July 2010 - Symbiotic Supply Chain Design Strategies
Pro Tips eNewsletter- July 2010 --Design tips to reduce machining costs-- See the online version Here Pro Tips - July 2010 Symbiotic Supply Chain Design Strategies Last month's newsletter discussed optimal corner radii. This month we have a guest writer who will cover a broad overview of DFMA (Design For Manufacturability & Assembly) from a strategic supply chain perspective. Jon Edwards works in the sales department here at Pro CNC. This is a summary for a white paper which can be found on our website here. This past spring, I wrote a whitepaper as course work for an English class.…...
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June 2010 - Optimal Corner Radii
Pro Tips eNewsletter- June 2010 --Design tips to reduce machining costs-- Pro Tips - June 2010 Optimal Corner Radii Last month's newsletter discussed some ideas for making drawings simple for machining. This month we are going to revisit the topic of inside corner radii and talk about a new detail not previously discussed. This topic was suggested by Larry V. at Lockheed Martin - thank you Larry! For many parts, the length of time it takes to machine the part is the single largest cost (more than material, plating, set-up costs). For parts like these, optimizing the cutting time is…...
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May 2010 - Making Simple Drawings
Pro Tips eNewsletter- May 2010 --Design tips to reduce machining costs-- Pro Tips - May 2010 Making Simple Drawings Last month's newsletter was an of overview of CNC machines and how they work. This month we are going to look at ways to simplify your drawings with the express purpose of reducing the cost of manufacturing and inspection. I am going to make an assumption for the sake of this newsletter that the machine shop making your parts is using 3D model-based programming and does not require a fully dimensioned drawing in order to do the programming. If that isn't…...
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April 2010 - Overview of Turning Centers
Pro Tips eNewsletter- April 2010 --Design tips to reduce machining costs-- Pro Tips - April 2010 Overview of CNC Machines and the Parts they Make (part 2) Last month's newsletter was an overview of the differences between vertical and horizontal CNC mills. This month we are continuing the topic but discussing turning centers, and mill/turn machines. If you are designing parts that are round, or more-or-less round, there is a good chance that a turning center is the most suitable machine to make it on. The simplest type of turning center (Figure A) can only make parts that are entirely…...
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March 2010 - Overview of CNC Machines (part 1)
Pro Tips eNewsletter- March 2010 --Design tips to reduce machining costs-- Pro Tips - March 2010 Overview of CNC Machines and the Parts they Make (part 1) Last month's newsletter was an overview of raw material sizes and what is available off the shelf to minimize costs. This month we are going to take a step way back and look at an overview of different types of CNC machines. This is such a vast topic that this month we will only cover some types of CNC mills. Bill Bedenbaugh from DRS in Maryland suggested that describing the different types of…...
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February 2010 - Raw Material Sizes
Pro Tips eNewsletter- February 2010 --Design tips to reduce machining costs Pro Tips - February 2010 Raw Material Sizes Last month's newsletter was a case study showing changes that were made to a real customer part to save them money. This month we are going to look at the available sizes and forms of raw material, and their related costs. I would like to say thank you to John Hunt from Lockheed Martin for the suggestion of this newsletter. John, I hope you like your Pro CNC baseball cap. Back in December 2008 we discussed how costs can be saved…...
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January 2010 - Case Study # 3
Pro Tips eNewsletter- January 2010 --Design tips to reduce machining costs-- See the online version Here Pro Tips - January 2010 Case Study # 3 Last month's newsletter was a case study showing changes that were made to a real customer part to save them money. This month we are going to look at a third case study, unfortunately one without a good ending. We were asked to quote on this part below. It was part of a large package of parts for a new program that would need thousands of parts over a few years. It was the kind…...
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December 2009 - Case Study #2
Pro Tips eNewsletter- December 2009 --Design tips to reduce machining costs-- See the online version Every month we feature a really cool part that we have made. December's Part of the Month is this gold plated Alto Saxophone Mouthpiece. This part is our own product sold under the Theo Wanne Classic Mouthpieces brand. Made from solid CNC machined brass on a 4 axis CNC mill, it has incredibly tight tolerances which turns out to be very important to achieve the best sound possible. It is then gold plated and assembled with a ligature and pressure plate. See more cool parts…...
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November 2009 - Case Study #1
Pro Tips - November 2009 Case Study #1 Last month's newsletter discussed threads and plating. This month we are going to start a series of case studies, where we look at a part as it was originally designed, and then look at the changes that we made to make it more cost effective to machine. We were asked to machine this part below in Figure A. It doesn't look that bad at first but there are lots of hidden details that were driving the cost up. The first and most obvious was its overall size. The part was designed as…...
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October 2009 - Threads and plating
Pro Tips - October 2009 Threads and Plating Before we get into this months newsletter, we are very pleased to announce our brand new web site which was recently launched. Please check it out here: www.procnc.com. With 90+ pages, more resources, and finally an image gallery worthy of the types of parts and assemblies we build, we hope you find it to be a good resource, bookmark it, and return often! Last month's newsletter discussed designing and machining plastic parts. This month (which marks the first anniversary of our newsletter !!!) we are going to discuss the combination of threads…...
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September 2009 - Designing and Machining Plastic Parts
Pro Tips - September 2009 Designing and Machining Plastic Parts Last month's newsletter discussed a situation where both our customer and Pro CNC missed some details on an ambiguous drawing, which was an expensive mistake. This month we are going to introduce the topic of designing and machining plastic parts. This is a vast topic so this month's newsletter will just be an overview which we will elaborate on in future newsletters. There are many applications where it makes sense to design a machined part to be made from plastic rather than metal. There are many types of plastic each…...
