Mini project: Keypad mount

[AdeV]

In order to add keypad security to the workshop, I need to mount a keypad (well, duuuh) on the steel door. Cue some milling....




Next steps, cut the piece out, radius the edges, a bit of spit & polish:



Note the rather large problem on the right hand side: the slitting saw decided to ride up, which cut into the finished item. Unfortunately, I didn't have enough material left to mill the problem away, and this part has already taken too long to make, so it's staying as it is.

Here it is bolted the door:



Next steps - wire it up & get the servo mounted on the back of the door to work the lock.

[John Stevenson]

Wot 'appens when the barrery goes flat and you are locked out ?

.

[AdeV]

I use the key...

[Divided he ad]

Nice!

Shame about the saw mark.... I'd fill it with something and make a feature of it! 


I'd like to see how this lock works too...Got a steel door to go in my shop soon I think?  That's if it's not a secwet?




Ralph.

[mklotz]

Make up a small card with instructions for operating the keypad.  Install it in the saw slot.  People will think it's a feature, not a fault.  (Kind of like Microsoft software.)

[AdeV]

LOL Marv - I like that idea... might just do that It'll be a bit less conspicuous once the weather hood is in place, but, nice thinking...

Ralph - also good thinking...

Originally, the plan was to have a servo, mounted on the backside of the door, twist the lock's knob (fnaar):



However, the lock is the style pictured above, and for some reason the servo is unable to pull it more than about half way. Probably I need to get my diameters spot on, etc; but then I can't operate the lock manually from the inside.... so plan B: I will make some kind of shaft which passes out of the back of the lock, and is attached directly to the thingybob that goes in & out (don't know it's technical name...). The other end of the shaft will be in a floating slot thing, which the servo can pull on (which opens the door), but which also allows the thingybob to go in & out without moving the servo; which allows the door to open on the key or knob, and also to close when the striker pushes the thingybob in.


Exact details will be worked out..... later.... I've not milled a deep enough recess for the LED wires; so they're being squished when I bolt the device to the door, which is causing problems with getting the correct - or, indeed, sometimes, any - LEDs to light. So it's back on the mill with it tomorrow night, to make a bit more room for the wiring... I may also mill the front off the LEDs, so they fit flush with the front, and finally I may glue them in place, rather than simply relying on the pressure of the door on the back to hold them.

Mk2 would probably have a fitted back, which would allow me to make good the wiring before mounting it up, and be at least moderately confident it'd all work when there...

[Divided he ad]

Ade,


Just a thought... As you do!




What about making the catch plate pivot and the solenoid pin have a bevel on one side?

Then when you enter the code the pin moves down and lets you in when the catch plate pivots open. Stopping at a pre-determined point so that when the door shuts it pulls the plate back into the closed position and the beveled edge of the pin allows it to spring down and then shoot up into position.

Just a thought, I'm sure if you wanted you could elabourate on it with different pins etc 




Just a thought 




Ralph.

[AdeV]

Ralph - that's certainly close to the usual setup with an electronic lock; the catch plate is normally what does the work.

The problem I have is my door is outward opening - no prob with the lock itself, I can reverse the thingumyjig to work correctly, but as a result the "catch plate" is actually the fixed door frame, with a 6mm pin welded to it to provide additional "catch". Tomorrow, I'll take a pic to show you what I mean.

I will, at some point, put a similar system in the office; for that, I'll probably just use an outward-opening electronic catch plate, rather than fiddling with the lock plunger.

[andyf]

Ade, those Yale-type nightlatch locks aren't very secure. Google "bump key" to see how vulnerable they are.

Andy

[Divided he ad]

I know what you mean Ade, no worries. I just thought it might be a possibility.

If the locks are as bad as Andy says, maybe a solenoid shoot bolt would be a good idea? with a high security key as a fail safe?

Or are we making a door full of locks (with a window next to it  ) here?



Ralph.

[Bluechip]

Adev

Not sure if you've posted.. longish thread ... but ..

Do you have the correct secure hinges for outward opening doors?

Otherwise, toe-rags can drive out the pin, then the locky end won't matter, 'cos the door will open from the hinge side ..  

Similar to these, the pins stop the door being opened if the hinge pivot wotsit is removed ..

http://www.screwfix.com/prods/22313/Ironmongery/Hinges/Flush-Hinges/Security-Hinge-Grade-13-Satin-Stainless-Steel-102-x-76mm-Pack-of-2

Dave BC

[AdeV]

I should probably point out, this is not the primary security: there's a "proper" padlock, under an anti-bolt-cutter hood - all heavy duty steel plate, on the door itself, and the site gate is secured in a similar manner. The main reason for adding the yale type lock & keypad is so I can have the main unit locked during the day when I'm in the office, to stop oiks & general scum from just wandering in - without the hassle & aggro of locking the main padlock all the time. It also means people can't just wander in when I'm using the machines, which are at the far end of the unit.

