{"id":565,"date":"2026-10-15T11:52:26","date_gmt":"2026-10-15T03:52:26","guid":{"rendered":"http:\/\/www.allfirepump.com\/blog\/?p=565"},"modified":"2026-10-15T11:52:26","modified_gmt":"2026-10-15T03:52:26","slug":"do-plastic-gears-have-good-resistance-to-uv-radiation-48ac-ad4073","status":"publish","type":"post","link":"http:\/\/www.allfirepump.com\/blog\/2026\/10\/15\/do-plastic-gears-have-good-resistance-to-uv-radiation-48ac-ad4073\/","title":{"rendered":"Do plastic gears have good resistance to UV radiation?"},"content":{"rendered":"

Hey there, if you\u2019ve ever spent time scrolling through gear specs or worked on a project that needs durable, lightweight moving parts, you\u2019ve probably wondered: how do plastic gears hold up when exposed to sunlight? I get it\u2014 I\u2019m a plastic gear supplier, so this is the kind of question I get at least once a week, usually from folks building outdoor equipment, garden machinery, solar components, or even playground gear. A lot of people default to metal for UV-heavy setups, but let\u2019s cut through the noise: plastic gears don\u2019t all handle UV the same, and when paired with the right material, they can outlast metal in a ton of outdoor scenarios. Let\u2019s break this down like I would over a coffee with a customer, no boring jargon, just real talk from someone who\u2019s shipped these parts for 15+ years. Plastic Gear<\/a><\/p>\n

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First off, let\u2019s get one thing straight: not all plastics are created equal. That\u2019s the biggest mistake I see buyers make\u2014 they pick the cheapest off-the-shelf nylon gear, assume it\u2019ll work, and then wonder why it cracks after a month sitting outside next to their new patio grill. UV radiation isn\u2019t just sunlight; it\u2019s the part of sunlight that breaks down molecular bonds, right? For plastics, that means the polymer chains start to degrade, the material gets brittle, it fades, and before you know it, your gear\u2019s teeth are chipping or snapping mid-cycle. Metal rusts or corroded, but plastics \u201cweather\u201d differently\u2014 and bad weathering from UV is the number one killer of cheap plastic gears outdoors.<\/p>\n

Now, here\u2019s the good news: we don\u2019t have to guess which plastics handle UV. At my shop, we test every material we use under a UV lamp for 1,000, 2,000, even 5,000 hours before we\u2019ll put it on a shelf. The workhorses for UV-resistant plastic gears? Let\u2019s name the ones we sell most, because these are the real MVPs. First up: Nylon 6\/6 with UV stabilizers. Wait, no\u2014 regular nylon is garbage in the sun, but add a UV stabilizer (usually a pigment or an additive that absorbs or reflects UV light) and it\u2019s a different beast. We don\u2019t cut corners here\u2014 we use stabilizers that are specifically formulated for engineering plastics, not just random color dyes. A lot of competitors will throw a black dye in nylon and call it \u201cUV-resistant,\u201d but black dye actually absorbs some UV, it doesn\u2019t stop degradation. Our Nylon 6\/6 with the right stabilizer can hold up to 3,000+ hours of continuous outdoor exposure before its tensile strength drops by even 10%\u2014 that\u2019s way longer than most metal gears in wet, sunny climates like Florida or Arizona.<\/p>\n

Next, even better for super harsh UV? Acetal (also called Delrin, wait\u2014 but not the cheap Delrin knockoffs). Wait, standard acetal is actually pretty bad at UV\u2014 it fades and gets brittle fast. But if you get UV-stabilized acetal, that\u2019s a game-changer. We use a specialty grade of acetal that\u2019s reinforced with carbon fiber and treated with a UV inhibitor that blocks 95% of UVA and UVB rays. These gears are stiffer than nylon, they handle higher loads, and they don\u2019t get brittle even after 5,000 hours of outdoor testing. I had a customer last year who built a solar tracker system\u2014 those gears are sitting out in the desert, 12 hours a day of direct sun, 110\u00b0F temps, and they\u2019ve been running for 18 months with zero issues. He switched from stainless steel gears because the metal ones corroded in the dust and sand, and the plastic ones are lighter, cheaper, and don\u2019t rust. That\u2019s the kind of win we live for.<\/p>\n

