Another Sound Reactive Target Idea

[rnabholz]

Some of you may have followed my Bell Target Project thread (http://gatewaytoairguns.org/GTA/index.php?topic=466.0)

While I was searching eBay for the bell I used on that project, I came across another device that I thought may have application for this kind of target.

The device is a door/window alarm.  It consists of 2 pieces, the alarm box, about 2" x 1 3/8" and a magnetic bar.  When the alarm is turned on, the alarm remains silent as long as the magnetic bar is kept within about 1/4' of the alarm unit.





They were certainly cheap enough, they were less than $5 for 2 units shipped from Hong Kong! (don't ask me how they make any money!) So I ordered.

Now that they are here, it seems it would be very easy to incorporate them into a sound reactive target.


Using similar construction to my bell target the mechanism would center around a hinge, centered over the target hole on the back side of the target face.  Simply use double sided tape (which conveniently comes with the alarm unit) to attach the alarm unit to the back side of the target face parallel to the edge of the  hinge, and attach the magnet bar to the hinge, again parallel to the edge.



When at rest, the magnet bar will keep the alarm silent, but when the hinge is struck by a well placed shot and the hinge swings up, separating the bar from the alarm the alarm will shriek until gravity returns the bar to the resting position.

The magnetic bar contains no electronics, so it should have no issue with the bouncing around, and the alarm unit with the electronics remains stationary.

The alarm is quite loud, and even a short blast is easily audible.

Of course this is all theory at this point, I will not have a chance to work on it for a few days, but in the mean time, I would love to hear all of your ideas on how to make it better.

Having heard the alarm, I propose that it be known as a "Banshee Target"

Rod

[gene_sc]

What an imagination you have.. That is another great sound reactive target idea. I gotta buy a couple of them also.. Very simple design for sure. I assume the alarm uses battery power. There would have to be a solid barrier in front of alarm itself to keep my flyer's from hitting it..

Thanks again for a great idea. Your the man.. Love the name Banshee Target..

[Jay]

WOW for "someone with no real skill's" as you said on first post,you sure do have some great idea's!!!This one is excellent just like the last,would you remember the address of the place you got those from? I got to get building some of these.

[rnabholz]

What an imagination you have.. That is another great sound reactive target idea. I gotta buy a couple of them also.. Very simple design for sure. I assume the alarm uses battery power. There would have to be a solid barrier in front of alarm itself to keep my flyer's from hitting it..

Thanks again for a great idea. Your the man.. Love the name Banshee Target..

Thanks Gene.

As I picture it, the alarm is on the backside of the face, safe and sound. I plan on using the big washers like on the bell target to protect the front side.

Yes it does run on batteries, 3 button cells, also included! I don't know how they make money....

Hope to put one together sometime this week. 

Thanks for the interest,

Rod

[rnabholz]

WOW for "someone with no real skill's" as you said on first post,you sure do have some great idea's!!!This one is excellent just like the last,would you remember the address of the place you got those from? I got to get building some of these.

Thanks Jay,

Here is a link to the product and vendor I used:

http://cgi.ebay.com/Wireless-Door-Entry-Security-Sensor-Alarm-Bell-Chime-/270595796305?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item3f00c42d51

Rod

[rnabholz]

Undertook to build the first Banshee Target tonight.

Decided to use 2x6 stock for the frame.  Unlike the Bell Target which benefited from the mass of the bell, this will be a relatively lightweight target, so the thicker boards will add some needed mass.  Two pieces 5 1/2" square

The treatment of the front was the same, 4" washer and a second inside of that with a 3/4" opening.

On the back, the hinge is attached directly to the back side of the face board.  The alarm is positioned and attached with double sided tape.

I became concerned about the force the sensor bar might encounter as it swung up to the top of the hinge's travel and hit the hinge leaf.  I decided to add a couple of round tabs of the loop side of velcro to cushion the impact a bit.







The first test found that the duration of the siren call was way too short, the travel of the hinge was very fast.  It was too light and the pellet easily over energized the mechanism.  I decided to add some weight using a short bolt and nut through the hinge.  That seemed to work better, it now gave about a 1 second scream on impact.

I would still like to have it last a bit longer.  It occurred to me that if I added a rubber button that the end of the hinge would strike upon returning to the rest position, we could get a rebound that would cause a second siren call.  Might give that a try and see what I can do.

Any ideas out there?  For now it works, just could be a bit better with a tweak or two.  That's half the fun!

Rod

[Pete]

Hi..
Thats pretty kool....

