Montana 600 Amps Rugged Mount Thumb Screw Mod

To start off I bought a Garmin Montana and it has been the most useful accessory I've purchased in a long time. I'll finish up the write up on that one soon but man, awesome... Next I bought this Amps rugged mount for the Montana. It works great and love it but have been less than pleased with the silly safety torx lock screw and tool needed to lock your GPS into the mount.

http://amzn.com/B0055BJBMC



Its a really nice quality mount. It feels very solid and should take quite a beating. I rode around for a little without the safety screw tightened down and really didn't enjoy that. The thought of ejecting my beloved brand new GPS was nauseating. After a day of using the silly torx tool that comes with the mount I made the decision that this has got to go and a simple easy to use thumb screw needs to be installed. And unfortunately its not as simple as just unscrewing this one. I wish it was but there's a little nasty in there that you're going to have to take things apart to get to...



So with that pour a glass of your favorite whiskey or crack open a beer and lets DIY.
I'll get right to the good stuff and start taking things apart and modifying them.
PICTURES PICTURES PICTURES!


STEP-1
Start with removing these 4 inserts. I wouldn't have if one hadn't fallen out, I figure remove them now so one doesn't get lost.


STEP-2
Remove the 6 little Phillips screws and remove the back plate. It lifts right off and none of the springs are going to jump out so don't worry.




STEP-3
Remove the two springs. I used one of the really tiny flat head electronics screw drivers in my kit. Just don't pop them out and send them flying across the room. Work smarter and be careful to not loose them. They'll be a pain to replace if you do. The plastic pieces lift right out without the springs in place. Piece of cake! I will admit that the center spring is a little harder to do than the one on the end of the slider. Just get that tiny screw driver in and slide the spring up and off of its retaining pin and it'll come right out and apart.



STEP-4
Here's the little nasty. That little E-Clip keeps the screw from coming out. I understand why they put it in there but it's just silly. The screw must screw into and then through the housing. The clip just prevents you from removing the screw. That little part on the screw without threads also lets the screw float on the housing and the little spring keeps the screw in position when not engaged with the base of the mount. When engaged you cannot press the button in to release the GPS. This locks the little hooks into the GPS and it's not going anywhere. Just use the tiny screw driver again, pop off the E-Clip and remove the screw.




Step-5
Hopefully you're not on your second glass of whiskey by now. You'll need to go the the hardware store if you didn't read ahead to figure out what materials you'll need. This is what I ended up getting. I should have bought 3 more screws than what I did. I didn't realize how soft and easily destroyed they would be.


M3-0.5 x25 Screws - You can go with 20mm if you want, I like having the extra material.
Turn Knobs - I found these lamp knobs that are close to the M3 threads.
O-Rings - I wanted these to help hold the screw (they're cheap).




Step-6
So as I mentioned the knobs I bought are close to M3 threads but they are not. I couldn't find a 3mm tap and because the knob was aluminum I figured I'd just sacrifice a screw to make the threads work. I just didn't know I'd destroy two of them to do it. I know this not the right way but it works. If you have or can find an M3-0.5 tap I recommend using that. Even better use a knob with M3-0.5 threads. I did not want to use a stack of nuts. That looks like poop and this is much better.

Hold the knob in a set of vice grips and slowly get the screw started as straight as possible. Tighten a little bit, back it out, tighten a little bit, back it out. Do that until your happy with how much of the threads are in the knob. I did a little over a 1/4 inch and destroyed two screws to do it. But once you're there and you're happy with it slather it all in RED loctite, screw it all together and clip the head off the screw.



Step-7
I used my drill press for this because I don't have a lathe. But pretty much anything with a drill chuck will work. I used a file and slowly removed the threads as it spun. I wish I had another screw at this point. I removed way to much material and it looks like crap. But I don't want to go back to the store and it'll still work. Just don't be like me and only remove the threads. Don't worry about making it exactly like the torx screw, just remove the threads so it wont engage with the housing when installed.



Step-8
Cut it to length. Remember, its easier to cut a little more than it is to fix it when you cut to much. Just take your time and do it once, be sure to debur the edges so you don't run the risk of cross threading the brass insert in your mount. If you're going to use the o-rings make sure they are included when you're cutting the screw down.




Step-9
Re-install the springs. Put the plastic pieces in first then use the tiny screw driver again. Get the spring started on the retaining pin then compress it and install it. I don't have to mention how easy it is to lose these but I will. Don't lose these springs. Work carefully. You'll be tempted at this point to see how well your screw works. DON'T. If you do at least set the back plate on. The springs will compress and very easily take flight. Just be patient.



Step-10
Last step! Reinstall the back plate, 6 Phillips screws, 4 Inserts and your really awesome fancy thumb screw.



YOU'RE DONE!




Couple additions to the junk drawer...


And that's it! Re-install your mount on your bike and go ride with the ease of locking your GPS to the mount with a thumb screw. As always there's a dozen ways to do this and my way is not necessarily the best way. I like having the O-Rings but you could very easily omit them. DIY write ups are more about information than instructions anyway. That was the goal with so many pictures. It was a pain to take them all. Next time I'm taking the pictures with my phone. The Samsung Galaxy is 10 times easier and better than my Kodak M1033 point-n-shoot. There's another addition to the junk drawer right there... Hope that helps someone who decides to go with a Garmin Montana and an Amps Rugged Mount some day.

Cheers everyone!



MA$TER_E

10/10 MasterE I love the write up and the pictures as always are ace as you point out loads of different ways to make the screw but it's the disassembly which is the important part, sadly I never go anywhere where I would need a GPS unit lol.

Why not ? What about adventure to mongolia in summer

i have to report that i seem to be an imbecile when it comes to electronic gadgets, ive got a 2nd hand uniden igo35, but... i cant figure out how to get an adress into it, or actually operate it at all..., ive decided i will stick with the maps, im sure i will end up smashing it if i dont get rid of it!