On 3 Jul 2004 17:18:00 -0700,
(Bill Ross) wrote:
I'm looking at machines for a home shop where I work on a wide variety
of projects. I can't decide which way to go:
1. Get a new Chinese mill (such as grizzly, harbor freight, etc...)
2. Get an old high-end mill (Bridgeport, etc...)
Assume the machines have very similar specs (in fact, the Chinese
machine may be a copy of the Bridgeport!). Assume also, that I
wouldn't be able to afford the better used machines out there.
Compare, for example:
http://www.grizzly.com/products/item...emNumber=G6760
http://cgi.ebay.com/ws/eBayISAPI.dll...m=3823642 872
These two machines both cost about $2,500.
The Griz has a power feed, the Bridgie doesn't.
Of course you can add a power feed to the Bridgie,
but that's extra $$$.
The Bridgie has a vari-speed head, the Griz doesn't.
Old vari-speeds can be trouble, and expensive to
repair, OTOH being limited to 5 speeds tends to suck,
especially since the Griz doesn't have back gears.
(That'd make boring and face milling problematic.)
The Bridgie requires 3 ph power, the Griz runs on household
AC. This has both pluses and minuses. You won't need a
rotary converter or VFD to run the Griz. OTOH, you can't use
a VFD to give the Griz vari-speed. You will need to budget for
a rotary converter or VFD to run the Bridgie in a home shop.
That need not be very expensive, but you have to have it.
The Bridgie has obvious rust, hopefully the Griz doesn't.
(Harold would have a fit, but the rust doesn't look too
bad in the pictures. It'd probably clean up ok.)
Between those two particular machines, I'd probably gamble
on the Bridgeport. However, you're really comparing apples
and oranges. The Griz you selected is a lightweight. A closer
Griz match to the Bridgie would be
http://www.grizzly.com/products/item...emNumber=G9903
Now you're closer to comparing apples with apples. Mass is
critical in a mill, more is better. No way a light mill can equal
a heavier one in terms of rigidity. Rigidity is the primary thing,
other than wear, that controls the ultimate precision and quality
of cut a mill is capable of producing. (Yes, now we're talking
about a $4,000 machine, but a Bridgeport was an $18,000
machine when it was new.)
In both cases, I would expect to spend a fair amount of work to get
the machine into good shape. The Chinese machine will come with a
variety of small problems and generally poor fit & finish -- it will
need a comprehensive overhaul out of the box. A low-price used
Bridgeport will probably also need a fair amount of work, maybe some
new parts, etc... and may be somewhat the worse for wear.
I wouldn't say the Chinese machine would require a comprehensive
overhaul. You will need to clean off the shipping grease, check for
casting sand, change the lubricant, maybe deburr a few edges, do
normal adjustments and setup, etc, but you shouldn't need to fabricate,
modify, or replace any parts. I have an ENCO mill similar to the larger
of the 2 Grizzly mills listed above. It took about 4 hours to get it ready
to work.
You know you're going to have to derust the Bridgie, maybe work
on the vari-speed ($$$), and if there is significant wear in critical
areas, returning it to like new precision is almost certainly going
to cost more than it is worth. (Not saying that's the case with the
particular machine you listed, but it could be.)
Are old mills on the market for $2,500 likely to be worn out? How
much is it going to cost to get them into good running shape? Once
it's tuned up, will the Chinese mill perform as well as the older
Bridgeport?
The light Chinese machine you chose is never going to match the
performance of a Bridgeport in good condition. OTOH the Griz model
I indicated probably would equal or surpass a used Bridgeport with
very minimal setup.
It is possible to find a Bridgie which has only had light use, and has
been well maintained. That would be a good machine to have. But it
is also possible to find one that's got serious and expensive problems.
You can't generalize too much about used equipment. Everything
depends on the exact details of the condition of the particular machine.
To answer your question, yes it is possible to get a used Bridgeport
in good condition for $2500 (sometimes less if you bypass dealers and
handle it as a private sale). The real question is, how can you be sure
the one you choose actually is in good condition? And what will it cost
to repair it if it isn't?
If you aren't intimately familiar with the machines, it'll probably pay to
hire a good independent Bridgeport tech to inspect any used machine
you might want to buy. He'll be able to spot problems that you'd probably
completely miss, and tell you whether it is worth the cost of repair.
Note that while Machinery Values offers a 30 day return privilege,
you'd still be stuck with the freight charges both ways, and these
machines are heavy, so that could be a fair sum of money. It'd
be better to get the machine checked up front before it is bought
and shipped. At least they say it can be inspected under power.
That's a good sign.
Gary