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Posted to rec.crafts.metalworking
Richard
 
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Default Cheap Chinese Mill-drill

On Tue, 29 Nov 2005 15:47:32 GMT, John Husvar
wrote:

Well, the boss finally broke down and bought a mill -- sorta.

It's from Cummins Tools, those guys who periodically descend on some
unsuspecting town and hold a "Truckload Tool Sale."

Ok, here's my 2 1/2 cents worth. Others have said, I agree, get an
el-cheapo set of R-8 collets, they'll save you a lot of headaches,
not to mention fingers or toes.

What none have said, check that thing out to make sure it's square, I
had the HF version, square didn't apply. First things to check:

Column square to table. Check front to back, It probably isn't, mine
wasn't. Not a big thing to deal with if you have a nearby shop with a
surface grinder available. The small bracket that mounts to the base
might need to have the bottom ground to make it square. Easy enough
with a right angle plate to fix on the surface grinder.

Second, is the spindle parallel to the column? Mine was also a
definite no. Easier to fix that it looks like, the head is made in
two halves, bolted together, complete with chips, burrs and raised
metal from the tapping. Straight edge and scraper make short work of
this, but when you reassemble, indicate it in any manner you can think
of. If the spindle is out of parallel, you're going to get errors and
not know where they came from

Pull the gib strips out and get the !$(%%*^ sharp corners filed back
so they're not digging into the corner of the gib, making adjustment a
joke and operation rough.

1" travel dial indicators with mag backs on them can make holding a
tolerance a lot easier, especially if the gib locks are set to just
drag a little. Work to the indicator, not the dials.

ER collets or end mill holders may seem like a good idea, BUT!
This is a small machine and the spindle isn't any too rigid to begin
with. Any amount of tool overhang you can eliminate won't hurt things
a bit. If you use a milling vise, don't bother with the swivel base,
it's just added height you've got subtracting from your already
limited space, it just makes things shaky.

Watch the oil, figure this is like most of the old machines, when the
oil quits dripping, it's time to add more.

It can be an excellent small machine, but a lot depends on the initial
setup, meaning make sure it's right before you scrap a bunch of stuff.

Rich