Electro discharge machining

[mingki]

Hi, I am trying build EDM machine by following this show.

http://www.youtube.com/watch?v=uUN4_-xp1Wc&feature=fvwrel

I wonder what type of solenoid is used in this tutorial.

 

[berkshire]

Mingki,
This solenoid is set to pull away on making electrical contact
The video uses a door bell buzzer solenoid.Any low voltage solenoid set up so as to energize and pull in on electrical contact, thereby breaking the connection, will work for this application. More sophisticated machines use capacitors to increase the intensity of the spark.
How are your burst discs coming?
B.E.

 

[mingki]

Hi, Berkshire,
Thank you for your advise. I appreciate it.
I haven't started the burst disc making project yet, because I could not have been able to think of the way to machining the groove on very thin alloy. For now, I am using 0.027mm thickness 316 stainless steel and monel, inconel.
My concern is that the mechanical characteristics(tensile, elongation, hardness etc) of those materials might changed due to the heat and mechanical force I apply to them while I am trying to make the performance uniformed burst disc(Currently I need to make 5pcs of burst disc).
I heard ECM was good becasue it does not apply heat to the materials but it is not usable when I use unconductive materials. So, I searched for EDM but EDM creates spark, right? I bet it must be creating high temperature to the material.
So.. I am kind of lost in my project...

 

[ornerynorsk]

There used to be a place called Industrial Arts Supply Co in Minneapolis that offered a hobby EDM for several hundred dollars. Don't know if they still have it.