IF IT AINT BROKE DONT FIX IT

[Lazurus]

Being a handy sort of chap, after 15 years of heavy use I decided to change the bearings on my Creusen slow speed grinder, I duly took it to bits, removed and replaced the bearings without a hitch. in fact it is a very simple machine when you get to the innards.

I put it all back together - and I just cannot get it to run, the shaft is spinning freely and smoothly but when turned on the motor grumbles and no movement, it sounds like the motor is jammed or stalled, I tried spinning by hand to get it going, nowt........
No idea what to try now should have left it alone with the rumbling bearings. Lesson learned. (hammer)

 

[sunnybob]

the first and most likely is the start capacitor. But normally if you spin it by hand it will pick up speed.
Next is motor brushes, have you checked that BOTH of them are clean, positioned properly and the wire is not shorting out to the body or crimped under a spring?
After that have you got the mains cable leads tight? a loose connection can cause this fault.
Then its the trigger /switch.

 

[Lazurus]

will give it another look tonight, I fear it is something to do with the reassembly.........

 

[AES]

Just a question re motor brushes. I thought most, if not all, bench grinders have synchronous motors, correct? If so, am I also correct in saying that unlike "universal" motors, synchronous motors (aka squirrel cage or moving pole ??) don't have brushes. Or am I up the chuff here?

Also, I THINK I'm right (rpt only think) that if it's a synchronous motor there should be a great big thick copper wire from the field coil, and IF the motors turns freely without power, it's that copper wire that makes the motor start. Or am I (again?) off course?

 

[CHJ]

Rotor in the wrong way round?

Did you 'clean up' the rotor by any chance?

 

[Lazurus]

Well it was a combination of poor assembly - rotor off center and a failing capacitor so all good now, I ordered a new capacitor from Fleabay for a tenner with free delivery as from the parts supplier it was 12.99 plus 12.50 P&P!!!!!!! How can they justify that?

 

[sunnybob]

They dont have to justify that. If you dont want to pay, they dont care.
But was it an overseas shipment? sometimes usa stuff gets into a uk search.

 

[Lazurus]

No in the uk, I suspect it is a blanket charge, however a bit excessive on a small capacitor in a jiffy bag!

 

[Lazurus]

I don't believe it (as someone says) got the darn thing running smoothly put the 101 bolts guards bits and bobs back on, only to realize that I have put the central cover on the wrong way round so the switch is now at the rear....... Too much to dismantle it all again so it will have to stay..... some time it doesn't rain............

 

[sunnybob]

its called a learning curve. Sometimes its steep.
but you fixed it, thats all that counts.

 

[novocaine]

surely "if it ain't broke take it apart until it is then fix it" is a better approach. or is that just me.

 

[sunnybob]

yup, its just you.
your title just isnt snappy enough, even if it is more accurate. (hammer)

 

[novocaine]

If it can't be fixed with a bigger hammer then it's an electrical problem?

 

[offanonone]

If it moves and shouldn't - Gaffer tape

If it should move and doesn't - Big hammer

 

[Phil Pascoe]

If it moves and shouldn't - Gaffer tape
If it should move and doesn't - Big hammer

I used to work with a very good mechanic who was taught as an apprentice that everything he put back together should have either coppaslip or locktite on it.

 

[Lazurus]

well couldn't leave as it was with the switch at the back so I did change it, added the new capacitor which turned up this morning, now as smooth as silk again and runs a dream.... perseverance pays. lol

 

[Jonzjob]

You could always have stood at the back and reached over it :? That way the switch would have been at your front :mrgreen:

 

[sunnybob]

Like the s£&t for brains that designed the wetstone sharpening system jet sell. The on off switch can only be reached by leaning over a turning wheel.
This man done it right. Well done.

 

[Lazurus]

Guess it must be one of those weeks, the belt has failed on my Scheppach HMS260, so I gets me a new belt, bit of a bargain at less than half the price of NMA - so I fit it feeling very chuffed with myself, fire it up initially alls good, then smoke comes from the belt cover...... So I strip it down and find the small (10p) circlip has failed which holds the belt pulley on allowing it to slide along the shaft and rub on the belt housing which in turn melts the pulley side wall. So now a new pulley is needed at £40, all for a 10p bl00dy circlip.......... so that's 2 of the 3 as things come in 3`s!!!!!!!!!