Thread: DIY power feeder

Use a stepless switch and motor from an overhead fan?
Attach a drive belt to the axle of the motor to drive the rollers?
Wolffie

I think it could be done quite easily if you could find a source of electric wheelchair motors at a suitable price. Someone sold a fair number individually and in small quantities a while ago on ebay, prices ranged from $50 to $70 each.

Motors can run to about 1/2 hp each, and have an integral worm drive gearbox, tacho output for speed sensing/control, and an electromagnetic brake. They operate from 24V and have a regulated speed range from 1 to about 40 RPM in forward and reverse. Worm drive has a positive drive which will provide a basic antikickback function, up to the point where the drive roller looses traction and allows the material to slide back under the roller. With Wolfies suggestion of a ceiling fan motor, these motors are fairly easy to stall or wind back, and don't offer any real constant speed capability.

It might be possible to get an older chair, with 2 motors, contoller, usable battery pack and charger for maybe $100 or so. This would give you all the components you need except the mounting frame and drive roller(s). In that bracket, I'm thinking about an older chair with a damaged or unsuitable frame, where the drive system is old enough to not be considered suitable for transplant into a new frame.

I used to maintain these units so know first hand what their capabilities are. I actually used to have a couple of complete systems stored in the workshop waiting for me to invent a use for them, but they got tossed before I developed an interest in woodwork.

Try Oatley Electronics for low voltage high torque motors:

www.oatleyelectronics.com

The SCD2 looks particualrly interesting, it drives a rubberised wheel, as found on scooters...

The trouble with these low voltage high toque motors will be a power supply, they normaly run on DC and draw huge amount of amps.
The 24v ones at Oatleys are rated at 27amps... you ever seen a power supply that can support 27A at 24V?(the price will really scare you...)it'll be a lot cheaper to buy a proper power feeder.

The only economical way you could do it would be to use a decent 1/2hp variable/selectable speed 240V motor with a reduction gearbox to decrease the rpms and increase the toque.

By the time youi find and modify a suitable motor and then fabricate a suitable mounting system which allows you to adjust it uip and down, in and out as well as skewing, canting and tilting it it would be cheaper to buy a commercial unit.

Mick

I looked at the idea very carefully before I went and bought a small power feeder from Carbatec.

Originally Posted by Harry72

The trouble with these low voltage high toque motors will be a power supply, they normaly run on DC and draw huge amount of amps.
The 24v ones at Oatleys are rated at 27amps... you ever seen a power supply that can support 27A at 24V?(the price will really scare you...)it'll be a lot cheaper to buy a proper power feeder.

The only economical way you could do it would be to use a decent 1/2hp variable/selectable speed 240V motor with a reduction gearbox to decrease the rpms and increase the toque.

What?

The motor I referenced is rated at 100W.

at 24V, that would be just over 4 amps. - 4 x 24 = 96W

did you get 27A @ 24V from? - thats the same as 650W - almost 1hp - far beyond the legal power limit of electric bicycles (200W)

100W is well within the realms of reasonable power supplies, even a battery could do the job if need be.

The smallest commercially made power feeder is 1/4 hp so I expect you need to aim for that power in whatever motor you use. But keep in mind that a typical motor is only 60% efficient.

Because of inherent inefficiency a true 1 hp motor uses about 1100 watts so a true 1/4 hp motor must be about about 275 watts. So a 100 watt motor just may not have enough grunt to do the job reliably. It would be a real PITA to build a feeder and then find its too gutless to be practical.

From memory my feeder usually runs at about 6 metres a minute (the speed is adjustable via gearing changes), so that gives you some basis on the amount of reduction gearing that may be necessary.

Originally Posted by journeyman Mick

By the time youi find and modify a suitable motor and then fabricate a suitable mounting system which allows you to adjust it uip and down, in and out as well as skewing, canting and tilting it it would be cheaper to buy a commercial unit.

Mick

I agree entirely.

When you have a real good look at a proper power feeder you will find they are a very complex tool to fabricate as a DIY project

Originally Posted by zathras

What?

The motor I referenced is rated at 100W.

at 24V, that would be just over 4 amps. - 4 x 24 = 96W

did you get 27A @ 24V from? - thats the same as 650W - almost 1hp - far beyond the legal power limit of electric bicycles (200W)

100W is well within the realms of reasonable power supplies, even a battery could do the job if need be.

The motor I looked at oatleys is a 500w its rating is 27A
your idea of a 100w motor would not work, it will not have enough guts and will draw more than 4amps if loaded this hard.

And it is out of stock!

thumbs up for all the input.

I might be able to swing the extra $$ for a proper one form Ctec. They have two models, 1/4hp and 1/2hp. Is the smaller unit powerful enough to use with bandsaws and tablesaws, say cutting 2.5"-3".
What do you guys think, is the bigger (and heavier) model worth the extra money?

Fatty

I've got the small carbatec one and its great.
It works as well as any of the large 3 phase industrial feeders that I've used.