Mini Lathe Motor. Again.......

[Stilldrillin]

Well.....
I'm fiddlin' with it, again!   

As many of you remember, I recently sorted my mini lathe.......
Amadeal controls, Chester motor, (to fit inside the bed casting recess), lower belt ratio...   
Here, if you have the time.....  http://madmodder.net/index.php?topic=6602.0

It has run very well. Lively, powerful. All I wanted it to do for me. 

The Maiwald Makeover had stalled, due to cylinder/ piston doubts...... So, I decided to rough out the twin 5" flywheels.
Rather large for a mini, but shouldn't be a problem. Probably!

Suddenly, for the first time with the recent mod, the chuck stalled......... Instantly, the motor gave a little pop! 
I whipped the tool free, and the chuck started again, but didn't sound right....... Oh. Bugga!! 

Surely, it should be allowed a stall, or two?? Summat's still not right........ 

OK!! ....... Guess it's time to mod it, to take one of Amadeal's larger/ more powerful, 550watt motors. (Instead of Chester's 400w).


I ordered the new motor, on Tuesday. To be delivered Friday....

Friday came...... But, the motor, didn't! 

Rang Amadeal..... "It should be there!" 

After a couple of mins, the phone rang! The Carriers have taken it to their Hub................ In ABERDEEN!!!!! 

I live roughly in the middle of the country. The motor passed within a couple of miles, on it's way to the North of Scotland!! 

It's no use shouting at the seller. It's not his fault......      
But, why do I mostly laugh, when this sort of thing happens? (And, it does happen.... Regularly).

So.... I waited. Did a bit of spacer milling...... Until Monday......

Delivered, finally, early afternoon......... 



Smashed........................





                   

So........ I picked up the phone, again......       

David D

[dsquire]

David

Sometimes it seems that if it wasn't for bad luck you wouldn't have any luck at all. I know what it's like. You want to grab someone but there is no one to grab that will do any good. You can yell and scream through the phone but you can't find the clumsy oaf that destroyed your motor after taking it on world tour. Best to just grab a pint and sit back and breath. There are many different ways to try our patience. This is just one of them.
 

Cheers 

Don

[andyf]

David,

Putting it very mildly indeed, that's somewhar disappointing|

Maybe some good might come out of it, though. If Hugh at Amadeal doesn't want the broken one back, you could perhaps keep it for spares. Might be useful, given the rate at which you consume motors.

Slightly off-topic, because I don't think you have the room to do it, but I squeezed in a external fan on the end of my motor. The fan runs continuously when the lathe is plugged in to thee mains, whether ot not the motor is turning. http://andysmachines.weebly.com/motor-cooling-fan.html .

Andy

[hopefuldave]

While you're in there, David...

The external fan's a good idea[1], particularly if it stays on all the time to cool it down between runs, and I've noticed that one of the manufacturers is now adding a second fuse in line with the motor - for the 550W a 5A slow-blow (marked "250V 5AT" or "T5A") would probably be about right, this should protect the motor and controller if/when it gets stalled. Total cost a couple of quid from Maplin or similar? *Buy spare fuses!*

The reason they blow when stalled (for those who don't know) is that the back-emf from the motor armature cutting the magnetic field disappears (there being no relative motion) so all that's resisting the current is the motor DC resistance - only a few Ohms - with anywhere up to 180V applied to the armature... Most of the controllers have a current-limit setting (and some a "horsepower resistor") intended to tame this behaviour, but they used to say a transistor often fails protecting the fuse...

Just my Ape knee's woof,
Dave H. (the other one)

[1] a 2-litre fizzy pop bottle makes a great heat-shrink sleeve to attach a computer fan's mounting plate/box to the motor body...

[HS93]

Have you thought of going three Phase , I changed mine you can get a inverter for about £75 there have been some nice ones going on ebay at £50 recently the motor is the same sort of price and you get a more built proof set up and get away from the Chinese controllers I am doing my mill next as I have found the Lath so much easier to use.

Peter

Have a look on hear  for inverters  http://www.homeworkshop.org.uk/

[Stilldrillin]

Don.
Thanks for your sympathy. Chill I think, is the phrase......
I'm much too old these days, to get too excited over what now seems to be perfectly natural occurrences! 

Andy.
Disappointing? Yes!
But, on the other hand....... New opportunities!!

My spares pile is growing, monthly!

I love the fan idea, but, there's hardly enough room for a motor, inside my bed casting!
I'd only been machining a few seconds. Just settling into the feel of the larger work..... So, overheating (as such), wasn't the reason.

