GIP PLASMA™ Wire Testing Guide
Outlined below are suggestions when testing PLASMA™ Hybrid Coated EDM Wire...or any high performance product. These steps outlined below are a guide.
All applications are different. Results will vary. We invite customers to see what results they observe/notice.
1) Put the wire on and do nothing. The machine should sense the gap opening and show a modest increase due to the "coating".
2) Next increase the "on time". Let the machine stabilize. Decrease the "off time". Let the machine stabilize.
3) Repeat step two until the wire breaks. Then back off to the previous setting where it was stable.
4) Back off on the wire feed rate. Ex. If the wire was coming off the spool at 10 meters per minute through the gap, back off to 9 per minute and so on till the wire breaks. Then go back to the previous setting.
The idea is to push the wire to reveal all benefits.
Overall benefit: Ideally the customers will see an increase in cutting speed and less wire consumed.
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GIP PLASMA™ Hybrid EDM wire Testing program
Recent comments made by a well-recognized authority in the EDM industry, Mr. Adrian Mawby, questioned the section in the Testing Guide above in which we propose to increase “On time” to optimize a higher speed for PLASMA™ Hybrid coated wire.
To further investigate this, we reached out to others in the industry to get their opinions. It is clear there are various opinions, some dramatically different, depending upon the individual desire to comply with established traditions or to push the envelope to develop their own technology.
GIP would like to share some of these opinions/comments regarding wire testing
Roger Kern, ITP technology EDM Today
“Adrian is absolutely correct.....I only adjust off time, servo voltage, corner protection and wire protection parameters to increase speed without having a material effect on the workpiece properties”
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Ron Baily, machine operator GIP customer
“.....is only partly correct if you don’t play all settings you won’t get max speed and COULD get too much over burn because servo isn’t pushing hard enough but not likely and if you do then first skim will probably fly and leave too much for second skim and slow it down”.
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Brad Hansford GIP technical advisor
“There are really good answers here. Mr. Chen’s pretty in depth and just. My reasonings and statements are based on years of being an EDM operator (machine operator). I have run many EDM machines (brands, sinker’s, wire’s and driller’s). The main questions/tasks given to operators is “how can we do it faster?” EDM’s have evolved over time as well as the types of “electrodes” (for any of the types). The OEM’s have usually done a really good job of creating technology for their machines, sometimes with a specific “electrode”. It doesn’t mean that the machine is limited to that technology. Most, if not all, can be optimized to do better, margin of gain varies from machine to machine. If putting a new electrode on a machine and getting a small gain without changing any technology that’s a good improvement. If knowledge, training and education have been obtained by the operator then the gains can be furthered without having to have the OEM create technology for you. There is the quickest and easiest way of just giving it a little more ON time, bonus, a bit more gain without having to change anything else. If the “electrode” can handle more energy, great, but that comes with everything that goes with it. Overburn, ok then offsets need to be adjusted accordingly. If you are only roughing, it’s pretty easy to adjust. Roughing and finishing, a little more detailed but an experienced operator or technical support person can make this much easier to do. This is true in all of the tool industry when it comes to cutting metal and new developments... the same yesterday isn’t the same as today.”
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Jeff Summer technical supervisor General Electric
“He is correct increasing on time creates more heat which will increase speed but will make the cut oversized and use more wire.... on time and peak amps are what creates the heat for the burn there is a fine line there before it’s too hot....he needs to try to increase servo speed and on time and amps but not to the point of affecting his recast layer so not to create more cracks.... that will be as fast as he can go unless he has a Hugh tolerance on his recast layers then just turn up amps”.
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Mr. Jack Chen Yoin
“In order to hold tolerance the same as brass wire in standard setup , customer adjusted the offset designed for this in the rough cut and surface finish after 3 skim cuts , it can reach 0.17 um RA much better than brass wire . We believe it is worth to spend a little time to tweak the parameters and save them in your machine technology page only in the first time using electronic EDM wire , after all it gives back to you the double speed and save tremendous amount of time .
If only increase “On time” and decrease Off time, it is not really enough and accurate as when the “On time” increased too much, it will burn too long and work piece size might change and if the coating is not designed to enhance surface quality, the surface finish would be poor under too much “On time” value. For that being said , if the increased percentage of speed is only 20% , then only adjust on time and off time parameters can be sufficient since before On time reaching the level would change the work piece size, the wire will break itself already “
“increase on time is not the perfect way but it is a good alternative . In order to reach faster speed , you must burn with higher current ( Amperage ) , the machines like Agie Charmillies, Makino, Seibu , they have parameter can increase the Amperage alone , machines like Accutex, Excetek , they do not have parameter to increase the Amperage alone , but through increasing the On time parameter value, you can reach higher amperage eventually since Time and amperage relate directly proportional .
One of our Customer increased On time from 19 to 24 , and adjusted the SV ( gap ) , wire feeding rate ( increased from 8 to 10 meters per minute , in Taiwan companies normally running 6 to 7 meters per minute to save wire ) as well as SC ( the machine head follows work piece more sensitively which increases the speed ) and eventually cutting speed increased from 0.42mm to 1.11mm , and machining time for one part reduced from 10 H to 4.5H .
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