That magnetic bar switch...
they are called "read switches" you can buy them
with out the alarm integrated in them..They have two pieces
with terminals on one section for two wires... they work by using
the magnet to hold a spring loaded bar that bridges two terminals
clear of the terminals..once the magnet is out side its Field range
 the spring pushes the bar across the terminals forming a cercuit ...

Pete

[Jay]

Rod I think when I build mine I will use a longer/heavy hinge an see if that will slow swing time down an I will most likely place a strip of pipe insulation along the top to stop the slam you were finding?I have one question for you, are you getting any pellet splatter in on your main box?

[Jack]

That is an absolutely awesome idea.  Thanks for the mental effort!

[rnabholz]

Rod I think when I build mine I will use a longer/heavy hinge an see if that will slow swing time down an I will most likely place a strip of pipe insulation along the top to stop the slam you were finding?I have one question for you, are you getting any pellet splatter in on your main box?

Jay, a heavier hinge may be the answer.  The difficulty lies in balancing the weight of the hinge to the varying power of different airguns, but a happy medium should be attainable.

Regarding pellet splatter hitting the alarm box, if you look close in the pictures above you can see the gray marks on the base board from pellet splatter.  A bit is getting on the very bottom corner of the alarm box, but it does not appear to be marking it in any way, so I don't think it is in any danger.

I have been thinking about this overnight and have another approach in mind - I will post it in the next response in this thread.

Thanks

Rod

[rnabholz]

After thinking about how to overcome the issue related above regarding the overabundance of energy making the siren duration too short, it dawned on me that the answer may be not try and beat it, but to use it.

So........let me present Banshee Target V2.0



This version is more of a spinner type target.  The magnetic bar is mounted on a steel bar that when struck will swing up and over the top of a crossbar and continue to do so until the energy is expended, at which time it will swing back and forth until it finally settles back into the starting position.

During the entire duration of the spinning and swinging the alarm will be activated and deactivated as the magnetic bar passes by and back and forth, which should make for a significantly longer siren duration (and quite a racket too...)

The front of the target face could be protected with some 2" wide steel sheet stock down both sides of the swinger slot and a bit across the bottom.  You can get this stock at most hardware stores and cut it wih a hack saw.

Need to walk the aisles of the hardware store to find the stock or suitably adaptable piece for the swinger.  Needs to be fairly stout to withstand the impacts, but workable because we need to bend it to create the channel for the rod it will spin on. (all of this could be a lot simpler if I could weld, but making it out of readily available components makes it much more accessible to more folks)

The rod could spin in a couple of appropriately sized eyebolts screwed into the top of the face board, and if we used a long bolt or all thread, a couple of washers and nylon locknuts could hold every thing nicely centered in place.

I think this holds great promise.  We do end up making the target a bit bigger, but only longer, not necessarily wider.  The sensor bar is only about 1/2" wide, so your target could be as narrow as that.

Having the target spin does add another dimension of visual feedback along with the auditory feedback from the siren, which does add to the equation too.

To the Hardware Store!!!

Rod

[Jay]

Brother you sure do enjoy this, an I enjoy all your idea's!!! Keep them coming!!!Try a flat paddle(the arm flat then circle)an place the magnet on arm so it will not take as much direct impact from the shot?

[uncle paulie]

For the swing mechanism, you could use the same strap hinge, drive out the pin and cut the center section down to the desired width.

[lampy]

I was talking to a guy today who uses shot gun shell primers as the bullseye for a reactive target..... might be kind of fun to have the sound of a primer going off when you hit the target of course you would have to "reload" your targets each time you scored a hit.

[rnabholz]

For the swing mechanism, you could use the same strap hinge, drive out the pin and cut the center section down to the desired width.

That could work.  I'll take a look at it,  Thanks

[Jay]

Lampy I have to admit I keep some in my pellet case,I just place them on edge of target board!?! I also keep small pistol primer's for even harder shot's, they sit perfect in a .177 hole (just don't tell anyone else O.K.).

[RedFeather]

Please don't post about using centerfire primers as targets.  This was hashed over on the Yellow forum some time back.  If you read the directions for handling and safe reloading, you will find that primers can be extremely dangerous.  And one shooter had the reactive target come back and target him as he was hit by the primer's internal "anvil" when it blew out.  Read the safety warnings on primers.  They're no joke.

[lampy]

Please don't post about using centerfire primers as targets.  This was hashed over on the Yellow forum some time back.  If you read the directions for handling and safe reloading, you will find that primers can be extremely dangerous.  And one shooter had the reactive target come back and target him as he was hit by the primer's internal "anvil" when it blew out.  Read the safety warnings on primers.  They're no joke.

point taken    Safety First!