Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

Joe Gwinn

There are a lot of models that will work well for a drill press. I
would suggest that you get a model with a display and programming
buttons on the unit. Some models do not have a display and are
programmed using a serial port. Okay for industry, but not so good for
the one person shop.

Dan

A good vendor is automationdirect.com. Fair pricing and good service. Their
least expensive unit in your horsepower should be just fine. Just a happy
customer.

Karl


"Joseph Gwinn" wrote in message
...
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

Joe Gwinn

Joseph Gwinn wrote:
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA
First, your drill press has to have a 3-phase motor. VFD's only work
with 3-phase motors.

AC tech, Yaskawa, Magnetek, Toshiba, Hitachi, Allen-Bradley, ......
all make small VFDs. Most over 1 HP are listed as requiring 3-phase
power, but they really don't. A 50% derating is a good idea, ie. use
a 1 HP unit to run a 1/2 Hp motor from single-phase power.

Jon

Indeed, automationdirect.com is a good choice. I have purchased 3 VFD's
from them and customer service, tech support and pricing are all very good.

Randy


"Karl Townsend" remove .NOT to reply wrote
in message ink.net...
A good vendor is automationdirect.com. Fair pricing and good service.
Their
least expensive unit in your horsepower should be just fine. Just a happy
customer.

Karl


"Joseph Gwinn" wrote in message
...
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

Joe Gwinn

all make small VFDs. Most over 1 HP are listed as requiring 3-phase
power, but they really don't. A 50% derating is a good idea, ie. use
a 1 HP unit to run a 1/2 Hp motor from single-phase power.

There are VFDs that are rated for single phase input. Teco brand is
one of them, and I have a couple Teco 2HP VFDs running 2HP motors
with single phase input. If the VFD is rated 2HP with single phase
input, and you want to drive a 2HP motor, I see no reason why you
need to spend a lot of extra money buying a bigger VFD.

There is one caveat; Application enginner told me to make sure
that the full load current of the motor is less than the max full
load current of the VFD. Usually is, but check to make sure.

I also have a 5HP Boston-Fincor VFD. This one is rated 5HP with 3phase
input and 2HP with single phase input. It runs a 2HP motor well with
single phase input. Never tried anything bigger.

Bottom line is to respect what the manufacture's ratings.

chuck

Jon Elson wrote:
First, your drill press has to have a 3-phase motor. VFD's only work
with 3-phase motors. ...

When you buy your motor (and matching VFD), get it bigger than you would
otherwise. 1 hp is good. It might seem large, but as you reduce the
speed, you also reduce power. So running at 5 Hz you only have 1/12 the
horsepower you have at 60 Hz. 'Cause power is the product of torque and
speed. The maximum torque for the motor is fixed (a matter of maximum
current), so the power decreases as speed does.

On a drill press that uses step pulleys to reduce speed, this does not
happen because torque is increased the same as speed is reduced.

Note that even at 5Hz I have plenty of power to tap. If I tried
drilling a large hole at 5 Hz, I would likely trip the VFD's current
limiter.

Also, 1 hp is a common, readily available, size for both motor and VFD.
Check eBay for motors and/or VFD's.

Bob

Thanks to all who have replied. I will look into all suggestions.

Joe Gwinn

In article ,
Joseph Gwinn wrote:
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

First off -- does your drill press have a three-phase motor? If
not, forget the VFD idea, unless you are willing to swap in a
three-phase motor.

An alternative, as long as talking about swapping motors, is a
DC motor and controller. Those are particularly good at low-speed
torque.

Perhaps some details about your drill press would help.

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

First off -- does your drill press have a three-phase motor? If
not, forget the VFD idea, unless you are willing to swap in a
three-phase motor.

No, it's single phase 110 volt 60 Hz.


An alternative, as long as talking about swapping motors, is a
DC motor and controller. Those are particularly good at low-speed
torque.

I did think of that, but needed the comparison.


Perhaps some details about your drill press would help.

It's a cute little Delta DP350 12" bench drill press that was on sale
for $200 at Rockler, which really serves woodworkers, not metalworkers.
I'm guessing that Rockler bought a bunch of DP350s, only to discover
that woodworkers don't want T-slot tables on their drill presses, and so
put them on sale. A 12" bench drillpress is a bit small for woodworking
too, but it's convenient for much of what I make. Although the table
could be larger.

The DP350 is variable speed (mechanical, with variable pulleys and a
belt), with a claimed minimum speed of 500 rpm, which turns out to be
too high for many things, especially countersinking for 1/4-inch flat
head cap screws in metal. Lots of squealing and chattering going on
unless lots of down pressure is used.