Wait, what about the common question: \u201cHow do these compare to metal gears in UV?\u201d Let\u2019s be real\u2014 metal doesn\u2019t \u201cdegrade\u201d from UV the same way, but metal\u2019s enemy when exposed to sun and moisture is corrosion. If you have a gear that\u2019s moving, exposed to rain, humidity, or salt air (like a marina or coastal equipment), a stainless steel gear will rust, pitting happens, and the teeth wear out fast. Plastic gears? As long as they\u2019re the right UV-resistant grade, they don\u2019t corrode, they keep their lubrication longer (wait, right\u2014 most plastic gears are self-lubricating, or we can add a dry lube coating that doesn\u2019t wash off in rain), and they don\u2019t attract dust like metal, which means less wear on the teeth. I\u2019ve seen UV-stabilized plastic gears outlast metal by 2-3 years in coastal applications, no lie.<\/p>\n

But let\u2019s not sugarcoat it: there are limits. The worst thing you can do is use a plastic gear that\u2019s not formulated for UV exposure. I had a customer come to me last year with a broken gear from a kid\u2019s playground swing set. He used a random ABS gear from the hardware store\u2014 ABS is cheap, super easy to mold, but it\u2019s terrible at UV. After 6 months of being out in the sun, the gear got so brittle it snapped when a kid swung on it. That\u2019s a safety issue, so we always tell customers: if your gear is going to be outdoors, near windows, or anywhere it\u2019s exposed to UV for more than a few hours a day, skip the ABS, skip the standard nylon, skip the generic Delrin. Ask for UV-stabilized grades, and if you\u2019re not sure, just shoot us an email\u2014 we\u2019ll tell you straight up if your application needs a specific material.<\/p>\n

Another factor: temperature. Wait, UV and heat go hand in hand, right? If your gear is sitting in 120\u00b0F sun, the UV degradation is way faster than if it\u2019s in a shaded spot. That\u2019s why we also test for thermal stability paired with UV\u2014 some stabilizers break down at high temps, so we use dual-function additives that handle both UV and heat. For example, our UV-stabilized nylon can handle temps up to 180\u00b0F, so it works on a grill\u2019s rotating spit gear or a solar panel tracker, no problem. We\u2019ve had customers use these gears on farm equipment, where they\u2019re exposed to sun, dirt, and varying temps, and they report zero gear failures from UV in over 2 years.<\/p>\n

What about other materials? Polycarbonate? No, that\u2019s for lenses, not gears\u2014 it\u2019s too flexible, and UV breaks it down fast. UHMWPE? Maybe for low-load, non-critical parts, but it\u2019s not stiff enough for most gear applications. The only plastics we recommend for UV-resistant gears are the ones I named earlier: UV-stabilized nylon 6\/6, UV-stabilized acetal, and sometimes glass-filled nylon with UV additives for higher-load setups. We don\u2019t mess around with the cheap stuff that\u2019s going to fail and cost our customers time and money.<\/p>\n

Wait, let\u2019s talk about real-world data, not lab tests. Last quarter, we shipped 200 sets of UV-stabilized acetal gears to a company that makes outdoor power equipment\u2014 lawnmower drive gears, weed whacker gears, all exposed to sun and rain. Their old metal gears were failing every 12 months due to corrosion; our plastic gears have been running for 15 months now, and their failure rate is less than 1%. That\u2019s not a fluke. Another client: a medical device company that makes outdoor patient monitors (wait, yes, they have to be durable for sun exposure, and they can\u2019t have metal parts that might rust and contaminate equipment). They switched from stainless to our UV-stabilized nylon gears, and they passed all their durability tests with flying colors.<\/p>\n

Now, the big question: should you use plastic gears for your UV-exposed application? Let\u2019s answer that. If your gear is low to medium load, moving at moderate speeds, exposed to daily sunlight (even just through a window), and you want something lightweight, corrosion-resistant, and low-maintenance\u2014 ABSOLUTELY. Metal has its place, but for most outdoor or UV-heavy applications, UV-stabilized plastic gears are better, cheaper, and longer-lasting. If your gear is under extremely high load (like heavy industrial equipment, massive conveyors), metal might still be the way to go, but even then, we can sometimes mold high-load UV-stabilized glass-filled nylon gears that hold up.<\/p>\n

