I looked at Romi link, noticed it only has 495 pounds of Z axis thrust? Its the spooky thing about smaller machines. RW milltronics has 2,000 z axis for reference. Be careful around "slippery machine tool salesman" has been my experiance. Local dealer for what ever brand; can make ALL the diffference on what to buy. where abouts are you?

You can also rig a static phase convertor to a 3 phase Y wound motor to generate 3 phase electrcity although you have to hear it run all the time if in same room. The plain static type box convertors only trick a 3 phase mottor into running so you lose one third power and can't reverse "quickly for reverse tapping"... I would investigate the electric power issue for what is best for you including if you move into a bigger "plant" later.

"for your garage" , I would also consider a Milltronics as some can come with single phase. They have a ridgid way machine with toolchanger and fill enclosure. mid 30's. I have a lathe and a machining center that brand, My landlord (for shop) has 6 m-centers, 4 cnc mills, and 1 cnc lathe that brand. you get what you pay for...to a degree. They have a web site with pricing and specs, some USA made. Good luck!

Dog eat Dog out there....

W.W. Grainger has some tech spec. pages in their catalogs in regards to filters,dryer layout, etc. I have seen some small cheap air compressors run all the time in small shops (almost industructable) I have a 80gal. tank ingersal rand 7.5 H.P cost about 1,100 10 years ago , just now getting ready to add dryer(w.w. Grainger)because I bought a Moore Jig-grinder. Blew air from fans on compressor to reduce moisture up to this point(when used jig grind head in jig bore) I personally would not overspend on an air-compressor but would look 5 years into the future. You can add-on smaller compressors in the future, etc and build up as you go if $$$ is an issue.

You must be using a horizontal milling machine with an arbor? Yup figure for the largest dia. one ( in some sense the weakest link, so you don't burn the rest up))

there are always some "morons" that will try and get away with murder and ruin privledges for everyone...nip that stuff in the bud with clear rules.

Lower RPM will give smaller hole, higher RPM will cut bigger as a general trend. I would run that part at 250 RPM and 8 IPM and liberal cutting oil....(reamers have more cutting edges than a drill)

If you are young develop the attitude of "pay me what I am worth, no more no less". You will probably learn more if you move around some and there is some stress and excitement to moving...I started in the trade at minimum wage and after I got older and had moved several times and started a small shop I asked the first shop owner wasn't I underpaid when I worked there??...His answer "you never complained" Good luck and learn to push yourself to excell.. end of sermon

I had heard some coolants (mainly all synthetic) can devour the plastic and rubber products-seals, electric cables,chip wipers etc.

Whwn all else fails try asking your customer what it is ..

yup you can overflush, plus I heard an old moldmaker complain "something is wrong with the edm machine" he had so much flush pressure it was deflecting the electrode when it went down into the cavity)one little 10-32 screw holding it..too much booze!

Not really what you asked for but 2 things that helped me the most when I was younger and learning to run a manual sinker in a mold shop were. 1) use a AM radio to amplify burning sound to hear it burn better and shop owner told me the secret to faster burning is flush,flush,flush.

I would definately finish after heat treat, over the years I have seen "everything" happen in heat treat i.e. shrink one time, grow next time,shrink one direction and grow the other on bigger mold cavity blocks(rectangle)....

I also read in last months trade publication about a mold shop on east coast that puts thousands of holes in molds for semi-conductor industry (incredible small and accurate almost unbelievable) manufacturing engineering or modern machine shop or the edm magazine EDM Today?? I am 75% sure it was a Makino sinker with something called the small hole attachment option. wish I could remember more, really small holes,seemed impossibal, one block had 7,000 holes...

My skill level in programming is "learning" but I designed an extrusion die couple years ago and had "twisted surface problem" I believe it was a chaining (where I clicked) problem. My reseller Fastec came to my rescue. wish I could remember more...

6,000 holes....I would make up test block and compare various processes..and not get trapped. I have seen some amazingly good finishes with LATE model wire EDM,and if that finish is not quite good emough, maybe try lapping with DIAMOND compound from like J & L or MSC,etc. Sometimes with reamers you can have some "rings" to polish out...(I have hand polished out tapered sprue gates by hand) Do NOT trap yourself with 6,000 holes and a bad process. my 2 cents worth..test,test,test

My understanding has been color codes are internal at the mill and steel wharehouses and can very, nothing much worse than machining a job and finding out from heat treater its not what we thought it was.

" thats a brand name of cast iron I think, from years ago when I wuz a kid. Cast iron is abrasive on ways , and think it rusts up machine "quicker" if left on table top at nite.

Mastering a Cam system is a major career acomplishment that takes time and "determination"...too often that may be left out...

"Dirty weld" was what my boss that owned the mold shop (and did most of repair welding) had said. I assume this was referring to being more prone to pits in the high polish)cavity area. Was taught A-2 high abrasion resistance, good welding repair, but more prone to crack. H-13 excellent weld for repair, very resistant to cracking, more prone to gall in pass core (shut-offs) etc( for picking steels , pluses and minus compared to each other. (some mold shops make everything out of H-13 and don't worry about it.This shop offered warrenties on thier molds so they enginnerred their steel, so this was based on their obsevations...

I was taught S7 is a shock resistant tool steel and we used it for pass core details in molds that we were worried may be prone to crack..good abrasion resistance, but a "dirty welding" tool steel for mold repair...

I am with Murlin, "I would add", make several at the same time in case you blow one, since they are simple shapes, to save time you can put them on magnetic parrallels to save grinding entire chuck, we hold 50 mill and we are nothing special, using standard Harig grinder. Watch the heat....linear coeffcient of expansion

I am a sound and feel toolmaker....can not help you with speeds and feeds....it cuts more like tough tool steel than the "aluminum" in the name.

I think alum. bronze is what ampco 18 and more brittle ampco 21 is... used in high wear areas ( like lifters in molds I have made were 21) and used for gibs and wear plates. I would recommend USA made HS Cobalt drills and "cobalt"end mills that are "brand new never touched steel" . I use usa generic out of J&L, MSC, etc. for face milling I use carbide inserts with lots of positive rake...sharp, sharp,sharp tools. ampco 21 is brittle and is more prone to chip out.