Sideband
Guest
If you've tested this at all yet you probably found rust to be a big problem. Just touch one of the platters with your fingers and look at it in a few days. You will see rusty fingerprints.
Joe
Joe
Surface signalling mirror
- Thread starter Zero
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miketsp
Contributor
I use a camping mirror, made of polished stainless steel. After 2 years of regular use it's still as new as the day I bought it. Cost me all of US$4.
There is an aiming technique.
Hold the mirror in one hand close to your eye.
Stick out the other arm and make a V with the index & middle finger.
Now put the target in the center of the V and flash the light from the mirror across the fingers.
With this technique it's also easier to send morse since you know when the light is on a target a long way off and you can't see the light hitting the target.
Doc Intrepid:
There is an aiming technique.
Hold the mirror in one hand close to your eye.
Stick out the other arm and make a V with the index & middle finger.
Now put the target in the center of the V and flash the light from the mirror across the fingers.
With this technique it's also easier to send morse since you know when the light is on a target a long way off and you can't see the light hitting the target.
Bratface
Contributor
Get a mirror.
OP
Zero
Contributor
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Just to follow-up some further testing....
No rust from finger prints
No damage from sitting in salt water for extended periods of time
Extremely durable, chip and scratch resistant
and long a virtual endless supply of free replacements....
I haven't come across one reason not to use them.
No rust from finger prints
No damage from sitting in salt water for extended periods of time
Extremely durable, chip and scratch resistant
and long a virtual endless supply of free replacements....
I haven't come across one reason not to use them.
Boogie711
Guest
Zero:
I believe what you mean to say is "I wanted to use them, I already had my mind made up, and when people pointed out the fallacies of my plan, I decided to use them anyway. This way I can prove I'm smarter than you."
Nice try. But you failed.
OP
Zero
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Boogie711:I believe what you mean to say is "I wanted to use them, I already had my mind made up, and when people pointed out the fallacies of my plan, I decided to use them anyway. This way I can prove I'm smarter than you."
Nice try. But you failed.
Interesting, I thought this was a forum to discuss topics, share thoughts and opinions based on experience and some form of actual research. Sorry if you've drawn the wrong conclusions, I was only providing some actual data to counter the some opinions didn't stand up to a little research.
ECVdiver
Guest
Internal Hard Drive Parts
What's Inside?
David Risley
All hard drives share the same basic structure, varying only in how each part is used and the quality of the parts themselves. The platters, spindle motor, heads, and head actuator are inside the drive, sealed from the outside. This chamber is often called the head disk assembly(HDA). The HDA is rarely opened, except by professionals. On the outside are the logic board, bezel, and mounting equipment. Below, I will describe each of these components.
The platters are the disks inside the drive. Platters can vary in size. Often the size of the drive, 5.25" or 3.5", is based on the physical size of the platters. Most drives have two or more platters. The larger capacity drives have more platters. They are usually made of an aluminum alloy so that they are light. The newest and largest drives make use of a new technology of glass/ceramic platters. This is glass with enough ceramic within to resist cracking. This glass technology is taking over aluminum in the hard drive industry. Many popular manufacturers already use it, including Maxtor, Toshiba, and SeaGate. Glass platters can be made much thinner than aluminum ones, and they can better resist the heat produced in operation.
Alone, platters are not capable of recording data. Each one is coated with a film of some magnetically sensitive substance. The oxide media is one of the ways of doing this. A mixture of compound syrup is poured on the platter, then spinned to evenly distribute the film over the entire platter. This substance has iron oxide as a main ingredient, explaining why many platters you may see will be brownish-orange. The other main media consists of a thin film of a cobalt alloy which is placed on the platter through electroplating, much like chrome.
Just some thing I found on line to further the discusion
What's Inside?
David Risley
All hard drives share the same basic structure, varying only in how each part is used and the quality of the parts themselves. The platters, spindle motor, heads, and head actuator are inside the drive, sealed from the outside. This chamber is often called the head disk assembly(HDA). The HDA is rarely opened, except by professionals. On the outside are the logic board, bezel, and mounting equipment. Below, I will describe each of these components.
