Timeline for What plastic material is best for a snap-fit design?
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
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| Oct 18, 2019 at 11:44 | comment | added | Jonathan R Swift | In short, pick your material first, based on other design constraints, and then come back with the specifics of your snap fit design if you would like help sizing it such that it will not fail in your chosen material. | |
| Oct 18, 2019 at 11:43 | comment | added | Jonathan R Swift | So far we have: Plastic part to metal, needs to be removable. How big is it? Only one hook or multiple? What force to attach? What force to remove? Can you manually release the clips? Injection Moulded or machined? Does removal need to be one-handed? Does removal need to be child-proof? Are we talking 'repeated removal' in the range of 100x over the product life or 100,000x? How critical is Cost? Do you have a target unit price? How many of these will be manufactured? 10? 10 million? There are so, *so* many factors that will affect material choice beyond "which is best for the snap fit". | |
| Oct 18, 2019 at 11:39 | comment | added | Jonathan R Swift | Whether a particular material is "the best" depends on way more than the allowable strain, though - materials with a high allowable strain will flex without failure, but may be stiff enough to provide the reaction force that you need to hold your clip closed. Please can you add specifics to your question regarding the design constraints. | |
| Oct 18, 2019 at 11:36 | comment | added | Jonathan R Swift | The confusion that you have with the table, is that some values have been tested directly, and others have been inferred from tensile data. For Acetal, the allowable strain in a snap fit application is 7%. For PEI, the Tensile Yield Strain is 14%, so they have inferred that 70% of this value i.e. 9.8% is acceptable for a snap-fit application. | |
| Oct 18, 2019 at 9:36 | answer | added | am304 | timeline score: 3 | |
| Oct 17, 2019 at 23:33 | history | edited | Davbog | CC BY-SA 4.0 |
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| Oct 17, 2019 at 23:20 | history | edited | Davbog | CC BY-SA 4.0 |
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| Oct 17, 2019 at 21:34 | comment | added | Jonathan R Swift | web.mit.edu/2.75/resources/random/… | |
| Oct 17, 2019 at 21:33 | comment | added | Jonathan R Swift | Whether the plastic is permanently deformed is more a function of the hook design than the material itself. There are design guides freely available from the major plastic manufacturers- have a look there first | |
| Oct 17, 2019 at 21:17 | history | asked | Davbog | CC BY-SA 4.0 |