Severance countersinks seem to work better than MA Ford in this
application; don't know why. I'm using 6-flute countersinks. The MA
Ford countersink also tends to block up with impacted chips when working
in aluminum; steel not yet tried. The Severance is polished metal,
while the Ford is black oxide. Both are HSS.

All metal cutting operations are done with flood cooling, using Kool
Mist 77 in water, which seems to work quite well, although it probably
isn't as good a lubricant as oil.

The motor is 120 volts, 6.0 amps, 60 Hz, one phase, 1720 rpm, with one
capacitor bump on the housing. The nameplate volts and amps imply 720
watts, which is almost 1 HP, but this is most likely a peak value. Ad
materials claim 1/3 HP, which is plausible as a continuous rating. I
don't hear any clicking when it starts or stops, so I think it's
capacitor-run. I have not had the motor apart.

Given that the DP350 has mechanical variable speed, a slower
constant-speed motor could well suffice.

Of course, the solution should not cost more than simply buying another
drill press.

Joe Gwinn

It's a cute little Delta DP350 12" bench drill press that was on sale
for $200 at Rockler, which really serves woodworkers, not metalworkers.

.....cut....

Of course, the solution should not cost more than simply buying another
drill press.

You will spend more on the VFD and motor that you spent on the drill press.
Small surplus DC motors can be had much cheaper.

On Thu, 16 Jun 2005 09:32:03 -0400, Joseph Gwinn
wrote:

In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

First off -- does your drill press have a three-phase motor? If
not, forget the VFD idea, unless you are willing to swap in a
three-phase motor.

No, it's single phase 110 volt 60 Hz.


An alternative, as long as talking about swapping motors, is a
DC motor and controller. Those are particularly good at low-speed
torque.

I did think of that, but needed the comparison.


Perhaps some details about your drill press would help.

It's a cute little Delta DP350 12" bench drill press that was on sale
for $200 at Rockler, which really serves woodworkers, not metalworkers.
I'm guessing that Rockler bought a bunch of DP350s, only to discover
that woodworkers don't want T-slot tables on their drill presses, and so
put them on sale. A 12" bench drillpress is a bit small for woodworking
too, but it's convenient for much of what I make. Although the table
could be larger.

The DP350 is variable speed (mechanical, with variable pulleys and a
belt), with a claimed minimum speed of 500 rpm, which turns out to be
too high for many things, especially countersinking for 1/4-inch flat
head cap screws in metal. Lots of squealing and chattering going on
unless lots of down pressure is used.

Severance countersinks seem to work better than MA Ford in this
application; don't know why. I'm using 6-flute countersinks. The MA
Ford countersink also tends to block up with impacted chips when working
in aluminum; steel not yet tried. The Severance is polished metal,
while the Ford is black oxide. Both are HSS.

All metal cutting operations are done with flood cooling, using Kool
Mist 77 in water, which seems to work quite well, although it probably
isn't as good a lubricant as oil.

The motor is 120 volts, 6.0 amps, 60 Hz, one phase, 1720 rpm, with one
capacitor bump on the housing. The nameplate volts and amps imply 720
watts, which is almost 1 HP, but this is most likely a peak value. Ad
materials claim 1/3 HP, which is plausible as a continuous rating. I
don't hear any clicking when it starts or stops, so I think it's
capacitor-run. I have not had the motor apart.

Given that the DP350 has mechanical variable speed, a slower
constant-speed motor could well suffice.

Of course, the solution should not cost more than simply buying another
drill press.

Joe Gwinn

Put a 1/3-1/2 hp DC motor on it with one of the Minarick controllers
one fo the posters here has been selling and you will have something
you can control well enough.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

Given that the DP350 has mechanical variable speed, a slower
constant-speed motor could well suffice.

You may have to paste this onto one line:
http://www.green-trust.org/junkyardp...cerSMHWH61.pdf

A couple of us have done something similar,
and it's a lot cheaper than re-motoring...
--Glenn Lyford

In article ,
(Chuck Sherwood) wrote:

It's a cute little Delta DP350 12" bench drill press that was on sale
for $200 at Rockler, which really serves woodworkers, not metalworkers.

....cut....

Of course, the solution should not cost more than simply buying another
drill press.

You will spend more on the VFD and motor that you spent on the drill press.
Small surplus DC motors can be had much cheaper.

You're right about that. I already have a 1/3 HP 90 V PMDC motor I got
surplus for $20. The mounting is a bit awkward for the drill press
though. But possible, as the PMDC motor is far smaller than what's
there.

Hmm. This may well not work, because the original motor may have an
extra-long shaft that's shaft specially adapted to receive the
variable-speed pulley. I'll need to look at this more closely.

Joe Gwinn

In article ,
Gunner wrote:

On Thu, 16 Jun 2005 09:32:03 -0400, Joseph Gwinn
wrote:

In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

First off -- does your drill press have a three-phase motor? If
not, forget the VFD idea, unless you are willing to swap in a
three-phase motor.

