Re: What do you think of this mill?

--- In CAD_CAM_EDM_DRO@y..., "deanc500" <deanc@v...> wrote:

> Hi, I am looking for a mill drill to convert to cnc and I noticed

this

> one at House of Tools up here in Canada. It's got a 2HP 220V spindle
> motor and dovetail ways. The price seem pretty good at $1670US. They
> just started selling this model under their house brand name Force.
> What do you think?
>
> http://www.houseoftools.com/product.htm?pid=169868
>
> Dean

Looks very similiar to Rong Fu RF-45 that I just converted but see a
few differences, system for raising head on column looks different
and listed spindle speeds are different. RF-45 is around $2300 US
from MSC. Converted mine to servo with Camtronics set up. It is a
big step up from Taig I had and with a couple exceptions I am pleased
with it so far and I would do it again. A used Bridgeport etc is not
very good option for me due to location so this machine was about as
big as I wanted to ship.

Two issues I have are max. spindle rpm is 1500 mine and gear head is
really noisy at this speed, RF manual indicates they make a model
that goes up to 3000 rpm but guess I would wonder about gear train at
that speed. Second issue is dealing with backlash in the Z axis.
Problem is backlash in rack and pinion drive and worm gear assembly.
Dan at Camtronics had good idea to take this out but additional
problem I had was runout between pitch line of worm shaft and bearing
diameters on the shaft so backlash between worm shaft and worm wheel
varies as shaft rotates, shaft I mean is the one connecting to fine
feed wheel which is now driven by Z axis servo. I called MSC and they
sent out another shaft asap agreeing that this shouldn't be like this
but replacement was just as bad. I came up with a bandaid fix that
reduced TIR on shaft from .012 to about .002 so I can now live with
it until I come up with a better idea.

Enough rambling - if you purchase one, e-mail off line and I can e-
mail pictures of conversion parts I made including ball screw
installation.

Rick Crisenbery