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Vernon[_2_] Vernon[_2_] is offline
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Default Electric motor on KBC mill

On Sep 30, 11:33*pm, "DoN. Nichols" wrote:
On 2008-10-01, Vernon wrote:

On Sep 30, 6:47*pm, David Lesher wrote:
"DoN. Nichols" writes:


* * * * [ ... discussion over whether this was too much information
* * * * * * * * snipped ... ]

Gentlemen,


Swamp away. *I may not understand it. But I want it. *All of it. *I am
a very studious fellow. *Sort of like a python swallowing a large
meal. *It may take a while but I'll get there...


* * * * Good approach.

Here's the critter I bought:


http://www.driveswarehouse.com/Drive...ess+Vector+VFD...


* * * * That one looks nice. *One thing which you should consider,
however, is where the metal chips will fly from your tools. *Set it up
so they won't get into those louvers in the sides, because it can get
exciting if they reach the circuitry. :-)

* * * * Simplest thing would be a wood frame around it with window
screening all around it, and some easy way to get inside if you need to
use the front panel controls. *This should keep the chips out, and let
air flow through to cool it.

* * * * If you're going to add a braking resistor (if you decide that
you *need* instant reverse), you want it to mount to metal, not wood, to
avoid fire. *In use those can get fairly hot.

I think I've figured out that both types of converter are in my
future. *The VFD shipped today. *It should get the bench mill running.


* * * * O.K.

Today I began taking inventory of some of the other 3 phase stuff I've
bought over the years. *What happened was this. *There was a time I
thought that getting 3 phase service to me was imminent. *Then the
electric company threw me a curve ball. *That's why I happen to have
this stuff.


* * * * I understand.

Among the items gathering dust is a Delta Unisaw (table saw). *It has
a 7.5 HP motor. *The freebie plenum box has a 7.5 HP motor.


* * * * O.K. *A bit marginal, and you may have to take the time to tune
it to make it start the saw reliably. *And you want the saw located as
far from the mill (and other machine tools) as possible. *Sawdust from
some woods is acidic and can cause rust where you don't want it.

Although I'm told it's good to have an idler motor that's a little
bigger than the load I hope to be able to roll my own rotary phase
converter from the motor in the plenum box.


* * * * Yes. *If you turn out to need a little more capability to start
the saw, hang another three phase motor on the RPC, start it after the
RPC is started, and it will help to start the saw.

* * * * * * * * * * * * * * * * * * * * * * *I will make the most
rudimentary thing possible.


* * * * That may or may not be sufficient for starting the saw. *Try it,
and if you have problems, add tuning and then an extra idler motor.

* * * * * * * * * * * * * * *Once I've determined that both motors run
I will attempt to finesse the thing into something more
sophisticated.


* * * * O.K. *You can probably test the idler motor (perhaps with the
fan removed) by driving it from the VFD.

* * * * * * * * It should help to have the mill up and running so that
I can make stuff for the project. *Of course I make that statement
pretending I have a clue about lathes and mills. *But I don't.


* * * * Hey -- I find that having a project in mind while learning a
tool (or a computer program) makes it easier to learn more and faster,
because you have something to hang what you read on. *Later, re-read wit
another project in mind, and you will pick up other things.

Nevertheless, I do have a modest library of books on the subject.
I've been mining ebay for years for old books that pre-date the
computer age. *At least several of these are encyclopedic manuals on
machining.


* * * * Great!

Here's a more basic question for your collective wisdom. *Where to
mount the mill? *I have a very heavy duty table that came as a base
for a Diacro single station hole punch. *The foot print of the table
is just a tad wider than the mill base. *But the base is just a tad
longer (1") than the table.


* * * * Hmm ... bolt some steel or thick aluminum plate to the table,
and then bolt the mill to that so it is supported at all sides.

Notwithstanding that the table is strong enough I'm worried about the
high center of gravity. *If I bolt the table to the floor and the mill
to the table does that sound like a suitable arrangement?


Or should the mill be on a big heavy, long table?


* * * * How far does the table crank from side to side? *Is this the
green mill-drill which showed up in another thread? *I sometimes can't
keep the threads tied together.

* * * * Anyway -- since long workpieces are likely to be overhanging one
or the other end of the X-axis of the table, you want something to keep
it from toppling sideways. *I would suggest getting steel tube
(rectangular or square) which extends say 18" to either side of the legs
on the table, and bolting it to both the front and rear legs so it will
prevent tipping. *If you have to bolt it a bit above the floor to clear
the existing table's feet, add adjustable feet on the ends which you can
crank down to contact the floor. *You probably won't have a load out to
the front of the mill which is enough to be a problem, so you don't need
extensions to the front and back which you could easily trip over.
Probably a good idea to paint them a bright yellow/orange so you see
them. :-)

Then there's tooling. *I hope to buy some kind of lot assortment on
ebay. *I looked tonight. *A couple of guys are selling it saying
they're retiring. *Of course I still don't know an end mill from a
collet.


* * * * You will learn -- and this approach, while it might not give you
everything you need, will get you started.

Tomorrow morning we're off to Wichita Falls to fetch the lathe.


* * * * Good Luck,
* * * * * * * * DoN.

--
*Email: * * | Voice (all times): (703) 938-4564
* * * * (too) near Washington D.C. |http://www.d-and-d.com/dnichols/DoN.html
* * * * * *--- Black Holes are where God is dividing by zero ---


" If you're going to add a braking resistor (if you decide that
you *need* instant reverse), you want it to mount to metal, not wood,
to
avoid fire. In use those can get fairly hot. "

Hey Don,

According to the on-line owner's manual for this and other Hitachi
VFDs, if I understood it correctly, they already have a programmable
instant reverse circuit. That section of the manual went pretty much
over my head. But at least the node is there. Apparently they
recommend you "try it" and if it's not fast enough recommend adding
another resistor.

Indeed, I did start two threads. One for the mill drill and the other
for the lathe / mill. I myself forget which one I'm in. But the mill
is a KBC brand. It is an old model Grip-16 visible on the
kbctools.com website under "mills". Takes an R8 collet. Oddly, mine
is painted "grizzly green". THe KBC guy stridently denied any
connection between KBC and Grizzly. The new ones, as seen in the KBC
catalog are a different color scheme.

The foot print of the mill is approximately 16" x 24". The narrow
dimension is the width. The Diacro punch press table I have is just a
little wider than the base of the mill. But the mill is a tad longer
front to back than. Nevertheless, both the base of the mill and the
feet of the table are drilled to something like 1/2". The point about
the table and work overhanging is a good one and well taken.

The tech support guy for the VFD seller tells me that lots of people
install the drives in the cabinet beneath the mill. I intend to duly
consider this. But I am definitely concerned about burs, chips and
dross falling into the innards. Of all the 3 phase albatrosses I have
around the one I'd most like to get going after the mill is a 48"
bandsaw. Following that I have an antique Lincoln 3 phase welder. It
is a DC generator welder spun by a 3 phase motor at the base. Looks
like a fire hydrant on wheels. Probably built in about 1943 or
something like that. I've been unable to discern the horsepower as
yet.

Thanks for everything.

V