GPS Lock, differently

[whodat]

In my recent GPS mount threads, the issue of security came up. The Zumo 396LMS I use doesn't have any, and I've not seen any commercially available locks for it. Oh well, let's get to making something.

So the 396 has a button on the bottom you press which slides out a piece on the right side that unhooks the GPS. If I could cover the button or stop the moving bit it can't be removed. It was easier to stop the moving bit. On a side note, the 396 has wifi built in so there's really not a good reason it has to come off the bike, ever. You can update it, update the maps, transfer tracks and whatnot without a direct cable connection.

I started by grabbing a whunk of aluminum extrusion I've had laying around for years colored it with a sharpie and laid out some general cut lines.

Untitled by Uncle Grr!, on Flickr

Then I laid into it with the milling machine. Most work was done with an 11/16" two flute end mill because that was my sharpest one.

Untitled by Uncle Grr!, on Flickr

Note that this was made more on kind of a general idea than a plan and was intended to be a proof of concept. If I liked it I'd make a better one.

Many hours of milling and a colossal amount of aluminum chips sprayed everywhere near the mill this is what I ended up with.

Untitled by Uncle Grr!, on Flickr

You can see in this one that I had some pretty sketchy work holding and it let go once, leading to some pretty big divots in the part. Good thing it's on the back side.

Untitled by Uncle Grr!, on Flickr

Installed enough to test.

Untitled by Uncle Grr!, on Flickr

This is a bottom view. The gap between the two parts is exactly how much is needed to remove the GPS.

Untitled by Uncle Grr!, on Flickr

And here it is with a screw installed in the tapped hole. It's tapped M5, and for testing purposes just has a regular shcs installed. I have a box of security torx screws on the way that will be installed.

Untitled by Uncle Grr!, on Flickr

And now we have a quick interlude from Webster's dictionary. Machining is a process of removing material until you get the shape you want. Liken it to carving a boat from a log. Fabricating is a process of adding chunks of material till you get the shape you want. Liken it to building a model.

Because the first mount I made was done possibly the most difficult way possible this side of miracling it out of thin air, I figured I'd see if there was an easier way.

I grabbed one of the spare GPS mounts I made a bit ago and pondered heavily while drinking a beer and scratching my head. Then I went to the scrap pile. My neighbor had given me some shelves that were held up with a bent 1/8" stainless bracket. I cut it apart, bent it to fit, tapped to M5 and welded it to the mount plate.

Untitled by Uncle Grr!, on Flickr

Untitled by Uncle Grr!, on Flickr

End result, exactly the same. Effort required, nearly none comparatively. Sometimes machining is called for, sometimes fabricating is called for. Sometimes it's fun to do both. Both brackets are now in paint, and when they're dry I'll decide which one is going on my bike and the other will go on the shelf as a spare.

I'll update once I get the screws and get it installed.

Edit: I don't know why those last couple pics make it look so crooked. It's not.

[EdMat]

Enjoy your projects, keep em coming..................

[pegasus1300]

I have always been in awe of people who could machine a part out of a block of metal. Thanks for showing us your work. Hope all ends up well.

[Rattlebars]

My solution, maybe not for everyone, is to use $40 GPS units. Garmin 56LM models had on ebay for $50 or less. Audio out? Easy to add. If someone gets it from my RAM cradle which ain't easy, don't care. I have 3 spares. Water proof? Ziploc bag. Mounting? I'm a minimalist. Bent and drilled 14 gauge steel. Routes and added stuff? SD card.

Yours looks factory. Nice work as always.

[samewok]

There is one called cradle lock.i have had it for 5 years

[JayBros]

I agree with Paul; have always thought it would be fun to have a small lathe and milling machine to see what I could come up with to solve problems.

[whodat]

Ok, so vaguely in order. I mostly agree with the cheap GPS thing. However, I bought a zumo 550 when they were new and very expensive. Very. That GPS has been on nearly every bike (20+) since then, still works fine, and prorated cost me maybe $60 a year. So I'm not against buying good equipment.

Next, the commercial locks. The 396 came out in 2018, so if you've had a lock for 5 years it doesn't fit this gps. I found a commercially available lock for the 396 at $touratech, it's $175. Seeing as how the whole GPS is currently available for $270, that doesn't seem like a great deal. The free chunk of aluminum and the free chunk of stainless are more in line with my spending. I did have to buy the screws though.

Getting into machining and fabricating: do it. If you have the space for the machines, go big. If not get the harbor freight 7x14 mini lathe or something from littlemachineshop.com and go to it. You can learn a lot more from a tiny machine with no power than you can from a monarch 16". I started on a HF lathe from craigslist, made lots of stuff. Enjoyed it, moved up to my Clausing 10x24. Looking for bigger now. If I had been introduced to machining when I was a wee lad I'd have been much better at math. There's a lot of math. Get on the youstubes and look for blondihacks and this old tony. Also Mr. Pete. You literally can't pay for the kind of education they provide.

Oh yeah, fair warning. A lathe is the free sample of crack cocaine. Once you get one you'll need some tool holding, then some tools, then some carbide indexable inserts, then some cutting fluid, then some spare stock. Give a pig a pancake. Seriously, I went from a cheap harbor freight lathe to half my barn is now a machine shop and any tool less than about 5000lbs is fair game.

