At RiLong, we don\u2019t just mold silicone. We overmold it onto metal inserts \u2014 often for customers who have already been burned by delamination, shifting inserts, or invisible rejects.<\/p>\n\n\n\n
Below are five practical lessons we\u2019ve learned the hard way. If you\u2019re sourcing metal insert overmolding with silicone<\/strong>, these are the questions you should ask any supplier.<\/p>\n\n\n\n Silicone does not stick to a smooth, oily, or glossy metal surface.<\/p>\n\n\n\n \u2705 We do:<\/strong> \u274c\u00a0We avoid:<\/strong> We use industrial\u2011grade primers (Chemlok, Mega, Thixon) applied in a very thin, uniform layer.<\/p>\n\n\n\n \u2705 The right way:<\/strong> \u274c\u00a0The wrong way:<\/strong> Cold metal sucks heat out of the silicone during curing, resulting in weak silicone\u2011to\u2011metal bonding<\/strong>.<\/p>\n\n\n\n \u2705 We preheat inserts<\/strong> to near mold temperature (150\u2013180\u00b0C) and fix them with mold pins or pockets.<\/p>\n\n\n\n \u274c\u00a0Common failure:<\/strong> Thin metal sections heat up fast; thick sections act as a heat sink.<\/p>\n\n\n\n \u2705 We use real\u2011time cavity temperature probes<\/strong> and adjust time\/pressure per design. \u274c\u00a0What we never do:<\/strong> Many adhesion problems are designed in \u2014 sharp edges, uneven wall thickness, or inaccessible areas for primer.<\/p>\n\n\n\n \u2705 We offer DFM (Design for Manufacturing)<\/strong> feedback before tooling starts.<\/p>\n\n\n\n One small change in the metal part geometry can double\u00a0silicone\u2011to\u2011metal bonding<\/strong>\u00a0strength without increasing cost.<\/p>\n\n\n\n We\u2019ve paid the tuition. Now we deliver the results.<\/p>\n\n\n\n Interested in a technical discussion?<\/strong> At RiLong, we don\u2019t just mold silicone. We overmold it onto metal inserts \u2014 often for customers who have already been burned by delamination, shifting inserts, or invisible rejects. Below are five practical lessons we\u2019ve learned the hard way. If you\u2019re sourcing metal insert overmolding with silicone, these are the questions you should ask any supplier. […]<\/p>\n","protected":false},"author":7,"featured_media":7760,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_gspb_post_css":"","kk_blocks_editor_width":"","_kiokenblocks_attr":"","_kiokenblocks_dimensions":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-7759","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/posts\/7759","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/comments?post=7759"}],"version-history":[{"count":2,"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/posts\/7759\/revisions"}],"predecessor-version":[{"id":7762,"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/posts\/7759\/revisions\/7762"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/media\/7760"}],"wp:attachment":[{"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/media?parent=7759"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/categories?post=7759"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rilong-mold.com\/ar\/wp-json\/wp\/v2\/tags?post=7759"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\n\n\n1. The metal surface must be rough \u2014 but also perfectly clean<\/h2>\n\n\n\n
Shot blasting or chemical etching to create a micro\u2011rough anchor pattern.<\/p>\n\n\n\n
Touching the prepared surface with bare fingers. Grease from skin kills\u00a0silicone\u2011to\u2011metal bonding<\/strong>\u00a0instantly.<\/p>\n\n\n\n<\/blockquote>\n\n\n\n
\n\n\n\n2. Primer is not optional \u2014 and too much is as bad as none<\/h2>\n\n\n\n
0.5\u20132 \u00b5m coating thickness, fully dried before loading into the mold.<\/p>\n\n\n\n
Thick, uneven primer, or rushing to mold before the solvent has evaporated.<\/p>\n\n\n\n<\/blockquote>\n\n\n\n
\n\n\n\n3. Metal inserts must be preheated and precisely positioned<\/h2>\n\n\n\n
Insert moves during clamping \u2192 silicone flows where it shouldn\u2019t \u2192 scrap.<\/p>\n\n\n\n<\/blockquote>\n\n\n\n
\n\n\n\n4. Cure parameters are not \u201cone size fits all\u201d<\/h2>\n\n\n\n
We also run destructive peel tests on every new batch \u2014 not just a visual check.<\/p>\n\n\n\n
Set the timer once and hope for the best.<\/p>\n\n\n\n<\/blockquote>\n\n\n\n
\n\n\n\n5. The best advice: involve us before you freeze the design<\/h2>\n\n\n\n
<\/blockquote>\n\n\n\n
\n\n\n\n
Metal insert overmolding with silicone<\/strong> is not \u201cjust pressing rubber against steel\u201d.
It takes controlled roughness, precise chemistry, thermal discipline, and real\u2011shop experience.<\/p>\n\n\n\n
Contact Rilong at sales1@rilong-mold.com or sherry@rilong-mold.com for more detail ideas and solutions.<\/p>","protected":false},"excerpt":{"rendered":"