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| 4-40 x 3/8" API 500 Series mounting screws, Click to enlarge |
The screws used to retain 500-series modules in an API 500 series audio rack are 4-40 x 3/8" machine screws with a Phillips oval head, typically in black oxide finish. Some vendors like Behringer use a Star shape driver instead of Phillips — presumably to provide a more secure drive into place.
Regardless, these little mounting screws can easily miss the mark when you’re installing a new module, then they invariably fall inside your rack (you did turn it off didn’t you?) where they can short out the power supply and cause problems if you don’t retrieve them — there must be a better way.
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| Thumb Set screws in Bento 2 rack, click to enlarge |
I found these Radial ThumbSet Screws quite by accident one day and ordered a bag of 12 for $19.99 from Sweetwater. I’ve ordered a few more bags since that first encounter because they work so well. At first I thought they were ripping us off but nothing else on the planet needs these and I’m thankful Radial tooled up and brought them to the market.
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| click to enlarge |
Each screw has a slot so you can use a screwdriver if necessary but I just use my fingers and only tighten them “finger tight”. You might choke — at first — on the price, they are not cheap but they are high quality and I’ve never received a bad one. Each screw comes with a tiny plastic washer to protect the finish on your modules. The threads are not super long but they are long enough to get a couple of turns into the chassis — just don’t torque them down too tight or you might strip a thread, I’ve never had any fail.
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| click to enlarge |
Once you start mounting your 500 series modules using these you’ll want more, they make it easy to install and change 500 series modules at will. The knurled edges make these screws easy to grip, I’ve never dropped one into a rack yet.
EPILOGUE
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| Click to enlarge |
Not much else to say about these, they make life easier and they work well. What’s not to like?
Thanks for reading High on Technology, Good Music To You!
©May 2025 by Mark King, It is not ok to copy or quote without written permission from the author.
Go forth and create something beautiful……..
