I agree with Larry's comments.
Several manufacturers, including Makino, offered bolt-on EDM Drilling units like this in the 80's, and most have since discontinued offering them…with good reason.
While the concept of having an integrated EDM Drilling head on a Wire EDM is sound, the real-world practicality falls short in a few areas:
1) Price - the hard reality is that a bolt-on EDM Drilling Unit for a Wire EDM machine will be more expensive in today's world than a stand-alone EDM Drilling machine. Purchasing a dedicated EDM Drilling machine will also provide greater EDM Drilling capability (longer electrode length, tool change capability, etc.)...all at a lower cost!
2) Space / Unattended Machining Capability - The largest advantage of having a bolt-on EDM Drilling unit on a Wire EDM machine (even though they cost more than a stand-alone EDM Drilling machine) is for space-savings. There could also be a potential time savings with the ability to process the two different operations on one machine with a single setup (EDM Drill the start holes and Wire EDM in one setup), but most of the on-machine Wire EDM Drilling Units only support machining with a single reduced length electrode. Depending on how many holes that need to be drilled, the operator may have to "baby sit" the machine and manually exchange the EDM Drilling electrode before walking away and letting the Wire EDM portion of the operation run unattended.
3) Productivity - from a process and hourly machine run rate standpoint, it makes more sense to utilize separate machines for EDM Drilling and Wire EDM. This allows the Wire EDM machine to focus and maximize its operation on the more complex and higher value-added machining process that is Wire EDM. Does it make sense to use your Wire EDM time to EDM Drill the start holes?
- Brian