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issatree
28th June 2014, 08:51 PM
Hi All,
Is it possible or worth it to get a more powerful Motor for my Mini Ledacraft Wood Lathe.
At the moment it is a ½HP. woodn't mind a ¾HP.
Wood the motor from the likes of the yellow Woodfast fit, as I believe it is ¾HP.
I wood rather not change my Lathe as I find it an excellent Wood Lathe, just right for doing Demo's.

Treecycle
28th June 2014, 10:01 PM
I think you will find the Woodfast (http://www.cwsonline.com.au/shop/item/woodfast-m305-midi-lathe) only has a 1/2hp motor, both yellow and green models.

BobL
28th June 2014, 10:27 PM
You might be battling to notice the difference between a 1/2 and 3/4HP motor.

I fitted a 1HP 3 phase motor and a VFD to my woodfast midi but as the motor would not fit in the same location as the original motor there was a lot of mucking about to install it.
The only obvious difference I can observe is that I have to change gears less often but thats due to the VFD not the motor.

Paul39
29th June 2014, 02:09 AM
Hi All,
Is it possible or worth it to get a more powerful Motor for my Mini Ledacraft Wood Lathe.
At the moment it is a ½HP. woodn't mind a ¾HP.
Wood the motor from the likes of the yellow Woodfast fit, as I believe it is ¾HP.
I wood rather not change my Lathe as I find it an excellent Wood Lathe, just right for doing Demo's.

As you take it to demos, stick it in your vehicle and go to your nearest electric motor shop that repairs and rebuilds motors.

With luck they will have a rebuilt or used 3/4 hp motor the same size, mount, and shaft size. Or give you a price on a new one.

A 3/4 hp should give you 1/3 more power. If the price is prohibitive, going to one pulley slower or using a smaller tool will help lack of power.

The higher the speed, the less torque or twisting power is available at the spindle.

Some Asian motors are optimistic in their ratings of horse power. One HP draws 745.7 watts, divide your local voltage into watts to get amps.

Assuming 240 volts, divide that into 745.7 watts, one HP will draw 3.107 amps. A 3/4 HP, 2.33 amps, a 1/2 HP 1.554 amps. 3/4 HP will draw 559.28 watts, 1/2 HP 372.85.

The motor nameplate should have watts or amps drawn at a listed voltage. Multiply your local volts times listed amps on your motor to get watts. Also some motors are more efficient than others. Higher efficiency costs more to buy but gives more power for the same size.

Making sure your existing motor is spinning freely, oil if needed, check that the spindle is not dragging, and be sure the pulleys are clean and belt is in good condition. All of this tuning will help a little bit.

Mobyturns
29th June 2014, 07:49 AM
Contact David at SE QLD Woodworking Supplies as he has aftermarket motor + VS units for mini lathes around $300 from memory. The VS unit on our Nova Mercury died a few years back & we replaced it with one of David's units. Works well.

One caution is that the lower pulley on many of the mini - midi lathes have a small shaft bore which limits machining them out so you will probably have to reduce the motor shaft dia. Allow for another $100+ for machining the motor shaft in your budget.

Before upgrading consider the unit as a whole - is the lathe up to the task that an increase in power will allow you to take on?

BobL
29th June 2014, 11:03 AM
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A 3/4 hp should give you 1/3 more power. If the price is prohibitive, going to one pulley slower or using a smaller tool will help lack of power.
It's 50% more power, which means the operator can theoretically apply 50% more pressure on a tool, but that will not appear to make much of a difference in practice.


Some Asian motors are optimistic in their ratings of horse power. One HP draws 745.7 watts, divide your local voltage into watts to get amps.
Assuming 240 volts, divide that into 745.7 watts, one HP will draw 3.107 amps. A 3/4 HP, 2.33 amps, a 1/2 HP 1.554 amps. 3/4 HP will draw 559.28 watts, 1/2 HP 372.85.
These VxI base calculations assume 100% energy conversion efficiency which small motors are generally poor at doing so the actual power generated for those currents will be ~15% less.

HP and current draw ratings on motors are semi-nominal values anyway as motors don't draw a single current or output a single value of HP. The current draw and HP output varies from close to zero at no load to as much as twice the rating when it stalls or thermally cuts out. It's up to the manufacturer to determine what sort of a load it can tolerate for what periods of time etc and come up with an HP/current rating. Not all of the increased current drawn is converted into mechanical power (HP) as the motor become increasingly inefficient and ends up generating a lot more heat which is why most motors have thermal cut outs on them.

A conservative manufacturer will usually choose an HP rating that is lower in the working HP range of the motor while another manufacturer another rate it higher. There is nothing fraudulent about this even though it may result in a reduced efficiency and motor life. There are international Standards for motors that require motors to meet a certainly level of efficiency at their rated HP which Asian manufacturers wishing to sell into Europe and the US need to meet. As these standards become more effective this should reduce the spurious claims being made about motor HPs.

All of the Asian motors I have tested were able to perform at their nominal HP rating. The only motor I have found that could not achieve its HP rating was an older Australian made motor which overheated and tripped out as it approached its rated HP so could have been something wrong with it. Testing for longevity of the motor at it's HP rating is another matter.

hughie
4th July 2014, 10:20 AM
Hi All,
Is it possible or worth it to get a more powerful Motor for my Mini Ledacraft Wood Lathe.
At the moment it is a ½HP. woodn't mind a ¾HP.
Wood the motor from the likes of the yellow Woodfast fit, as I believe it is ¾HP.
I wood rather not change my Lathe as I find it an excellent Wood Lathe, just right for doing Demo's.

If your current motor is single phase 1/2hp ie 240v then going to a three phase 3/4hp motor it should be darn near the same size. Added to that your power usage should be better plus better torque, not too mention the handiness of a variable speed. The down side would be the loss of torque at low speeds.

Have a look at Baldor electric motors they specialize in smaller dia motor bodies and should have one to fit as mountings follow a international standard

Baldor (http://www.edingtonagencies.com.au/baldor?gclid=COG29uajqr8CFRaVvAod4rEABg)

Baldor Electric Company, a leader in energy efficient electric motors, linear motors and adjustable speed drives industry (http://www.baldor.com/)

There are set ups around that will supply full torque but will more expensive.