{"id":7518,"date":"2026-10-26T06:03:46","date_gmt":"2026-10-26T06:03:46","guid":{"rendered":"https:\/\/uplastech.com\/injection-molding-cost-per-part\/"},"modified":"2026-10-26T07:41:42","modified_gmt":"2026-10-26T07:41:42","slug":"injection-molding-cost-per-part","status":"publish","type":"post","link":"https:\/\/uplastech.com\/fr\/injection-molding-cost-per-part\/","title":{"rendered":"Injection Molding Cost per Part: How the Price Is Really Built"},"content":{"rendered":"<style>\n.upl-blog{font-size:17px;line-height:1.78;color:#1f2937}\n.upl-blog p{margin:0 0 18px}\n.upl-blog h2{font-size:26px;line-height:1.3;color:#0b2b33;margin:46px 0 14px;font-weight:700;letter-spacing:-.015em}\n.upl-blog h3{font-size:19.5px;color:#0d3b47;margin:28px 0 10px;font-weight:700}\n.upl-blog ul,.upl-blog ol{margin:0 0 20px;padding-left:22px}\n.upl-blog li{margin:0 0 9px}\n.upl-blog figure{margin:0 0 34px}\n.upl-blog figure img{width:100%;height:auto;display:block;border-radius:10px}\n.upl-blog figcaption{font-size:13px;color:#6b7280;margin-top:10px;line-height:1.5}\n.upl-blog .toc{background:none;border:0;border-radius:0;padding:0;margin:0 0 34px}\n.upl-blog .toc .lwptoc{margin:0}\n.upl-blog .toc h4{margin:0 0 10px;font-size:13px;letter-spacing:.1em;text-transform:uppercase;color:#0d5563}\n.upl-blog .toc ol{margin:0;padding-left:18px;font-size:14.5px}\n.upl-blog .toc li{margin-bottom:6px}\n.upl-blog table{width:100%;border-collapse:collapse;font-size:14.5px;margin:0 0 10px}\n.upl-blog th{background:#0d3b47;color:#fff;text-align:left;padding:11px 13px;font-weight:600;font-size:13.5px;border:0}\n.upl-blog td{padding:11px 13px;border:0;border-bottom:1px solid #e8ebed;vertical-align:top}\n.upl-blog tbody tr:nth-child(even){background:#fafbfc}\n.upl-blog .tablecap{font-size:12.5px;color:#6b7280;margin:0 0 30px}\n.upl-blog .myth{background:#fff8ef;border:1px solid #f6ddbd;border-radius:8px;padding:16px 20px;margin:0 0 26px;font-size:15.5px}\n.upl-blog .myth b{color:#a85c10}\n.upl-blog .callout{background:#f2f8f9;border-radius:8px;padding:18px 22px;margin:0 0 26px;font-size:15.5px;border-left:3px solid #14707f}\n.upl-blog .faq h3{border-top:1px solid #eceff1;padding-top:22px;margin-top:0;font-size:18px}\n.upl-blog .faq h3:first-of-type{border-top:0;padding-top:0}\n.upl-blog .cta{background:linear-gradient(135deg,#0b2b33,#0d5563);color:#fff;border-radius:12px;padding:34px;margin:48px 0 30px}\n.upl-blog .cta h2,.upl-blog .cta .cta-h{color:#fff;margin:0 0 10px;font-size:24px;font-weight:700;line-height:1.3}\n.upl-blog .cta p{color:#c9dee3;margin:0 0 20px;font-size:16px}\n.upl-blog .btn{display:inline-block;background:#e07a1f;color:#fff;text-decoration:none;font-weight:700;padding:13px 26px;border-radius:8px;font-size:15.5px}\n.upl-blog .rel{border-top:1px solid #e8ebed;margin-top:40px;padding-top:26px}\n.upl-blog .rel h4{font-size:13px;letter-spacing:.1em;text-transform:uppercase;color:#6b7280;margin:0 0 14px}\n.upl-blog .rel ul{list-style:none;padding:0;margin:0}\n.upl-blog .rel li{padding:11px 0;border-bottom:1px dashed #e8ebed}\n.upl-blog .rel a{text-decoration:none;font-weight:600;font-size:15.5px}\n@media(max-width:640px){.upl-blog h2{font-size:22px}.upl-blog table{font-size:13px}.upl-blog .cta{padding:24px}}\n\/* \u5355\u7bc7\u9875\u9690\u85cf WhatsApp \u81ea\u52a8\u5c55\u5f00\u7684\u95ee\u5019\u5361\uff0c\u53ea\u4fdd\u7559\u5706\u5f62\u6c14\u6ce1\uff0c\u907f\u514d\u906e\u6321\u4fa7\u680f\u8be2\u76d8\u63d0\u4ea4\u6309\u94ae *\/\nbody.single-post .ht_ctc_chat_greetings_box{display:none !important}\n<\/style>\n<div class=\"upl-blog\">\n<figure>\n<img fetchpriority=\"high\" decoding=\"async\" src=\"https:\/\/uplastech.com\/wp-content\/uploads\/2026\/10\/im-cost-parts-bin.jpg\" alt=\"Freshly moulded plastic components in a collection bin beside an injection molding machine\" width=\"1536\" height=\"909\"><figcaption>Every part in this bin has a price that was fixed before the tool was cut \u2014 by its wall thickness, its cycle time and how many cavities the tool has.<\/figcaption><\/figure>\n<div class=\"toc\"><\/div>\n<h2 id=\"structure\">How a piece price is actually built<\/h2>\n<p>A moulded part price is not a market rate and it is not a guess. It is the sum of five cost blocks divided by the number of good parts you get per hour. Once you can see the structure, you can see which levers are worth pulling \u2014 and, more importantly, which quotation is quietly unrealistic.<\/p>\n<div class=\"callout\">\n<p><strong>The core equation.<\/strong><\/p>\n<p>Piece price = (Machine rate \u00d7 cycle time \u00f7 cavities + Material per part + Runner and scrap loss + Secondary operations + Packaging) \u00f7 Yield, plus tool amortisation if it is bundled.<\/p>\n<p>Every number in that equation is either a design decision or a commercial decision. None of them is fixed by the market.