The platters are the disks inside the drive. Platters can vary in size. Often the size of the drive, 5.25" or 3.5", is based on the physical size of the platters. Most drives have two or more platters. The larger capacity drives have more platters. They are usually made of an aluminum alloy so that they are light. The newest and largest drives make use of a new technology of glass/ceramic platters. This is glass with enough ceramic within to resist cracking. This glass technology is taking over aluminum in the hard drive industry. Many popular manufacturers already use it, including Maxtor, Toshiba, and SeaGate. Glass platters can be made much thinner than aluminum ones, and they can better resist the heat produced in operation.
Alone, platters are not capable of recording data. Each one is coated with a film of some magnetically sensitive substance. The oxide media is one of the ways of doing this. A mixture of compound syrup is poured on the platter, then spinned to evenly distribute the film over the entire platter. This substance has iron oxide as a main ingredient, explaining why many platters you may see will be brownish-orange. The other main media consists of a thin film of a cobalt alloy which is placed on the platter through electroplating, much like chrome.
Just some thing I found on line to further the discusion
Zero:
I agree...this is the DIY section....Do it yourself...I would kindly like to ask those who clog up these discussions with doom and gloom posts to refrain. If you would rather "buy it yourself" there are other forums for that...just go to the forums page and look for "buying gear"
Now as far as the mirror goes, I got a HD disc from my IT guy at work and I am going to fashon out a 2-1\2'' X 1-1\2" mirror with a 3\16 sight hole. This wont happen until after the holidays, so I'll post pics in a couple of weeks. Then I am going to beat the crap out of it to see how well it holds up. Im thinking it will fair well in a BC pocket. I'll keep you posted...
Some things to note about Signal mirrors..The commercially available glass ones crack easily...even the Mil Spec ones. When I was in the Coast Guard we threw broken mirrors away constantly. The plastic Mil Spec mirrors will crack and haze over time...a lot of people dont know this, but those poly carbonate mirrors can be used to start a fire. Scrape the side to get plastic shavings and touch a match to it....burns like napalm...and the stainless mirrors will bend and warp, and if exposed to salt water will develop rust.
Tips on use...even if you dont see vessles or aircraft in the area, continue to sweep the horizon. If you do spot a Vessle or Aircraft continue to sweep them with your signal until they reach you.
Mambo Dave
Contributor
Wait a sec: Who pointed out the fallacies in the plan? A poster begins a discussion of hard drive platters, then numerous people take the thread off topic by talking about the problems of using CD's as signalling devices.
If some of these singal mirrors admit they don't have the reflective quality of a true mirror (and have a star hole in the middle), and the platters have much more reflectivity than a CD (plus a hole in the middle), I'm still curious as to how they would perform at distance and how they hold up in a pocket.
If the platters are simply oxide coated, I'd expect the coating to wear off (much like a CD) whilst in a pocket against shears and a flashlight. (Is there a difference in build between old vs. newer platters?)
I've played with them, but I can't remember testing their hardness in any way.
Zero - are you planning on testing them further?
Best, and Happy New Year!
Dave
If some of these singal mirrors admit they don't have the reflective quality of a true mirror (and have a star hole in the middle), and the platters have much more reflectivity than a CD (plus a hole in the middle), I'm still curious as to how they would perform at distance and how they hold up in a pocket.
If the platters are simply oxide coated, I'd expect the coating to wear off (much like a CD) whilst in a pocket against shears and a flashlight. (Is there a difference in build between old vs. newer platters?)
I've played with them, but I can't remember testing their hardness in any way.
Zero - are you planning on testing them further?
Best, and Happy New Year!
Dave
I related experiences in utilizing CD's, which were ok on land, but I never checked them out in water. Off topic, eh, not really.
Anyway, I got a couple hacked out of the HD disc. So far they seem pretty tough. they are no where near being fragile and I had a hard time scuffing them up with anything other than sandpaper. I also did a less than scientific reflectivity test with a camera light meter. It read the same as a glass mirror. I admit its not an end all true test of operation or durability, but put up against the glass and polycarbonate mirrors I would say they would outlast them hands down.
Anyway, I got a couple hacked out of the HD disc. So far they seem pretty tough. they are no where near being fragile and I had a hard time scuffing them up with anything other than sandpaper. I also did a less than scientific reflectivity test with a camera light meter. It read the same as a glass mirror. I admit its not an end all true test of operation or durability, but put up against the glass and polycarbonate mirrors I would say they would outlast them hands down.
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