Talk:Electrical discharge machining

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Much of this article appears to be copied directly out of the following article: ... which is, furthermore, uncited!

That is inappropriate.

20:08, 13 July 2016 (UTC)


Thought folks might find these useful for inclusion either as resources or cut and paste or rephrase portions in the main article(s)?

Mgmirkin 19:48, 11 August 2006 (UTC)

Added the relevant links. I left the job shop link out as the others are far more thorough. Good stuff.I already forgot 21:37, 11 August 2006 (UTC)


Anyone care to go into detail on the actual physical mechanics of how EDM works? IE, the actual physical processes that enable EDM to work by increasing electrical stresses, super-heating and ejecting material from the surface, byproducts created (microscopic spherules), how the byproducts are flushed, how often, what happens if the byproducts aren't flushed, etc.

Seems like this would all be handy info for the article...? Anyone want to tackle it? I'm not sure I'm technical enough to trite the technical parts, though I have a pretty decent understanding of the processes involved. Not sure I can write it out sufficiently technically to do it justice. Mgmirkin 20:04, 5 November 2006 (UTC)

Proposed merge with spark erosion[edit]

Is there any difference between EDM and spark erosion? From the description of both (and my understanding of EDM), they seem to be different terms for the same process. --GargoyleMT 02:51, 1 February 2007 (UTC)

Spark erosion is how EDM works. Spark erosion occurs in other stuff, but that's not how the article is written. I support a merge. —The preceding unsigned comment was added by Toastydeath (talkcontribs) 06:21, 1 February 2007 (UTC).
My understanding is that EDM and spark erosion are basically two names for the same thing. I think that EDM is a more standard industry term, but they're fairly interchangeable. I support a merge/redirect into EDM. As the prior user commented, spark erosion is the process by which EDM works, IE lots of tiny tiny spark eroding a surface in an electrically active process. Basically, you get a dielectric fluid of some sort, then use either a machined template (die) or a wire to electrically erode or cut parts to be machined. As the objects get closer and the electric current is applied, tons of tiny sparks form between the objects, causing erosion. Slowly but surely, the unmachined form takes the inverted shape of the die that's being sunk toward/into it. Wire cut uses a wire rather than a a die, and can machine complex shapes that a die can't necessarily. Long story short. Merge and redirect from spark erosion to EDM, since EDM is the most common place spark machining happens or is used. Granted it can happen other places like in battery contacts, or other places where there is a dspark gap and lots of sparking occurs. Contacts can get eroded over time, etc. Still, it's mostly used in relation to EDM. Mgmirkin 23:50, 13 March 2007 (UTC)
I agree with Mgmirkin. Spark erosion is the process but it refers to the same thing. I am in support of a merge but there is information in the Spark Erosion that is not in the Electrical_Discharge_Machining article. 21:22, 17 March 2007 (UTC)
Done, but if someone wants to integrate Advantages and Disadvantages more, I'd appreciate it. --GargoyleMT 00:25, 13 July 2007 (UTC)
I would disagree with a merge on this article. I work for an EDM Sales company and while spark erosion is HOW Electrical Discharge Machining works, it doesn't encompass fully what Electrical Discharge Machining is. Merging the articles would, in my opinion cause an information loss for EDM. -- midnightbex 15:52, 20 March 2008 —Preceding unsigned comment added by (talk)

This action seems to have been already taken. Gjroyce (talk) 04:33, 28 September 2011 (UTC)

References, material removal mechanism, micro-edm[edit]

Dear All, I've just registred and this is the first time I write something on Wikipedia. Will be ok for you if I add/alter a bit the part regarding the mechanism of material removal in EDM? I have a few references about that. Especially, I found some controversy in the literature regarding the ability of thermal models of the removal phenomenon to explain what is going on between tool-electrode and workpiece-electrode in any possible machining condition and application. Also, is anyone interest in starting a micro-EDM article? Or should micro-EDM (whatever it is meant this that - Again, it is debated) be part of this article?

