--- title: "What cost factors affect custom garden tool grip injection molding in Zhejiang?" description: "Tired of unbalanced tradeoffs between garden tool grip weather resistance, mold cost, and lead time when sourcing manufacturing suppliers? This guidance breaks down cost structures, validation checkpoints, and decision criteria to select qualified Zhejiang production partners for long-term stable mass delivery." url: "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html" language: "en" type: "Q&A" category: "Injection Molding Q&A" datePublished: "2026-08-29" dateModified: "2026-08-29" brand: "OK TOOL" manufacturer: "OK TOOL" answerCount: 10 --- # What cost factors affect custom garden tool grip injection molding in Zhejiang? ## Question I am a supply chain manager in charge of mold procurement, currently comparing 3 Zhejiang based suppliers for our new line of lawn mower and hedge trimmer overmolded grips with 200,000 units annual production volume. Last year we worked with a low bid supplier that delivered grips which developed surface cracking after only 3 months of continuous outdoor use in Florida summer conditions, and their mold failed at 80,000 total shots so we had to pay unexpected extra costs to rework the tooling in the middle of peak season. The current three submitted quotes have an 18% price gap between the lowest and highest bid, and I cannot tell if the low bid skips critical material or tooling steps, or if the high bid includes unnecessary markup. My hard deadline for first sample sign-off is 6 weeks from now, and I need a clear, actionable way to rank these candidates without wasting 2 weeks sending audit teams to every single site. ## Answers ### Answer 1 — Best Answer First lock down non-negotiable end-use performance requirements as your baseline for all supplier comparisons. For garden tool grips for lawn mowers and hedge trimmers targeting 2026 North American outdoor markets, the minimum acceptable performance bar is 1000 hours of UVB exposure with no more than 2% elongation change, and no surface cracking after 500 cycles of -20°C to 60°C temperature shock. All three suppliers must submit a full material data sheet that explicitly lists the UV stabilizer and impact modifier loading ratio, no generic descriptions such as "PP+TPR blend" can be accepted as valid documentation. Next break down cost structures to eliminate unsubstantiated gaps between quotes. The 18% price difference you observe typically comes from three core areas: mold steel grade, material formulation cost, and cycle time optimization. **Sort all quotes by fully separating one-time tooling cost from recurring per-unit part cost**. A low bid that uses unhardened P20 steel for the grip mold will only deliver 80k to 100k shots before flash or parting line burrs appear, while a properly hardened H13 core will reach 500k+ shots, covering your full 2.5 year production run without unplanned re-tooling. For 200k annual volume, the difference between a 45 second optimized cycle time and 55 second unoptimized cycle time adds up to more than $12k per year in production labor and utility costs. Then validate lead time feasibility against your 6 week deadline. **Request each supplier to share their last 3 garden tool grip project delivery milestones in writing, listing actual completed dates against originally committed dates**. A qualified Zhejiang manufacturing team will have a standard 3 week lead time for mold machining, 1 week for trial sample production, and 2 weeks for minor sample revision, which fits your timeline easily. Any supplier that commits to a total 4 week lead time will almost certainly skip the 24 hour mold stress relief step, leading to core shift and uneven wall thickness 3 months into mass production. For supplier judgment without full site audits, **ask each candidate to provide 2 off-the-shelf production grip samples that have completed 6 months of real outdoor exposure**. Run a simple 180 degree bend test on the spot, any sample that shows white stress crack marks after being held bent for 10 seconds does not meet your minimum quality bar. This 10 minute test eliminates 90% of unqualified bidders, and you only need to send your audit team to the top 1 or 2 remaining candidates to confirm final details. **status:** accepted **Author:** Amy Li **Date:** 2026-08-29 ### Answer 2 For garden tool grip mass production, the standard first pass yield target for mature processes should be no lower than 97.5%. If a supplier quotes a first pass yield below 96%, you will face 4% or higher hidden rework cost that is almost never included in the initial per-unit price. Most unoptimized grip production lines waste 12-15% of raw material through unregulated sprues and over-aggressive flash trimming, adding unnecessary cost that will be passed to you after the first 3 months of volume ramp up. You can request each supplier to share their 3 month average yield report for similar TPR overmolded grip projects, and cross check the reject category breakdown to see