Too cheap of a mill for slots?

[ericm979]

The Cincinati is a 3ph but you can get electronic phase converters. Good ones also let you adjust the speed electronically, so there's less fussing with belts. (if it's a belt drive like my RF30 is and the Cincinati appears to be). Many people buy a 3ph motor on purpose so they can get the speed adjustment from a phase converter.

If you can find a basic machining class at the local JC or similar, take it.

jmc is right on about mill/drill vs a real knee mill. OTOH my used mill drill was cheap and fits in my crowded garage. There are a lot of square column mill drills now that let you move the head without losing position. Some units have long quill travel which reduces the need to move the head though possibly at the cost of some accuracy when close to full extension.

 

[Fallon]

The Cincinati is a 3ph but you can get electronic phase converters. Good ones also let you adjust the speed electronically, so there's less fussing with belts. (if it's a belt drive like my RF30 is and the Cincinati appears to be). Many people buy a 3ph motor on purpose so they can get the speed adjustment from a phase converter.

If you can find a basic machining class at the local JC or similar, take it.

jmc is right on about mill/drill vs a real knee mill. OTOH my used mill drill was cheap and fits in my crowded garage. There are a lot of square column mill drills now that let you move the head without losing position. Some units have long quill travel which reduces the need to move the head though possibly at the cost of some accuracy when close to full extension.

A VFD (variable frequency drive) in the 1hp range starts at $200ish for a cheap one without a housing, 7hp is around $700ish. They arent rocket science to wire up, but will take a decent bit of time to learn & do correctly. They are all variable as its trivial to drive the silicon doing the work at different speeds via software.

You can use a single phase motor to spin a 3 phase motor & make your own rotary phase converter. The motors needs to be a decent bit more than your expected load though. It's not the cheap or best way to do things these days unless you have the motors already. A VFD will be cheaper, especially for only a couple HP, not to mention variable.

 

[metalbender]

The fancy electronics on my Grizzly went south. Not a lot of help from them on repair diagnosis. Went with a three ph motor and a VFD to keep the variable aspects of the mill. Run it on 220, does great. Will likely do the same for the lathe, giving better speed control.

 

[Kyle_in_Tex]

A good old Bridgeport type mill is hard to beat. Like that Exacto. That's a steal if it's in good shape and a legitimate ad.

Tooling is $$$

A friend asked me how much to drill some 1" diameter holes thru steel. I said at least $150, since the drill costs over $60

1" Drill, 118deg Point, High Speed Steel 474 - MSC

 

[Big Barn]

My two bits worth. Stay away from the round column mill drills, period. Been down that road, she's a bumpy one. The ideal would surely be a BP or clone, but reality sets in and unless there is an abundance of metal shops around for used used equipment, not going to find one. Mine is a square column Grizzly bench model. Fairly heavy, around 700 lbs, will do most jobs. And yes, the tooling quickly doubles the mill purchase price. Once set up, worth every penny though. Need to fix or build something, no problem. Lathes make square things round, mills make round things square.

I agree. I’ve had my square column mill drill for twenty years.

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A few years back I picked up this BP clone for well under $1000.

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Don’t be afraid of paying a little more for a decent machine that includes tooling. Buying pieces individually can easily outweigh the price of a used machine.

 

[Big Barn]

A good old Bridgeport type mill is hard to beat. Like that Exacto. That's a steal if it's in good shape and a legitimate ad.

Tooling is $$$

A friend asked me how much to drill some 1" diameter holes thru steel. I said at least $150, since the drill costs over $60

1" Drill, 118deg Point, High Speed Steel 98474 - MSC

Kyle depending on your depth of cut these sheet metal type cutters would do a cleaner cut and way faster for comparable price. And no pilot hole to drill.

 

[al3]

What do you need to accomplish? Or maybe what do you want to accomplish. Mentioned you weren't happy with a job someone did, that implies you have some standards in mind. You looking for a specific plus/minus tolerance across a certain length/depth? Quality of finish? Want to tap holes?

Answer to the above may help you decide if the mill/drill category will work. Tables are only so large, depth and length limited. Table feeds are unusual and expensive add on; sometimes a nice to have but other times essential if you are chasing a certain finish. As mentioned, Morris Taper tooling isn't as common as round with an R8 collet. Woring in the Z axis using a quill isn't terrible fast and certainly opens the door to error, but if you take the time to lock things down it can be done.

Also consider cost, space, power. The full size knee mills (Bridgeports etc, if you will) are great---they also take up space, are heavy (top heavy) and generally are 220 3 phase. An appropriately sized phase converter can approach the cost of a used mill/drill. Got a 220 30amp outlet available or going to have to hire that out? Moving/transporting/placing a full size Bridgeport can be pretty pricy. And while it is possible to get a mill/drill up and down a set of basement steps, that isn't possible with a knee mill. The need to rebuild/replace sacked-out ways is not uncommon on heavily used equipment

Towards the end of a 2 year machining program at a community college, I was offered a well used, round, single phase grisly mill drill. With the proper technique (no climb milling, correct speeds and feeds) it would keep a .003 Tolerance across 6 inches--adequate for a lot of the spacers, brackets and doo dads I needed to make. It was 1/18th the price of the new full size knee mill it was replaced with.

As someone else mentioned, the machine is just the beginning of the investment. Tooling (cutters, face/end mills), holders (vice, clamps), coolant and precision measuring equipment will all drain your pocket book. And once you invest, its nice to have a heated year round heated place to put it. If not coolant becomes a liability and condensation an enemy
.
Good luck. I thoroughly enjoy my metal working equipment. Will never break even. Getting some trade/tech school (Fox Valley) training would jump start the road to success.

 

[ArlyA]

The machine hat Cord is looking at, certainly isn't fancy, but I do wish I had it in my little shop......