must be specified in order to size a motor.The velocity profile below shows the table accelerating to 100 rpm in 0.5 seconds and switchingdirections after a one-hour interval. This is considered our worst-case scenario motor operation.

After determining the operating point, the SigmaSelect program offered by Yaskawa was used tosize the motors. SigmaSelect inputs are applied torque, inertia, speed, efficiency, gear ratio, andvelocity profile. Outputs include motor recommendations and sizing options. The followingtables are inputs and outputs for the SigmaSelect program.

16 Figure 18. Axis B Motor Performance and Operating PointMotor performance charts for axis A and B show the worst-case operating point withincontinuous operation rating. According to SigmaSelect results, the factor of safety in theintermittent range for Axis A is 3.18 and axis B is 3.19.To better summarize inputs and outputs, the tables below summarize results from SigmaSelect. Table 2. Axis B SigmaSelect Summary RotaryAxis,B Category Parameters Units Value ExternalForces CuttingForce N 80 AppliedTorque Nm 4 Geometry TableDiameter m 0.1 CalculatedInertia TotalInertiaatMotor kg*m2 3.45E06 KineticProfile Acceleration sec 0.5 TopSpeed rpm 100 Deceleration sec 0.5 RunTime min 120 Gearing GearEfficiency 0.5 GearReduction 30 Power MinimumPower W 83.8 SigmaSelectResults RequiredTorque Nm 0.272 RequiredSpeed rpm 3000 RequiredPower W 85.5

A SigmaSelect simulation was performed for each axis operating point since inertia and torquevalues are different. Axis A, the tilt axis, requires twice the torque and significantly more inertia. 17 Table 3. Axis A SigmaSelect Summary TiltAxis,A Category Parameters Units Value ExternalForces CuttingForce N 80 AppliedTorque Nm 8 Geometry PartHeight m 0.1 CalculatedInertia TotalInertiaatMotor kg*m2 1.04E04 KineticProfile Acceleration sec 0.5 TopSpeed rpm 100 RunTime min 120 Gearing GearEfficiency 0.5 GearReduction 30 Power MinimumPower W 167.6 SigmaSelectResults RequiredTorque Nm 0.541 RequiredSpeed rpm 3000 RequiredPower W 170.0

It is also important to consider inertial effects on the motor accuracy. As the load inertiaincreases, the motor has more trouble keeping accuracy when positioning. Each motor is ratedfor an acceptable inertia, as shown in the Yaskawa Motor Specs table. Though our predictedinertias are below allowable, it is important to will test for inaccuracies with the closed loopsystem before finalizing the rotary.

18 Table 4. Yaskawa Motor Specs Motors SGMJV01A3A6S SGMJV02A3A6S Torque(Nm) Rated 0.2544 0.5096 Peak 0.888 1.784 Speed(rpm) Rated 3000 3000 Max 6000 6000 Inertia(x104kg*m2) Motor 0.0665 0.259 Allowable 1.33 3.885 BodyDim(mm,kg) Length 82.5 80 Width 40 60 Height 40 60 Weight 0.4 0.9 ShaftDim.(mm) Diameter 8 8 Length 25 25 Electronics Power(W) 100 200 Voltage(V) 200 200 Encoder 20BitAbsolute 20BitAbsolute

Fortunately, we can use our simulation data to source a stepper motor with the appropriate amount of torque. Although stepper motors run much slower than AC servo motors, as long as the torque is sufficient, the rotary will still function. Also, it is important to consider that stepper motors do not have built-inFigure 19. NEMA 23 Stepper Motor encoders, and will not be as accurate as closed-loop systems.

2.4.3 BearingsBearings are critical for our design in terms of minimizing run-out and providing the precisionwe need for our rotary table. Because of this, our rotary table requires bearings specificallydesigned for machine tools. General practice in the machine tool industry is to use two back-to-back angular contact thrust ball bearings.

19 Figure 20. Back to back bearing configurationThe preload between angular contact bearings is achieved by clamping a pair of bearingstogether. Preload increases rigidity, but consequently, it reduces rated speed. Preload alsoeliminates radial and axial play, increases accuracy and helps to prevent ball skid at high-speed.For our application, at a speed of 100 rpm, a large preload is best. For our spindle the NSK7006C Series bearings are applicable for our rotary table. They are also easily accessible forordering.Assembly using NSK bearings require narrow tolerances for fit, and so to dimension the shaftand housing placement of the bearings, we referred to the manufacturers recommendations. Thespecifications for these bearings are located in Appendix D.