No, it's single phase 110 volt 60 Hz.


An alternative, as long as talking about swapping motors, is a
DC motor and controller. Those are particularly good at low-speed
torque.

I did think of that, but needed the comparison.


Perhaps some details about your drill press would help.

It's a cute little Delta DP350 12" bench drill press that was on sale
for $200 at Rockler, which really serves woodworkers, not metalworkers.
I'm guessing that Rockler bought a bunch of DP350s, only to discover
that woodworkers don't want T-slot tables on their drill presses, and so
put them on sale. A 12" bench drillpress is a bit small for woodworking
too, but it's convenient for much of what I make. Although the table
could be larger.

[snip]

Given that the DP350 has mechanical variable speed, a slower
constant-speed motor could well suffice.

Of course, the solution should not cost more than simply buying another
drill press.

Joe Gwinn

Put a 1/3-1/2 hp DC motor on it with one of the Minarick controllers
one fo the posters here has been selling and you will have something
you can control well enough.

Now that I think about it, it may not be practical to replace the motor,
as its shaft may be long and specially adapted to receive the
variable-speed pulley. I'll need to look into this. It's time to oil
those pulleys anyway.

It occurs to me that it might be a good option to buy a belt and step
pulley drill press, but with a three-phase motor, plus a VFD, to achieve
convenient variable speed. This may be cheaper, and somewhat better
than the mechanical variable speed approach, especially in speed range.
One can always change the belts and pulleys to set the general speed
range without great loss of torque. The variable-speed drive drill
presses are quite a bit more expensive than non variable speed, and this
may pay for the VFD all by itself.

Reaction?

Joe Gwinn

On Thu, 16 Jun 2005 23:55:06 -0400, Joseph Gwinn
wrote:

In article ,
(Chuck Sherwood) wrote:

It's a cute little Delta DP350 12" bench drill press that was on sale
for $200 at Rockler, which really serves woodworkers, not metalworkers.

....cut....

Of course, the solution should not cost more than simply buying another
drill press.

You will spend more on the VFD and motor that you spent on the drill press.
Small surplus DC motors can be had much cheaper.

You're right about that. I already have a 1/3 HP 90 V PMDC motor I got
surplus for $20. The mounting is a bit awkward for the drill press
though. But possible, as the PMDC motor is far smaller than what's
there.

Hmm. This may well not work, because the original motor may have an
extra-long shaft that's shaft specially adapted to receive the
variable-speed pulley. I'll need to look at this more closely.

Joe Gwinn

Its not hard to machine a coupler and shaft extention. Might
take..what an hour if you were dawdling?
G

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Fri, 17 Jun 2005 00:06:01 -0400, Joseph Gwinn
wrote:

In article ,
Gunner wrote:

On Thu, 16 Jun 2005 09:32:03 -0400, Joseph Gwinn
wrote:

In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:
Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD are
suitable. When I search on "variable speed driver", I get a flood of
large industrial units that far exceed the needs of an ordinary drill
press. So, what makes and models should I look into? TIA

First off -- does your drill press have a three-phase motor? If
not, forget the VFD idea, unless you are willing to swap in a
three-phase motor.

No, it's single phase 110 volt 60 Hz.


An alternative, as long as talking about swapping motors, is a
DC motor and controller. Those are particularly good at low-speed
torque.

I did think of that, but needed the comparison.


Perhaps some details about your drill press would help.

It's a cute little Delta DP350 12" bench drill press that was on sale
for $200 at Rockler, which really serves woodworkers, not metalworkers.
I'm guessing that Rockler bought a bunch of DP350s, only to discover
that woodworkers don't want T-slot tables on their drill presses, and so
put them on sale. A 12" bench drillpress is a bit small for woodworking
too, but it's convenient for much of what I make. Although the table
could be larger.

[snip]

Given that the DP350 has mechanical variable speed, a slower
constant-speed motor could well suffice.

Of course, the solution should not cost more than simply buying another
drill press.

Joe Gwinn

Put a 1/3-1/2 hp DC motor on it with one of the Minarick controllers
one fo the posters here has been selling and you will have something
you can control well enough.

Now that I think about it, it may not be practical to replace the motor,
as its shaft may be long and specially adapted to receive the
variable-speed pulley. I'll need to look into this. It's time to oil
those pulleys anyway.

It occurs to me that it might be a good option to buy a belt and step
pulley drill press, but with a three-phase motor, plus a VFD, to achieve
convenient variable speed. This may be cheaper, and somewhat better
than the mechanical variable speed approach, especially in speed range.
One can always change the belts and pulleys to set the general speed
range without great loss of torque. The variable-speed drive drill
presses are quite a bit more expensive than non variable speed, and this
may pay for the VFD all by itself.