<\/p>\n<\/div>\n<table>\n<thead>\n<tr>\n<th>Cost block<\/th>\n<th>Typical share of piece price<\/th>\n<th>Set by<\/th>\n<th>Leverage<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Mat\u00e9riau<\/td>\n<td>35 \u2013 60 %<\/td>\n<td>Resin choice, part weight, runner weight<\/td>\n<td>Haut<\/td>\n<\/tr>\n<tr>\n<td>Machine time<\/td>\n<td>20 \u2013 40 %<\/td>\n<td>Cycle time, cavitation, tonnage<\/td>\n<td>Haut<\/td>\n<\/tr>\n<tr>\n<td>Labour<\/td>\n<td>5 \u2013 15 %<\/td>\n<td>Automation level, secondary ops<\/td>\n<td>Moyen<\/td>\n<\/tr>\n<tr>\n<td>Scrap and start-up<\/td>\n<td>2 \u2013 10 %<\/td>\n<td>Process stability, quality standard<\/td>\n<td>Moyen<\/td>\n<\/tr>\n<tr>\n<td>Packaging and freight<\/td>\n<td>2 \u2013 8 %<\/td>\n<td>Part size, protection required<\/td>\n<td>Faible<\/td>\n<\/tr>\n<tr>\n<td>Overhead and margin<\/td>\n<td>10 \u2013 20 %<\/td>\n<td>Supplier's cost structure<\/td>\n<td>Faible<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Shares are for a mid-size engineering part in the 20 \u2013 300 g range, produced on a 200 \u2013 500 t machine. Small precision parts shift towards machine time; large commodity parts shift towards material.<\/p>\n<p>Notice that material and machine time together are 60 \u2013 90 % of the price. That is why almost every meaningful cost reduction comes from changing the part weight, the wall thickness, the cycle time or the cavitation \u2014 not from negotiating the supplier's margin.<\/p>\n<h2 id=\"machine\">The machine rate, and why tonnage is not the main driver<\/h2>\n<p>The machine rate is what it costs to have a machine occupied for an hour: depreciation, energy, maintenance, floor space, and the operator and supervision attributable to it. It rises with tonnage, but not proportionally, and it rises steeply with special features.<\/p>\n<table>\n<thead>\n<tr>\n<th>Clamp force<\/th>\n<th>Indicative hourly rate<\/th>\n<th>Typical part range<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>50 \u2013 100 t<\/td>\n<td>$18 \u2013 28 \/ h<\/td>\n<td>Small precision parts, connectors, small gears<\/td>\n<\/tr>\n<tr>\n<td>100 \u2013 200 t<\/td>\n<td>$25 \u2013 40 \/ h<\/td>\n<td>Handheld housings, caps, small enclosures<\/td>\n<\/tr>\n<tr>\n<td>200 \u2013 350 t<\/td>\n<td>$35 \u2013 55 \/ h<\/td>\n<td>Mid-size housings, automotive trim, appliance parts<\/td>\n<\/tr>\n<tr>\n<td>350 \u2013 600 t<\/td>\n<td>$50 \u2013 80 \/ h<\/td>\n<td>Large enclosures, crates, automotive under-bonnet<\/td>\n<\/tr>\n<tr>\n<td>600 \u2013 1,000 t<\/td>\n<td>$75 \u2013 120 \/ h<\/td>\n<td>Large panels, pallets, bulk containers<\/td>\n<\/tr>\n<tr>\n<td>1,000 t +<\/td>\n<td>$110 \u2013 180 \/ h<\/td>\n<td>Very large parts, two-shot large parts<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Indicative European and North American rates for a standard hydraulic or servo machine. Asian rates are typically 40 \u2013 60 % of these; the structure is the same.<\/p>\n<p>Two things surprise buyers here. First, the rate difference between a 200 t and a 400 t machine is much smaller than the tonnage ratio suggests \u2014 roughly 1.4\u00d7 for double the tonnage. So running a part on a machine that is somewhat too large is wasteful but not catastrophic; running it on a machine with the wrong <em>shot capacity<\/em> is worse.<\/p>\n<p>Second, the shot-size rule matters more than the tonnage rule. A machine's barrel and screw are sized for a shot range, typically 20 \u2013 80 % of the maximum shot capacity. Running a 30 g part on a machine with a 1,000 g maximum shot means the melt residence time in the barrel is very long, which degrades the material, and the process becomes unstable. The correct machine is the smallest one that fits the clamp force and the shot size, not the biggest one that is free.<\/p>\n<h3>How much clamp force do you actually need?<\/h3>\n<p>Clamp force has to exceed the separating force from injection pressure acting on the projected area of the part plus the runner:<\/p>\n<div class=\"callout\">\n<p><strong>Clamp force (t) = Projected area (cm\u00b2) \u00d7 Cavity pressure (kg\/cm\u00b2) \u00f7 1,000<\/strong><\/p>\n<p>For a 120 cm\u00b2 part at 400 kg\/cm\u00b2 cavity pressure: 120 \u00d7 400 \u00f7 1,000 = <strong>48 t<\/strong>. Add a 20 % safety margin and you need about 60 t \u2014 not the 250 t that \"feels right\" for a housing.<\/p>\n<\/div>\n<p>Cavity pressure is the number people get wrong. It is not the injection pressure at the nozzle; it is the pressure inside the cavity after packing. Typical values are 300 \u2013 500 kg\/cm\u00b2 for commodity resins, 500 \u2013 800 for engineering resins, and up to 1,000 for precision work. Overestimating it costs money in machine time; underestimating it costs money in flash.