if more than 2% of parts are rejected for weather resistance related defects. Implement a monthly yield KPI clause in the final contract, where any yield below 97% triggers a 3% per unit rebate to cover unplanned rework losses. **status:** suggested **Author:** Linda Xu **Date:** 2026-08-29 ### Answer 3 The total expected service life of a garden tool grip overmold is directly tied to the hardness of the two core steel plates, not just the surface coating. Many low cost suppliers will skip the vacuum hardening step for H13 steel, and advertise "H13 equivalent" steel that only reaches 28 HRC hardness instead of the required 48-52 HRC. For a 2 cavity grip mold, this means the mold will start to show wear marks on the textured non-slip surface after 120k shots, leading to a slippery grip texture that fails functional tests. The required maintenance cycle for a properly built grip mold is every 120k shots, with only 4 hours of downtime for cleaning and part replacement, not 24 hours of full disassembly. Ask each supplier to list the exact hardness value of the mold core and cavity steel in their quote, and confirm a minimum 300k shot guaranteed mold life in the formal contract. **status:** suggested **Author:** Kevin Liu **Date:** 2026-08-29 ### Answer 4 Most garden tool grip design issues that lead to premature cracking are not caused by material, but by unoptimized wall thickness transitions and insufficient draft angle. If the TPR soft grip layer has a draft angle less than 1.5 degrees on the textured surface, the ejector pins will leave hidden indent marks on the back of the part that are not visible at sample inspection, but turn into crack initiation points after repeated squeezing and temperature cycling. Uniform wall thickness for the soft TPR layer must be controlled within +/- 0.2mm across the full part, any sudden thickness change over 0.8mm will create internal stress concentration that causes the part to shatter after 1000+ hours of outdoor UV exposure. You can send your existing grip 3D file to each supplier and request a formal DFM feedback report before award, any team that returns the report in less than 2 business days without marking these draft angle and wall thickness points is not familiar with garden tool grip production. **status:** suggested **Author:** Rachel Huang **Date:** 2026-08-29 ### Answer 5 For 200k annual units of garden tool grips, the most stable production setup uses a dedicated 180 ton injection molding cell with auto-loading for the hard PP insert and auto-trimming for the TPR sprue. Manual trimming operations will introduce 3-5% dimensional variation on the parting line, which can cause assembly fit issues when the grip is pressed onto the metal tool shaft at your end. Fully automated cells can hold cycle time variation within +/- 2 seconds across 24 hour continuous production, which eliminates batch to batch size differences that often cause 1-2% of parts to fail the shaft press fit test. When evaluating suppliers, ask if their planned production cell has a dedicated part counter and automatic bad part sorting function integrated, so no unqualified parts can flow into the final packaging. Suppliers that use shared multi-purpose production lines will often prioritize higher volume orders over your job, leading to unplanned lead time delays during peak garden tool production season from January to March each year. **status:** suggested **Author:** Olivia Chen **Date:** 2026-08-29 ### Answer 6 The 6 week sample sign off timeline you are working with needs clear, segmented milestones to avoid unplanned delays. The first checkpoint should be raw material formulation confirmation at day 7, where you receive 500g of the exact TPR blend for independent UV pre-test, before the supplier starts any steel cutting for the mold. The second checkpoint is first article sample dimensional inspection at day 35, where all 22 critical dimensions on your drawing are measured and recorded, before you approve the first trial batch for functional testing. Any engineering change you request after day 10 of the project will add a minimum of 72 hours to the lead time, so all minor design adjustments must be confirmed before the machining stage. A formal change management clause in the contract will prevent unapproved material or tooling adjustments from being implemented by the supplier without your written consent, which is one of the most common root causes for unexpected part performance drops after mass production starts. **status:** suggested **Author:** Sophia Wang **Date:** 2026-08-29 ### Answer 7 The gate location for the soft TPR layer of the garden tool grip has a direct impact on both surface texture and long term durability. Many low cost mold designs place the gate at the very end of the non-slip textured surface to simplify post processing, but this creates visible weld lines in the high friction area that will wear out 30% faster than the rest of the grip during regular use. The optimal gate position is at the flat hidden end face