Dave.
Your Ape knee's woof, sounds good to me!

Peter.
All that sort of thing is beyond me!
I have to work with what plugs into what...... Or call Dave Bluechip.
In all honesty, I've tried his patience too often, since we met, on here....... 


It's the instant blow, which is bugging me.......

I have noticed. Chester's motor is labelled, 180volts........ Amadeal's says 230volts.
I guess I've been feeding a bit too much, into too little??
It was good, while it lasted!



Continuing.

The new, new motor arrived around lunchtime, the following day. No problem this time! 


**Please note**.
 I have nothing but praise for Amadeal, during this adventure. And also, my previous ones! They always give superlative service. I cannot rate them highly enough.......



The new motor is too long for the bed recess. Needing spacing rearwards by 2"...... Luckily, I've got the mill to work with.

A pair of 40mm dia aluminium spacers. Faced to 2" oal........





Drilled through 6mm........




A pair of elephant's legs, standing on the motor cradle.........




Fixed a plate, to move the motor height positioning screws, 2" outward........




Just a nice amount of clearance.......




But, there's a problem!
The top run of the belt passes straight through the part of the casting containing the leadscrew for/ rev indents.........



So, I chopped it away.........




To be continued.....................

David D

[andyf]

It's the instant blow, which is bugging me.......

I have noticed. Chester's motor is labelled, 180volts........ Amadeal's says 230volts.
I guess I've been feeding a bit too much, into too little??
It was good, while it lasted!

David,

The online manual for KB controllers says that the KBIC/KBLC 240s put out 180VDC, so I doubt that your old motor was being overfed.

I use a KBIC240 to control a 220V treadmill motor and it works fine. I am no electrics exper but 180V is only 82% of 220V, so maybe the max you can get out of the new motor will be less than 550W . I don't know how to work out how much less. My treadmill motor is 2HP and even if I only got 1HP out of it, that would be more than enough for what it does.

You seem to have room for an external fan, now the motor is no longer hiding under the bed. Computer fans are cheap, and there's usually an old 12V wall wart lying around the house looking for something to do.

Andy

[Stilldrillin]

Andy.
At the last incarnation, I was so fed up with unknown, (by Dave), possible control box problems.... I swapped the whole lot for an Amadeal assembly.





Unfortunately, I fitted the Chester motor, 'cos it was the only one which would fit into the recess........

Incidentally, the fan in the 550w motor is an alloy, multi bladed one. It makes a discernible draught, and not just at peak revs!

I intended to swarf protect the motor, by surrounding the brush end with an open ended plastic sleeve........ Which, of course would also house an external fan. 

David D

[Stilldrillin]

Continuing......

I had to re route the power input. Cos the motor was now in the way.......




Marked out the three quadrant positions, and dimpled with a 90dgr countersink.......




I then filed the cast boss, concentric with it's M5 bore. It finished at 8mm dia.

I could then turn a 90dgr peg, with an 8mm bore.......




And, made up a spring loaded plunger........




Click, click, click..... Works a treat!

Though the lower left indent needs to be a little larger, due to the weight of the handle.....




Just needs a tidy up.......




Not had much time to give a good work out. But, it's looking good, so far.......




Thanks for watching!

David D

[sbwhart]

Looks like you sorted that Dave 

Stew

[dsquire]

David

After all that fine work getting it shoe-horned in there so neat it dam sure better work just fine.  Looks like a great job from over here.

Cheers 

Don

[OldMetaller]

Great work David!  Also, full marks for staying so calm, I would have been climbing the walls long ago!

Regards,

John.

[Stilldrillin]

Stew, Don, thanks for your kind comments! 

John, you know my climbing days are long gone! I've long ago accepted the setbacks, as part of the pain/ pleasure of my hobby. Some people only build engines! 



Right! .... This here cooling fan.

Here's the motor side view........




And the end......




The motor is 80mm dia.
So, I sawed meself a piece of 70mm square mdf. Seems it will be the best size to hang off the underside of the chip tray, and clear everything.

So, I ordered this one.......   http://www.ebay.co.uk/itm/280932791547?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Found me a long redundant wall wart.......




Plugged it in, and attached it to a meter, to find which is + and -.
Noticed it was reading around 23volts, (50v scale). Is this normal? 

Or, should I bin it, and buy new?

David D

[philf]

Found me a long redundant wall wart.......




Plugged it in, and attached it to a meter, to find which is + and -.
Noticed it was reading around 23volts, (50v scale). Is this normal? 

Or, should I bin it, and buy new?