3. Design Development3.1 Requirements/SpecificationsAfter meeting with our sponsors, we determined a list of customer requirements.The 5th axis rotary table should:

Work with small Haas CNC machines on light duty machining of wax-type materials at normal production cutting speeds Be capable of meeting or exceeding the speeds and accuracies of commercial 5th axis rotaries in the ~$25,000 price range Include a way to home the 5th axis mechanism Be safe for human operators Incorporate appropriately sized servomotors from Yaskawa

20In addition to the customer requirements, we created a specifications list to incorporateengineering specifications from which we used to start design process. A reduced list ofspecifications used for considering preliminary designs is shown below in Table 5. The fullspecifications list can be seen in Appendix A. The specifications were developed from evaluatingconstraints of the OM2, comparing specifications from existing products, measured loads, andoperating conditions.

Table 5. Reduced specifications list used for concept generation Engineering Number Feature Value Unit Source Compliance Risk 1. Geometry 1.3 Max Work Table Height 4 in OM2 Specs Inspection Medium 1.4 Max Rotary Height 10 in OM2 Specs Inspection Low 1.5B Work Area Diameter 3 in Rotary Comparison Inspection Low 1.6B Max Work Piece Height 3 in Rotary Comparison Inspection Low 2. Kinematics 2.1 Rotational Speed 30 rpm Rotary Comparison Test High 2.2 Tilt Speed 30 rpm Rotary Comparison Test High 3. Forces 3.1 Max Part Weight 5 lbf Rotary Comparison Test Low 3.2A Average Applied Load 18 lbf Spindle Loads Analysis Medium 3.3 Axis A (Tilt) 6 ft-lb Hand Calculation Analysis Medium 3.4 Axis B (Rotary) 3 ft-lb Hand Calculation Analysis Medium 4. Energy AC Motors OM2 4.1 - - Compatible with Haas Test Low Compatible 5. Materials 5.3 Wax machining - - Sponsor Requirement Test Medium 10. Assembly 10.1 Instructions - - Sponsor Requirement Inspection Low 10.2 Compatible with T-slots - - Sponsor Requirement Inspection Low 12. Usage / Operation 12.1 Workholder Bolt Pattern - - Rotary Comparison Inspection Low Sponsor 12.3 Simultaneous machining 5 axes Demand Test Requirement

3.2 Concept GenerationTo begin the ideation process we created a morphological matrix in which solutions weregenerated for each sub-function of our design. These sub functions or sub-components includedthe type of transmission for the 4th and 5th axes, how the work piece was to be mounted, howthe rotary was to be mounted on the table, the bearings used, and the geometry between the 4thand 5th axes.

21 Table 6. Morphological matrix used to group solutions for concept generation Subfunction Solution Work Part Hole Collet Collet Mounting Pattern (Hand tight) (Automatic) 4th Axis Belt Worm Bevel Spur Planetary Direct Drive Transmission 5th Axis Belt Worm Bevel Spur Transmission Bolt Table Mounting Clamps Pattern Bearings Ball Tapered Roller Journal Thrust Needle 4th & 5th axis Inline Swing Arm Trunnion connection

From the morphological matrix, solutions were combined to create hundreds of completeconcepts. In order to produce a more selective list of concepts to choose from, we eliminatedsome solutions from each sub-function if the solution was not feasible, or other solutions seemedto be much better options in terms of performance, manufacturability, and availability. Theoptions in blue are the solutions we decided to use as concepts. We decided not to includebearings in the detailed drawings because the type will be determined by the rest of the design aswell as space constraints. Since a hole pattern and bolt pattern were our only options, theconcepts focused on the decision of the transmission for the 4th and 5th axes and the structurebetween them. From these concepts we chose 11 to draw out in detail, which are listed in Table 7and attached in Appendix B. Two of the chosen concepts were wild card drawings to explorethe pros and cons of concepts that satisfy the criteria but have an unexpected design. Eachdrawing was discussed in terms of how well the design would suit the goal of the project. Weevaluated all of the sketches in terms of the criteria in the table below and rated each sketch avalue of 1 to 4 where a 1 was given if the design was least desirable in fulfilling the criteria and 4was the most.