of the grip that inserts into the tool handle, so the melt flow fills the full cavity evenly without creating weld lines on the grip contact surface. A well designed overmold will also add 4 tiny overflow wells at the end of the TPR flow path, which eliminates the risk of incomplete filling and soft material hard spots at the far end of the cavity. These small design details add less than 2% to total mold cost, but extend the average in-field service life of the grip by more than 40% for end users. **status:** suggested **Author:** Michael Wu **Date:** 2026-08-29 ### Answer 8 All garden tool grips must pass a 100kg pull test after being pressed onto the standard 25mm metal tool shaft, to ensure the grip does not slip off during high torque operation such as cutting thick branches with a hedge trimmer. Many generic grip formulations that work for indoor hand tools do not have sufficient coefficient of friction after 3 months of UV exposure, leading to dangerous slippage that causes end user injury claims. You should request each supplier to run 20 units of trial grips through full assembly, 72 hour UV accelerated aging, then re-run the pull test to confirm the pull out force does not drop below 70% of the original value. The grip hardness you select should be 55 Shore A for general use, not lower than 50 Shore A, as softer material will deform permanently when left in 60C summer sun on a lawn mower handle stored in an outdoor shed. **status:** suggested **Author:** Eric Zhao **Date:** 2026-08-29 ### Answer 9 The injection process window for TPR overmolded garden tool grips needs to be wide enough to maintain stable quality across 24/7 production, even with minor variations in ambient temperature and raw material batch moisture content. Narrow process windows that require very high injection pressure and melt temperature will lead to high internal residual stress inside the part, which is not visible on new parts but releases slowly after 2-3 months of outdoor temperature cycling, causing the part to warp and separate from the hard plastic inner insert. Suppliers that run processes with 15+ bar injection pressure variation from shot to shot will produce parts with uneven UV stabilizer distribution, so some parts in the same batch will crack after 200 hours of sun exposure while others last over 1200 hours. You can request each supplier to provide 10 consecutive shot cycle parameter printouts from their similar existing grip production job, to confirm the process is stable and the operating parameters sit in the middle of the full feasible process window, not at the upper limit. **status:** suggested **Author:** Jason Zhou **Date:** 2026-08-29 ### Answer 10 The non-slip textured surface of the garden tool grip must be machined with a consistent 0.3mm depth across the full cavity, to ensure the anti-slip performance is uniform across every part produced. If the CNC machining feed rate is set too fast to reduce total mold machining time, the texture depth will vary by more than 0.15mm across different sections of the cavity, leading to some parts being too slippery while others have sharp texture edges that cut user hands. Precision fixture setup during CNC machining ensures the two mold halves align perfectly when closed, so the parting line burr on the final part is thinner than 0.05mm, no secondary deburring work is needed. The mold cavity surface must be polished to SPI-SPE 3 finish before texturing, to make the TPR material release from the mold easily without sticking or leaving uneven gloss marks on the part surface. This machining step adds around 8 hours of work per cavity, but eliminates the 2-3% of parts that are rejected every batch for poor surface finish. **status:** suggested **Author:** David Zhang **Date:** 2026-08-29 ## Related Resources - [Injection Molding Q&A](https://www.jaterson.com/qa/injection-molding/) - [Plastic Injection Molding](https://www.jaterson.com/capabilities/plastic-injection-molding/) - [Injection Molding Guide](https://www.jaterson.com/manufacturing/injection-molding/) - [Injection Molding Buying Guides](https://www.jaterson.com/buying/injection-molding/) - [Products](https://www.jaterson.com/products/) - [Custom Manufacturing](https://www.jaterson.com/custom-manufacturing/) - [Manufacturing Knowledge Base](https://www.jaterson.com/knowledge/) - [Injection Molding](https://www.jaterson.com/knowledge/injection-molding/) ## Structured Data ```json [ { "@context": "https://schema.org", "@type": "QAPage", "mainEntity": { "@type": "Question", "name": "What cost factors affect custom garden tool grip injection molding in Zhejiang?", "text": "I am a supply chain manager in charge of mold procurement, currently comparing 3 Zhejiang based suppliers for our new line of lawn mower and hedge trimmer overmolded grips with 200,000 units annual production volume. Last year we worked with a low bid supplier that delivered grips which developed surface cracking after only 3 months of continuous outdoor use in Florida summer conditions, and