Reaction?

Joe Gwinn

I rather like step pully drill presses with a VFD, rather than a
variable speed drill press or a VS drill press with inverter for those
reasons. Same with a milling machine.
Far less complicated, less stuff to need to maintain due to wear and
the ability to simply change to a smaller or bigger pulley for
maintaining torque at variable tapping or drilling speeds is hard to
beat visa vis cost.

Stick a S&D drill bit, 1" or bigger, and the average VFD poops out
down there at low rpms, but simply change to the proper pully size,
and fine tune your vfd and voila..a hogger.
The rest of the time, using the medium pully and the VFD and you have
good speed and torque ranges for most drill sizes.

YMMV of course.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

Jon Elson wrote:
Joseph Gwinn wrote:

Another poster mentioned driving his drill press from a Variable Speed
Drive (VFD) to slow things down to a speed suitable for tapping. I'd
like to look into this, but don't know which makes and models of VFD
are suitable. When I search on "variable speed driver", I get a flood
of large industrial units that far exceed the needs of an ordinary
drill press. So, what makes and models should I look into? TIA

First, your drill press has to have a 3-phase motor. VFD's only work
with 3-phase motors.

AC tech, Yaskawa, Magnetek, Toshiba, Hitachi, Allen-Bradley, ......
all make small VFDs. Most over 1 HP are listed as requiring 3-phase
power, but they really don't. A 50% derating is a good idea, ie. use
a 1 HP unit to run a 1/2 Hp motor from single-phase power.

Jon


A local drive repair guy tells me that he can modify a 3 phase VFD to
run on single phase. He won't tell me how he does it. Do you have any
idea what he does?

stan

A local drive repair guy tells me that he can modify a 3 phase VFD to
run on single phase. He won't tell me how he does it. Do you have any
idea what he does?

1) He might be doing nothing because some VFDs will run an single phase.
2) He Might be replacing the input diodes with bigger diodes
3) He might be adding more filter caps and changing the diodes.

I wouldn't pay for a service unless I knew what he was doing and
why it makes the change possible.
chuck

In article ,
says...


A local drive repair guy tells me that he can modify a 3 phase VFD to
run on single phase. He won't tell me how he does it. Do you have any
idea what he does?


He takes the drive, puts it on the shelf, and gives it back
in few days along with a bill.g Virtually all small to
medium sized VFDs will run on single phase. The
manufacturers recommend that you derate drives that aren't
specifically designed to run on single phase, usually by
1/2 or 1/3, but I'm not convinced that's even necessary for
a drive that will see light and intermittent use.

It's possible the drives guy replaces, or adds to, the
filter caps in the power supply with larger units to reduce
the ripple that increases when running on single phase, but
most newer drives are so compact that I'm skeptical you
could do that without hanging the caps on the outside.

Ned Simmons

In article ,
Chuck Sherwood wrote:
A local drive repair guy tells me that he can modify a 3 phase VFD to
run on single phase. He won't tell me how he does it. Do you have any
idea what he does?

1) He might be doing nothing because some VFDs will run an single phase.
2) He Might be replacing the input diodes with bigger diodes

And perhaps a bigger filter capacitor, to reduce the ripple from
having only single phase to maintain the charge.

3) He might be adding more filter caps and changing the diodes.

And -- he *might* be strapping two of the three input lines
together to convince it that it has all three lines, if the VFD happens
to have sensors to shut it down if one line goes.

I wouldn't pay for a service unless I knew what he was doing and
why it makes the change possible.

Agreed.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

In article ,
Gunner wrote:

On Fri, 17 Jun 2005 00:06:01 -0400, Joseph Gwinn
wrote:

In article ,
Gunner wrote:

On Thu, 16 Jun 2005 09:32:03 -0400, Joseph Gwinn
wrote:

In article ,
(DoN. Nichols) wrote:

[snip]

Put a 1/3-1/2 hp DC motor on it with one of the Minarick controllers
one fo the posters here has been selling and you will have something
you can control well enough.

Now that I think about it, it may not be practical to replace the motor,
as its shaft may be long and specially adapted to receive the
variable-speed pulley. I'll need to look into this. It's time to oil
those pulleys anyway.

I looked at it this morning. It's a long shaft (~6 inches) with a long
keyway, plus two circlip grooves between which the variable pulley
mechanism sits, all metric. Definitely custom.

In another posting, Gunnar suggested machining an adapter shaft, which
could be done, but I don't know that I want to go to the trouble.

Instead, I'm thinking of getting a VFD that's big enough to run this
little 1/3 HP motor off one phase when I'm using the little drill press,
and this same VFD to run a larger 3-phase (probably a floor model) drill
press to be named.


