Electric Discharge Machine

EDM [MH20M]

BETSA® Motorized Electric Discharge Machine

The Motorized EDM [MH20M] has been designed to drill the tiny holes in any conductive gasket material required by the operation of Diamond Anvil Cells (DACs).

Electric Discharge Machine – BETSA®

Specifications

20 – 500 µmDrilling diameter
< 5 µmCentering accuracy
40 µm / minDrilling speed, Ø 200 µm in stainless steel
Any conductorStainless steel, rhenium…
× 200 / × 400Centering microscope
× 50 / × 100Observation microscope
12 kgWeight
19 × 33 × 42 cmWidth × depth × height

• Easy to operate

• Possibility to change the polarization and to tune both the voltage and the current: to optimize drilling performance as a function of gasket material, thickness and hole diameter.

• Motorized drilling: the voltage between the electrode and the gasket feeds back to control the movement of the vertical table.

Visualization during the drilling

No computer needed, and no camera software to update.

01 pre-drilling and alignment – BETSA®
01pre-drilling and alignment
02 drilling control top side – BETSA®
02drilling control top side
03 drilling control bottom side – BETSA®
03drilling control bottom side
04 Finished cylindrical hole — without red backlight – BETSA®
04Finished cylindrical hole — without red backlight
05 Finished cylindrical hole — with red backlight – BETSA®
05Finished cylindrical hole — with red backlight

Rotating head rotates 90 ° to change from centering visualization position to drilling

BETSA® abrasive tool [PONC01] for MH20M spark eroder electrodes
Sanding an MH20M electrode, video tutorial1:03Video tutorialSanding an MH20M electrodeWatch the video →

Abrasive tool for electrode used in MH20M spark eroder

Their deformation over time makes conical holes.

Our electrodes are easy to reposition and can be sanded with this tool to restore the electrical contact surface and the cylindrical shape of the hole.

– The tungsten top of the electrode is guided in a Ø500µm hole.

– The electrode is always perpendicular to the emery cloth.

– About 10 to 20 seconds to repair an electrode.

The abrasive tools have been designed to facilitate the repair (with emery cloth) of used and worn MH20M electrodes.

The quality of the repair does not depend on the dexterity of the user. There is no risk of destroying (folding or folding) the tungsten part of the electrode.

01 Sanded Electrode – BETSA®01 Sanded Electrode, tip close-up – BETSA®
01Sanded Electrode
02 Electrode after pre-drilling – BETSA®02 Electrode after pre-drilling, tip close-up – BETSA®
02Electrode after pre-drilling
03 Electrode after drilling – BETSA®03 Electrode after drilling, tip close-up – BETSA®
03Electrode after drilling
04 Electrode after several drillings – BETSA®
04Electrode after several drillings
Electric Discharge Machine – view 3 – BETSA®

ELECTRODES

from 60μm to 530μm by controlling the electrode voltage.

A needle is used for drilling from 10μm to 50μm.

Electrode Needle radius 2 to 5 µm.

Electrode Ø

Needle radius 2–5 µm50µm80µm100µm125µm150µm200µm250µm300µm380µm457µm500µm750µm

Never sand electrodes below 125 µm.

Built to last

Designed to be repaired, not replaced

The MH20M in the video left our workshop in Nangis in 1998. In 2026 its owner sent it back to us: servicing, cleaning, a board check, a spark adjustment — and it is drilling gaskets again, as precisely as on day one.

That is what we build for. There is no throwaway electronics inside an MH20M: every part is machined and assembled in-house, and the workshop that built it is the one that services it. A machine you can keep for decades is also the most economical one: one overhaul costs a fraction of a replacement, and it comes back up to date.

That is why we guarantee our machines for up to 10 years, and why we still service every MH20M we have ever delivered.

10 yearsGuarantee
28 yearsThis machine, still in service
1 overhaulBack up to date