|
Posted by mark on February 15, 2008, 12:18 pm
Please log in for more thread options On 15 Feb, 14:20, Richard Edwards <richard-
edwardsbu...@burrsblueyonder.co.uk> wrote:
> wrote:
>
>
>
> >Still trying to refurbish the Boxford AUD.
>
> >The Cross slide has several thou of movement, mainly in the middle of
> >the travel.
>
> >The entire slide including the leadscrew can be pulled backwards and
> >forwards and it seems to be play between the leadscrew thrust bearing
> >and the saddle itself.
>
> >Is there any way to tighten this up?
>
> I do not know the AUD however I would strip and look closely at the
> "pinning" or "grubscrewing" of the screw assembly to the crosslide .
> sounds like slop there.
>
> >Someone suggested that I adjusted the cross slide dial, but it seems
> >immovable longitudinally on its shaft, though it can rotate to reset a
> >zero.
>
> >On a second issue, the Cross slide dial has 250 divisions,
> >corresponding I thought to 125 thou of movement per revolution, 250 thou
> >change in diameter.
>
> Alternatively 2.5mm =3D .10" You have a metric screw!
>
>
>
> >Putting a DTI seems to indicate only 100 thou, plus or minus the
> >movement mentioned above.
>
> >Is it likely that the leadscrew had been changed or am I
> >misunderstanding the nature of the beast?
>
> >Lastly, it has been fitted with a one HP single phase motor. The revs
> >drop perceptibly under any load. Indeed I can all but stall it by
> >applying =A0'squeeze' finger pressure to the main lead screw where it
> >leaves the gear box and did stall it parting off a 20 mm delrin bar
> >using a 1/16th parting tool. Using it on steel only removes dust rather
> >than swarf or chips with any tool.
>
> >Is this normal?
>
> Only on a Myford ;-)
>
> >Everything seems to turn freely and with the belts removed light
> >pressure turns the chuck. After 30 mins at the highest speed the
> >intermediate pulley shaft is warm, but the headstock is still cool to
> >the touch.
>
> Are you sure that you are stalling the motor and it is not just belt
> slip? Particularly the belt from intermediate pulley to the spindle.
> In a high gear with the belts fitted can you easily manually rotate
> the chuck and see the motor turn.>Any help gratefully accepted
> >Robin
>
> --
>
> Richard
>
> Email address is valid but remove burrs before sending!
from tonys site
Notes on Conversion to Single-phase Electrics
Whilst the rear-drive machines have a reasonable amount of space
behind the lathe to fit a replacement motor (although capacitor boxes
may have to be relocated) the under-drive lathes are a little tight on
room and, although the conversion is perfectly straightforward, there
are one or two simple points worth bearing in mind: the original
motor, if 3-phase, will almost certainly be 0.5 hp if originally
supplied to the education and training market, or 0.75 (and
occasionally 1 hp) from the industrial sector. Replacing it with a
modern 0.5 hp 1-phase motor will mean, inevitably, that the lathe will
no longer be able to start on top speed and, even if it does, will
have insufficient power to be useable. The experience of many users
suggests that a minimum of 1 hp is necessary for a successful
installation, whilst others consider that an even better solution is
to use a 1.5 h.p. motor. In the latter case, problems may be
encountered getting it into the limited space available, especially if
it's a modern type with a large plastic box shielding the capacitor
and terminals. First, install the motor as far back on its mounting
platform as possible (you will need to drill new holes in the plate)
having first checked that there is still enough room for the belt-
tensioning rod to function properly. Second, to enable the motor to
clear the floor, lift its mounting platform as high as possible on the
over-centre adjuster and use a shorter "link" belt for the drive - it
might even be necessary to adjust the length of the tensioning rod to
accomplish this. Another trick is to remove the plastic box from the
motor and remount the capacitor remotely, preferably in a place where
replacement is easy when it fails (as it will). Do not forget to
engineer a suitably safe cover for the terminals and clip any new
wires securely to the stand. As a last resort, because the base of the
motor compartment is open, the lathe stand can be mounted on raiser
blocks at each corner and the motor allowed to hang down into the
space created.
having read all that ...
I've converted a three phase one to single phase 3/4 hp ....and it ran
fine ...this was a big motor ,,,,dont know how you stuffed a 1hp
single phase in there .
you should be running in back gear to get the grunt and torque out of
it.
high speed light cuts.......... out of back gear .
all the best.markj
| 
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML Sitemap
>Still trying to refurbish the Boxford AUD.
>
>The Cross slide has several thou of movement, mainly in the middle of
>the travel.
>
>The entire slide including the leadscrew can be pulled backwards and
>forwards and it seems to be play between the leadscrew thrust bearing
>and the saddle itself.
>
>Is there any way to tighten this up?