The other issue that's developing in the DP350 is belt wear. The inside
of the housing has a layer of rubber dust already, and I've only had the
unit since 29 April 2005. I recall some complaints on Amazon about the
belts wearing out too fast, and some people saying that they had not had
that problem. I suspect that the cause is the sharp edges on the inside
of the pulley cones, where the facing cones mesh. The belt is
perpendicular to and runs over these sharp edges; this cannot be a good
idea. I plan to take the drive apart and round those edges with a hand
file. The cones are made of zinc-aluminum die metal.

The belts cost $38 from Delta; while $38 seems a bit much for a belt, I
did buy one, to have a backup. What Delta provides is a Tru-Power
V13x860.


It occurs to me that it might be a good option to buy a belt and step
pulley drill press, but with a three-phase motor, plus a VFD, to achieve
convenient variable speed. This may be cheaper, and somewhat better
than the mechanical variable speed approach, especially in speed range.
One can always change the belts and pulleys to set the general speed
range without great loss of torque. The variable-speed drive drill
presses are quite a bit more expensive than non variable speed, and this
may pay for the VFD all by itself.

Reaction?

Joe Gwinn

I rather like step pulley drill presses with a VFD, rather than a
variable speed drill press or a VS drill press with inverter for those
reasons. Same with a milling machine.
Far less complicated, less stuff to need to maintain due to wear and
the ability to simply change to a smaller or bigger pulley for
maintaining torque at variable tapping or drilling speeds is hard to
beat visa vis cost.

This was my instinct, but I'm glad to hear confirmation.


Stick a S&D drill bit, 1" or bigger, and the average VFD poops out
down there at low rpms, but simply change to the proper pully size,
and fine tune your vfd and voila..a hogger.

The other problem I'm having is large drill bits and countersinks
slipping in the chuck. With the original keyed jacobs-style chuck, it
was not possible to get it tight enough by hand, so I used a six-inch
length of 3/8 black iron pipe as a key extender. This does work,
although the key arms were right at the edge of bending, or a little bit
over the edge, and the whole operation was pretty time consuming.

So, I bought a Phase II keyless 1-13mm chuck (Travers # 63-099-024, $32)
and it's a lot faster, but it too will slip on the larger stuff. I got
a surplus spanner wrench that allows me to hold the top (narrow) knurled
ring while hand tightening the body of the chuck, and this works for all
but the MA Ford 5/8 inch countersink (which has a very smooth shank).
There is noticeable added tightening when using the spanner.

I think I'll roughen the shank of the MA Ford countersink with flooded
wet-dry sandpaper. It really doesn't need to be polished.

I'm wondering if a better chuck would help. I looked at the
ball-bearing jacobs-style chucks, and at the more expensive keyless
chucks, such as those made by Rohm. Any opinions?


The rest of the time, using the medium pulley and the VFD and you have
good speed and torque ranges for most drill sizes.

YMMV of course.

Yes, but I gather that you have direct experience with this setup, and
it works as one might expect and hope that it would. Said another way,
there were no surprises. This is often the key.


Joe Gwinn

In article ,
Joseph Gwinn wrote:
In article ,

[ ... ]

I looked at it this morning. It's a long shaft (~6 inches) with a long
keyway, plus two circlip grooves between which the variable pulley
mechanism sits, all metric. Definitely custom.

In another posting, Gunnar suggested machining an adapter shaft, which
could be done, but I don't know that I want to go to the trouble.

Instead, I'm thinking of getting a VFD that's big enough to run this
little 1/3 HP motor off one phase when I'm using the little drill press,
and this same VFD to run a larger 3-phase (probably a floor model) drill
press to be named.

Hmm ... you *do* know that *single* phase induction motors do
not start well (if at all) at anything other than their nominal
frequency? Typically, a 60 Hz motor can be started on 50 Hz and vice
versa, but run the frequency much up or down from there and you will
have problems. (A cap start motor could benefit from changing the cap
value depending on the frequency, but I'm not at all sure that it will
have much torque in any case.) I don't think that you can make this
usable at all. You won't have enough speed range to do you much good,
and you will always have to start it at the nominal frequency and then
adjust to what you want and see whether the motor stalls before you even
put any load on it.

[ ... ]

Stick a S&D drill bit, 1" or bigger, and the average VFD poops out
down there at low rpms, but simply change to the proper pully size,
and fine tune your vfd and voila..a hogger.

The other problem I'm having is large drill bits and countersinks
slipping in the chuck. With the original keyed jacobs-style chuck, it
was not possible to get it tight enough by hand, so I used a six-inch
length of 3/8 black iron pipe as a key extender. This does work,
although the key arms were right at the edge of bending, or a little bit
over the edge, and the whole operation was pretty time consuming.