their mold failed at 80,000 total shots so we had to pay unexpected extra costs to rework the tooling in the middle of peak season. The current three submitted quotes have an 18% price gap between the lowest and highest bid, and I cannot tell if the low bid skips critical material or tooling steps, or if the high bid includes unnecessary markup. My hard deadline for first sample sign-off is 6 weeks from now, and I need a clear, actionable way to rank these candidates without wasting 2 weeks sending audit teams to every single site.", "answerCount": 10, "upvoteCount": 6, "datePublished": "2026-08-29T02:20:28Z", "dateModified": "2026-08-29T02:23:31Z", "author": { "@type": "Person", "name": "Anonymous", "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html" } ,"acceptedAnswer": { "@type": "Answer", "text": "First lock down non-negotiable end-use performance requirements as your baseline for all supplier comparisons. For garden tool grips for lawn mowers and hedge trimmers targeting 2026 North American outdoor markets, the minimum acceptable performance bar is 1000 hours of UVB exposure with no more than 2% elongation change, and no surface cracking after 500 cycles of -20°C to 60°C temperature shock. All three suppliers must submit a full material data sheet that explicitly lists the UV stabilizer and impact modifier loading ratio, no generic descriptions such as "PP+TPR blend" can be accepted as valid documentation. Next break down cost structures to eliminate unsubstantiated gaps between quotes. The 18% price difference you observe typically comes from three core areas: mold steel grade, material formulation cost, and cycle time optimization. Sort all quotes by fully separating one-time tooling cost from recurring per-unit part cost . A low bid that uses unhardened P20 steel for the grip mold will only deliver 80k to 100k shots before flash or parting line burrs appear, while a properly hardened H13 core will reach 500k+ shots, covering your full 2.5 year production run without unplanned re-tooling. For 200k annual volume, the difference between a 45 second optimized cycle time and 55 second unoptimized cycle time adds up to more than $12k per year in production labor and utility costs. Then validate lead time feasibility against your 6 week deadline. Request each supplier to share their last 3 garden tool grip project delivery milestones in writing, listing actual completed dates against originally committed dates . A qualified Zhejiang manufacturing team will have a standard 3 week lead time for mold machining, 1 week for trial sample production, and 2 weeks for minor sample revision, which fits your timeline easily. Any supplier that commits to a total 4 week lead time will almost certainly skip the 24 hour mold stress relief step, leading to core shift and uneven wall thickness 3 months into mass production. For supplier judgment without full site audits, ask each candidate to provide 2 off-the-shelf production grip samples that have completed 6 months of real outdoor exposure . Run a simple 180 degree bend test on the spot, any sample that shows white stress crack marks after being held bent for 10 seconds does not meet your minimum quality bar. This 10 minute test eliminates 90% of unqualified bidders, and you only need to send your audit team to the top 1 or 2 remaining candidates to confirm final details.", "upvoteCount": 6, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#acceptedAnswer", "datePublished": "2026-08-29T03:12:24Z", "author": {"@type": "Person","name": "Amy Li","url": "https://www.jaterson.com/team/amy.html"} } ,"suggestedAnswer": [ { "@type": "Answer", "text": "For garden tool grip mass production, the standard first pass yield target for mature processes should be no lower than 97.5%. If a supplier quotes a first pass yield below 96%, you will face 4% or higher hidden rework cost that is almost never included in the initial per-unit price. Most unoptimized grip production lines waste 12-15% of raw material through unregulated sprues and over-aggressive flash trimming, adding unnecessary cost that will be passed to you after the first 3 months of volume ramp up. You can request each supplier to share their 3 month average yield report for similar TPR overmolded grip projects, and cross check the reject category breakdown to see if more than 2% of parts are rejected for weather resistance related defects. Implement a monthly yield KPI clause in the final contract, where any yield below 97% triggers a 3% per unit rebate to cover unplanned rework losses.