Re: greetings from new member (stiffness)
Posted by
DAFcnc
on 1999-05-13 03:50:49 UTC
On 13 May 99 , CAD_CAM_EDM_DRO@onelist.com entreated about
"[CAD_CAM_EDM_DRO] Digest Number 8":
} Message: 21
} Date: Thu, 13 May 1999 09:25:16 +0800
} From: Jim GREGG <gregg@...>
} Subject: Re: greetings from new member
}
} Hi All from a new list member.
}
} I concurr with Dan's comments re the slide bars. Many years ago I
owned an
} Emco Unimat SL (-Sherline sized Austrian lathe/mill - non CNC).
This used 2
} off 1/2"dia bars as the bedways, and about and 2 more 5/16" dia for
the
} cross slide ways. I eventually sold it because of spring in the
bars made
} it a very slow and difficult machine to get acceptable results on
anything
} other than aluminium. The printer bars are smaller diameter, and I
suspect
} will create frustration! Should be ok as aplotter though.
no, the bars I have are half inch on the main runner ,but slightly
less on the secondary ones. I will mostly be milling plastic anyway
So, I hear your advice, and acknowledge that you're all probably
right, but I'm building it anyway, I have no choice in materials at
this time.
} I currently run an EMCO CNC 5 lathe with milling head - converting
it to a 2
} 1/2 axis machine. Bit of a come down from the 11 ton Mori-Seki /
Fanuc
} machine i used in teaching!
yup
I spent this morning making some parts for my mill on a Maximat Super
11 lathe/mill. just center drilling and tapping some silver steel
rod (out of those printers :-) to make connectors, 5mm hole for the
motor shaft, M6 tap other end to take the end of the threaded rods
I'm using for lead screws.
and therein lies a tale..... I made a test connector yesterday with
just a plain 5mm hole and reduced the end of a threaded rod to fit.
what a *disarstar*, sloppy etc.
thought about it overnight (bear in mind this is the first time I've
used a lathe in something like 10 years, takes a moment for the
OS to reaccess the 'engineering' bit of the wetware)
hit on the 'tap one end' plan somewhere around 4am.....
purchased an M6 tapset on the way to work....
but while working I noticed that anything I put in the chuck was
noticeably off center, holes drilled proved this.....
then, while trimming a piece of rod with a small hole in it I heard a
strange nocking noise. stopped, checked the area, and found the bit
was bouncing at the hole edge leaving a pit, but only one end of the
hole. hmmm...... thought 'somethings loose'..... but carried on,
not wanting to fiddle with someone elses lathe...
a few minutes later the chuck came to a stop with one of the
attachment lugs facing me, and thats when I saw that the nut on that
lug was halfway down the lug! turned out all three nuts holding
the chuck to the backplate were loose, but I did at one point grab
the chuck and try to wobble it with no resulting feelings of
loosness. snugged them down and suddenly all was centered. much
nicer...
Note I'm not responsible for the upkeep on that lathe, it is in
another departments workshop, is seldom used and is generally in
excellent
condition. I and the workshop head can only surmise that some staff
member took it off and didn't put it back properly.
but now I know to check everything and assume nothing.....
steam and wind
--
David Forsyth DaForce A-T Iwr.Ru.Ac.Za
Keeper of the listserver for South African Railways fans _|_ His
Part time gricer, kiter, photographer, father etc etc | Way
http://www.ru.ac.za/departments/iwr/staff/daf/welcome.html | Up
"[CAD_CAM_EDM_DRO] Digest Number 8":
} Message: 21
} Date: Thu, 13 May 1999 09:25:16 +0800
} From: Jim GREGG <gregg@...>
} Subject: Re: greetings from new member
}
} Hi All from a new list member.
}
} I concurr with Dan's comments re the slide bars. Many years ago I
owned an
} Emco Unimat SL (-Sherline sized Austrian lathe/mill - non CNC).
This used 2
} off 1/2"dia bars as the bedways, and about and 2 more 5/16" dia for
the
} cross slide ways. I eventually sold it because of spring in the
bars made
} it a very slow and difficult machine to get acceptable results on
anything
} other than aluminium. The printer bars are smaller diameter, and I
suspect
} will create frustration! Should be ok as aplotter though.
no, the bars I have are half inch on the main runner ,but slightly
less on the secondary ones. I will mostly be milling plastic anyway
So, I hear your advice, and acknowledge that you're all probably
right, but I'm building it anyway, I have no choice in materials at
this time.
} I currently run an EMCO CNC 5 lathe with milling head - converting
it to a 2
} 1/2 axis machine. Bit of a come down from the 11 ton Mori-Seki /
Fanuc
} machine i used in teaching!
yup
I spent this morning making some parts for my mill on a Maximat Super
11 lathe/mill. just center drilling and tapping some silver steel
rod (out of those printers :-) to make connectors, 5mm hole for the
motor shaft, M6 tap other end to take the end of the threaded rods
I'm using for lead screws.
and therein lies a tale..... I made a test connector yesterday with
just a plain 5mm hole and reduced the end of a threaded rod to fit.
what a *disarstar*, sloppy etc.
thought about it overnight (bear in mind this is the first time I've
used a lathe in something like 10 years, takes a moment for the
OS to reaccess the 'engineering' bit of the wetware)
hit on the 'tap one end' plan somewhere around 4am.....
purchased an M6 tapset on the way to work....
but while working I noticed that anything I put in the chuck was
noticeably off center, holes drilled proved this.....
then, while trimming a piece of rod with a small hole in it I heard a
strange nocking noise. stopped, checked the area, and found the bit
was bouncing at the hole edge leaving a pit, but only one end of the
hole. hmmm...... thought 'somethings loose'..... but carried on,
not wanting to fiddle with someone elses lathe...
a few minutes later the chuck came to a stop with one of the
attachment lugs facing me, and thats when I saw that the nut on that
lug was halfway down the lug! turned out all three nuts holding
the chuck to the backplate were loose, but I did at one point grab
the chuck and try to wobble it with no resulting feelings of
loosness. snugged them down and suddenly all was centered. much
nicer...
Note I'm not responsible for the upkeep on that lathe, it is in
another departments workshop, is seldom used and is generally in
excellent
condition. I and the workshop head can only surmise that some staff
member took it off and didn't put it back properly.
but now I know to check everything and assume nothing.....
steam and wind
--
David Forsyth DaForce A-T Iwr.Ru.Ac.Za
Keeper of the listserver for South African Railways fans _|_ His
Part time gricer, kiter, photographer, father etc etc | Way
http://www.ru.ac.za/departments/iwr/staff/daf/welcome.html | Up