<\/p>\n<h2 id=\"cycle\">Cycle time: the four phases and which one you can shorten<\/h2>\n<p>Cycle time is the clock that multiplies the machine rate. It has four phases, and they are not equally controllable.<\/p>\n<table>\n<thead>\n<tr>\n<th>Phase<\/th>\n<th>Typical share<\/th>\n<th>What sets it<\/th>\n<th>Can you shorten it?<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Injection and fill<\/td>\n<td>5 \u2013 15 %<\/td>\n<td>Flow rate, wall thickness, flow length<\/td>\n<td>Yes \u2014 faster fill, thinner wall, better gate<\/td>\n<\/tr>\n<tr>\n<td>Packing and holding<\/td>\n<td>10 \u2013 25 %<\/td>\n<td>Gate freeze time, part thickness<\/td>\n<td>Partly \u2014 bigger gate freezes later but needs less time<\/td>\n<\/tr>\n<tr>\n<td>Refroidissement<\/td>\n<td>50 \u2013 70 %<\/td>\n<td>Wall thickness squared, coolant temperature, tool steel conductivity<\/td>\n<td>Yes \u2014 this is where the money is<\/td>\n<\/tr>\n<tr>\n<td>Mould open, eject, close<\/td>\n<td>8 \u2013 20 %<\/td>\n<td>Machine speed, robot, ejection stroke<\/td>\n<td>Yes \u2014 dry cycle optimisation, robot take-out<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Cooling dominates, and it scales with the square of wall thickness. That single relationship explains more about moulding economics than anything else in this article.<\/p>\n<h3>The cooling rule of thumb<\/h3>\n<p>Cooling time is roughly proportional to the square of the thickest wall section. Doubling wall thickness quadruples cooling time. Halving it cuts cooling to a quarter. For a part where cooling is 60 % of a 30 s cycle, dropping the wall from 3 mm to 2.4 mm can take the cycle from 30 s to about 23 s \u2014 a 23 % reduction in machine time on every part, forever.<\/p>\n<table>\n<thead>\n<tr>\n<th>Wall thickness (ABS)<\/th>\n<th>Indicative cooling time<\/th>\n<th>Indicative total cycle<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1.0 mm<\/td>\n<td>2.5 s<\/td>\n<td>8 \u2013 10 s<\/td>\n<\/tr>\n<tr>\n<td>1.5 mm<\/td>\n<td>5 s<\/td>\n<td>12 \u2013 15 s<\/td>\n<\/tr>\n<tr>\n<td>2.0 mm<\/td>\n<td>8.5 s<\/td>\n<td>17 \u2013 21 s<\/td>\n<\/tr>\n<tr>\n<td>2.5 mm<\/td>\n<td>13 s<\/td>\n<td>23 \u2013 28 s<\/td>\n<\/tr>\n<tr>\n<td>3.0 mm<\/td>\n<td>19 s<\/td>\n<td>31 \u2013 38 s<\/td>\n<\/tr>\n<tr>\n<td>4.0 mm<\/td>\n<td>33 s<\/td>\n<td>50 \u2013 60 s<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Cooling time calculated for ABS at 80 \u00b0C tool temperature, 230 \u00b0C melt, ejecting at 90 \u00b0C. Total cycle adds fill, pack, hold and mould movement.<\/p>\n<figure>\n<img decoding=\"async\" src=\"https:\/\/uplastech.com\/wp-content\/uploads\/2026\/10\/im-cost-cycle-panel.jpg\" alt=\"Injection moulding machine control panel showing cycle time, injection pressure and barrel temperature zones\" width=\"1536\" height=\"909\"><figcaption>The cycle time on this screen is the number that multiplies the machine rate on every part you will ever buy. It is set by the wall thickness on the drawing, not by the machine.<\/figcaption><\/figure>\n<p>This is the single most useful table in this article. A designer who thickens a wall from 2 mm to 3 mm to \"make it stronger\" has just increased the piece price by roughly 80 % \u2014 and a ribbed 2 mm wall would have been stiffer than the 3 mm flat wall anyway.<\/p>\n<h3>What else moves cycle time<\/h3>\n<ul>\n<li><strong>Tool steel and cooling channel design.<\/strong> Beryllium copper inserts in hot spots, conformal cooling, and baffles in deep cores can cut cooling time 20 \u2013 40 % on difficult parts. It costs more up front and pays back within months at volume.<\/li>\n<li><strong>Coolant temperature.<\/strong> Colder water cools faster but increases warpage and internal stress. There is an optimum, not a minimum.<\/li>\n<li><strong>Robot take-out.<\/strong> A robot that removes the part during mould close removes the ejector-return time from the cycle. On a 20 s cycle this can save 1.5 \u2013 3 s \u2014 10 % of the price.<\/li>\n<li><strong>Hot runner.<\/strong> Eliminates sprue cooling and degating, typically saving 3 \u2013 8 s per cycle and removing the runner from the material cost.<\/li>\n<\/ul>\n<h2 id=\"cavitation\">Cavitation: the single biggest lever<\/h2>\n<p>Machine time per part is the cycle time divided by the number of cavities. Going from one cavity to four cuts the machine cost per part by 75 %. Nothing else in moulding has that leverage.