Best regards,

Cemaf (talk) 20:27, 11 April 2009 (UTC)

Welcome to Wikipedia! By all means be bold and improve the article, especially if you have some good references. As for micro-EDM'ing if you think there's enough info to warrant a new article then start a new article, otherwise just create a new section called "Mirco-EDM" and go from there. Wizard191 (talk) 21:27, 11 April 2009 (UTC)
Thank you very much for your warm welcome. I took the plunge and I modify the introduction, added two new sections and a few references. I think there is definitely enough material for a micro-EDM article, but it will be overwhelming for me to start something. Some of the the references that I've put are in that domain, mainly. Yesterday, after finishing with the article I had replayed to you, but something must have gone wrong because today I could not find in the discussion page what I had written. Perhaps I fail to save. So apologies if this answer reaches you after the article modifications and not together with. I'd like to ask you a courtesy. One of the references Ferri et al. is repeated and it shouldn't. I mean there should be just one entry in the list of references with several points where that reference is cited. Could you fix that for me please? I am still not very familiar with all the details of editing wikipedia pages. Overall, what do you think? Any idea on how improve on the article? My impression at the moment is that my modification of the intro resulted in a too long intro. Also the overall structure of the article could perhaps be improved. I look forward to hearing from you. Best regards Cemaf (talk) 09:43, 14 April 2009 (UTC)
Overall, your first edit looks great! I've gone in and fixed ref. It's pretty simple if you take a look at the code.
As for the layout, I agree that the introduction is too big. For a featured article, the guideline is that there shouldn't be a need for any referenced in the introduction, because its introducing material that will be cover in more depth in the article and also referenced in the body. So, I'd say if we can make it fit in an existing section or make a new section for it all, that would work much better. As for starting the micro-EDM article there are a couple of ways you can do it. You can start a micro-EDM section and populate it over time and if it get's big we can split it off. Otherwise you can just start the micro-EDM article and still work on it over time. These articles don't become perfect instantly. Even if you can just start a stub that's better than nothing. Wizard191 (talk) 00:53, 16 April 2009 (UTC)
Thank you very much for the amendments and the feedback. I saw how you did for the reference I mentioned and I hope not to bother anymore for this kind of matters. Regarding the part before the table of contents I think that perhaps the easiest way is to consider it as an abstract/synopsis/executive summary/overview and therefore write from green field a very few lines for it. Meanwhile, we could move the current part that is before the table of contents, immediately after and call it introduction. I'll do that sooner or later. In this way we can include some references also in such a section. Or am I wrong? But what about the remaining of the article? I think that it also needs some major re-thinking. In this re-thinking we could include as you suggested a few lines about micro-EDM, provisionally. Then if someone could start a dedicated article for it it will be linked to it. But how to structure the whole article? Any suggestion? Another question: would it be possible now to remove the box at the beginning of the article saying that there are no citations? It would make a reader less suspicious about the content. Best regards, Cemaf (talk) 10:34, 16 April 2009 (UTC).
I haven't actually read through all of your additions yet, so I'd have to sit down and read it to get a better feel for how to organize the sections. Just to note, Wikipedia doesn't use an "Introduction" section because the lead (the paragraphs before the table of contents) is the introduction. You can find more info on how Wikipedia lays out articles at WP:MOS (although its a very long and daunting page; its better to just use it as a reference when in question). If you want to see good layouts check out: die casting, forging, and extrusion. Wizard191 (talk) 17:40, 16 April 2009 (UTC)
Ok thank you. For the layout I'll give a look at the suggested links and then I'll try something. Best regards Cemaf (talk) 18:10, 16 April 2009 (UTC)
New shorter introduction added. A new structure to the overall article has been given. Yet, for me the introduction is still a bit too long. But it's difficult to leave out anything. Let's see if someone else has some interesting contribution to add or modify. Best regards,Cemaf (talk) 17:16, 19 April 2009 (UTC)

The history section self-contradicts.[edit]

Please fix this. Built in 1969 but invented in 1980? Please. -- (talk) 22:41, 28 October 2009 (UTC)

This has been resolved. Wizard191 (talk) 21:08, 2 November 2009 (UTC)

Quality C --> B: Howto?[edit]

Out of curiosity, what is most perceived as missing for promoting this article from Quality C to B? I've read the characteristics of C and those of B. To me it would be closer to B than C. Yet if it is in C they must have some reason. Any idea? Best regards,

