# Bar Stock Cost Estimating for Screw Machine and Swiss Parts > Source: https://netray.co/resources/bar-stock-cost-estimating-screw-machine-parts > Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems. > Section: Knowledge Base ## Short answer Estimate bar stock cost for screw machine and Swiss parts: bar length, remnant, cutoff kerf, face-off, mill minimums and yield per bar, with ERP tips. ## Category ai-automation ## Content **Intro:** Bar stock cost per part is the cost of one bar divided by the number of good parts you actually get from it, not the finished weight times the price per pound. Real yield per bar depends on part length, parting blade kerf, face-off stock, the remnant the bar feeder leaves behind, and scrap. On short stainless or brass parts, those losses can be a large share of material cost. This guide shows how to calculate yield per bar, handle mill minimums and heat lots, and keep the number consistent between the quote and the ERP. **Sections:** #### The Yield-Per-Bar Calculation **Body:** Start with usable bar length: the stocked length (commonly 10 or 12 feet, sometimes 144 inches or metric 3 meters) minus the remnant that cannot be fed. Remnant depends on the machine, the guide bushing and the bar feeder, and it is often several inches. Then divide usable length by the sum of finished part length, cutoff kerf and face-off stock per part. Round down, because you cannot make a fraction of a part. Finally, apply setup scrap (the first parts and any bar-end parts you cannot trust) and a process scrap rate. The result is good parts per bar, and bar cost divided by that number is true material cost per part. **Bullets:** - Usable length = bar length minus remnant - Length consumed per part = part length + kerf + face-off - Parts per bar = usable length divided by length consumed, rounded down - Cost per part = bar cost divided by good parts per bar #### Choosing the Bar Size and Tolerance **Body:** Price the bar you will actually load, not the finished diameter. A part with a 0.500 inch major diameter might run on 0.5625 inch cold-drawn bar, or on precision ground bar if the tolerance and finish demand it. Ground bar costs more per foot, but can eliminate a finishing pass or a centerless grind operation. Hex and square bar exist for parts with those features and save machining. Common screw machine materials include 12L14 and 1215 free-machining steels, 303 and 416 stainless, 360 brass and 6061 aluminum, while medical shops run 316L, 17-4 PH and titanium to ASTM F136. Each has a very different price volatility, so confirm the quote validity period. #### Mill Minimums, Heat Lots and Surcharges **Body:** Distributors and mills price bar differently by quantity. A 5 bar order, a full bundle and a mill run have different per-foot costs, and special requirements such as a certified 3.1 mill test report, a specific heat treat condition, domestic melt or a single heat lot for the whole job can add cost or lead time. Alloy and stainless pricing also carries surcharges that move with nickel and other metals, so a quote built on last quarter's price may be stale. A defensible quote states the price basis, the validity window and what happens if the material price moves materially before release. **Bullets:** - Record the quantity break assumed for each bar buy - Note single-heat-lot or domestic melt requirements on the quote line - Set a quote validity window tied to the alloy surcharge cycle - Add freight and cut-to-length charges where applicable #### Keeping Estimates and ERP in Agreement **Body:** Many shops estimate yield on a spreadsheet and then run the job in an ERP that treats material as a quantity per piece. The two drift apart, and the job closes with a material variance nobody can explain. Better ERP setups model the bar as the purchased item, with a conversion to parts per bar on the routing or BOM, and issue material in bar units or by weight with a yield factor. Whatever system you use, capture actual bars issued, remnants returned to stock and scrap per job, so the next estimate uses real yield instead of theory. JobBOSS, E2, ProShop, Global Shop, Epicor Kinetic and Infor SyteLine all handle this differently, and it is worth testing in a demo with your own part. #### Where AI Helps and When It Does Not **Body:** AI helps by mining past jobs: for a new part in 303 stainless at a similar diameter and length, it can pull the actual bars issued, parts produced and scrap from comparable jobs and suggest a yield, rather than relying on the theoretical number. It can also read the RFQ for material callouts and flag special requirements like a single heat lot. It will not replace the arithmetic, which is simple. If your shop runs mostly repeat parts with stable yield in the ERP, a spreadsheet or built-in calculator is enough, and AI adds little. **Cta:** Netray can compare your estimated bar yield with actual bars issued across past jobs in your ERP, privately and read-only, so your next quote starts from real numbers. **Faq:** #### How do you calculate parts per bar for screw machine work? **Answer:** Subtract the unusable remnant from the bar length, then divide by the part length plus parting kerf plus face-off stock, rounding down. Apply setup and process scrap to get good parts per bar, and divide the bar cost by that figure for the true material cost per part. #### What is bar remnant in Swiss and screw machine work? **Answer:** Remnant is the short end of a bar the machine cannot feed or hold to make another full part. It depends on the bar feeder, guide bushing and collet configuration. Over many bars it is a real cost, so it should be in the yield calculation and, where possible, tracked in the ERP. #### Should the quote use finished weight times price per pound? **Answer:** No. That ignores kerf, face-off, remnant and scrap, and it understates cost most on short parts. Use bar-based costing: price per bar divided by realistic good parts per bar. ## Related Slugs - how-to-quote-swiss-turned-parts - manufacturing-costing-methods-comparison - syteline-costing-variance-investigation - product-cost-management-guide ## Search terms bar stock cost estimating, parts per bar calculation, screw machine material cost, bar remnant swiss machine, cutoff kerf face-off stock, bar stock yield calculator --- Talk to an engineer: https://netray.co/contact?intent=erp_ai | Machine catalog: https://netray.co/agent/catalog.json