[Thinwater]

I am looking at a 1991 Mits DWC 90 H EDM Machine to cut the mag well of AR15 rifles. approx 3/4 x 2 x 2 1/2 out of 7075, the corners are to tight to mill that deep in less than 1 hr.

Is this machine any good? Parts available?

Thanks for any assistance.

JIM

[Othatvideo]

Will it handle it?...absolutely.

I ran a 90H that was bought new in 1988 until it died just last January. We moved it twice during it's life & it simply didn't like it. A wire "somewhere" in the controller shorted out on the rigging truck. After many hours of a technician at our plant?...we replaced it with a new machine.

The machine is solid structurally but limited in it's controller. In many ways I still miss that warbird. Non submersible which means dirtier than the newer machines but very dependable.

The surface finish that it provided with 2 skimcuts is virtually the same as a new Mits (with the high powered first skim) doing 3 skimcuts. The controller is limited in memory space. We ran macro intensive programs & thus we were constantly forced to have a revolving door loading & unloading programs into memory...we're a production shop that ran the same programs monthly.

While I loved this machine, I urge you to consider a new machine with more bells & whistles. It's a buyer's market.

I just cruised Ebay...there are a couple 'H' machines out there & I'll not dispute that $1600 for 2 used 'H' machines (1 working, the other for parts) is a great deal. But unless you already know Mits' of this generation or know someone who knows the same ...getting properly trained & etc. will get expensive quickly.

The controller is not PC based and thus will not understand a simple .nc (text) file. Your CAD package's DNC hookup will have to know how to talk to this machine. If you are not familiar with this...I suggest that you give MC Machinery in the Chicago office a jingle and talk about this. You can find their contact numbers at www.mitsubishi-world.com Their factory support is unsurpassed.

Again, great machine. But with it being a buyer's market...UNLESS you know the machine, I wouldn't go any older than an 'H1' generation. That's the dividing line between understanding a PC's text file...and having to deal with proprietory Mits language that's 20+ years old.

Best always,
-Brent