Cemaf (talk) 21:44, 17 November 2009 (UTC)

It is a C because there are large swaths of unreferenced text. Wizard191 (talk) 21:53, 17 November 2009 (UTC)
I have inserted a few references more. If that were not enough, please, may someone let me know where the main areas of unreferenced text still are? I might try to give it a further go. Best regards, Cemaf (talk) 21:11, 18 November 2009 (UTC)
The "type", "application", and "advantages" sections are still completely unreferenced. Wizard191 (talk) 22:00, 18 November 2009 (UTC)
I have added a few more references. I have though a few comments. Perhaps I'll add a few more. I understand that the article can be significantly improved. Yet I have given a look at a few other class C articles. They don't seem to me as complete and as referenced as the EDM article at all. I don't understand the reason why the link to the freely-available and downloadable thesis in the history section has been removed. In that thesis there are a few sections about the history with also very interesting figures. What is wrong to put a pointer to it? If someone were interested, he could find there better information than I could possibly write and, most definetely, better information than the presently written in the history section. Why deprivating a reader of such an opportunity? So, please, if the reasoning above convinced you, could you please put in again the deleted link in that section. If it didn't, never mind. I won't re-insert what you removed to avoid starting discussions that would not lead anywhere. I have made some adjustments to the text while introducing some references. For instance removing the heat/vaporisation because there is a whole section dealing with this matters and because it is controversial in some application fields (as also stated in the dedicated section). Also, in the application section I have put a commercial link, just to prove that there are companies that use EDM for such specific application (prototyping). In this way the claim is substantiated/referenced by the existance of these companies themselves. In general, as for the claims made in those sections, it might be hard to avoid pointing to commercial organisations due to the nature of the claims and of the sections. Best regards, Cemaf (talk) 20:51, 19 November 2009 (UTC)
Usually referring to an outside source for additional information is frowned upon, which is why I removed it. My suggestions are to either incorporate the info into the article and use it as a real reference, or to list it in the external links section.
As for C class article, most articles fall under this category because they are bigger than start class articles but not well enough established or referenced to qualify for a B class. Wizard191 (talk) 21:50, 19 November 2009 (UTC)
Hello, pardon me for the non prompt answer. As far as I am concerned, you are more than welcome to read the history section (1.1.2., 4 pages, 3 figures) of the freely accessible cited document and to paraphrase it in the history section of the Wikipedia EDM article. Yet, you will miss the figures, unless, of course, you contact the author asking him permission to reproduce them.
Regarding the quality assessment, there are between 10 and 20 references here, so it must be because is not well enough established. I gave a look at other articles classed as C. Overall, I got the impression that there is a large variability among them. My impression is that EDM (but also other classed C) seems really closer to satisfy the 6 points of class B than the definition of class C. But never mind. Personally, what I think the article lack the most are figures, especially of the process/sparks. But they are not easy to get. Regards, Cemaf (talk) 19:26, 27 November 2009 (UTC)


I WANT CLEAR PICTUERE ABOUT "HOW TO RECHARGE EDM MACHINE? & WHICH MATERIAL IS USED IN THIS PROCESS?" — Preceding unsigned comment added by (talk) 06:14, 2 September 2011 (UTC)

What would you like to recharge? I've been asked many times if used Wire EDM electrode wire can be re-used and I have found no evidence this is possible. Every manufacturer of wire I've used will only make wire from virgin materials. Used wire has a heat affected zone and a layer of recast, much like the workpiece, so the chemical structure and composition of the wire is no longer uniform. The obstacles only multiply as you consider the difficulties in either refurbishing or purifying the used wire and re-drawing it (of which I know little about). The main thing to look at is that wire costs around $1-2USD per hour and it would take more than that to try to make the used wire into good wire again. I hope that's what you were asking and that it sheds some light on your question Gjroyce (talk) 04:33, 28 September 2011 (UTC)

Wire EDM Axis movements[edit]

I work with Wire EDM machines every day and I believe the following statement (found under the subsection Wire EDM is incorrect:

The upper guide can control axis movements in x–y–u–v–i–j–k–l–.