<\/p>\n<table>\n<thead>\n<tr>\n<th>Cavities<\/th>\n<th>Machine cost per part (30 s cycle, $45\/h)<\/th>\n<th>Tool cost multiplier<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1<\/td>\n<td>$0.375<\/td>\n<td>1.0\u00d7<\/td>\n<\/tr>\n<tr>\n<td>2<\/td>\n<td>$0.188<\/td>\n<td>1.6\u00d7<\/td>\n<\/tr>\n<tr>\n<td>4<\/td>\n<td>$0.094<\/td>\n<td>2.4\u00d7<\/td>\n<\/tr>\n<tr>\n<td>8<\/td>\n<td>$0.047<\/td>\n<td>3.8\u00d7<\/td>\n<\/tr>\n<tr>\n<td>16<\/td>\n<td>$0.023<\/td>\n<td>6.0\u00d7<\/td>\n<\/tr>\n<tr>\n<td>32<\/td>\n<td>$0.012<\/td>\n<td>9.5\u00d7<\/td>\n<\/tr>\n<tr>\n<td>64<\/td>\n<td>$0.006<\/td>\n<td>15\u00d7<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Tool cost multipliers are indicative for a simple part with no side actions. The multiplier is lower for complex tools because the base cost dominates.<\/p>\n<p>So why is any tool single-cavity? Four reasons, and they are all real:<\/p>\n<ul>\n<li><strong>Volume.<\/strong> The extra tool cost has to be paid back by the machine-time saving. At 2,000 parts a year, an 8-cavity tool never pays back.<\/li>\n<li><strong>Tolerance.<\/strong> Cavities are not identical. On a \u00b10.05 mm dimension, eight cavities means eight processes that all have to be capable.<\/li>\n<li><strong>Part size.<\/strong> A large part may not fit more than one cavity inside the clamp force available.<\/li>\n<li><strong>Risk.<\/strong> One cavity can be replaced; eight cavities means eight times the tool maintenance and a bigger single point of failure.<\/li>\n<\/ul>\n<p>The payback calculation is simple and worth doing explicitly:<\/p>\n<div class=\"callout\">\n<p><strong>Cavitation payback = (Tool cost at N cavities \u2212 Tool cost at 1 cavity) \u00f7 (Machine cost per part at 1 cavity \u2212 Machine cost per part at N cavities)<\/strong><\/p>\n<p>For the example above, moving from 1 to 4 cavities costs about 1.4\u00d7 extra tool cost \u2014 say $12,000 on a $30,000 tool \u2014 and saves $0.281 per part. Payback at 12,000 \u00f7 0.281 \u2248 <strong>42,700 parts<\/strong>. Below that annual volume, stay single-cavity or go to two.<\/p>\n<\/div>\n<h2 id=\"material\">Material cost and the runner you pay for twice<\/h2>\n<p>Material is usually the largest single block, and it is the one buyers most often assume is fixed. It is not: it depends on part weight, wall thickness, runner design and how much regrind the supplier can legitimately use.<\/p>\n<h3>The shot weight calculation<\/h3>\n<p>You pay for the shot, not the part. A shot is the part plus the runner plus the sprue:<\/p>\n<div class=\"callout\">\n<p><strong>Material cost per part = (Part weight + Runner weight per part) \u00d7 Resin price per kg \u00f7 1,000<\/strong><\/p>\n<p>A 45 g part with a 12 g runner per part, in ABS at $2.40\/kg: (45 + 12) \u00d7 2.40 \u00f7 1,000 = <strong>$0.137<\/strong>. The runner alone costs $0.029 \u2014 21 % of the material cost, for material that becomes scrap.<\/p>\n<\/div>\n<p>Hot runners remove that cost almost entirely. On the example above, a hot runner saves $0.029 per part in material plus a few seconds of cycle time. At 500,000 parts a year, that is $14,500 in material alone \u2014 which is why hot runner tools pay back quickly at volume and never pay back at low volume.<\/p>\n<h3>Regrind<\/h3>\n<p>Most suppliers will blend regrind back into the virgin material, typically 10 \u2013 25 % for commodity resins and 0 % for medical, food-contact and optical parts. Regrind is cheaper than virgin resin, so a supplier who uses it can quote lower \u2014 but regrind degrades with each pass, and above about 25 % the mechanical properties and colour consistency start to drift.<\/p>\n<p>The commercial point: if your drawing says \"100 % virgin\", you are paying for it, and you should know that. If it says nothing, you are probably getting 10 \u2013 20 % regrind and you should confirm the limit in writing.<\/p>\n<table>\n<thead>\n<tr>\n<th>Resin<\/th>\n<th>Indicative price band (USD\/kg)<\/th>\n<th>Density (g\/cm\u00b3)<\/th>\n<th>Note<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>PP homopolymer<\/td>\n<td>1.1 \u2013 1.5<\/td>\n<td>0.90 \u2013 0.91<\/td>\n<td>Cheapest per part because of low density<\/td>\n<\/tr>\n<tr>\n<td>PEHD<\/td>\n<td>1.2 \u2013 1.6<\/td>\n<td>0.94 \u2013 0.96<\/td>\n<td>Commodity, stable pricing<\/td>\n<\/tr>\n<tr>\n<td>HIPS<\/td>\n<td>1.4 \u2013 1.8<\/td>\n<td>1.04 \u2013 1.05<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<tr>\n<td>ABS<\/td>\n<td>2.0 \u2013 2.8<\/td>\n<td>1.04 \u2013 1.07<\/td>\n<td>Wide range by grade and colour<\/td>\n<\/tr>\n<tr>\n<td>PC<\/td>\n<td>3.0 \u2013 4.5<\/td>\n<td>1.20<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<tr>\n<td>PC\/ABS<\/td>\n<td>2.8 \u2013 4.0<\/td>\n<td>1.13 \u2013 1.15<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<tr>\n<td>PMMA<\/td>\n<td>2.6 \u2013 3.6<\/td>\n<td>1.18 \u2013 1.19<\/td>\n<td>Optical grades cost more<\/td>\n<\/tr>\n<tr>\n<td>PA6<\/td>\n<td>2.4 \u2013 3.4<\/td>\n<td>1.13<\/td>\n<td>Price moves with caprolactam<\/td>\n<\/tr>\n<tr>\n<td>PA66<\/td>\n<td>2.8 \u2013 4.0<\/td>\n<td>1.14<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<tr>\n<td>POM<\/td>\n<td>2.6 \u2013 3.8<\/td>\n<td>1.41<\/td>\n<td>High density, so higher cost per part<\/td>\n<\/tr>\n<tr>\n<td>PBT<\/td>\n<td>2.8 \u2013 4.2<\/td>\n<td>1.31<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<tr>\n<td>PA66 + 30 % GF<\/td>\n<td>3.0 \u2013 4.2<\/td>\n<td>1.36<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<tr>\n<td>PPS + 40 % GF<\/td>\n<td>9 \u2013 16<\/td>\n<td>1.66<\/td>\n<td>High-performance, high density<\/td>\n<\/tr>\n<tr>\n<td>PEEK<\/td>\n<td>60 \u2013 110<\/td>\n<td>1.30<\/td>\n<td>Specialty only<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Indicative 2026 bands for standard moulding grades in tonne quantities. Colour masterbatch, UV stabilisers, flame retardants and glass loading all move the price.<\/p>\n<p>Density is the hidden variable. POM at $3.20\/kg looks cheaper than PC at $4.00\/kg until you notice POM is 1.41 g\/cm\u00b3 and PC is 1.20 \u2014 per cubic centimetre of part, POM costs $4.51 and PC costs $4.80, which is a much smaller gap. Always compare cost per part volume, not cost per kilogram.<\/p>\n<h2 id=\"scrap\">Scrap, start-up and the parts you never see<\/h2>\n<p>No process produces 100 % good parts. The yield factor is the ratio of saleable parts to parts moulded, and it hides inside every quotation whether or not the supplier admits it.<\/p>\n<table>\n<thead>\n<tr>\n<th>Source of loss<\/th>\n<th>Typical yield impact<\/th>\n<th>Notes<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Start-up \/ process settling<\/td>\n<td>10 \u2013 40 shots per run<\/td>\n<td>Worse on cold tools and on colour changes<\/td>\n<\/tr>\n<tr>\n<td>Steady-state rejects<\/td>\n<td>0.5 \u2013 3 %<\/td>\n<td>Cosmetic defects, short shots, flash<\/td>\n<\/tr>\n<tr>\n<td>First-off and inspection samples<\/td>\n<td>5 \u2013 20 parts per run<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<tr>\n<td>Machine downtime<\/td>\n<td>2 \u2013 8 % of scheduled hours<\/td>\n<td>Mould changes, maintenance, material changes<\/td>\n<\/tr>\n<tr>\n<td>Purge and colour change<\/td>\n<td>2 \u2013 10 kg per change<\/td>\n<td>Significant on short runs<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">On a 10,000-part run, a 30-shot start-up and 1.5 % rejects is about 180 parts of loss \u2014 1.8 % of the order, added to the price.<\/p>\n<p>This is why short runs cost more per part than long runs, and why the same part quoted at 5,000 and at 50,000 comes back with different prices. It is not arbitrary; the start-up loss is spread over ten times fewer parts.<\/p>\n<p>It is also why cosmetic standard matters so much commercially. A part with a strict cosmetic requirement may run at 3 % rejects where the same part at a relaxed standard runs at 0.5 %. That 2.5 % difference is real money, and it is entirely a decision made on the drawing.<\/p>\n<h2 id=\"labour\">Labour, packaging and freight<\/h2>\n<p>Labour is smaller than most buyers expect on an automated machine and larger than they expect on a manual one. A single operator can run several machines if parts drop free or are robot-taken; a part that needs manual loading of inserts, manual degating or manual inspection is a different cost structure.<\/p>\n<table>\n<thead>\n<tr>\n<th>Operation<\/th>\n<th>Typical cost per part<\/th>\n<th>Notes<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Fully automatic, part drops free<\/td>\n<td>$0.00 \u2013 0.01<\/td>\n<td>One operator to several machines<\/td>\n<\/tr>\n<tr>\n<td>Robot take-out and stacking<\/td>\n<td>$0.01 \u2013 0.03<\/td>\n<td>Robot amortised over volume<\/td>\n<\/tr>\n<tr>\n<td>Manual degating (snip or saw)<\/td>\n<td>$0.02 \u2013 0.08<\/td>\n<td>Scales with number of gates<\/td>\n<\/tr>\n<tr>\n<td>Manual insert loading<\/td>\n<td>$0.05 \u2013 0.25<\/td>\n<td>Per insert, per cycle<\/td>\n<\/tr>\n<tr>\n<td>Visual inspection, 100 %<\/td>\n<td>$0.03 \u2013 0.15<\/td>\n<td>Driven by cosmetic standard<\/td>\n<\/tr>\n<tr>\n<td>Assembly or ultrasonic welding<\/td>\n<td>$0.10 \u2013 0.60<\/td>\n<td>Often a separate line item<\/td>\n<\/tr>\n<tr>\n<td>Printing, painting, laser marking<\/td>\n<td>$0.08 \u2013 0.50<\/td>\n<td>\u2014<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Indicative for European labour rates. Asian rates are substantially lower but the structure and the ranking are the same.<\/p>\n<p>Packaging is small per part but not negligible: an inner bag, a divider layer, an outer carton and a pallet add up to $0.02 \u2013 0.15 per part depending on how fragile the part is and how the customer's warehouse receives goods. Freight is priced per kilogram and per cubic metre, so a part that nests well ships cheaper than one that does not \u2014 which is a design decision made years before anyone thinks about freight.