sink edm carbide

[ktd]

I am new to sink edm. What I want to do is burn around a contour in a piece of C10 carbide. My question is what works better a copper electrode or graphite? I have an old Sodick A3CR Mark VIII. I do not have conditions for Graphite to Carbide only Copper to Carbide. If any one could help it would be greatly appreciated.

 

Thanks,

[edmBosto]

Graphite will need many, many redresses on the electrode.

Copper in much better.

Copper impregnated graphite will also work.

Copper tungsten may be the best.

 

I only make electrodes, and I don't use them, but copper is a great way to go.

 

I think you need to burn with negative polarity?

HTH

[Lars Christensen]

edmbosto, is right on.

Copper tungsten is the way to go, and you want to reverse polarity.

[Kannon]

I third that...Copper tungsten is the way to go...I only use impregnated graphite if it requires very fine detail and is tiny... if I have to use a .01 ball endmill its going in graphite.

yep negative polarity also..

 

make sure your coolant is well above the workpiece...cause if its doing any roughing...it will dim the lights.

[ktd]

Thanks guys I will give it a try.

[JBowman]

kdt,

 

We use CuW on our old MK XI and the conditions might be similar to what you need listed below.

 

"( ON OFF MA IP SV UP DN LN STEP PL V HP PP C S L;"

"( CuW - WC(G2) WEAR CONDITION A,B );"

"C700 = 001 034 03 0010 04 02 03 001 0000 - 02 000 10 01 04 05;"

"C710 = 001 034 03 0020 04 02 03 001 0000 - 02 000 10 02 04 05;"

"C720 = 002 034 03 0030 03 02 03 001 0000 - 02 000 10 03 04 05;"

"C730 = 002 034 02 0050 03 02 05 001 0010 - 02 000 10 04 04 05;"

"C740 = 003 034 02 0070 03 02 04 001 0000 - 02 000 10 05 04 06;"

"C750 = 003 035 02 0100 03 02 05 001 0000 - 02 000 10 06 04 06;"

"C760 = 003 035 02 0120 03 02 06 001 0000 - 02 000 10 06 04 05;"

"C770 = 003 035 02 0150 03 02 06 001 0000 - 02 000 10 07 04 05;"

"C780 = 004 035 02 0230 03 02 00 001 0000 - 02 000 10 08 04 05;"

"C790 = 004 035 02 0310 03 02 00 001 0000 - 02 000 10 08 04 05;"

";"

";"

"-------------------------------------------------------------------;"

" COND. O.B. ON IP VDI./.RMS./.RMAX ;"

"-------------------------------------------------------------------;"

" C790 .0048 4 31 30 100 15 ;"

"...................................................................;"

" C780 .0037 4 23 29 89 14 ;"

"...................................................................;"

" C760 .0028 3 12 27 70 11 ;"

"...................................................................;"

" C740 .0018 3 07 25 56 9 ;"

"...................................................................;"

" C720 .0012 2 03 22 39 6 ;"

"...................................................................;"

" C710 .0009 1 02 20 31 5 ;"

"...................................................................;"

" C700 .0006 1 01 18 25 4 ;"

"...................................................................;"

" C972 .0004 1 00 16 20 3 ;"

"...................................................................;"

" C903 .0002 1 00 6 6 1 ;"

"-------------------------------------------------------------------;"

[ktd]

That seemed to work. I didn't have any copper tungsten so I just used Tellurium copper. It was very slow going. Is there any edm books that anyone can recomend on the edm process.

 

Thanks,

[JBowman]

You might want to go here for info on older Sodicks. They have it disabled for posting but you can still get manuals and other info.

 

http://www.sodick.com/forum/index.php

[Sandybar]

Reverse the polarity if using graphite!!!