24v dc motor powering a drill press

[peak4Participant @peak4]

If one types "mobility scooter motor" into ebay or Google and looks at the images of the labels, they all seem to have this strange wattage marking.
i.e. VxA is considerably less than the marked wattage.

e.g 2A 24V 250W, 3A 24V 270W or 11A 24V 950W

I guess the smaller ones are for 4mph scooters and the larger 950W ones are for the 10MPH ones.
I'm also guessing that there may be more info on web sites related to "Robot Wars"

The other well documented source for low voltage motors is ex-treadmills, though I have a 12v 1/4HP one from an Atco Lawnmower.

Bill

Looks like we were typing at the same time;

Dave (SOD), which is it, Great minds think alike, or fools seldom differ 

 

Edited By peak4 on 22/03/2019 17:17:17

[SillyOldDufferModerator @sillyoldduffer]

Looks as if Steve's Motability Motor isn't unusual in having an odd specification. Two more examples from ebay:

24V at 3A max is 72W, rather short of the 270W mentioned! However the label also mentions 'Class H', which apparently means the motor can be hammered until the winding reaches 180C.  Could mean, "270W until it gets too hot".

Another odd one:

This is 24v at 2.0 Amps = 48w. In addition to claiming 250W, the label also mentions 2/5HP, which is 298W. 

I don't know anything about the duty these motors are designed to deliver on a scooter. If the labels make any sense at all, they seem to imply that the motors are expected to trundle along slowly most of the time, but have to deliver much higher outputs in short bursts.

Dave

 

Edited By SillyOldDuffer on 22/03/2019 17:17:27

[Robert Atkinson 2Participant @robertatkinson2]

OK,

This is probably "specmanship" the 3A , 11A or whatener i probly the no load or minimum load current and is given so you can "calculate" a long battery life. I'll bet anyone it closer to 100A when pulling a 180 person uphill.

Robert G8RPI.

[Dave HalfordParticipant @davehalford22513]

Steve

I notice your drill press is a Startrite so not exactly junk. I've copied this bit below from lathes .co web site **LINK** – you appear to have an old un, probably intended for woodworking.

Startrite drilling machines (drill presses) were manufactured from the early 1950s, the original model, of which few details survive, having a most distinctive cast belt cover with the word "Startrite" arranged in a tall, narrow band down its front face. Four speeds were available, all set rather on the high side as standard at 480, 1020, 1990 and 4220 r.p.m. However, it is believed that the makers offered an alternative, slower set, more suitable for general metal working.

Whats the motor rpm? if it's 1430 you need a smaller motor pully set

Edited By Dave Halford on 22/03/2019 20:49:56

[Steve King 5Participant @steveking5]

Thanks Dave very interesting information its currently got a 1440 rpm motor fitted.

And this is the current set up

[Mike PooleParticipant @mikepoole82104]

The setup you have would suggest your machine is stock and it would be suitable for drilling steel up to a 17mm drill, the motor is 1/3 horsepower so power rather than speed may be a limitation, I would put a decent quality sharp drill up to 17mm in it and drill some steel, you may find you need to do nothing to the machine. The problem with speed controlled motors is that they reduce power as they go slower even if they maintain torque. Mechanical speed reduction keeps the power and multiplies the torque. If you really feel the speeds need to be slower then fitting an intermediate pulley can sort this with less trouble and more benefits than a speed controlled motor.

Mike

[duncan webster 1Participant @duncanwebster1]

Speeds on my Meddings are 500 to 4000, and that's a proper industrial job. As it has a 1/2" chuck, Mr Meddings must have thought that was the right speed, but I will admit to having drilled bigger holes with it. %00 rpm at 1/2" is only 65 fpm, so I wouldn't call it too fast.

[Anonymous]

I'd agree wholeheartedly with MikeP. The machine runs at the sort of speeds I use for drilling anyway. It doesn't seem sensible to replace the motor with one running at a significantly higher speed.

Andrew

Edited By Andrew Johnston on 23/03/2019 09:04:14

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