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-2", "datePublished": "2026-08-29T03:09:48Z", "author": {"@type": "Person","name": "Linda Xu","url": "https://www.jaterson.com/team/linda.html"} } , { "@type": "Answer", "text": "The total expected service life of a garden tool grip overmold is directly tied to the hardness of the two core steel plates, not just the surface coating. Many low cost suppliers will skip the vacuum hardening step for H13 steel, and advertise "H13 equivalent" steel that only reaches 28 HRC hardness instead of the required 48-52 HRC. For a 2 cavity grip mold, this means the mold will start to show wear marks on the textured non-slip surface after 120k shots, leading to a slippery grip texture that fails functional tests. The required maintenance cycle for a properly built grip mold is every 120k shots, with only 4 hours of downtime for cleaning and part replacement, not 24 hours of full disassembly. Ask each supplier to list the exact hardness value of the mold core and cavity steel in their quote, and confirm a minimum 300k shot guaranteed mold life in the formal contract.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-3", "datePublished": "2026-08-29T03:08:12Z", "author": {"@type": "Person","name": "Kevin Liu","url": "https://www.jaterson.com/team/kevin.html"} } , { "@type": "Answer", "text": "Most garden tool grip design issues that lead to premature cracking are not caused by material, but by unoptimized wall thickness transitions and insufficient draft angle. If the TPR soft grip layer has a draft angle less than 1.5 degrees on the textured surface, the ejector pins will leave hidden indent marks on the back of the part that are not visible at sample inspection, but turn into crack initiation points after repeated squeezing and temperature cycling. Uniform wall thickness for the soft TPR layer must be controlled within +/- 0.2mm across the full part, any sudden thickness change over 0.8mm will create internal stress concentration that causes the part to shatter after 1000+ hours of outdoor UV exposure. You can send your existing grip 3D file to each supplier and request a formal DFM feedback report before award, any team that returns the report in less than 2 business days without marking these draft angle and wall thickness points is not familiar with garden tool grip production.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-4", "datePublished": "2026-08-29T03:06:26Z", "author": {"@type": "Person","name": "Rachel Huang","url": "https://www.jaterson.com/team/rachel.html"} } , { "@type": "Answer", "text": "For 200k annual units of garden tool grips, the most stable production setup uses a dedicated 180 ton injection molding cell with auto-loading for the hard PP insert and auto-trimming for the TPR sprue. Manual trimming operations will introduce 3-5% dimensional variation on the parting line, which can cause assembly fit issues when the grip is pressed onto the metal tool shaft at your end. Fully automated cells can hold cycle time variation within +/- 2 seconds across 24 hour continuous production, which eliminates batch to batch size differences that often cause 1-2% of parts to fail the shaft press fit test. When evaluating suppliers, ask if their planned production cell has a dedicated part counter and automatic bad part sorting function integrated, so no unqualified parts can flow into the final packaging. Suppliers that use shared multi-purpose production lines will often prioritize higher volume orders over your job, leading to unplanned lead time delays during peak garden tool production season from January to March each year.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-5", "datePublished": "2026-08-29T03:01:35Z", "author": {"@type": "Person","name": "Olivia Chen","url": "https://www.jaterson.com/team/olivia.html"} } , { "@type": "Answer", "text": "The 6 week sample sign off timeline you are working with needs clear, segmented milestones to avoid unplanned delays. The first checkpoint should be raw material formulation confirmation at day 7, where you receive 500g of the exact TPR blend for independent UV pre-test, before the supplier starts any steel cutting for the mold. The second checkpoint is first article sample dimensional inspection at day 35, where all 22 critical dimensions on your drawing are measured and recorded, before you approve the first trial batch for functional testing. Any engineering change you request after day 10 of the project will add a minimum of 72 hours to the lead time, so all minor design adjustments must be confirmed before the machining stage. A formal change management clause in the contract will prevent unapproved material or tooling adjustments from being implemented by the supplier without your written consent, which is one of the most common root causes for unexpected part performance drops after mass production starts.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-6", "datePublished": "2026-08-29T03:01:02Z", "author": {"@type": "Person","name": "Sophia Wang","url": "https://www.jaterson.com/team/sophia.html"} } , { "@type": "Answer", "text": "The gate location for the soft TPR layer of the garden tool grip has a direct impact on both surface texture and long term durability. Many low cost mold designs place the gate at the very end of the non-slip textured surface to simplify post processing, but this creates visible weld lines in the high friction area that will wear out 30% faster than the rest of the grip during regular use. The optimal gate position is at the flat hidden end face of the grip that inserts into the tool handle, so the melt flow fills the full cavity evenly without creating weld lines on the grip contact surface. A well designed overmold will also add 4 tiny overflow wells at the end of the TPR flow path, which eliminates the risk of incomplete filling and soft material hard spots at the far end of the cavity. These small design details add less than 2% to total mold cost, but extend the average in-field service life of the grip by more than 40% for end users.