Jump to content
  • The above Banner is a Sponsored Banner.

    Upgrade to Premium Membership to remove this Banner & All Google Ads. For full list of Premium Member benefits Click HERE.

  • Join The Silver Forum

    The Silver Forum is one of the largest and best loved silver and gold precious metals forums in the world, established since 2014. Join today for FREE! Browse the sponsor's topics (hidden to guests) for special deals and offers, check out the bargains in the members trade section and join in with our community reacting and commenting on topic posts. If you have any questions whatsoever about precious metals collecting and investing please join and start a topic and we will be here to help with our knowledge :) happy stacking/collecting. 13,000+ forum members.

New Testing Equipment: Landtek TM-8812C Ultrasonic Thickness Meter


Recommended Posts

I bought a new toy to play with, it's the Landtek TM-8812C ultrasonic thickness meter.   An ultrasonic thickness meter or gauge (UTM or UTG) is just another tool to help you detect fake silver or gold bars.  How does it work?   Basically a UTG tells you the thickness of the material in question.  You first measure the metal's thickness with a digital caliper.   Then you input the sound frequency of the metal in question into the meter and measure the metal with the probe.   The result that you get should be the thickness of the material measured.   If your test results are wildly off, then you know you have a fake.  If your test results are within acceptable variance, it is genuine.

 

The specs of this unit are:                                                             

measuring range: 1.2 ~ 200 mm (0.05 ~ 8 inches)

resolution: 0.01 mm

accuracy: +/- (0.5% + 0.1)

sound velocity: 500 ~ 9,990 m/s

 

UTG Pros:

- it can detect fake bars where other testing equipment says it's genuine (eg. XRF)

- reasonable cost to purchase, when compared to other testing equipment (eg. Sigma Metalytics Pro, XRF)

- works best on 999 purity gold and silver bars

- works best on flat surfaces like bars

 

UTG Cons:

- does not work on metals that are not pure (e.g. American gold eagles are 91.6% pure but contain other metals that can skew the results)

- requires direct contact of probe on the metal (cannot measure with capsule or plastic wrapping on)

- requires the use of a medium between probe and the metal, like glycerin or oil

- bars of different sizes will require probes of different frequencies for optimal testing results (edit: cannot confirm, more testing required)

- cannot use with numismatic coins, as the glycerin medium used for the probe may damage it.  Also the probe may scratch numismatic coin.

- does not work well with coins that have patterns or designs, may give inconsistent results

 

Celerity of common metals, including silver and gold.

Alphabetical   By Velocity of Sound
Metal Velocity of Sound
Aluminum 6,400 M/s
Brass 4,300-4,700 M/s
Copper 4,760 M/s
Gold 3,240 M/s
Iron 5,950 M/s
Cast Iron 4,600 M/s
Lead 2,160 M/s
Nickel 5,600 M/s
Platinum 3,300 M/s
Silver 3,650 M/s
Stainless Steel 5,790 M/s
Tin 3,300 M/s
Tungsten 5,200 M/s
Zinc 4,200 M/s
   
Metal Velocity of Sound
Lead 2,160 M/s
Gold 3,240 M/s
Tin 3,300 M/s
Platinum 3,300 M/s
Silver 3,650 M/s
Zinc 4,200 M/s
Brass 4,300-4,700 M/s
Cast Iron 4,600 M/s
Copper 4,760 M/s
Tungsten 5,200 M/s
Nickel 5,600 M/s
Stainless Steel 5,790 M/s
Iron 5,950 M/s
Aluminum 6,400 M/s

 

1.thumb.jpg.feaa2646496073ef3e1dc8bdd74579b3.jpg

11.thumb.jpg.3ab3f11aece1a13f5788cec1f400227c.jpg

12.thumb.jpg.aa6f4e010a85ff7b6a6bc6a2485eadea.jpg

 

 

 

Edited by SilverStorm
Link to post
Share on other sites

Using my 2021 1oz Canadian silver maple leaf as a test coin, I measured my SML with a digital caliper and got an approximate thickness of 3.07 mm.   I inputted the celerity of silver into the TM-8812C, which is 3,650 m/s.  After adding a drop of glycerin onto the SML, I get a measured thickness result of 2.73 mm.   This give a variance of 0.34 mm that is less than actual.   The results can be explained due to 2 possible reasons: first, the SML has patterns and does not have a smooth surface.   Secondly, the standard probe provided with the UTG may not be optimal for measuring precious metals.   As long as the variance is not large, the results is acceptable.   I hope this thread helps you to decide if a UTG is right for you.

Note: the SML test coin was checked twice to confirm authenticity.  Once with the local coin dealer who had the Royal Canadian Mint's Bullion DNA machine (coin was confirmed with RCM's online database); and secondly, with my Sigma Metalytics Pro Mini.   So I am 100% confident that the SML test coin is genuine.   Any testing discrepancies lie with the method of testing or the equipment itself.  And as was mentioned in my first post, the UTG is not recommended for coins (hence the results I obtained).   