So, I bought a Phase II keyless 1-13mm chuck (Travers # 63-099-024, $32)
and it's a lot faster, but it too will slip on the larger stuff. I got
a surplus spanner wrench that allows me to hold the top (narrow) knurled
ring while hand tightening the body of the chuck, and this works for all
but the MA Ford 5/8 inch countersink (which has a very smooth shank).
There is noticeable added tightening when using the spanner.

I think I'll roughen the shank of the MA Ford countersink with flooded
wet-dry sandpaper. It really doesn't need to be polished.

I'm wondering if a better chuck would help. I looked at the
ball-bearing jacobs-style chucks, and at the more expensive keyless
chucks, such as those made by Rohm. Any opinions?

Note that Albrecht makes a keyless chuck with diamond
impregnated jaws, so they will grip on a hardened shank. I'm not sure
that you can find those with Jacobs taper sockets for an arbor for your
drill press. I think that they may be only in the "integral shank"
line, where you can get them with R8 shanks, or NMTB 30 or 40 or 50
shanks to go right into your milling machine.

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:
In article ,

[ ... ]

I looked at it this morning. It's a long shaft (~6 inches) with a long
keyway, plus two circlip grooves between which the variable pulley
mechanism sits, all metric. Definitely custom.

In another posting, Gunnar suggested machining an adapter shaft, which
could be done, but I don't know that I want to go to the trouble.

Instead, I'm thinking of getting a VFD that's big enough to run this
little 1/3 HP motor off one phase when I'm using the little drill press,
and this same VFD to run a larger 3-phase (probably a floor model) drill
press to be named.

Hmm ... you *do* know that *single* phase induction motors do
not start well (if at all) at anything other than their nominal
frequency? Typically, a 60 Hz motor can be started on 50 Hz and vice
versa, but run the frequency much up or down from there and you will
have problems. (A cap start motor could benefit from changing the cap
value depending on the frequency, but I'm not at all sure that it will
have much torque in any case.) I don't think that you can make this
usable at all. You won't have enough speed range to do you much good,
and you will always have to start it at the nominal frequency and then
adjust to what you want and see whether the motor stalls before you even
put any load on it.

I suspected there would be a problem, but can't say that I knew it.
This is why I tried the idea out on the group. At this point I'm
collecting ideas. And if I go the VFD with 3-phase motor approach to
variable speed, it won't cost me much to try it out on the little
1-phase drill press. I probably only need to be able to run at say 1/2
speed, and could have a run capacitor sized for 30 Hz.

So far, torque has not been the problem. If anything, the problem has
been that the chuck doesn't pinch the tool shanks nearly tightly enough,
so the chuck slips rather than the motor stalling or even laboring.


Stick a S&D drill bit, 1" or bigger, and the average VFD poops out
down there at low rpms, but simply change to the proper pulley size,
and fine tune your vfd and voila..a hogger.

The other problem I'm having is large drill bits and countersinks
slipping in the chuck. With the original keyed jacobs-style chuck, it
was not possible to get it tight enough by hand, so I used a six-inch
length of 3/8 black iron pipe as a key extender. This does work,
although the key arms were right at the edge of bending, or a little bit
over the edge, and the whole operation was pretty time consuming.

So, I bought a Phase II keyless 1-13mm chuck (Travers # 63-099-024, $32)
and it's a lot faster, but it too will slip on the larger stuff. I got
a surplus spanner wrench that allows me to hold the top (narrow) knurled
ring while hand tightening the body of the chuck, and this works for all
but the MA Ford 5/8 inch countersink (which has a very smooth shank).
There is noticeable added tightening when using the spanner.

I think I'll roughen the shank of the MA Ford countersink with flooded
wet-dry sandpaper. It really doesn't need to be polished.

I'm wondering if a better chuck would help. I looked at the
ball-bearing jacobs-style chucks, and at the more expensive keyless
chucks, such as those made by Rohm. Any opinions?

Note that Albrecht makes a keyless chuck with diamond
impregnated jaws, so they will grip on a hardened shank. I'm not sure
that you can find those with Jacobs taper sockets for an arbor for your
drill press. I think that they may be only in the "integral shank"
line, where you can get them with R8 shanks, or NMTB 30 or 40 or 50
shanks to go right into your milling machine.

It's a J33 taper, and Albrecht does make a diamond-impregnated keyless
chuck to fit (Travers # 63-005-558 for instance), and I've got to
believe that it would work well. But I'd feel a bit silly putting a
$326 chuck on a $200 drill press.

There is a pecking order of cost and value, and I'm trying to find
something a bit better than what I have. Any ideas?