Furthermore, I believe that the entire second paragraph of this section fails to completely describe how the wire electrode is positioned around a workpiece, which is crucial to understanding the benefit of these machines.

I think it is more correct to re-write the second paragraph of the aforementioned subsection to more clearly state the information provided and also to add crucial information that is not present. Here is a list of key points I would cover. I will fetch my operator's manual for the late model Fanuc Wire EDMs in hopes that it will serve as an authoritative source for some of this information:

  • Physical planes
    • The machine guides the electrode wire from a spool of unused wire through two independent sets of guides and energizing contacts called "heads."
    • The lower head is below the workpiece and moves in a horizontal 2 dimensional plane where the axes are labeled "X" and "Y".
    • The upper head is above the workpiece and moves in a horizontal 2 dimensional plane where the axes are labeled "U" and "V".
    • The upper head can move perpendicularly between the XY and UV plane to adjust for workpieces of different thicknesses, to minimize the distance between guides, and to bring flushing closer to the top of the workpiece.
  • Motion (seems like a lot of this would be covered by CNC, but there seems to be little mention of actual movement after I skimmed through it)
    • CNC machines are much more prevalent (unsure where this citation can come from).
    • Usually, 5 axis Wire EDM machines can only move in straight lines, arcs, and, sometimes, full circles. 6th and 7th axis tables exist that can provide motion in additional axes, commonly rotational about the XZ or YZ planes.
    • Straight line XY and UV motions require only an endpoint.
    • Arc or circular XY and UV motions require an endpoint and also the location of the center of the radius, designated by "I" and "J" for the XY plane and "K" and "L" for the UV plane.
    • This combination of upper and lower plane movements can create anything from cylinders and boxes to complex 3d contours with constantly changing wire angles, for example, a shape with a square on top and a circle on the bottom.
  • Logical planes
    • The path that the heads must travel does not have to be the same as the resulting workpiece.
    • Instead of requiring the operator to interpolate between the desired result and the required position of the guides, programs can be written using a programming and thickness plane.
    • The programming plane is an arbitrary Z height parallel to the XY and UV axes to simplify programming.
    • The thickness plane is usually a signed distance from the program plane to another arbitrary Z height.
    • Setting these two logical heights to points at which the part schematic corresponds to the workpiece's orientation in the XY and UV planes is common.

I will try to solidify this into something more workable, but if someone has more time than I and can try to fix this issue, I would have no objections. This is my first contribution and I hope I've provided some useful insight. Gjroyce (talk) 04:33, 28 September 2011 (UTC)

Conficting statements of "first"[edit]

"In 1969 Agie launched the world's first numerically controlled (CNC) wire-cut EDM machine.[2][3] Seibu developed the first CNC wire EDM machine 1972 and the first system manufactured in Japan."

These claim the same "first" for two different companies. Can someone in the know straighten this out? Are they really talking about the same "first"? -- Dougher (talk) 13:02, 6 December 2012 (UTC)

I have replaced both these claims with history from an independant reliable source, Jameson. Jameson seems to deliberately avoid naming companies and his dates are not quite the same so I think the company names should be left out, at least until reliable sources are found. Part of the problem here is that there is a distinction to be made between NC (the Agie claim) and CNC (the Seibu claim) which Jameson explains but our article had conflated. Another problem is that these claims only relate to wire-cut machines, not EDM in general. Again Jameson makes a clear distinction between die-sink and wire-cut machines which our article mixes. I will add a die-sink sub-head to the history to clarify this. SpinningSpark 20:55, 6 December 2012 (UTC)

Typical parameters[edit]

I would like to see some examples of typical operating parameters:

  • Gap length
  • Voltage
  • Peak current
  • Charge
  • Pulse rate
  • Pulse energy
  • Travel speed

Comfr (talk) 19:19, 23 March 2016 (UTC)

Use in MEMS[edit]

Some sources such as this: talk about EDM being used in MEMS technologies. Perhaps this is worth dedicating a section to? This article as it stands seems to focus on macro-scale manufacturing. — Preceding unsigned comment added by TheUnnamedNewbie (talkcontribs) 10:20, 4 January 2018 (UTC)

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