<p><strong>General guidelines by material:</strong></p>

<p><strong>P20 (1.2311) - Pre-hardened mold steel</strong></p>
<ul>
<li>Roughing current: 6-12A</li>
<li>Finishing current: 1-3A</li>
<li>On-time: 100-300 microseconds</li>
<li>Typical MRR: 25-40 mm3/min</li>
<li>Notes: Easy to EDM, moderate electrode wear</li>
</ul>

<p><strong>H13 (1.2344) - Hot work tool steel</strong></p>
<ul>
<li>Roughing current: 8-15A</li>
<li>Finishing current: 2-4A</li>
<li>On-time: 80-200 microseconds</li>
<li>Typical MRR: 20-30 mm3/min</li>
<li>Notes: Higher wear on electrode, use copper-tungsten for finishing</li>
</ul>

<p><strong>S7 - Shock-resistant tool steel</strong></p>
<ul>
<li>Roughing current: 6-10A</li>
<li>Finishing current: 1-2A</li>
<li>On-time: 50-150 microseconds</li>
<li>Typical MRR: 15-25 mm3/min</li>
<li>Notes: Carbide precipitation risk if on-time too long</li>
</ul>

<p><strong>Stainless grades (420SS, 416SS)</strong></p>
<ul>
<li>Roughing current: 4-8A</li>
<li>Finishing current: 1-2A</li>
<li>On-time: 50-100 microseconds</li>
<li>Notes: Use positive polarity, expect 30 percent slower MRR</li>
</ul>

<p><strong>Electrode materials recommendation:</strong></p>
<ul>
<li>Graphite: Best for roughing P20 and H13</li>
<li>Copper: Better surface finish, preferred for fine details</li>
<li>Copper-tungsten: For difficult materials and thin ribs</li>
<li>Tellurium copper: Deep slots and fragile features</li>
</ul>

<p>Always run a test block before cutting production cavities. What EDM settings work best in your shop?</p>

<hr>
<p>你们厂里是怎么处理的？来评论区聊聊。</p>