What wrong with my angle grinder?

[MoodySabre]

I have a Clarke angle grinder - used for half an hour a year for the past 4 years. Lives in the dry garage when notin use.

Last year worked fine. This year nothing.

I have checked:
Fuse
power through the switch
power to the brush-holders
brushes - lots left
no apparent damage or corrosion to windings
nothing seized.

Any ideas other than a trip to Machine Mart to buy a new one?

I use this for a flap wheel to whizz the small patches of rust off the keel before treatment. Will the flap wheel work effectively in an 18V power drill?

 

[VicS]

I have a Clarke angle grinder - used for half an hour a year for the past 4 years. Lives in the dry garage when notin use.

Last year worked fine. This year nothing.

I have checked:
Fuse
power through the switch
power to the brush-holders
brushes - lots left
no apparent damage or corrosion to windings
nothing seized.

Any ideas other than a trip to Machine Mart to buy a new one?

I use this for a flap wheel to whizz the small patches of rust off the keel before treatment. Will the flap wheel work effectively in an 18V power drill?

Commutator?

 

[MoodySabre]

Commutator?

Looks OK - all bright and shiny.

 

[Sans Bateau]

Using a multimeter, check to ensure you have continuity between the the brushes and the wires in the plug. Has the flex fractured?

 

[Danbury]

If it has one of those safety switches that needs to be slid somewhere before it works... is that sliding where it should ? No muck stopping it ?

 

[MoodySabre]

I have checked the continuity from the plug to the brushes - OK when the switch is On. No secondary safety switch, nothing useful in the manual other than 'refer to Clarkes agent'.

 

[vyv_cox]

I had a similar problem with a detail sander that had had even less use than your grinder. I took it apart and could find nothing wrong. There was a capacitor(?) and I assumed that might have failed.

 

[lw395]

I would check whether it actually makes a circuit.
Unplug, switch on, measure resistance across L & N pins of plug.
Should be quite low, less than 100 ohms.

Brushes could be stuck, armature could have failed.
Also field coil wiring could have failed.
Last power tool I saw with similar issues was mains flex gone intermittent where it goes into the tool.

Do of course check the socket is live with another appliance.....

 

[lw395]

I had a similar problem with a detail sander that had had even less use than your grinder. I took it apart and could find nothing wrong. There was a capacitor(?) and I assumed that might have failed.

Start capacitor failed on my pillar drill after about 20 minutes use. Wouldn't expect one in a mini grinder, but I might be wrong.
Hard to test unless you have a capacitance meter, but I got a new cap on eBay for a few pounds.

 

[Lakesailor]

Just get a new grinder. Cheap as chips. Move on.

 

[VicS]

Start capacitor failed on my pillar drill after about 20 minutes use. Wouldn't expect one in a mini grinder, but I might be wrong.
Hard to test unless you have a capacitance meter, but I got a new cap on eBay for a few pounds.

There may be a small capacitor for interference suppression .. Totally different to the start capicitor in induction motors.

I had the capacitor fail in an old electric drill. It kept blowing its fuse though. I could not figure out what was wrong so I put a bigger fuse in. Nothing to lose. One day there was a fecking big bang. Investigated and found the capacitor had blown itself to bits. Removed the remains, problem solved, still in use 30 years later at an age of about 60 years

Just get a new grinder. Cheap as chips. Move on.

Probably the best advice but its annoying when things go wrong and you cannot fix then a little or no cost.

 

[MoodySabre]

Probably the best advice but its annoying when things go wrong and you cannot fix then a little or no cost.

That's what I feel - most things go wrong because of small things. I hate chucking things away and buying a whole new one.

Hey ho - stand by, bin.

Thanks for replies.

 

[jerrytug]

Well Moody Sabre have you checked that 230v is actually getting to the brushes? Work your way back from there. You have to test it live with the power on, the grinder in a vice in case it starts because of an intermittent connection. And tape or clamp the switch 'on'.
I bet it's a loose connection, worth an hour checking it properly surely?
This is the *PRACTICAL* boat owners forum by the way, to the person who says buy a new one.
(I just pulled a new £200 Dyson out of the neighbours's bin, the fuse had gone, sad really)

 

[FullCircle]

That's what I feel - most things go wrong because of small things. I hate chucking things away and buying a whole new one.

Hey ho - stand by, bin.

Thanks for replies.

I will add it to my pile of 'junk'. Will collect soon.

 

[lw395]

..... (I just pulled a new £200 Dyson out of the neighbours's bin, the fuse had gone, sad really)

I had a Dyson which blew a fuse, so I simply replaced the fuse.
It worked for an hour or so, then the fuse blew again.
So I replaced the fuse again, checked the motor was free to turn etc.
It worked for a minute or two, then had a serious attempt at catching fire. The armature seemed to have gone intermittently short.
However a new motor is not expensive for these things.

 

[alahol2]

My electric drill wouldn't start yesterday. Banged it on the ground in frustration a couple of times. Started and carried on for the rest of the day.

 

[MoodySabre]

Well Moody Sabre have you checked that 230v is actually getting to the brushes? Work your way back from there. You have to test it live with the power on, the grinder in a vice in case it starts because of an intermittent connection. And tape or clamp the switch 'on'.
I bet it's a loose connection, worth an hour checking it properly surely?
This is the *PRACTICAL* boat owners forum by the way, to the person who says buy a new one.
(I just pulled a new £200 Dyson out of the neighbours's bin, the fuse had gone, sad really)

Jerry - I have checked continuity from the plug to the brushes. I can't check it live without taking the brushes out. Even if 230v isn't there then I can't fix it. Screwfix £15.99 here I come.

 

[Heckler]

Jerry - I have checked continuity from the plug to the brushes. I can't check it live without taking the brushes out. Even if 230v isn't there then I can't fix it. Screwfix £15.99 here I come.

I suspect it could be the brushes sticking, check they move freely in the holder
Stu

 

[nigelmercier]

I suspect it could be the brushes sticking, check they move freely in the holder

+1

 

[Sans Bateau]

Jerry - I have checked continuity from the plug to the brushes. I can't check it live without taking the brushes out. Even if 230v isn't there then I can't fix it. Screwfix £15.99 here I come.

Woooooooooooow! MS! You've already got one cheapy which does work, I threw away a cheap angle grinder which failed after two or three uses and paid £35 for a Makita one. Buy cheap buy twice.