<\/p>\n<h2 id=\"tool\">Tool amortisation: when it belongs in the price<\/h2>\n<p>There are two legitimate commercial models and one bad one.<\/p>\n<p><strong>Separate tool, separate parts.<\/strong> The customer pays for the tool as a capital item and pays a piece price that reflects only conversion and material. This is the cleanest model: the customer owns an asset, the piece price is comparable across suppliers, and if they move the tool the price does not change.<\/p>\n<p><strong>Amortised tool.<\/strong> The tool cost is spread across a committed volume and included in the piece price. This is legitimate when the customer cannot fund the tool up front, and it is normal for very large programmes. The piece price is higher, and the customer should receive a price reduction once the amortisation is complete \u2014 which should be written into the agreement.<\/p>\n<p><strong>The bad one.<\/strong> Tool cost buried in the piece price with no stated amortisation volume and no price reduction later. The customer pays for the tool many times over and never owns it. This is the most common commercial problem in injection moulding, and the defence is simple: ask for the tool cost and the amortisation volume in writing, separately.<\/p>\n<div class=\"callout\">\n<p><strong>What a transparent quotation looks like.<\/strong> Tool cost stated separately with cavity count and steel type; piece price broken into material, machine time and secondary operations; the assumed cycle time; the cavitation; the resin grade and price basis; the packaging cost; and the validity period. If a supplier will not show the cycle time and cavitation, you cannot compare their price to anyone else's.<\/p>\n<\/div>\n<h2 id=\"worked\">Three worked examples<\/h2>\n<p>Numbers make this concrete. All three use a $45\/h machine rate, ABS at $2.40\/kg, and a 2 % yield loss.<\/p>\n<h3>Example A: 45 g enclosure, 4 cavities<\/h3>\n<table>\n<thead>\n<tr>\n<th>Line item<\/th>\n<th>Calculation<\/th>\n<th>Cost per part<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Material (part)<\/td>\n<td>0.045 kg \u00d7 $2.40<\/td>\n<td>$0.108<\/td>\n<\/tr>\n<tr>\n<td>Material (runner, 8 g\/part)<\/td>\n<td>0.008 kg \u00d7 $2.40<\/td>\n<td>$0.019<\/td>\n<\/tr>\n<tr>\n<td>Machine time<\/td>\n<td>28 s \u00f7 4 cavities \u00d7 $45\/3,600 s<\/td>\n<td>$0.0875<\/td>\n<\/tr>\n<tr>\n<td>Degating and inspection<\/td>\n<td>Manual snip + visual<\/td>\n<td>$0.045<\/td>\n<\/tr>\n<tr>\n<td>Emballage<\/td>\n<td>Bag, carton, pallet<\/td>\n<td>$0.030<\/td>\n<\/tr>\n<tr>\n<td>Subtotal<\/td>\n<td>\u2014<\/td>\n<td>$0.2895<\/td>\n<\/tr>\n<tr>\n<td>Yield adjustment<\/td>\n<td>\u00f7 0.98<\/td>\n<td>$0.295<\/td>\n<\/tr>\n<tr>\n<td>Overhead and margin (15 %)<\/td>\n<td>\u00d7 1.15<\/td>\n<td><strong>$0.340<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">A typical consumer electronics enclosure. Material is 37 % of the price, machine time 26 %.<\/p>\n<h3>Example B: same part, 2.0 mm wall instead of 3.0 mm<\/h3>\n<table>\n<thead>\n<tr>\n<th>Line item<\/th>\n<th>3.0 mm wall<\/th>\n<th>2.0 mm wall<\/th>\n<th>Change<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Part weight<\/td>\n<td>45 g<\/td>\n<td>32 g<\/td>\n<td>\u221229 %<\/td>\n<\/tr>\n<tr>\n<td>Material cost<\/td>\n<td>$0.127<\/td>\n<td>$0.091<\/td>\n<td>\u2212$0.036<\/td>\n<\/tr>\n<tr>\n<td>Dur\u00e9e du cycle<\/td>\n<td>28 s<\/td>\n<td>19 s<\/td>\n<td>\u221232 %<\/td>\n<\/tr>\n<tr>\n<td>Machine cost per part<\/td>\n<td>$0.0875<\/td>\n<td>$0.0594<\/td>\n<td>\u2212$0.028<\/td>\n<\/tr>\n<tr>\n<td>Total piece price<\/td>\n<td>$0.340<\/td>\n<td>$0.253<\/td>\n<td><strong>\u221226 %<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">Same tool, same material, same machine. A 1 mm wall reduction is worth 26 % of the piece price \u2014 and with ribs, the part is stiffer than the original.<\/p>\n<h3>Example C: 12 g connector body, 16 cavities vs 4 cavities<\/h3>\n<table>\n<thead>\n<tr>\n<th>Line item<\/th>\n<th>4 cavities<\/th>\n<th>16 cavities<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Dur\u00e9e du cycle<\/td>\n<td>16 s<\/td>\n<td>22 s<\/td>\n<\/tr>\n<tr>\n<td>Machine cost per part<\/td>\n<td>$0.050<\/td>\n<td>$0.017<\/td>\n<\/tr>\n<tr>\n<td>Material per part (hot runner)<\/td>\n<td>$0.030<\/td>\n<td>$0.030<\/td>\n<\/tr>\n<tr>\n<td>Inspection and packaging<\/td>\n<td>$0.020<\/td>\n<td>$0.020<\/td>\n<\/tr>\n<tr>\n<td>Piece price before margin<\/td>\n<td>$0.100<\/td>\n<td>$0.067<\/td>\n<\/tr>\n<tr>\n<td>Tool cost<\/td>\n<td>$28,000<\/td>\n<td>$95,000<\/td>\n<\/tr>\n<tr>\n<td>Annual volume<\/td>\n<td>400,000<\/td>\n<td>400,000<\/td>\n<\/tr>\n<tr>\n<td>Annual saving<\/td>\n<td>\u2014<\/td>\n<td>$13,200<\/td>\n<\/tr>\n<tr>\n<td>Tool payback<\/td>\n<td>\u2014<\/td>\n<td><strong>5.1 years<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"tablecap\">The bigger tool looks obviously better and is obviously wrong at this volume. The payback is longer than most programmes last.