machines which I have made, am making, or intend to make, and some other stuff. If you find this site interesting, please leave a comment. I read every comment and respond to most. n.b. There is a list of my first 800 posts in my post of 17 June 2021, titled "800 Posts"

Tag: seismic wave generator

Seismic Wave Generator

To continue the posts about making the seismic wave generator.  See the previous post about water jet cutting the steel plates.

From what I am told, the generator is positioned, pinned to the ground, and hit on the ends with a sledge hammer.    Instruments pick up and measure the seismic waves in order to analyse what is beneath.

Sound is not required.  In fact sound is annoying and a disadvantage.

The operator stands on the generator while swinging the hammer.

So here is the finished item, ready to be delivered.  It weighs 20kg.


Striker - 1.jpg

The seismic generator, ready to be delivered.  The brass plate is to remind the user to wear safety glasses, safety boots and ear protection.   The holes in the impact plates are to permit aluminium plates to be attached if the situation absolutely requires no sparks.


Striker - 3

There are 10 ground pins.  Each pin is slightly tapered to make removal from asphalt or clay easier.   The pins are machined from 16mm set screws.  I imagine that 6 or 8 pins will be adequate to hold the generator in most surfaces.   The pins are removed for transport of course.

It will be interesting to hear how it performs.






In these clips, 10mm thick steel is cut with a water jet machine.

As a first timer it was amazing to see.

The water is pumped through a tungsten carbide jet, under enormous pressure.  The water carries garnet dust, which does the actual cutting.

The steel is 10mm thick, but this machine will cut through 200mm thick steel!  It will cut wood, carpet, granite, marble, any metal, in fact any material except diamond and some glass.

The cut is accurate to within 0.1mm.  The kerf is 1mm.  The angle of divergence away from the vertical is approx 1 degree.

Click the arrow below to watch the 8 minute video.



Shear Wave Seismic Source

You are probably wondering WTF this is about.

So was I, when I was asked to consider making one.

I gather that researchers and geologists use them to work out what is going on in a geological sense underneath our feet.

Seismic waves are generated from ground level, and instruments pick up frequency changes and time delays, providing information about what is happening below.

The seismic wave generator has the following requirements…

  1. it is anchored or spiked to the ground surface

2.  the spikes must be able to penetrate all types of ground surfaces, including asphalt, and be removable from the ground, and from the device.

3. it must be transportable by hand i.e. no more than 20-25kg

4. it must withstand thousands of impacts from a sledge hammer, in 2 directions

5. it must be  durable, repairable and not too expensive

6. the user must be able to stand safely on the device, while swinging the sledge hammer

7.  it must not generate sparks in some situations

So I have been thinking about these requirements, and I have produced a plan which has been accepted by the client.

Photos of the project next post.