It also means I can shoot out for a sarnie at lunchtime without having to faff around with padlocks & stuff. The site is occupied during the day, just not my unit.

Ralph, you wrote your reply while I was writing mine, but I think the above covers your points too 

Dave, I can't remember what kind of hinges are on the door, I'll have to check tomorrow...

[Bluechip]

AdeV

Yup, check the hinges. One of my biking mates was done over about 8 yrs ago. Tried it myself. A battery screwdriver with a Dremel type cut off disc went through the pivot on a scrap hinge in about a minute. Drive out the pivot, and the hinge just falls into two parts. It's that easy. Those pins are not very hard.

Once the hinges are shot, it wouldn't matter how good the 'five lever BS' locks are. You are in.   QED

Dave BC

[AdeV]

Dave - a determined enough thief will get through anything, given enough time. The hinges on my door are pretty chunky, a dremel type tool would get them eventually, but oxy-acetylene would be quicker. Mind you, once they've got the little door open, they'll need to work through another padlock to get the big doors open, then shift the bus before anything big will come out... but that's another story.

On with the show.... I was wondering how difficult it would be to alter the lock to drive the plunger directly. In fact, it was pretty easy in the end:



This shows the hole through which a long bolt will protrude, which is screwed into the end of the plunger thingumybob. Due to the drill wandering a bit, I couldn't tap it all the way through; but the bolt's got plenty of thread to hang on to, and it doesn't interfere with the normal lock operation at all. Bonus.

A quick trip to B&Q separated me from a breathtaking £3.58 in return for a very small handful of 70mm bolts. Next question.... how to make a suitable device for the servo to catch the bolt & pull it? The answer, it turned out, was really simple: Bolt a washer to the end of the bolt, and just use a regular servo horn. Add a bracket to hold the servo in place, et voila:



That's in the normal position; here it is with the lock pulled back:



That 15kg servo handles the lock plunger with consummate ease - much better than trying to twist the handle, which wasn't working at all well. What's more, if you twist the handle, or the key, or just close the door using the regular yale-type mechanism; the bolt moves & doesn't bind or stick on anything. It did scrape a couple of threads at one point; if that proves to be a problem in the future I'll just file part of the bolt down a bit so it doesn't bind up.

Because I can't do anything the simple way.... first, press "A" to get the machine's attention. The "Attention" lamp lights:


Oops, wrong combination:


That's better, now the door will open - as long as the green light is lit:


So, all I need to do now, is tidy the installation up a bit  :



I'm not sure how good that 12v supply is for the servo either.... I'll replace it with one of those multi-volt supplies from Maplins.

That's pretty much it for this project, other than finding a suitable box to put the gubbins in, and adding a weather shield to the keypad.

[Divided he ad]

Ingenious    


Very effective Ade.



Just one thing....

I'll replace it with one of those multi-volt supplies from Maplins.

Always check that the voltage is what it says.... I've had them 3-8volts higher than prescribed!    Blown up all sorts that way!!



Thanks for sharing this lot.... I might be PMing in the near future when I get my new workshop door in  




Ralph.

[AdeV]

Ralph - Thanks, and PM anytime. I'll share what I can, but be aware that this project is off the scale when it comes to bodgery...

Anyhow, I finished it up this afternoon (excepting the weather shield) - and I will probably re-visit the power supply, I fancy using a 6v lead acid battery with constant trickle charge; that way the lock will continue to work in power outages. Then again, the key still works, so is it worth the faff?

Now, I happen to have a box lying around for this project. I bought it not long after I started planning the project.... which was a long long long time ago. In fact, here's what started it all off (click the image for a big version):



Check out that date: June 1983... I probably bought the stuff a few years after that, so 1986/87 maybe. However, one - or maybe both - ICs were not available in the Maplin catalogue, and as a result the project never got any further than an empty box......


....until now.

Cue some spectacularly awful bodgery:



The white plastic thing is a modified "Twin Keystone jack surface mount box" (available in B&Q) fitted into a milled & hand filed hole cut in the box. Two minute self-tappers hold it in place. The Arduino itself is held in place with nothing more than blind luck and a touch of brute force: The USB socket protrudes off the front of the board a little way, so a hole was drilled & filed to shape, until it was a nice tight (but sliding) fit. The board is then packed at the back with two uprights, each with a cut-out at the appropriate height. The whole lot is then just wedged in place... Awful, really really awful, I know... Finally, the cables were fettled into position, the keystone jacks clicked into place; and the servo lead poked out of another hole which was already in the box. I'd have preferred to use some kind of plug, but nothing fell to hand.

So, with the lid screwed on, all sins are hidden  The sticker covers another hole I'd cut in the box in a past life:



Finally, mount it on the door, plug in, add 6v from a wall-wart power pack I found lying around - being a 2.5amp unit it puts enough current out to run the servo without starving the Arduino. I also renamed it the "Lockuino", for obvious and corny reasons. And here it is, stuck to the door with sticky pads:



2 tasks remain: 1) Extend the power supply lead so it can be plugged in permanently; 2) make that keypad weather shield before it rains...

