This is a project I’ve been working on for the past two weeks. Hardtop season brings about the annual worry about keeping the top secure. This usually brings about the annual googling for security hardware. This year, I found something very interesting...
These nuts are usually used to secure signs to poles. Once one of these is installed, signs stop being stolen. And they happened to be sold in metric sizes. WOO! I bought a couple hundred on a whim.
The back side.
These things are big.
I worked for a couple of weeks trying to come up with a universal mounting solution that anyone could use with any Spec hardtop plate and any rollbar. I left the garage angry every evening. After two weeks, I decided there just was no single solution. People will have to figure out how to install these in their own cars themselves. Some will need short studs. Others will need long ones. Some will only be able to use the hardware on the windshield area, others will only be able to use it on the side latch area.
These nuts are huge. Installing them sucks. But it will probably suck less than having your hardtop stolen.
You will need to source your own mounting studs. Here in the States, ACE Hardware has a fine selection. For the windshield, I used 40mm studs and was able to get things to bolt down. For the side latches, I could just barely get 30mm studs to clear my rollbar.
All of the hardtop-side hardware is M6x1.0 threaded.
All of the body-side hardware is M8x1.25 threaded. There is one exception: the fastener on the side latch area that has the nipple to attach the boot. That one is an M6 bolt.
How to Install
The nut is flat against the plate. This is good.
The nut is not flat. A tool could get under it. This is bad.
If you install the security hardware so that it’s flat against the backing plate, you’ll have a secure installation. It is nearly impossible to get any tool over top to remove it. But if you have a plate that’s not quite perpendicular to the plane that the mounting hardware uses, you open up the opportunity for a tool to slide under and your security nut to be compromised.
If you add RED LOCTITE to the security nut, you create a lock that is impossible to remove without adding heat. Let me repeat. Add Red Loctite and you will have a very secure hardtop installation. You will have to heat up the hardware with a torch to remove the top.
And how do you install these nuts anyway?
That’s right. The nut is its own locking tool. You install a second nut over top of the first and back it off 3/4 of a turn. Then you tighten the combo with an adjustable wrench 1/4 turn at a time. You can install these square security nuts as tight as you like. That’s a feature that not all security hardware shares.
What you get.
You get five (5) of each size security nut, both M6 and M8. That is enough to put one on each side of a Spec Miata hardtop plate system, plus one nut of each size to act as a lock.
You get a sticker! (Perhaps two)
You get a random Domo-Kun! (maybe two!)
You get free shipping! (in the continental US only)
All this for $18 USD.
You can either fill out the order form on my store site (pick Some other product from the dropbox) or you can email me: adam at revlimiter dot net.
OR you can just send me a paypal for the $18 if you really want. My paypal address is revlimiter@gmail.com
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Originally Posted by The Platypus