<\/p>\n<p>These three examples cover the three decisions that set 80 % of a moulded part's price: wall thickness, cavitation and wall thickness again. If you only optimise one thing before cutting steel, optimise the wall.<\/p>\n<h2 id=\"reduce\">Twelve ways to cut the piece price<\/h2>\n<p>Ranked roughly by impact per unit of effort.<\/p>\n<ol>\n<li><strong>Reduce wall thickness to the minimum that meets the structural requirement.<\/strong> Cooling scales with thickness squared, and weight scales linearly. Biggest single lever, no tool cost.<\/li>\n<li><strong>Add ribs instead of thickness.<\/strong> Stiffness per gram is far higher, and ribs do not lengthen cooling.<\/li>\n<li><strong>Increase cavitation to the volume-justified level.<\/strong> Do the payback calculation explicitly rather than accepting the supplier's default.<\/li>\n<li><strong>Convert to a hot runner.<\/strong> Removes runner material and several seconds of cycle. Pays back at volume, never at low volume.<\/li>\n<li><strong>Move the gate to shorten the flow path.<\/strong> Less injection pressure needed, smaller machine, shorter fill time.<\/li>\n<li><strong>Choose a lower-density resin at equal performance.<\/strong> PP at 0.905 g\/cm\u00b3 delivers more parts per kilogram than ABS at 1.05.<\/li>\n<li><strong>Eliminate secondary operations by design.<\/strong> Mould the snap fit instead of adding a screw; mould the living hinge instead of adding a pin.<\/li>\n<li><strong>Relax the cosmetic standard where it does not matter.<\/strong> A hidden surface at SPI B-3 instead of A-2 removes rejects and polishing cost.<\/li>\n<li><strong>Consolidate parts.<\/strong> One moulded part replacing three assembled parts usually wins even if the moulded part is more expensive than any one of them.<\/li>\n<li><strong>Improve tool cooling.<\/strong> Beryllium copper inserts or conformal cooling in hot spots, 20 \u2013 40 % cooling reduction on difficult parts.<\/li>\n<li><strong>Add robot take-out.<\/strong> Removes 1.5 \u2013 3 s from the cycle and stabilises quality.<\/li>\n<li><strong>Commit to a blanket order with scheduled releases.<\/strong> Gives the supplier a reason to keep the tool set up and material in stock, typically worth 10 \u2013 20 % on the piece price.<\/li>\n<\/ol>\n<h2 id=\"traps\">Quotation traps that look like savings<\/h2>\n<p>Five patterns that produce a low quote and a high total cost.<\/p>\n<p><strong>A piece price with the tool hidden inside it.<\/strong> You cannot compare it to anything, you never own the tool, and there is no price reduction when the amortisation ends. Ask for the tool cost separately even if you intend to amortise.<\/p>\n<p><strong>A cycle time that is physically impossible.<\/strong> If the quoted cycle time is shorter than the cooling time the wall thickness allows, the supplier is either going to run it hot and ship warped parts, or they made an error they will recover later. Check the cycle time against the wall thickness table.<\/p>\n<p><strong>A cavitation that does not match the volume.<\/strong> An 8-cavity tool for a 3,000-part order means you paid for capacity you will never use. Ask why that cavity count was chosen.<\/p>\n<p><strong>A material grade that is not the one on the drawing.<\/strong> \"ABS\" covers a wide range; a low-cost high-flow grade may not meet your impact requirement. Specify the grade and ask for the material certificate.<\/p>\n<p><strong>No stated yield or cosmetic standard.<\/strong> A price with no reject allowance is a price that will be renegotiated after the first production run. Agree the cosmetic standard and the acceptable reject rate in writing.<\/p>\n<h2 id=\"faq\">Frequently asked questions<\/h2>\n<div class=\"faq\">\n<h3>What does injection molding cost per part?<\/h3>\n<p>Anywhere from a few cents to several dollars. A 12 g connector body in high volume can be $0.07; a 300 g glass-filled housing at low volume can be $8.00. The two numbers that matter most are part weight and annual volume \u2014 everything else is a modifier.<\/p>\n<h3>Why is my 5,000-part order so much more expensive per part than the 50,000-part quote?<\/h3>\n<p>Three reasons: start-up loss is spread over ten times fewer parts, the supplier may run fewer cavities or a slower process to protect a short run, and the setup and material change costs are fixed. A 30 \u2013 60 % difference between a 5,000 and a 50,000 piece price is normal.<\/p>\n<h3>Is a hot runner worth it?<\/h3>\n<p>At volume, almost always. It removes the runner material, saves several seconds of cycle time and eliminates degating. The payback is typically 6 \u2013 18 months above about 200,000 parts a year. Below 50,000 parts a year it usually never pays back, and the additional maintenance becomes a liability.