 

[Divided he ad]

Very nice, very neat (once the lid's on  )

but be aware that this project is off the scale when it comes to bodgery...

I think you'll find that is more like      

That'll be a future project for me I'm sure, but I have loads to get out of the way first!

It's about time we saw what that "door" was the end of too    I'm assuming Colin owns the very dusty motor!? 



Rain!!!! You trying to jinx us man!? I've just gotten used to this glorious sunshine    (been off all day.... Basking in it  between the workshop and the house that is  )




Going to wash the motor now







Ralph.

[CrewCab]

Just loved this thread guys, I'm grinning ear to ear ........... lets be fair a key would be a lot less hassle, but obviously   got in the way .......... respect  

Marv's comment ......... Re: Microsoft

Make up a small card with instructions for operating the keypad.  Install it in the saw slot.  People will think it's a feature, not a fault.  (Kind of like Microsoft software.)

made me chuckle .......... though personally a bit of filler and spray paint should do fine  

Great work Chaps  

CC

[AdeV]

I must admit, financially this thing makes no sense whatsoever. I mean, here's the parts list (with approximate prices):

3"x3"x2" Aluminium block (the servo holder is made of the remains of the underside of the keypad holder) - £5
1x keypad £1.50
3x LEDs £0.50
Some salvaged wire (mostly Cat5e network cable) & electrical insulation tape : £1 say
2x network plugs £0.25
2x network sockets £0.50
1x dual surface mount network socket £2.00
1x Acrylic box £3.25 (guess)
1x high power servo £10
A bit of steel & some welding, to hold the lock off the door £free, as it happens
1x ERA cheapo Yale type lock £20
1x Arduino CPU board £25
1x PSU £5

Total outlay, about: £74

Entertainment value in making & using the thing: £priceless. 

Things I Learned Along The Way:
 - Slitting saws need to be watched like hawks at all times
 - Don't crush the LED wires, it won't work
 - Chinese keypads are fine, but watch those solder pads

I also had a major nostalgia moment; whilst filing one of the holes in the acrylic box, I got a whiff of the melted/cut plastic - took me straight back to school it did, and the many hours in the "CDT" (Craft, Design, Technology) labs cutting, filing and sawing acrylic sheets for various long-forgotten and long-lost school projects.

[CrewCab]

I also had a major nostalgia moment; 

So it was all worthwhile then 

CC

[Divided he ad]

Entertainment value in making & using the thing: £priceless.   

Can't argue with that 



Good fun project with a practical application at the end of it 


If we worked out what most of the things we make would cost in the "real world" then we'd all be either poor (made for ourselves) or stinking rich (if anyone would pay those unbelievable prices!)   






Ralph.

[SAM in LA]

Nice!

Shame about the saw mark.... I'd fill it with something and make a feature of it! 

Ralph.

Here in the US, if the burglar cuts himself why breaking into your shop, he can sue you for the injury. 

SAM

[AdeV]

The same sort of madness affects this side of the pond too, Sam

There's only - in 15 years - been one burglary here. The chap who owns the place spoke to "someone he knows", which about 2 days later resulted in all of the stolen goods being returned, and someone spent some time in hospital getting over some broken limbs. The place has never been touched since (touch wood).

Just to add a little footnote to this project, came to it this morning & it wasn't working... seemingly random LED blinks, unresponsive, etc. Well, much diagnosis later, I discovered that two solder blobs happened to be touching on the keypad, which meant the machine thought the "A" key was being pressed continuously. Oops..... Double-whammy, when I went to fix it, one of the solder pads broke off. Damn!  Eventually, I had to disassemble one of the broken keypads, scratch the green layer off (the solder mask IIRC) a few mm of the tracks, and solder directly to them. It was painful, slow and tedious, but I got there in the end; re-assembled and all is well again. Phew!

[DMIOM]

....... much diagnosis later, I discovered that two solder blobs happened to be touching on the keypad, which meant the machine thought the "A" key was being pressed continuously. Oops.....

To be honest, I was grimacing when I saw the keypad and the swarf when you were milling its holder:

[AdeV]

....... much diagnosis later, I discovered that two solder blobs happened to be touching on the keypad, which meant the machine thought the "A" key was being pressed continuously. Oops.....

To be honest, I was grimacing when I saw the keypad and the swarf when you were milling its holder:

Don't worry, it wasn't sat there all the time! That's just a posed photo...

The few bits of swarf visible on the keypad were from where I was trial-fitting it. In the end, I used a different keypad (I bought 5 in total), but what with the solder pad problem, I've ended up wrecking every single one, so the k/p that's actually in use might be that one, or maybe not, I've no idea...