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August 2009 - Learning from Our Mistakes
Pro Tips - August 2009 Learning from Our Mistakes Last month's newsletter discussed countersinks and chamfers. This month we are going to discuss an unfortunate situation that was expensive and that could have been easily avoided. We hope that people can learn from our mistake. Please read this carefully to get the full effect of this situation. We got an order for a pretty simple part for a customer of ours. When we received the order, we received a PDF drawing of the part but not a 3D model. The drawing below in Figure A shows exactly how the drawing…...
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July 2009 - Countersinks and Chamfers
Pro Tips - July 2009 Countersinks and Chamfers Last month's newsletter discussed bilateral vs unilateral tolerances. This month we are going to cover a fairly simple topic - countersinks, chamfers and the tolerances of these types of features. Any machined part that has holes in it probably also has countersinks. Countersinks are used as a lead-in for threads, for flathead screws, and just as a general edge break or chamfer on any type of hole where a lead-in is necessary. In many cases, the diameter of a countersink is not very critical and can often be dimensioned at a lower…...
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June 2009 - Bilateral vs. Unilateral Tolerances
Pro Tips - June 2009 Bilateral vs. Unilateral Tolerances Last month's newsletter discussed Surface Profile tolerances. This month we are going to stay on the topic of dimensional tolerance but focus on unilateral vs. bilateral tolerances. Bilateral tolerancing (also known as symmetric tolerancing) is a method of tolerancing a dimension using equal plus and minus deviations from the nominal dimension. Unilateral tolerances (also known as asymmetric tolerances) on the other hand specify a deviation in only one direction, either plus or minus, from the specified nominal dimension. Unilateral tolerances may also take the form of plus and plus-plus, minus and…...
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May 2009 - Total Surface Profile
Pro Tips - May 2009 Pro Tips In Action! We had such a great response last month that we would like to continue our special offer again. Send us your most difficult, trouble-prone, or expensive part. We will offer a FREE 30 minute DFM (Design for Manufacturability) consultation with our best engineers and show you how to reduce the cost of your part by 10% minimum
.(JavaScript must be enabled to view this email address) and we'll show you how we put into practice what we preach. Total Surface Profile Last month's newsletter discussed undercuts. This month we are going to talk about surface profile…...
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April 2009 - Undercuts
Pro Tips - April 2009 Undercuts Last month's newsletter discussed chemical conversion coating and anodizing. This month we are going back to geometry to talk about undercuts in machined parts. Sometimes it is impossible to avoid creating a feature that can't be made with a standard endmill; often this means using an undercut feature. See Fig. A for an example. These features are generally more expensive because they require a custom ground tool (see Fig. B) in most cases and the cutting feeds are slower to accommodate the more fragile neck (N) diameter. Both the speed of the cutter and…...
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March 2009 - Anodizing and Chemical Conversion Coating
Pro Tips - March 2009 Anodizing and Chemical Conversion Coating Last month's newsletterdiscussed some cost drivers and details with threaded holes and threaded inserts. This month we are going to talk about two different types of plating and some strategies to make those finishes more successful and cost effective. Chemical Conversion Coating In reference to coating aluminum, this process is known by many common names - chem film, Iridite, Alodine, conversion coat or chromate. Chemical films are gelatinous films used to provide corrosion protection to aluminum alloys. The coating also improves adhesion of subsequent coatings such as paint and powdercoat.…...
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February 2009 - Threaded Holes Overview
Pro Tips - February 2009 Threaded Holes Overview Last month's newsletter discussed some of the factors related to tolerances that drive machined part cost. This month we are going to talk about threaded holes and threaded inserts. We will go into greater depth in future newsletters about other types of holes and threads. Threaded holes can vary widely in cost. One thing to keep in mind is that depths of threaded holes are harder to control and costs can increase quickly for threaded holes with tight depth tolerances. The reasons behind the high costs are very low first part yield…...
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January 2009 - Tolerances
Pro Tips - January 2009 Tolerances Last month's newsletter discussed some of the issues with specifying material sizes and specs. This month we are going to discuss the topic of geometric tolerances and how they drive cost. Nothing can drive up costs on a part more quickly than tight tolerances that are difficult to machine or measure. Some tight tolerances are not any problem at all to achieve, while others are very challenging. All too often we see drawings with poorly applied tolerances which drive up the cost of the part or worse, potentially not fitting together with its mating…...
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December 2008 - A Few things about Material
Pro Tips - December 2008 A Few Things About Material Last month's newsletter discussed some of the issues specifying floor and wall radii. This month we are going to leave the topic of geometry and instead talk about material specs, sizes, and other material cost drivers. The ideal scenario for selecting a material for your parts - is to choose one that is the cheapest and most readily available that has the material properties you need. But there are some pitfalls for a task as seemingly simple as this. The first is the form that the material comes in. Let's…...
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November 2008 - Wall vs. Floor Radii
Pro Tips - November 2008 Wall vs. Floor Radii... Last month's newsletter discussed the length to diameter ratio of inside corner radii. We are going to explore this general topic a little further in depth this month. It isn't uncommon for engineers to put a radius both on the floor and wall intersection as well as the vertical walls (see fig A). With the "apply round" or fillet feature on most 3D CAD systems, the easiest thing to do is to select both that floor intersection and the wall intersections and just apply the same size radius to all those.…...
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October 2008 - Reeling over Radii
Pro Tips - October 2008 Reeling over Radii... One of the single biggest cost drivers for machined parts is the length of time it takes to machine it. The rigidity and strength of the actual cutting tools often determines how much time it takes. Very simply, the shorter a tool is, the faster it can feed, and the less the part will cost to make. The selection of these cutting tools is determined by the design of the part and a few simple rules can really help reduce machining time. When designing parts that have pockets, or other features with…...
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