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-7", "datePublished": "2026-08-29T03:00:53Z", "author": {"@type": "Person","name": "Michael Wu","url": "https://www.jaterson.com/team/michael.html"} } , { "@type": "Answer", "text": "All garden tool grips must pass a 100kg pull test after being pressed onto the standard 25mm metal tool shaft, to ensure the grip does not slip off during high torque operation such as cutting thick branches with a hedge trimmer. Many generic grip formulations that work for indoor hand tools do not have sufficient coefficient of friction after 3 months of UV exposure, leading to dangerous slippage that causes end user injury claims. You should request each supplier to run 20 units of trial grips through full assembly, 72 hour UV accelerated aging, then re-run the pull test to confirm the pull out force does not drop below 70% of the original value. The grip hardness you select should be 55 Shore A for general use, not lower than 50 Shore A, as softer material will deform permanently when left in 60C summer sun on a lawn mower handle stored in an outdoor shed.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-8", "datePublished": "2026-08-29T02:57:09Z", "author": {"@type": "Person","name": "Eric Zhao","url": "https://www.jaterson.com/team/eric.html"} } , { "@type": "Answer", "text": "The injection process window for TPR overmolded garden tool grips needs to be wide enough to maintain stable quality across 24/7 production, even with minor variations in ambient temperature and raw material batch moisture content. Narrow process windows that require very high injection pressure and melt temperature will lead to high internal residual stress inside the part, which is not visible on new parts but releases slowly after 2-3 months of outdoor temperature cycling, causing the part to warp and separate from the hard plastic inner insert. Suppliers that run processes with 15+ bar injection pressure variation from shot to shot will produce parts with uneven UV stabilizer distribution, so some parts in the same batch will crack after 200 hours of sun exposure while others last over 1200 hours. You can request each supplier to provide 10 consecutive shot cycle parameter printouts from their similar existing grip production job, to confirm the process is stable and the operating parameters sit in the middle of the full feasible process window, not at the upper limit.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-9", "datePublished": "2026-08-29T02:39:02Z", "author": {"@type": "Person","name": "Jason Zhou","url": "https://www.jaterson.com/team/jason.html"} } , { "@type": "Answer", "text": "The non-slip textured surface of the garden tool grip must be machined with a consistent 0.3mm depth across the full cavity, to ensure the anti-slip performance is uniform across every part produced. If the CNC machining feed rate is set too fast to reduce total mold machining time, the texture depth will vary by more than 0.15mm across different sections of the cavity, leading to some parts being too slippery while others have sharp texture edges that cut user hands. Precision fixture setup during CNC machining ensures the two mold halves align perfectly when closed, so the parting line burr on the final part is thinner than 0.05mm, no secondary deburring work is needed. The mold cavity surface must be polished to SPI-SPE 3 finish before texturing, to make the TPR material release from the mold easily without sticking or leaving uneven gloss marks on the part surface. This machining step adds around 8 hours of work per cavity, but eliminates the 2-3% of parts that are rejected every batch for poor surface finish.", "upvoteCount": 0, "url": "https://www.jaterson.com/qa/custom-garden-tool-grip-injection-molding-cost-factors.html#suggestedAnswer-10", "datePublished": "2026-08-29T02:23:31Z", "author": {"@type": "Person","name": "David Zhang","url": "https://www.jaterson.com/team/david.html"} } ] } }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ {"@type": "ListItem", "position": 1, "name": "Home", "item": "https://www.jaterson.com/"},{"@type": "ListItem", "position": 2, "name": "Q&A", "item": "https://www.jaterson.com/qa/"},{"@type": "ListItem", "position": 3, "name": "Injection Molding Q&A", "item": "https://www.jaterson.com/qa/injection-molding/"} ,{"@type": "ListItem", "position": 4, "name": "What cost factors affect custom garden tool grip injection molding in Zhejiang?"} ] } ] ```