1/4-20 Machine Screws for Watseboard

I found some nice 1/4-20 machine screws to secure my wasteboard to my CNC table top. I’m using flanged, threaded inserts installed from the bottom side of the 3/4" MDF table top. While searching for low profile fasteners with a wide head (to help prevent pull through), I found these sidewalk bolts from Hillman on Amazon. They are stainless steel with both a slotted and philips head. Head diameter is right at 0.750" and the head thickness is approximately 0.115. Countersink holes at 0.800" diameter and 0.325 deep worked great with these fasteners. Only $27 for 100 at 1-1/4" long.

Amazon Link


Thanks Joe - welcome to the forums. I used these: https://amzn.to/3aK9OJp - ones you found seem to be a lot less expensive, though I’m not a fan of the philips head. I quick search on the inter webs didn’t turn up any sidewalk or hurricane bolts with anything other than philips or slotted. I will add these to my list though!


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Thanks Tom! Yes, it’s unfortunate they aren’t hex drive like the connector bolts you linked. I did the same search you did for hex drive hurricane/sidewalk bolts and came up with nothing. I did discover after my initial post that a #2 square drive (R2) will work with these bolts. Not a replacement for hex drive, but perhaps a a little less likely to cam out than a phillips driver.

FYI These are made specially for that screw. Search for driver bit for hurricane screws. There are several types.
Screwdriving Bit Adapter https://www.lowes.com/pd/Hillman-3-1-2-in-Screwdriving-Bit-Adapter/4222747