Moving on, the bastards at the amazons had false advertising and sent me regular screws with a security wrench so back they go. I ordered a different set of security torx so we'll see if they are correct. Regardless I installed the thing back on the bike using regular shcs just so the bike would be available for rides as needed.

Untitled by Uncle Grr!, on Flickr

Untitled by Uncle Grr!, on Flickr

As usual, this won't stop a dedicated thief. But then nothing will. This will however stop the casual to moderately motivated thief, which is all we can really hope for. I'm pretty happy with the final product, and once again now that I've done it a few times I'm able to reproduce it in short order.

[whodat]

In the interests of furthering this evolution and simplifying the design (mostly because I have the same kind of GPS on another of my bikes) I decided to see if I could make it more universal, simple, and not involve welding. So I grabbed random chunk of steel, a bit less than 1/8" thick and cut out a 1.75x around a 4" long strap. Bent one end up, drilled the holes for the GPS, drilled and tapped the bent bit for the security screw. Done. It's in paint now. This goes to show that this could be done with a hacksaw and a vise, a drill and a cheap tap.

Untitled by Uncle Grr!, on Flickr

Untitled by Uncle Grr!, on Flickr

Untitled by Uncle Grr!, on Flickr

[40Xshooter]

I have a GARMIN 396 LMT also. I just push the button on the bottom of the cradle so it releases, put it in my trunk, lock the trunk and I'm DONE. If they want the GPS they're gonna GET the GPS no matter what you do (ask me how I know that).
Very nice work on the locking device!

[JayBros]

...Oh yeah, fair warning. A lathe is the free sample of crack cocaine. Once you get one you'll need some...

Yeah, lathes and milling machines have farkles too.

[whodat]

I have a GARMIN 396 LMT also. I just push the button on the bottom of the cradle so it releases, put it in my trunk, lock the trunk and I'm DONE. If they want the GPS they're gonna GET the GPS no matter what you do (ask me how I know that).
Very nice work on the locking device!

That's what I used to do also. Now I just walk away. Thanks! It's fun to solve problems, even if the problems are only in your head. I know that unless the dirtbag has not just tools but specialized tools, they're not getting the GPS. With the unit in the cradle you can't access the bolts that hold the mount to the bike, you can't access the heads of the bolts that hold the cradle to the mount, and unless you have a security torx bit the right size you can't get the locking lug out. I even turned the sides of the bolts down so you can't possibly get a pair of pliers on it. It's as secure as it can be. And if I leave the wrench in the toolkit, removing the GPS when I need to takes all of an additional 30 seconds but even the wrench is secured by lock and key.

[JayBros]

For 40X shooter, I agree with whodat and did just what you do with your 396 but it became kind of a pita so I bought a Kradellock. I think the Kradellock 359, https://robertbeckerdesign.com/shop/...kradellock-359, will fit the 396 although you could check with Mr. Becker to be certain. I've had mine for four years+ now and leave the GPS on the bike all the time except for overnights in motel parking lots, including lots of time totally out of sight of the Spyder when sightseeing on tour. Yeah, a determined thief can get one if he really wants it but life's a risk and many Spyder farkles cost more than a Kradellock.

[40Xshooter]

For 40X shooter, I agree with whodat and did just what you do with your 396 but it became kind of a pita so I bought a Kradellock. I think the Kradellock 359, https://robertbeckerdesign.com/shop/...kradellock-359, will fit the 396 although you could check with Mr. Becker to be certain. I've had mine for four years+ now and leave the GPS on the bike all the time except for overnights in motel parking lots, including lots of time totally out of sight of the Spyder when sightseeing on tour. Yeah, a determined thief can get one if he really wants it but life's a risk and many Spyder farkles cost more than a Kradellock.

I carry a "HALF COVER" with me when I'm out and about and planning on stopping somewhere. I find that it prevents people from seeing your instrument cluster. It's not a "lock" per se, but it might detour someone from thinking badly. (It also keeps the seat cooler!)

[JayBros]

Valid point. I too use a half cover on tour but just at night.

[Rattlebars]

I see that Garmin ZUMO has come down in price considerably (less than $700). But the 4 inch screen is too small for my old eyes. My 56 has the "big" 5 incher and a sufficiently bright screen. Good info all around!

[whodat]

Probably a final update unless something weird happens. I got the security screws in and installed them, as well as adding another pivot hole in the bracket to move the GPS slightly higher.

First pic shows the screw as received (right) and as I turned it down (left) so there's no place to grab it with pliers.

Untitled by Uncle Grr!, on Flickr

Next shows the actual security feature. It's a regular torx but there's a pin in the center that disallows the use of a regular tool, it has to be one designed for this.

Untitled by Uncle Grr!, on Flickr

Yes I know the lathe work is crap. Apparently I have a chip in that insert. Still, good enough for what I'm doing.

Finally, I added the same style of screw in the pivot so that even that can't easily be removed so they can't just take the whole mount.

Untitled by Uncle Grr!, on Flickr

Again, pretty pleased with how this turned out, and now I have three different ways of doing it.

[JayBros]

That finished job is really worth bragging about. Bravo Zulu!

[whodat]

Thank you sir! BTW, when I say finished I mean I'm going to make another aluminum one just because it's fun and I just bought 25lb of aluminum off ebay for small money so I have a lot to work with...