David D

David,

Your wallwart is almost certainly unregulated and the output voltage will fall when loaded. You really need to connect the fan to the wallwart and then test the voltage. The fan is unlikely to draw 1.25A so I'd expect the voltage to be higher than 12v.
 You could always connect a resistor in series with the fan to drop the voltage a bit.

Cheers.

Phil.

[andyf]

£1.78, with the shipping! Money's no object with you, is it? 

If it's got three leads, one of them will be for a tacho and can be cut off short, once you have established which it is. If it has a red and a black, those are probably the ones you want. Computer fans won't usually run in reverse, so try your + and - from the wall wart both ways. As the fan blows in one direction only, position it so it doesn't fight the motor's own fan when the motor is running forward, which will be most of the time.

My motor's fan was so weedy that I had to set up a smokescreen with my pipe to find the direction of the draught.

Andy

[Bluechip]

I got a 230V 70mm Box Fan doin nowt here ...
 
No wall-warts, no resistors, no voltage regulators, no nowt needed .... 
 
Specially formulated to dangle direct off the National Grid ... 

And Clinically Proven to boot .... or it can be if you want it, I'll squirt some juice into it, think it's OK though.
 
Any good 2 U
 
Dave
 
 

[Bluechip]

£1.78, with the shipping! Money's no object with you, is it? 



Andy

Just noticed this ....
 
          
 
Sarky bu99er ....
 
I'm proud of you ... You're showing promise, in danger of catching up with me ... 
 
Dave

[Ross]

A job well dove David! I hope this one lasts!

[Stilldrillin]

Phil.
Thanks for an explanation. But, when you start talking about a resistor, that's Mr. Chip's territory.
To me, it's either ok, or not...... We'll see.......

Andy.
I was (thriftily), raised in Yorkshire, you know!
I thought that was quite enough to pay, for summat that might not survive to see next morning.

Love the smokescreen idea. But, I'm too tight to start smoking now........

Dave.
I wondered where you were!
Nah! Leave the fan where it is. Thanks! ...... You don't need to come traipsing up here, just yet.

Wait for the mushroom cloud, as usual...... 

Hi Ross.
Thanks Mate! 

Get yerself over here, soon, and twirl some handles.......... 


Thanks Lads. I needed a smile.........

David D

[andyf]

..... Andy. I was (thriftily), raised in Yorkshire, you know!

David, I was born in Lancashire, where they say a Yorkshireman is like a Scot shorn of all generosity.

My father-in-law was a good example. He and others owned a medium sized engineering firm, and reckoned that if some sophisticated used machine they had bought hadn't paid for itself and got into profit within two weeks, they hadn't bargained hard enough.

Andy

[Stilldrillin]

Well....... The fan arrived, "instantly"! 

It only took 20 hours from Middlesex. And, the seller had already posted feedback. 

Don't know about you lot. I never post for a seller, who can't say "thank you", for my payment received.


Anyroad! I wired the red and black wires to the wart, and it blew, (air), like a good un!

No need to start smoking, Andy!   

After an hour continuous, I decided it might just survive assembly....... 

David D

[Stilldrillin]

Hmmmm...... Almost 4 weeks gone, and no obvious progress...... I'm watching paint dry, at the moment. 

The motor set up has been tried over a couple of projects.
All has gone well. It's pulling like a train..... Double header!



I folded up a 70mm square duct, for the fan.......




"Nailed" it together with panel pins, between two pieces of wood........




And, soldered together......




Snipped off the excess lengths........




The fan's a nice sliding, stay in place fit........




Bunged up the lower gap with foam, glued inside.......




It locates, with magnets, a bit like this.......




And this..........




Andy was right about the wind direction...... There's a draught out of both ends, when the motor's running! 

The motor fan is angled to draw from the pulley end. So, this addition is going to be an extractor fan........ 

Awaiting some better, nimmydimmy magnets, and a quick wiring session. Then another rebuild will be completed!

Until next time....... 

David D

[krv3000]

well dun

[Stilldrillin]

Thanks Bob! 


Well, it's done!

Painted. Wired. Positioned. Operating......... 

Just needs a pelmet, or something, to keep the swarf off the connector block. 




David D

[DMIOM]

.....Just needs a pelmet, or something, to keep the swarf off the connector block.....

David,

could I just suggest, whilst you're in "pelmet mode" it might be worth looking at the drive end of the motor as well? As I recall, you mentioned that the airflow was inbound at the pulley end, and from the belt shot above, it made me wonder if one of the suction slots might be exposed....

Dave M