Delta DL40 Electronic Lathe

Delta DL40 Electronic Lathe

Post by Don Bar » Tue, 20 May 1997 04:00:00



I have a Delta DL40 Electronic Lathe.  It has a computer control, which
has caused me nothing but problems over the years.  Now that this is a
discontinued product, the cost of replacement is astronomical just for
ther controller part.  I decided that it is time to hard wire it to a
switch.  What I am looking for is some advice.  It has a G.E. DC motor
1.25 Horsepower, 12.2 AMPs and 90 Volts with a permananet wound magnet.  I
would like to go variable speed, with forward and reverse.

Any ideas would be greatly appreciated.

 
 
 

Delta DL40 Electronic Lathe

Post by Martin H. Eastbur » Tue, 20 May 1997 04:00:00


Don -
This sounds rather "standard" - you want Full-wave Rectification - a
Triac not an SCR -

This is within the relm of many hobby electronic types - with safety in
mind (not normally
the case with many).

Baring having a Ham friend or other, Try the local Motor repair shop or
Electrical supply.
I suspect Square D or such - has a standard unit that would simply bolt
on, wire in, and
away you go.  - I'd take you motor spec's with you.

Also - And I suspect this might be plauguing people - Some of these
units don't
have 'anti-spilke' or "snubing circuits" within the control.

DC motors are DC generators also. Move a winding across a magnetic field
- and the
winding has voltage on it. -

What zaps controllers is they get 'back-e.m.f.' - or voltage generated
that is
higher than what the controller can handle.

Many a ball pitch machine has/d this problem - I fixed a number years
ago.

A snubber is simply a 600V .1 uf cap in series with a 200 ohm resistor.
Sometimes 100.
Wattage = (E**2)/R (worst case)  or 120 * 120 / 200 = 72 watt.  i.e. 100
watt 200 ohm.
(a 25 watt will do nicely for either resistor since the power isn't
continious) (spikes).
The resistor doesn't draw current unless a spike (from a fast start/stop
) occurs.
The spike is composed of high frequency voltage/power/current - and it
will pass through
the capacitor like it wasn't there - and dump into the resistor.
The circuit should be across the motor leads.  +/- doesn't matter for
these parts.
The parts are available from Radio Shack - the resistors are square
ceramic blocks (power).
The caps are available there also.  Higher voltage is ok.  250V is
marginal, but ok .
Put them in a box ! - observe safety. - Use electric tape as needed.
Isolate from the
box - and not a cheap plastic one - you want safety in the shop -
breakage might be
ignored until to late.

Wow - didn't mean to go on like that - but there are some ideas.
Martin

Quote:

> I have a Delta DL40 Electronic Lathe.  It has a computer control, which
> has caused me nothing but problems over the years.  Now that this is a
> discontinued product, the cost of replacement is astronomical just for
> ther controller part.  I decided that it is time to hard wire it to a
> switch.  What I am looking for is some advice.  It has a G.E. DC motor
> 1.25 Horsepower, 12.2 AMPs and 90 Volts with a permananet wound magnet.  I
> would like to go variable speed, with forward and reverse.

> Any ideas would be greatly appreciated.


 
 
 

Delta DL40 Electronic Lathe

Post by Alan Reinha » Wed, 21 May 1997 04:00:00



:: I have a Delta DL40 Electronic Lathe.  It has a computer control, which
:: has caused me nothing but problems over the years.  Now that this is a
:: discontinued product, the cost of replacement is astronomical just for
:: ther controller part.  I decided that it is time to hard wire it to a
:: switch.  What I am looking for is some advice.  It has a G.E. DC motor
:: 1.25 Horsepower, 12.2 AMPs and 90 Volts with a permananet wound magnet.  I
:: would like to go variable speed, with forward and reverse.

Not sure, but I think you will need to retire the motor as well.
Till you try and recreate the dc power supply, you could have
just gone out and got a good used 1 or 2 hp motor.

This is why I like AC drives - they use 3 phase motors, and if the
drive did die, you COULD get a 3-phase converter and run it
from single phase power.