<\/p>\n<h3>How much does wall thickness really affect price?<\/h3>\n<p>Enormously. Going from 3 mm to 2 mm on the same part typically cuts the piece price by 25 \u2013 30 %, because both the material and the cooling time fall. It is the largest single lever available to a designer and it costs nothing to change before the tool is cut.<\/p>\n<h3>Should I pay for the tool separately?<\/h3>\n<p>Yes, if you can. Separate tool payment gives you a comparable piece price, clear ownership and the ability to move the tool. Amortisation is a financing arrangement, not a discount \u2014 and if it is not documented with an amortisation volume and an end date, you are paying for the tool more than once.<\/p>\n<h3>What is a reasonable reject rate?<\/h3>\n<p>0.5 \u2013 2 % on a part with a normal cosmetic standard, and 3 \u2013 5 % on a part with a strict cosmetic requirement or a difficult material. Anything quoted at zero is either not understood or not committed to.<\/p>\n<h3>Does the machine tonnage matter for price?<\/h3>\n<p>Less than most people think. The hourly rate between a 200 t and a 400 t machine differs by about 40 %, not 100 %. What matters more is running the right shot size \u2014 a small part on a large machine gives long residence time, unstable process and worse quality.<\/p>\n<h3>Can you quote both the tool and the parts?<\/h3>\n<p>Yes, and we quote them separately by default so you can see what each costs. The quotation shows the cavity count, steel type, cycle time, resin grade and the packaging basis, so you can compare it line by line with any other supplier.<\/p>\n<\/div>\n<div class=\"cta\">\n<p class=\"cta-h\">Send the part and the volume \u2014 get a cost breakdown, not just a number<\/p>\n<p>We will show you the cycle time, the cavitation, the resin grade and the material weight behind the price, and tell you which design changes would move it most. A quotation you can actually compare.<\/p>\n<p><a class=\"btn\" href=\"https:\/\/uplastech.com\/fr\/service\/\">Request a cost breakdown<\/a>\n<\/div>\n<div class=\"rel\">\n<h4>Continue reading<\/h4>\n<ul>\n<li><a href=\"https:\/\/uplastech.com\/fr\/injection-molding-design-guidelines\/\">Injection Molding Design Guidelines: 12 Rules That Cut Part Cost<\/a><\/li>\n<li><a href=\"https:\/\/uplastech.com\/fr\/low-volume-injection-molding\/\">Low Volume Injection Molding: When Tooling Pays Off<\/a><\/li>\n<li><a href=\"https:\/\/uplastech.com\/fr\/injection-molding-tolerances\/\">Injection Molding Tolerances: What Is Actually Achievable<\/a><\/li>\n<li><a href=\"https:\/\/uplastech.com\/fr\/injection-molding-material-selection\/\">Injection Molding Material Selection: 14 Plastics Compared<\/a><\/li>\n<li><a href=\"https:\/\/uplastech.com\/fr\/custom-injection-molding-guide\/\">Custom Injection Molding Guide: Process, Cost and Tolerances<\/a><\/li>\n<\/ul>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>How a moulded part price is calculated: machine rate, cycle time, cavitation, material and runner loss, scrap, labour and tooling, with three worked examples.<\/p>","protected":false},"author":1,"featured_media":7510,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"Injection Molding Cost per Part: How Price Is Built","_seopress_titles_desc":"How a moulded part price is calculated: machine rate, cycle time, cavitation, material and runner loss, scrap, labour and tooling, with three worked examples.","_seopress_robots_index":"1","_seopress_robots_follow":"1","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"35","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"https:\/\/uplastech.com\/injection-molding-cost-per-part\/","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"injection molding cost per part","footnotes":""},"categories":[35],"tags":[],"class_list":["post-7518","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-injection-molding"],"meta_box":{"post-to-quiz_to":[]},"_links":{"self":[{"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/posts\/7518","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/comments?post=7518"}],"version-history":[{"count":1,"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/posts\/7518\/revisions"}],"predecessor-version":[{"id":7523,"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/posts\/7518\/revisions\/7523"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/media\/7510"}],"wp:attachment":[{"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/media?parent=7518"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/categories?post=7518"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/uplastech.com\/fr\/wp-json\/wp\/v2\/tags?post=7518"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}