Table 7. List of chosen concepts from the morphological matrix. Solution 4th Axis 5th Axis Connection 1 Planetary - Belt Trunnion 2 Belt Belt Inline 3 Direct Drive - Worm Swing Arm 4 DABS Swing Arm 5 DASS Trunnion 6 Spur - Worm Inline 7 Worm - Belt Trunnion 8 Worm - Worm Trunnion 9 Worm - Worm Inline 10 Worm - Worm Swing Arm 11 Belt - Worm Swing Arm

22 Table 8. Decision Matrix evaluating each concept according to important criteria Solution # Criteria 1 2 3 4 5 6 7 8 9 10 11 Minimal Workpiece Height 1 1 4 2 4 3 1 4 3 4 4 Minimal Backlash 1 4 3 4 3 2 3 3 3 3 3 High Rigidity 3 1 3 2 3 2 3 4 3 3 2 Minimal Weight 1 4 1 1 2 3 2 2 4 4 4 High Efficiency 2 4 2 4 2 1 2 1 1 1 2 High Manufacturability 3 3 4 1 2 3 3 2 3 3 3

3.3 Initial Design Considerations3.3.1 Support DesignThe design of a modern rotary table is a complex task, typically limited to large corporationswith decades of experience in the matter. We will design a single rotary stage that could bemanufactured twice and joined to yield a full 5th axis table. The primary engineering features thatpreceded our design and how they apply to the design of our first prototype follows.

StructureThe structure of the machine tool is of primary importance. We do not expect our table to yield,but our design is stiffness limited, with cutting forces causing deflection and making loss ofaccuracy our primary concern. It is also important to stay above the natural frequency of ourapplied loads by ensuring the structure is stiff enough, and counteract any harmonics with adamped design.

Two materials most suitable for this application are cast iron and epoxy-granite composite. Castiron has a yearlong settling time after casting, and as such is unacceptable for our timeline.Epoxy granite is a composite material consisting of granite and quartz particles in an epoxymatrix, and has one of the highest damping factors for any material. Its downside is its lowstrength, which we have considered improving by coming up with a new epoxy-granite-fibermatrix wherein we add carbon or glass chopped fibers to the mix to improve stiffness andstrength. This will be investigated in the future, due to the large R&D required to manufacturesuch a material. We are designing around 6061-T6 AL due to availability and comparablestiffness to epoxy granite.

23 The geometry of our housing was determined to be double-cantilever as shown in Figure 22. This is beneficial because it allows us to design one rotary for both the A and B axes. The major elements of the housing are that it must hold tapered roller bearings, a preload mechanism, a worm drive, and a circular bore for a platter. It is a uni-body design, with the entire structure to be machined out of aluminum.

AntiBacklashDesign We evaluated anti-backlash methods on a numerical basis, where a score of 1 is the lowest score and 4 is the highest score. Table 9 shows our decision matrix results. Table 9. Decision Matrix for Backlash Reduction Methods

Figure 25. Method to reduce backlash in worm drive 25BearingsThe bearings in our design are critical given the high loads that we expect to experience. Thisproblem is further complicated by the fact that cost is a major issue. We designed ourpreliminary rotary housing to use Timken tapered roller bearings. These SET45 Timken bearingsare readily available at auto parts stores, and the runout on several can be inspected beforepurchase, allowing us to use low runout bearing through the laws of averages.

Prototype1DesignThe end result of this is a rotary platform that is both low cost and highly accurate. For the PDRwe purchased a NEMA 23 stepper and motor controller to evaluate the geartrain efficiency andrun tests before comitting to a servo from Yaskawa. This is because friction factors are hard topredict, and empirical data is always more accurate. After we complete a functioning prototype,we will be able to iterate our design and properly pick a motor. Figure 28 shows images of ourrotary table design.

We manufactured a single rotary as described above and have completed testing on it. Bothduring the manufacturing process and during testing we determined some design changes that

26would need to be made for this rotary to be completely functional. We had noticed that aftermanipulating the rotary that the worm wheel was not meshing with the worm gear. The shoulderbolt used for shaft was not rigid enough to maintain straightness and runout. Many of thedimensions and fits needed to be reconsidered for assembly as well. The cavity for the gear wasinaccessable for assembly and the gear itself appeared to be too small to move the rotary. Weused this knowledge to create a design for our second prototype, which we will be described onthe following section.

