Shop OBEX P1 Docs P2 Docs Learn Events
Micro Bolt Lock — Parallax Forums

Micro Bolt Lock

ManetherenManetheren Posts: 117
edited 2009-12-03 15:42 in General Discussion
Anyone know of an in-expensive bolt lock like the one here.

http://www.sdcsecurity.com/series.aspx?id=46

either surface mount, or jamb mount (preferable)

These would be nice for keyless access, but a little pricey.·

Either that or a good way to locally fabricate one.

Thanks.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Tia'Shar Manetheren

Comments

  • stamptrolstamptrol Posts: 1,731
    edited 2009-11-25 15:07
    You could fabricate this by winding a coil and using a spring loaded plunger in the core of the coil.

    But, if you're trying to duplicate a commercial quality lock with fail-safe/fail secure modes for less than the noted $100, I don't think you'll be able to do it.

    If its a just a learning exercise, the coil and plunger approach won't break the bank.

    You might also be able to adapt a servo or other motor to an existing inexpensive dead-bolt lock.

    Cheers,

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Tom Sisk

    http://www.siskconsult.com
    ·
  • bambinobambino Posts: 789
    edited 2009-11-25 16:13
    If it's a learner project, There is such a device found in the bottom of old dishwasher appliances. A spring loaded bolt, housed in a wire wound electro magnet, that operates the drain valve. It could do in a pinch.

    ·A better one can be found in some ancient computers that had the key lock function. It was a small selinoid that could lock in either position. Hard to find though!
  • kwinnkwinn Posts: 8,697
    edited 2009-11-26 05:25
    Many relay or solenoid valves will have the required coil and bolt. An angle bracket from the local hardware department would work as the latch.
  • T ChapT Chap Posts: 4,223
    edited 2009-11-26 07:30
    allelectronics.com has lots of little solenoids for uses like this.

    Do a search on the site for solenoid. I was just in there yesterday poking around and saw these.

    www.allelectronics.com/make-a-store/item/SOL-58/24-VDC-PULL-TYPE-SOLENOID/-/1.html
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2009-11-26 15:49
    The price list indicates $96.00USD each!!!! And these are the least expensive of their products.

    You can get a large variety of 12VDC or 24VDC solenoids for around $5USD each and fabricate your own brackets.

    Here in Taiwan, we have a door latch that opens from the outside with a cylinder key, opens from the inside with a button, or remotely with a electrical pulse and I am pretty sure that it doesn't cost $96USD. Very pricey.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Ain't gadetry a wonderful thing?

    aka G. Herzog [noparse][[/noparse] 黃鶴 ] in Taiwan
  • mctriviamctrivia Posts: 3,772
    edited 2009-11-27 22:17
    down side to a solinoid is it requires power to keep it in the unlocked state. a cheap servo could be used as a lock and would only require power during state changes.

    http://www.pololu.com/catalog/category/23 - $9

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    24 bit LCD Breakout Board coming soon. $21.99 has backlight driver and touch sensitive decoder.
  • T ChapT Chap Posts: 4,223
    edited 2009-11-27 23:43
    mctrivia said...
    down side to a solinoid is it requires power to keep it in the unlocked state. a cheap servo could be used as a lock and would only require power during state changes.

    http://www.pololu.com/catalog/category/23 - $9

    Allelectronics has a dual pole solenoid with separate wires per coil. Wouldn't this allow a voltage on one coil to move it one way, then apply voltage to the other coil to reverse it? I don't think it would require voltage to remain in either state unless I am missing something.

    www.allelectronics.com/make-a-store/item/SOL-122/DUAL-OPPOSING-SOLENOID-LINEAR-ACTUATOR-/1.html
  • kwinnkwinn Posts: 8,697
    edited 2009-11-28 00:32
    There are "latching" solenoids available that only require energy to the coil when moving the solenoid. The solenoid is a magnet that the coil either attracts or repels. At each end of its travel magnetic attraction holds it in place.
  • mctriviamctrivia Posts: 3,772
    edited 2009-11-29 00:59
    have a part number for a good cheap latching solinoid. it would be easier then a servo and just as good on energy.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    24 bit LCD Breakout Board coming soon. $21.99 has backlight driver and touch sensitive decoder.
  • ManetherenManetheren Posts: 117
    edited 2009-11-29 17:34
    the latching solonoid looks like the way to go for my project. Thanks for all the help. I will post later on the project as it is still in its in brain phase and I am in the middle of a long distance move.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Tia'Shar Manetheren
  • RiJoRiRiJoRi Posts: 157
    edited 2009-12-01 14:28
    Do NOT use a latching solenoid for real-world door apps!!

    (Unless there is also a crash bar.)

    Consider having a locked door, and a fire occurs. Power is lost to the solenoid, so it stays in the locked position. HOW DO YOU GET OUT?? freaked.gif

    --Rich
    (In fact, such a setup may be illegal in your area.)
  • BradCBradC Posts: 2,601
    edited 2009-12-01 15:17
    RiJoRi said...

    Consider having a locked door, and a fire occurs. Power is lost to the solenoid, so it stays in the locked position. HOW DO YOU GET OUT?? freaked.gif

    I'm glad someone raised this. It's for the same reason I won't use a "dropbolt" in any security application. They jam and people die.

    Please don't use any home made locking devices on any doors you might need to access in any form of emergency. Saving $100 on a lock is not worth your life.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    If you always do what you always did, you always get what you always got.
  • CounterRotatingPropsCounterRotatingProps Posts: 1,132
    edited 2009-12-01 19:31
    An appropriate coincidence here ...

    read RiJoRi's warning earlier today - just a bit before one of our local fire marshals arrived for an inspection.

    I mentioned the powered door latch to him - and he asked exactly what RiJoRi said: "so how do you get out if the power fails?"

    Accordingly, in every(?) US state such a device is against fire codes (at least for commercial buildings, which are more tightly regulated.)
    Those credit card style readers the hotels and motels have do electrically bolt the door --- but from the *outside* only. From the inside, you have to be able to open the door with "one hand motion and a push".

    I learned lots about fire codes and doors when I had to remove all 12 doorknob latches from our building to meet code.

    These codes exist often because people do dumb things - and the regulators have to then make sure that others don't do the same thing!

    Please don't become a statistic!

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  • mctriviamctrivia Posts: 3,772
    edited 2009-12-02 06:51
    obviously if you are planning to lock your house with something like this you need something that in case of power failure unlocks(leaving you at risk of theft) or has a mechanical overide.

    For myself I would want something like this for locking cuberts or the safe I want to build. In either case I would have a battery backup and it would not be a life or death situation if I could not get in do to power failure of both battery and main power. If you want electronic door locks for your house there are many very nice ones with both key and code entry.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    24 bit LCD Breakout Board now in. $21.99 has backlight driver and touch sensitive decoder.
  • ManetherenManetheren Posts: 117
    edited 2009-12-03 14:16
    this is for cabinets and safes just as MCTrivia stated in his last post. I understand the legalities and difficulties with using as primary locks on doors and windows for household use.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Tia'Shar Manetheren
  • CounterRotatingPropsCounterRotatingProps Posts: 1,132
    edited 2009-12-03 15:42
    Well Manetheren,

    just goes to show that we were thinking like engineers: think, plan, design for the worst - but get too busy to properly read the specs ... over design ... over budget ...

    Client then says - hey I just wanted a "CABINET" lock, not a human-entry lock.

    DOH!

    (If we'd clicked that link you did provide in the first place, we'd have known better [noparse]:)[/noparse])

    cheers,
    Howard

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Sign In or Register to comment.