On Aug 31, 3:25 pm, Tim Wescott wrote:
Jim Chandler wrote:
Tim Wescott wrote:
As a "mill", the Smithy just can't compare to the real milling machines
I've used.
True. I use Bridgport mills at school, their very nice. Weight a few
tons, need 3 phase power, 3-axis DRO's, a tech. to maintain them,
tooling , you just walk 20ft and ask the storeman... - its one of my
favourite fantasies..
One full turn of the vertical feed gives you 4.2" of movement, which
severely compromises your ability to make controlled-depth cuts compared
to a knee mill's 0.1"/turn vertical movement (on the knee, at least).
Doesn't it have the fine feed handle? -
AFAIK, their the same as the
mini-mills arent they, at least from what I could see in the showroom.
And It is in desperate need of a DRO on the Y axis, you can (sorta)
get round it by using the adjustable depth stop on the column
It's flexible, so it's extremely difficult to make accurate, clean
milling cuts.
Yep. Goes real well for alumium, plastic.....it can be strengthened,
its on my "one day" list..
At the lowest setting of the milling head, I barely reach the milling
vise (and it's a thick one) with a normal-length mill, and that's with
the quill at it's longest and most flexible extension.
And thats a real easy one to fix - Little Machine Shop hvae a kit for
it, a longer rack which reaches down further towards the table. Good
value. Otherwise, use big spacers under your job...
The tail stock doesn't overhang, and the cross-feed slide is wide, so
you can't turn a shaft between centers all in one go -- at least not
unless I go buy an MT3 extension for the tail stock, which will make it
flexible.
The compound jib tapers a bit, so if I get it adjusted right for being
fully in it binds when it's fully out; if I loosen it to where it
doesn't bind when it's out then it's loose as all hell when it's fully in.
Having said all of that, for general lathe work it's not an unreasonable
machine. I've made any number of turned gizmos on it, and even without
a split nut it's not unreasonable to make threads with (5/8-40 threads
are fun, by the by). My only profound complaint about it as a lathe is
that dang tail stock -- I can live with the compound or replace it.
But I bought a Smithy instead of a plain ol' lathe because I needed to
do milling, and I have not been pleased with the machine in that regard
at all. Yes, I can make milling cuts with it, but it takes me hours to
do what it takes minutes to do on a knee mill, and the quality is very
poor compared to what I can easily achieve on that knee mill.
So I bitch about it, and one of these days I'll get a real milling
machine, hopefully followed by a better lathe.
Yep, me too. This is after I move to the country on a few acres, have
room for, and build, REALLY big sheds and workshop, get in 3 phase
power, - ..and I want a surface grinder as well.....and a Brobo cut
off saw.....and and and and........oh, and must remember to feed the
Flying Pigs every night
And as for materials - you use what you have/what you can get, and
feel pleased with yourself you worked around the problem....
Andrew VK3BFA.
--
Tim Wescott
Wescott Design Serviceshttp://www.wescottdesign.com
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