lathe power feed

[crimson]

Sick of not having access to a power feed on my old lathe i decided to make an electric power feed, But i havent a clue what type of motor or what power i will need so it doesnt bog down when i take a cut. i have a 1/2 hp motor off a wood lathe in my possetion, but was thinking a windsheild wiper motor since they are allready geared down. what do you guys think.

she's old but runs smooth

[Darren]

Hi Crimson and welcome to the forum,

Nice first post, and that's a nice looking lathe too you have there. I do like the older machines and why I'm playing with one myself. Well I will be when I get it going...

I've been thinking a lot about power drives myself, mainly for my miller. I think windscreen motors would be a good candidate but you might want to think about some sort of speed control. Variable voltage supply should do it. I'm fortunate in having quite a few from my valve amplifier projects that I could use.

As I see it there are several options available. You could feed the motor 12V from a 240/12V transformer or whatever your mains in over there? But you would have to rectify the 12AC to DC for the motor. Beware of the amperage for the diodes and stuff. Nothing complicated. Also when you rectify the 12AC to DC the voltage will rise a touch to about 14V. This should be ok for the motor and give a little more scope.

Then you want a way to vary the voltage, I would use a mains variac on the mains side, but only because I have a couple handy. Or you can make a DC variable voltage controller. That's a little more complicated and now you really do have to watch the amperage the motor will draw. Components will need to be rated at twice this if you want reliability.

If you don't know how to do this then perhaps you would be better off buying a bench power supply, but they will not be cheap.



Another option would be an old treadmill motor. Treadmills have a variable supply built in. This would be the easy way out as secondhand treadmills can be found quite easily.
People have great ideas about slimming, but the exercise soon puts them off. I think they believe the treadmill does the work for them 

There that should give you something to think about....

[Bernd]

Welcome Crimson.

I see some gearing on the lathe, but it doesn't look like it's connected to anything.

A windscreen wiper motor my be a bit to slow do to the worm wheel drive. As far as a treadmill motor is concerned they would need to be geared down quite a bit. One motor I have has a peak RPM of over 6000RPM. A bit fast for using as a feed motor, but would probably work.

Other motors to use would be from a wheel chair, or perhaps the motors that are in kids ride around toys.

Regards,
Bernd

[John Hill]

Hi Crimson and it is good to see another antipodean join the site .

The mechanics of adding power feed would be quite a challenge for someone like me but the job would be much easier with a direct drive.  Something like a big stepper motor.

Usually such things would be expensive but living in Australia you will have Fisher and Paykel washing machines at your local dump, their Smart Drive series are driven by a single big 3 phase stepper motor and these have enough grunt to be directly mounted on the existing feed wheel without further gearing.  Once mounted you can still turn the handle by hand when the power to the motor is off which you would not be able to do if any mechanism involving a worm reduction was attached.

Stepper motor drives can be complex electronic devices though there are plenty of designs about,  you could use the driver from the washing machine if you knew enough to run it slow enough for your application.

But this is a lathe so you likely want the feed to be in some proportion of the spindle RPM.  By mounting a switch on the spindle you could step the motor per so many revolutions of the spindle.

There are a bunch of Aussies, and the odd Kiwi (very odd ), who know a bit about these motors over at http://www.thebackshed.com/Windmill/FORUM1/forum_topics.asp?FID=11  the site is oriented towards wind turbine generators (for which some members use the F&P motor) but they are a great source for information on the motors and how to modify them etc.

Somewhere on the web there is a milling machine fitted with these motors, I forget where I saw it, ('Instructables" maybe ? ) including a circuit diagram for a controller.

NB:  Most steppers have just two phases but the F&P has three so a regular stepper motor driver might not be useable.

Cheers mate!

[sbwhart]

Hi Crimson welcome aboard.

Electrical bits are not my strong point, but from the picture it looks like that lathe had power feed at one point so her's a few questions:- What's the make of the lathe:- are there bits missing from it:- have you tried getting hold of or making the missing bits.

Cheers

Stew

[John Hill]

Ah here it is,  three washing machine motors on someone's mill!



from this site...
http://www.instructables.com/id/Make-your-own-cnc-controller/

[crimson]

it looks like that lathe had power feed at one point so her's a few questions:- What's the make of the lathe:- are there bits missing from it:- have you tried getting hold of or making the missing bits.

i bought this from a bloke in marybourgh who bought it off a local engineering bussiness but when he got it he didnt ask for any of the gears and didnt recieve them. i have been searching for them, similar types of lathes appear on ebay sometimes but people are hesitant to part them out . the make of the lathe im not really sure ive done internet searches but all the information i can get, is off this plate.as for making the gears i dont have the facilities avalible.

thinking about this further today i decided to see if i could scavenge something for the back of the shed and to great sucess i managed to find a electric weed trimmer with a 1000w motor this is almost perfect it can be plugged straight into mains power and the trigger acts as a speed controller. i also managed to find an old electric razor scooter but the plastic puley and belt drive looked to flimsy for this sort of application.
  possible drive for power feed, paid 1$ for them from the scrap merchants
my lathe almost naked, better pic than before

[sbwhart]

Hi Ron it looks a real nice lathe probibly based on the South Bend this site http://www.lathes.co.uk/page21.html  has lots of info on old lathes perhaps you can find yours here or email the chap who may be able to help. You don't have to make your own gears thers plenty of gear suppliers who will have suitable gears off the shelve.

Cheers

Stew

[websterz]

What is the bright orange light on the floor under the lathe?

[Bernd]

Really hot swarf! 

Bernd

[John Hill]

I think it is the sun shining through a chink in the floorboards!