27 Figure 30. Rotary Schematic4.2.1 CapThe cap holds the outer race of bearing in place and provides the preload in conjunction with thebearing locknut. It also has grooves for O-rings to prevent contaminants from entering the rotary.Half of the reed switch used for homing is contained in the cap. The cap was manufactured usinga Haas CNC Mill.

4.2.2 HousingThe housing is to be manufactured from aluminum. It was redesigned to accommodate our newinternal configuration. There are different configurations for the B axis and the A axis. Thefeatures on both stages are nearly identical with the only difference being that the A axis hasmore material on the bottom of the stage to lift the B axis higher to prevent it from crashing intothe table. The housing was manufactured using a Haas CNC Mill.

4.2.3 PlatterThe updated design consists of a detachable platter that is bolted to the shaft. The platter has thesame hole pattern as the TRT-100. It will be made out of steel, with a reed switch located on theside for homing. The platter also has a bore in order to accommodate fixtures. The platter wasmachined on a Haas CNC lathe.

4.2.4 ShaftThe shaft is precision manufactured of a Haas CNC lathe to accommodate the tight tolerancesrequired to shrink fit the NSK bearings. Below the bearings the shaft is threaded for a bearing

28locknut to provide preload to the bearings. Lastly, a conical section locates and fastens the gearto the shaft. The shaft will also be manufactured on a Haas CNC lathe.

4.2.6 Worm WheelThe worm wheel is an off-the-shelf part that was modified for our rotary. A conical countersinkis machined into the worm wheel to perfectly contact the spindle and for proper concentricalignment. This design allows the operator to easily replace the worm wheel for another whenworn out.

4.3.3 InertiaEach Yaskawa AC servo motor is specified with an allowable inertia value that will allow foracceptable motor response. If inertia values exceed those specified by the manufacturer, themotor will not be accurate in positioning the rotary. This code calculates the inertia due to theplatter, motor, housing, drive shaft, worm gear, and coupling as seen by each axis motorseparately. Inertia values for each axis is relatively low due to the 30:1 reflected inertia ratio andgive a factor of safety of 3.73 against response error.

4.3.4 Worm Gear A and BThis code evaluates the worm gear for 25000 hours of life using the AGMA method. It isassumed that the worm will outlast the gear by a large margin due to material properties. In aneffort to share parts between the rotaries, each axis will use a 16 diametral pitch worm and gear.As these gears are critical to the function of our design, the factor of safety against fatigue failureover 25000 hours is 2.80 and 5.04 for axes A and B respectively.

4.3.5 BearingsIt is important that our bearings are rated to the expected loads on the rotary. The most criticalparameter is the spacing between the bearings and their ability hold an applied moment. To savespace in the rotary, two NSK precision bearings are preloaded without a spacer. Without aspacer, the bearings are still capable of the expected loads with a minimum factor of safety of6.6.

4.3.6 BoltsThe code analyzes the bolts that attaches axis B to axis A. There are two sets of bolts to evaluate:the bolts that attach axis B to the fixture plate, and the bolts that attach the fixture plate and axisB to axis A. The largest stress the bolts will see is shear stress. -20 Grade 1 Bolts were usedfor the analysis, resulting in a safety factor of 90.63 for the bolts that attach to axis B and a safety 30factor of 45.32 for the bolts that attach to axis A. The minimum length of engagement for thethreads of the bolts is 0.2856 inches.

Table 10. Factors of Safety for Components Part Longevity FactorofSafety Reference AxisBGear 25000hrs 5.04 AGMAMethod AxisAGear 25000hrs 2.80 AGMAMethod DriveShaft EnduranceLimit 2.98 MarinFactors DrivenShaft EnduranceLimit 20.67 MarinFactors AxisABoltFixture StaticLoading 45.32 Shear AxisBBoltFixture StaticLoading 90.63 Shear AxisBBearings StaticLoading 15.4 BearingLoadRating AxisBBearings StaticLoading 85.56 AxialRating AxisABearings StaticLoading 6.6 BearingLoadRating AxisABearings StaticLoading 40.53 AxialRating

4.4 Cost AnalysisWe have analyzed the cost of both rotaries in a worst case scenario, as shown in the table below.The cost of the 5th axis that we are building for our sponsor will be much lower, as we are gettingthe motors donated from Yaskawa and the bearings at a lower price on eBay. If this were to bemanufactured by someone else, they could research other sources to buy quality parts at areduced cost. If this were to be mass produced, costs would also be reduced by purchasing inmass quantities.