No milling machine yet, for lack of a place to put it. Likewise lathe.
But soon. I'm slowly building my shop up, often on the debris of what
was once a vibrant machine-tool and manufacturing industrial base in New
England. Also, judging by what turns up on the used tool market, there
must be a lot of mechanics retiring and selling their tools by the pound.

Joe Gwinn

In article ,
Joseph Gwinn wrote:
In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:

[ ... ]

Instead, I'm thinking of getting a VFD that's big enough to run this
little 1/3 HP motor off one phase when I'm using the little drill press,
and this same VFD to run a larger 3-phase (probably a floor model) drill
press to be named.

Hmm ... you *do* know that *single* phase induction motors do
not start well (if at all) at anything other than their nominal
frequency? Typically, a 60 Hz motor can be started on 50 Hz and vice
versa, but run the frequency much up or down from there and you will
have problems. (A cap start motor could benefit from changing the cap
value depending on the frequency, but I'm not at all sure that it will
have much torque in any case.) I don't think that you can make this
usable at all. You won't have enough speed range to do you much good,
and you will always have to start it at the nominal frequency and then
adjust to what you want and see whether the motor stalls before you even
put any load on it.

I suspected there would be a problem, but can't say that I knew it.
This is why I tried the idea out on the group. At this point I'm
collecting ideas. And if I go the VFD with 3-phase motor approach to
variable speed, it won't cost me much to try it out on the little
1-phase drill press. I probably only need to be able to run at say 1/2
speed, and could have a run capacitor sized for 30 Hz.

Well ... try paralleling a second start capacitor of the same
value with the original one. This will only help with starting,
however, and I suspect that the torque needed to stop the spindle will
still be lower than you would like.

So far, torque has not been the problem. If anything, the problem has
been that the chuck doesn't pinch the tool shanks nearly tightly enough,
so the chuck slips rather than the motor stalling or even laboring.

[ ... ]

I think I'll roughen the shank of the MA Ford countersink with flooded
wet-dry sandpaper. It really doesn't need to be polished.

I'm wondering if a better chuck would help. I looked at the
ball-bearing jacobs-style chucks, and at the more expensive keyless
chucks, such as those made by Rohm. Any opinions?

Note that Albrecht makes a keyless chuck with diamond
impregnated jaws, so they will grip on a hardened shank. I'm not sure
that you can find those with Jacobs taper sockets for an arbor for your
drill press. I think that they may be only in the "integral shank"
line, where you can get them with R8 shanks, or NMTB 30 or 40 or 50
shanks to go right into your milling machine.

It's a J33 taper, and Albrecht does make a diamond-impregnated keyless
chuck to fit (Travers # 63-005-558 for instance), and I've got to
believe that it would work well. But I'd feel a bit silly putting a
$326 chuck on a $200 drill press.

I can understand that.

There is a pecking order of cost and value, and I'm trying to find
something a bit better than what I have. Any ideas?

Hmm ... Can you find an ER collet adaptor with a MT shank to fit
your drill press? That, and a few selected collets might do the job for
you.

An alternative might be to simply get the tools you need with a
Morse taper shank to fit the drill press. I'm not sure whether a Ford
countersink is available with a MT shank, but you could check for it.
You might even call a good vendor like MSC (if you don't find it in
their catalog) and ask them. I've had them call the manufacturers for a
special at times -- and it wasn't *too* expensive. (I needed a
non-standard set of chasers for a Geometric die head for my turret
lathe.)

I know that for larger drill bits, I use MT shanks directly in
my drill press. (Though I've not had any problems with slipping chucks
in that one. It is a MT-2 spindle, with a Jacobs keyless chuck (akin to
the Albrecht in design and behavior). Granted, I did not pay new price
for that chuck, but lucked into a barely used one. I only had to get a
good arbor to fit my drill press spindle. Most of my other drill chucks
are Albrecht, with one Rohm (3/8" and quite good) and one Polish made
clone of an Albrecht (not as nice) in my bigger (12" swing) lathe
Tailstock. The key type Jacobs chucks are a real pain in a lot of
situations.

No milling machine yet, for lack of a place to put it. Likewise lathe.
But soon. I'm slowly building my shop up, often on the debris of what
was once a vibrant machine-tool and manufacturing industrial base in New
England. Also, judging by what turns up on the used tool market, there
must be a lot of mechanics retiring and selling their tools by the pound.

Good Luck with that,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:
In article ,
(DoN. Nichols) wrote:

In article ,
Joseph Gwinn wrote:

[ ... ]

Instead, I'm thinking of getting a VFD that's big enough to run this
little 1/3 HP motor off one phase when I'm using the little drill press,
and this same VFD to run a larger 3-phase (probably a floor model) drill
press to be named.

