B
Byron
Guest
goldpelican said:
What's the minimum weight/thickness that this can be used at?
I take it it won't work on coins.
tungsten filled 1 kilo gold bar discovered in UK
- Thread starter smokey
- Start date
What's the minimum weight/thickness that this can be used at?
I take it it won't work on coins.
Thickness of 150 micron rolled gold tungsten bars still could be outside of the maximum limit of the XRF and the minimum limit of the ultrasonic test.
Hit it with a thin nail cost you nothing and can not be fooled after density test like these expensive equipments.
Hit it with a thin nail cost you nothing and can not be fooled after density test like these expensive equipments.
projack said:
What do you mean by "minimum limit of the ultrasonic test" - are you saying a 150 micron gold coating over tungsten would defeat ultrasonic thickness testing?
Not defending the test, I'm still waiting for equipment to arrive (will be a few weeks).
goldpelican said:
I am not an expert on ultrasonic machine but look to me on the video the test result on the screen shows only if you have a homogeneous solid material. Bubbles and crack would show up exactly the same on different metals, regardless of the metal.
So if you are looking the screen 150 micron on the top wouldn't even show the first pixel with the gel on it.
eBay - need to see if it's any good first!!!
I think it would only be useful on bars, not coins.
I think it would only be useful on bars, not coins.
JamesG said:goldpelican said:
hi if its good let me know where you got one for $172 , as these xrf machines are not 100% and cost too much
The ultrasonic and XRF machines have different purpose. You can not replace one with the other.
The XRF machines analgizing the metal compositions about 100 microns deep.
The ultrasonic machines analysing the inner material designed to detect cracks and air bubbles.
This is crucial for safety in industrial application like bridges airline parts, but also for smaller parts.
The question is how close to the surface you can see with them?
If you read my post, this quote answers the question - ultrasonic will reveal gold plated material.
"The 1090 Flaw Detector allows you to look into the Bar for voids/defects as well as UT velocity which is determined the products elastic modulus i.e Tungsten Velocity is 5183-5460m/sec and Gold is 3,240m/sec. For example if you calibrate for Au then the testing Tungsten bar of the same thickness, the UT thickness would read approximately half the actual because of the speeding-up of the sound through the Tungsten."
"The 1090 Flaw Detector allows you to look into the Bar for voids/defects as well as UT velocity which is determined the products elastic modulus i.e Tungsten Velocity is 5183-5460m/sec and Gold is 3,240m/sec. For example if you calibrate for Au then the testing Tungsten bar of the same thickness, the UT thickness would read approximately half the actual because of the speeding-up of the sound through the Tungsten."
Just to clear it up - there's two types of ultrasonic testing - ultrasonic thickness testing, and ultrasound inspection.
Ultrasound is what GoldMoney did - this looks for internal inclusions, cavities and cracks.
The other sort is ultrasonic thickness testing - this measures the thickness of an item based on the expected velocity of sound - thick of it as a hobbit test - "there and back again". Basically a sonar ping to see how far away the opposite edge is. If the material isn't gold or silver, the calculated thickness will be grossly wrong.
Ultrasound is what GoldMoney did - this looks for internal inclusions, cavities and cracks.
The other sort is ultrasonic thickness testing - this measures the thickness of an item based on the expected velocity of sound - thick of it as a hobbit test - "there and back again". Basically a sonar ping to see how far away the opposite edge is. If the material isn't gold or silver, the calculated thickness will be grossly wrong.
projack said:
hehe nice, i got a old Patek Phillipe pocket watch i picked up a few years back at Camberwell market here in Melbourne it's a real beauty i should also look at this to find out if its real gold it definitely has the weight of gold not sure if you would even fake a pocket watch with all the gears.
goldpelican said:
Thanks, so I've used the wrong term in my blog post.