31 Table 11. Complete list of parts and cost for both rotaries CostAnalysis Part/Material Qty Supplier Supplier# Cost Steel 1 IMEDept N/A Aluminum 1 McMaster 290.00 0.25"x0.5"DowelPins 6 McMaster 97395A475 10.21 3/16"x1.25"DowelPins 4 McMaster 97395474 11.25 BallNoseSpringPlunger 2 McMaster 3408A75 7.24 1032x0.5"SocketHeadCapScrews 13 McMaster 92185A989 4.26 1032x0.75"SocketHeadCapScrews 24 McMaster 96006A693 5.71 GasketMaterialNeoprene 2 McMaster 8837K112 21.70 75mmx3mmwideOring 4 McMaster 9262K409 6.26 19/16"BearingLockNut 2 McMaster 6343K160 14.44 3mmSetScrew 2 McMaster 92015A101 9.34 1/4"Shaft 2 McMaster 1144K11 24.15 1/4"IDWasher 2 McMaster 98019A360 6.75 3/4"x.75CapScrew 2 McMaster 90201A111 9.62 SmallBallBearing 2 McMaster 57155K388 9.56 14mmBallbearing 2 McMaster 2423K24 38.22 1/4"20SocketHeadbolts 8 McMaster 90128A242 9.09 1/4"8mmShaftCoupling 1 McMaster 2764K123 60.54 1/4"14mmShaftCoupling 1 McMaster 2764K322 78.69 7006CNSKBearings 4 McMaster 2385K46 1,091.00 SPDT150VDCReedSwitch 2 McMaster 6585K22 92.22 30T16DPGear 2 BostonGear G1043 91.60 16DPWorm 2 BostonGear LVHB1 46.40 200WMotor+Cable 1 Yaskawa SGMJV02A 550.00 100WMotor+Cable 1 Yaskawa SGMJV01A 500.00

5. Product Realization5.1 ManufacturingThe nature of the rotary table requires a very high level of precision, typically beyond the levelswe would be able to achieve in a school setting without precision scraping. This is due to the factthat our system design features a long tolerance chain from the machine table to the rotating Baxis. This chain, as it were, is composed of a number of different machined or groundcomponents which must be maintained within very tight tolerances because their affect onsystem accuracy is compounded greatly throughout the project.

System Tolerance Stackup ChainTolerance Feature Moment Arm Material ToleranceHousing A Perpendicularity of bottom 175mm 6061AL 2 micronssurface to bearing boreBearing set A outer race to inner race 27.5mm Tool Steel 2.5 micronsparallelismSpindle A perpendicularity of datum 10mm Steel 5 micronssurface to center axisPlatter A parallelism from top to bottom 12.6mm Steel 2.5 micronsplaneAdaptor plate perpendicularity from A to B 100mm 6061AL 20 micronsmounting planeHousing B Perpendicularity of bottom 100mm 6061AL 2 micronssurface to bearing boreBearing set B outer race to inner race 27.5mm Tool Steel 2.5 micronsparallelismSpindle B perpendicularity of datum 10mm Steel 5 micronssurface to center axisPlatter B parallelism from top to bottom 12.6mm Steel 2.5 micronsplaneSummation 44 microns

The above table illustrates the fact that even with incredible precision beyond 99 percent of mostmachine shops in the world, the total tolerance stackup is over 44 microns, which frankly isunacceptable for a rotary table. In order to remedy this situation, we used unique machiningtechniques to achieve high levels of precision in only our critical dimensions, and individuallymatched parts to hit our tolerances. This was time consuming and took hundreds of hours.

5.2 Design EditsOur planned design described previously in this report was to use Yaskawa servomotors inconjunction with the 4th and 5th axis drive cards from Haas, both of which were donated for ourproject. In order for the motor to interface with the 4th and 5th axis driver cards, we were sent theexact servo motors that Haas uses on their rotaries. Because of this, the motors were much largerand heavier than what we had been planned for and so they could not be used with our design.This was determined very late in our project, so our sponsor requested that we manufacture just afourth axis that is compatible with Yaskawas donated motor.