Hmm ... you *do* know that *single* phase induction motors do
not start well (if at all) at anything other than their nominal
frequency? Typically, a 60 Hz motor can be started on 50 Hz and vice
versa, but run the frequency much up or down from there and you will
have problems. (A cap start motor could benefit from changing the cap
value depending on the frequency, but I'm not at all sure that it will
have much torque in any case.) I don't think that you can make this
usable at all. You won't have enough speed range to do you much good,
and you will always have to start it at the nominal frequency and then
adjust to what you want and see whether the motor stalls before you even
put any load on it.

I suspected there would be a problem, but can't say that I knew it.
This is why I tried the idea out on the group. At this point I'm
collecting ideas. And if I go the VFD with 3-phase motor approach to
variable speed, it won't cost me much to try it out on the little
1-phase drill press. I probably only need to be able to run at say 1/2
speed, and could have a run capacitor sized for 30 Hz.

Well ... try paralleling a second start capacitor of the same
value with the original one. This will only help with starting,
however, and I suspect that the torque needed to stop the spindle will
still be lower than you would like.

That's a good idea.

Running at half frequency (30 Hz versus 60 Hz) requires that the drive
voltage also be cut in half, to maintain constant flux density within
the motor. I don't think the running speed regulation is greatly
affected, but I suspect that the breakdown torque (where the motor
stalls) is cut in half compared to what it would have been had the motor
been wound for 30 Hz. The answer is probably documented in application
notes somewhere.

So the question will probably be how close to breakdown torque we are at
present. The mechanical variable-speed system drops the speed to 536
rpm for a motor speed of 1750 rpm, a 3.26:1 ratio. (These are measured
values, at zero load.) The torque at the chuck will increase by a like
ratio, and I have not seen the motor even laboring.

For the record, the ad copy claims 500 rpm to 3100 rpm, and I measure
536 to 2948 rpm (no load), so the ad copy is a bit optimistic. The
motor turns at about 1750 rpm, at the motor shaft.


So far, torque has not been the problem. If anything, the problem has
been that the chuck doesn't pinch the tool shanks nearly tightly enough,
so the chuck slips rather than the motor stalling or even laboring.

[ ... ]

I think I'll roughen the shank of the MA Ford countersink with flooded
wet-dry sandpaper. It really doesn't need to be polished.

I'm wondering if a better chuck would help. I looked at the
ball-bearing jacobs-style chucks, and at the more expensive keyless
chucks, such as those made by Rohm. Any opinions?
[snip]

There is a pecking order of cost and value, and I'm trying to find
something a bit better than what I have. Any ideas?

Hmm ... Can you find an ER collet adaptor with a MT shank to fit
your drill press? That, and a few selected collets might do the job for
you.

This is something to consider when I get the floor mount drill press,
but the cute little Delta DP350 has only the JT33 taper. I like the
size of the DP350 for many things, but in retrospect I'm not sure the
mechanical variable speed was that good an idea, although it sure is
convenient.


An alternative might be to simply get the tools you need with a
Morse taper shank to fit the drill press. I'm not sure whether a Ford
countersink is available with a MT shank, but you could check for it.
You might even call a good vendor like MSC (if you don't find it in
their catalog) and ask them. I've had them call the manufacturers for a
special at times -- and it wasn't *too* expensive. (I needed a
non-standard set of chasers for a Geometric die head for my turret
lathe.)

I know that for larger drill bits, I use MT shanks directly in
my drill press. (Though I've not had any problems with slipping chucks
in that one. It is a MT-2 spindle, with a Jacobs keyless chuck (akin to
the Albrecht in design and behavior). Granted, I did not pay new price
for that chuck, but lucked into a barely used one. I only had to get a
good arbor to fit my drill press spindle. Most of my other drill chucks
are Albrecht, with one Rohm (3/8" and quite good) and one Polish made
clone of an Albrecht (not as nice) in my bigger (12" swing) lathe
Tailstock. The key type Jacobs chucks are a real pain in a lot of
situations.

It pays to be lucky. So, the Rohm chucks are good. That's useful to
know. I assume you mean the Rohm keyless chuck. While the ball
bearing keyed chucks are better, they are still keyed.


No milling machine yet, for lack of a place to put it. Likewise lathe.
But soon. I'm slowly building my shop up, often on the debris of what
was once a vibrant machine-tool and manufacturing industrial base in New
England. Also, judging by what turns up on the used tool market, there
must be a lot of mechanics retiring and selling their tools by the pound.

Good Luck with that,

Thanks. I used to have access to a small machine shop and lived in
apartments. Now I have a wife and a house (now with a small workshop
area), but too far away from that machine shop. So, I'm seriously short
of iron toys, and a lot has changed over the years. At least the wife
doesn't mind the iron toys, even the noisy ones. But I don't think I'll
start a foundry operation.

Joe Gwinn