Regards -

Alan R.
http://www.netreach.net/~res
Home of the L1 - the Ultimate Artisan's lathe!

 
 
 

Delta DL40 Electronic Lathe

Post by JCALDWEL » Wed, 21 May 1997 04:00:00


Quote:

> I have a Delta DL40 Electronic Lathe.  It has a computer control, which
> has caused me nothing but problems over the years.  Now that this is a
> discontinued product, the cost of replacement is astronomical just for
> ther controller part.  I decided that it is time to hard wire it to a
> switch.  What I am looking for is some advice.  It has a G.E. DC motor
> 1.25 Horsepower, 12.2 AMPs and 90 Volts with a permananet wound magnet.  I
> would like to go variable speed, with forward and reverse.

> Any ideas would be greatly appreciated.

There are a number of commercial controllers available.  I have had good
luck with Baldor.  The BC-140  will handle up to 2 HP  90 volt or 180
volt PM DC motors.  the controller + heat sink for 1.5 HP at 115 V AC in
would prpbably run about $150+.  It is enclosed in a NEMA enclosure.  A
reversing switch is extra but you could put in one externaly for less
money.  Just don't try to reverse while the motor is turning.  I run my
Delta (an old one) with a 1 HP motor and the BC-140.

If you want to save a bit and build your own enclosure  The BC-141 will
work for 90 volt motors up to 1.5 HP.  They should be less than $100.
You would need a heat sink for it at 1.5 HP.

Surplus Center, Lincoln, NB 1-800-488-3401, has one from a tread mill
that will run 90 volt motors up to 15 amps - Item 15-1074 in the #270
catalog.  I bought one and it works fine on a tread mill.  Have not used
it on a lathe but the motors are esentially the same.  You have to build
your own box and provide a 10K pot for speed control. You supply the
switches.  The cost is $36.99 + shipping.

Jim Caldwell - Alabama

 
 
 

Delta DL40 Electronic Lathe

Post by Steve Worcest » Thu, 22 May 1997 04:00:00


I see Chuck Woodruff advertising in every AAW publication. Sells all
the motors you'll need! call him at (206)723-8487 or email at

he advertises 1/6hp up to 5hp, and I am sure he can set you up
good luck  - steve


Quote:
>I have a Delta DL40 Electronic Lathe.  It has a computer control, which
>has caused me nothing but problems over the years.  Now that this is a
>discontinued product, the cost of replacement is astronomical just for
>ther controller part.  I decided that it is time to hard wire it to a
>switch.  What I am looking for is some advice.  It has a G.E. DC motor
>1.25 Horsepower, 12.2 AMPs and 90 Volts with a permananet wound magnet.  I
>would like to go variable speed, with forward and reverse.

>Any ideas would be greatly appreciated.

--
Steve Worcester
Madera Creations, Plano, TX
"Really honey, I don't know where that $300 burl came from...
It wasn't there yesterday! " :)
 
 
 

Delta DL40 Electronic Lathe

Post by JLOR » Fri, 23 May 1997 04:00:00



Quote:

>I have a Delta DL40 Electronic Lathe.  ..snipe....  I
>would like to go variable speed, with forward and reverse.

W. W. Grainger; 1/8-2HP enclosed speed controller; 120/240VAC-90/180VDC
US$194.00; stock # 6Z386.

www.grainger.com/cgi-bin/G?5384180Y/catalog/index.htm
Youll need a business account, they dont sell retail.

A controller with built-in electronic brake and reverse is almost US$500.
I dont think you want an electronic brake on a lathe. Reversing a DC
motor is simply a matter of reversing the polarity by swapping the two
primary wires. Its cheaper to install a double-pole double-throw
(on-off-on) switch that reverses the polarity between the controller and
the motor.  I got one from the Surplus Center, Lincoln, NB 1-800-488-3407
for US$9.00 that will handle a 25 amp load.  As JCALDWELL indicated in a
previous post, you dont want to use this switch as an on-off switch.
Change the rotation with the motor power off.

============================
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        Timber Treasures