A lot of people ask us: \u201cCan you coat plastic gears for more UV resistance?\u201d The short answer is: sometimes, but it\u2019s not necessary if you use the right base material. Coating can add cost, and if the coating scratches or peels, it doesn\u2019t do anything. Our UV additives are mixed into the plastic at the molecular level during manufacturing, so they don\u2019t wash off, don\u2019t scratch off, and work for the entire lifespan of the gear. That\u2019s why our gears outlast coated ones every time\u2014 no extra steps, no extra cost, just material made to handle sun.<\/p>\n

Wait, let\u2019s clear up a common myth: people think plastic gets soft in the sun. Only if it\u2019s the wrong plastic. Our UV-stabilized acetal has a heat deflection temp of over 300\u00b0F, so even in direct midday sun, it won\u2019t soften. The nylon is around 220\u00b0F, which is more than enough for any outdoor application you\u2019ll find. The only time we\u2019ve seen plastic soften is when a customer used a low-quality material that doesn\u2019t have proper heat or UV additives\u2014 that\u2019s not our fault, that\u2019s cutting corners.<\/p>\n

At the end of the day, as a plastic gear supplier, my number one goal isn\u2019t just to sell you a part\u2014 it\u2019s to sell you a part that works. I\u2019d rather tell a customer \u201cdon\u2019t use plastic, use metal\u201d than sell them a gear that breaks in 2 months. But 9 times out of 10, when someone asks about UV resistance, we can point them to a grade of plastic that will outperform metal, save them money on maintenance, and last longer.<\/p>\n

If you\u2019re working on a project, building outdoor equipment, solar components, playground gear, or anything that\u2019s going to see sun, and you\u2019re wondering if plastic gears are right for you\u2014 just reach out. We can send you sample gears, run quick tests, or walk you through the best material for your load, speed, and UV exposure level. No sales pitch, no pressure, just real advice from someone who\u2019s been in this game for years, and knows exactly what works in the sun and what doesn\u2019t.<\/p>\n

<\/p>\n

Don\u2019t guess on gear material\u2014 especially when UV is a factor. A little bit of research or a quick chat with someone who knows plastic gears can save you a ton of time and money on replacements down the line. And hey, if you have a specific application in mind, send us the details\u2014 we\u2019re here to help you pick the perfect gear that\u2019ll hold up even under the harshest sun.<\/p>\n

Automotive Injection Molded Parts<\/a> References<\/p>\n

    \n
  1. Briscoe, B. J., & Sinha, S. (2002). Tribology of polymer composites for gears. Elsevier.<\/li>\n
  2. ASTM G154. Standard Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Nonmetallic Materials. ASTM International.<\/li>\n
  3. Harper, C. A. (2001). Handbook of Plastics, Elastomers, and Composites. McGraw-Hill.<\/li>\n
  4. Ashby, M. F., & Jones, D. R. H. (2005). Engineering Materials 2: An Introduction to Microstructures, Processing and Design. Butterworth-Heinemann.<\/li>\n<\/ol>\n
    \n

    Ningbo Xinyu Automotive Electronics Co., Ltd.<\/a>
    With abundant experience, we are one of the most professional plastic gear manufacturers and suppliers in China. We warmly welcome you to wholesale customized plastic gear from our factory. If you have any enquiry about quotation, please feel free to email us.
    Address: Zhujiadu Village, Sanqizhen, Yuyao City, Zhejiang Province
    E-mail: xyautoelec@163.com
    WebSite:     https:\/\/www.xyautoelec.com\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

    Hey there, if you\u2019ve ever spent time scrolling through gear specs or worked on a project … Do plastic gears have good resistance to UV radiation?<\/span>Read more<\/a><\/p>\n","protected":false},"author":299,"featured_media":565,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[528],"class_list":["post-565","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry","tag-plastic-gear-45a6-ad76e8"],"_links":{"self":[{"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/posts\/565","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/users\/299"}],"replies":[{"embeddable":true,"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/comments?post=565"}],"version-history":[{"count":0,"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/posts\/565\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/posts\/565"}],"wp:attachment":[{"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/media?parent=565"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/categories?post=565"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.allfirepump.com\/blog\/wp-json\/wp\/v2\/tags?post=565"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}