 

7.thumb.jpg.cc22f74ddbd29ad70691a79a1d7ae36d.jpg

3.thumb.jpg.0aafe0a888f0ca41b9b3360ee1dd699d.jpg

5.thumb.jpg.c544b98a0a4719eb7f3e662378cb3a42.jpg

Edited by SilverStorm
Link to post
Share on other sites
10 hours ago, BiteSizeTrader said:

Where can you buy it from? 

I bought this directly from the manufacturer in China.   Here's the website link:

Ultrasonic Thickness Meter TM-8812 - Guangzhou Landtek Instruments Co.,LTD

Send email to: sales@landteknet.com

Attention: Ms. Annie Wu

 

Link to post
Share on other sites
10 hours ago, DrunkMonk said:

Is there no requirement to calibrate your equipment with a calibration block of the same material you are going to test.

Very small changes in velocity will give you false reading. 

There are a lot of variables with Ultrasonic inspection!

Yes, you indeed need to calibrate the UTG, the calibration cap is mounted to the side of the device.   I forgot to mention I calibrated the UTG before using.  Thanks for pointing that out though.

You are correct, there are a lot of variables to take into consideration.   I'm still learning, and I hope to have more insights I can share with all as I discover what a UTG can or can't do.   My next step will be testing some silver bars that are thicker.  However I am loathed to take the plastic wrapping off the one I have now (St Helena 250 g bars), as I prefer to keep them as mint as possible.   I'll make a decision one way or another soon enough.

Edited by SilverStorm
Link to post
Share on other sites
10 hours ago, SilverStorm said:

Yes, you indeed need to calibrate the UTG, the calibration cap is mounted to the side of the device.   I forgot to mention I calibrated the UTG before using.  Thanks for pointing that out though.

You are correct, there are a lot of variables to take into consideration.   I'm still learning, and I hope to have more insights I can share with all as I discover what a UTG can or can't do.   My next step will be testing some silver bars that are thicker.  However I am loathed to take the plastic wrapping off the one I have now (St Helena 250 g bars), as I prefer to keep them as mint as possible.   I'll make a decision one way or another soon enough.

I feel your pain unwrapping a silver bar! Most UT gels are water based so not the best applying it to your silver bar.

Do you know what frequency and crystal size the probe is?   

I do Ultrasonic testing on welds and metals, any questions you have just fire them over.  

TBH if I was testing silver or gold I would probably opt for PMI testing (positive material identification) only due to so many variables with UT. 

Link to post
Share on other sites
1 hour ago, DrunkMonk said:

I feel your pain unwrapping a silver bar! Most UT gels are water based so not the best applying it to your silver bar.

Do you know what frequency and crystal size the probe is?   

I do Ultrasonic testing on welds and metals, any questions you have just fire them over.  

TBH if I was testing silver or gold I would probably opt for PMI testing (positive material identification) only due to so many variables with UT. 

Wow you have experience with UTG?!?  You are a godsend!   😆

I will post up the specs tomorrow for you to look at.  Thanks DM!

Link to post
Share on other sites
1 hour ago, SilverStorm said:

Wow you have experience with UTG?!?  You are a godsend!   😆

I will post up the specs tomorrow for you to look at.  Thanks DM

1 hour ago, SilverStorm said:

Wow you have experience with UTG?!?  You are a godsend!   😆

I will post up the specs tomorrow for you to look at.  Thanks DM!

No problem look forward to it.

 DM is fine. 

 

Link to post
Share on other sites

Hi DrunkMonk, please see attached pdf file for the specifications.   The standard probe has a measuring range of 1.5 ~ 200 mm (for steel), diameter of Ф8 mm, and frequency of 5M Mz.   Other probe attachments that fit are shown on page 2 of the pdf file (probe technical parameters).

Any insights on proper usage, things to look out for, what to do (or not to do), etc is appreciated, and I thank you in advance for your help in this matter.  

 

 UltrasonicThicknessMeter_TM-8812_TM-8811_TM-8810_Catalog.pdf

Link to post
Share on other sites
16 hours ago, DrunkMonk said:

TBH if I was testing silver or gold I would probably opt for PMI testing (positive material identification) only due to so many variables with UT. 

Not familiar with the term "PMI testing" until I looked it up.   But I have heard about XRF though (just didn't know it relates to PMI...I do now!)

Two ways to do PMI testing:

1) XRF (equipment too expensive);

2) optical emission spectroscopy (OES), which I am not familiar with at all, but I'm assuming this equipment is going to very expensive as well.

 

 

Edited by SilverStorm
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Cookies & terms of service

We have placed cookies on your device to help make this website better. By continuing to use this site you consent to the use of cookies and to our Privacy Policy & Terms of Use