In order to complete the project that our sponsors originally asked for, we decided to create acomplete 5th axis that was run with stepper motors and an external controller. A G-code macrowas written that calculates the position of each axis and outputs them through the serial line astext. This text line is sent to the microprocessor of our controller, an Arduino Uno, which parsesthe string into recognizable commands and variables. If the letter H is sent, each axis is homed,by spinning until the reed switch registers and then moving to a predetermined offset. Otherwise,each axis can be sent a direction and number of degrees and the Arduino will calculate howmany steps to turn the stepper to move to the new angle.

37Pictured below is the controller, which contains two AC to DC power supplies, a 24 Volt one forthe motors, and a 12V one to power the Arduino. Pololu DRV8825 stepper drivers are used tosend commands to the steppers. A MAX3223 breakout from Sparkfun is used to convert theRS232 input to TTL so that the Arduino can properly receive the text. We chose to use NEMA23 stepper motors with 179 oz. in. of torque in order to withstand machining loads and maneuverthe weight of the B-axis.

5.3 Recommendations for Future ManufacturingWhile we have gone through three prototypes during our senior project in order to refine thedesign and improve manufacturing, there are still a few changes to make in terms of machiningthese parts. Dimensions that have fits should be machined to nominal sizing, and then reamed forfit. Most features should be designed for a slip fit rather than an interference fit if the mating isnot crucial, as it will eliminate the need to risk the part during pressing. If the feature is crucial,machine undersize, and check the dimension before re-machining to size. The accuracy of ourCNC machines were not up to par for machining tolerances of fixtures and so the dimensions hadto be manually accounted for by the operator. Dimensions should be checked after machiningeach part and before assembly. Also, it is crucial to consider flatness tolerances on the platter ofthe rotary, and so the spindle and the platter should be surface ground before assembly.

6.2 Vibration TestingBackgroundVibration testing uses a sine sweep to find the natural frequency of the rotary. Operating at thenatural frequency of the rotary can cause inaccuracies in machining, and possible structuralfailure.

Equipment Rotary Accelerometer Signal Analyzer Blue Box Charge Amplifier Shake TableProcedure 1. Secure the rotary table to the shake table and attach the accelerometer with a dab of wax, as seen in the set-up figure. 2. Connect the charge amplifier to the accelerometer and channel two of the signal analyzer. 3. Preset the signal analyzer to sine sweep between 10-2000 Hz, where the input is channel one and output is channel two. Display the Bode Diagram with a linear magnitude. 4. Connect the signal analyzer source to channel one and the input for the shake table controller via a tee junction. 5. Turn on the hydraulic pump and follow directions posted on the shake table control panel. 6. Press start on the signal analyzer to start the sine sweep and record data. 7. Trace results to find each mode of natural frequency and print the bode diagram. 8. Repeat the procedure at least three times with the housing assembled and disassembled.

Figure 40. Accelerometer mounting configuration onhousing with components removed Figure 41. Housing mounted to the shake table

Procedure 1. Place Housing on a micro-flat granite table. 2. Attach dial indicator to magnetic base and lower the dial indicator onto part until the tip is depressed. 3. Run dial indicator across the part and measure the height at 5 points along the surface. 4. Find the range of points across the surface. The value is the flatness tolerance of the part. 5. Using datums noted on drawings at MMC, see if dimensions are within tolerance.

7. Conclusions and RecommendationsWe have created a robust design to meet the specifications of our sponsors. Our factors of safetyensure a safe mechanism to last our rated 2400 working hours. The majority of our parts are offthe shelf from McMaster Carr, and assembly can performed in any basic shop. There are 7 partsto be manufactured in house for each rotary. This allows our product to be created by otherschools or home machinists with access to a mill, lathe, and laser cutter. We are confident in ourdesign and in the ability to manufacture and test it.

In terms of improvements that could be made, the rotary could be better designed for assembly.Press fits should be minimized and slip fits should be chosen instead. The preload applied to thebearings were difficult to determine and so a better method needs to be devised in order toprovide the appropriate preload. The design could also be more modular, so that subassembliescould be