vyv_cox
Well-known member
Not true of mine. I can reduce the speed to an extent that I can see the disc rotating, probably not much more than 100 rpm.
Angle grinder questions
- Thread starter Boo2
- Start date
Not true of mine. I can reduce the speed to an extent that I can see the disc rotating, probably not much more than 100 rpm.
Lakesailor
New member
.....and really, don't be tempted to use a cutting disc without the guard on.
I've done it. I used to as a matter of course.
But the guard will stop the grinder spinning around the disc because.....
.........one day the disc will snatch in a cut (the metal may move, like when cutting angle iron) and the grinder will be wrenched from your hand, almost tearing your thumb off and will spriral up into the air (still running because it was one with a "latch-on" switch) and plummet to earth, hopefully not landing on you or a loved one, with the disc still spinning at 6000rpm.
I was that soldier......
I've done it. I used to as a matter of course.
But the guard will stop the grinder spinning around the disc because.....
.........one day the disc will snatch in a cut (the metal may move, like when cutting angle iron) and the grinder will be wrenched from your hand, almost tearing your thumb off and will spriral up into the air (still running because it was one with a "latch-on" switch) and plummet to earth, hopefully not landing on you or a loved one, with the disc still spinning at 6000rpm.
I was that soldier......
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macd
Active member
Pronounced with such impressive certainty. I generally think very highly of your contributions here, Vic, but kindly allow that I might know more about my tool chest than you do. 3000rpm at its slowest? Cobblers.
PS: just seen your response to Vyv's post, regarding the specific grinder from Lidl. Humble apologies for misconstrueing the context of what you said.
However (and no reference to Vic's remarks) I repeat that there is no reason at all not to use a grinder for polishing if the revs can be reduced adequately.
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Lakesailor
New member
So how hard will you have to push on the polishing pad to drop the revs to under 1000rpm
when it's free rotating speed is 3000rpm - 12,000rpm
when it's free rotating speed is 3000rpm - 12,000rpm
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vyv_cox
Well-known member
Yes. The red rectangular object on the handle is the speed control. That's one of the ones I own and use most often.
macd
Active member
Indeed. If you read the PS to my last post (which crossed in the ether)...
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winsbury
New member
I have four tools in my box : small angle grinder, large ( in reality its a medium one if you were to compare it to the monsters the road menders use ) , a polishing machine and a buffer.
Grinders are great for cutting and grinding with appropriate discs and lots of personal protection - they can be lethal as bits not only fly off the discs but off the object being worked on too which also can get very hot indeed and sparks from metal working can cause fires.
The polishing machine looks very similar to the larger grinder but is offset by 90 degrees making it much easier to use for large flat areas ( gelcoat in particular with a lambswool bonnet and mild cutting compound comes up lovely )
The buffing machine was a complete waste of money - ( Halfords ) - it just about manages to buff a wax coat to a dull shine but is vastly underpowered to stop unskilled punters accidentally burning the paint/laquer on their cars.
The polishing machine has been worth every penny of the £80 or so it cost and Ive used it to do brightwork including bringing basic 316 steel to gleaming mirror polish as well as very fine work on paint and gel. There's no way the grinders would have the control to do this. They are however excellent at what they do and I wouldnt be without them - but - use the largest machine / disk you can - the efficiency is massively improved with larger disks and the work is done far faster. I use the small one only when its impossible to wield the big one due to space restrictions ( in the bilge for example .)
Grinders are great for cutting and grinding with appropriate discs and lots of personal protection - they can be lethal as bits not only fly off the discs but off the object being worked on too which also can get very hot indeed and sparks from metal working can cause fires.
The polishing machine looks very similar to the larger grinder but is offset by 90 degrees making it much easier to use for large flat areas ( gelcoat in particular with a lambswool bonnet and mild cutting compound comes up lovely )
The buffing machine was a complete waste of money - ( Halfords ) - it just about manages to buff a wax coat to a dull shine but is vastly underpowered to stop unskilled punters accidentally burning the paint/laquer on their cars.
The polishing machine has been worth every penny of the £80 or so it cost and Ive used it to do brightwork including bringing basic 316 steel to gleaming mirror polish as well as very fine work on paint and gel. There's no way the grinders would have the control to do this. They are however excellent at what they do and I wouldnt be without them - but - use the largest machine / disk you can - the efficiency is massively improved with larger disks and the work is done far faster. I use the small one only when its impossible to wield the big one due to space restrictions ( in the bilge for example .)
oldsaltoz
New member
I'm left wondering how the paint shop boys manage to use polishers at 1,800 RPM with cutting compound on a 9 inch foam pad?
The speed over the surface at the outer edge must be frightening, not for the faint hearted.
They do use a different machine for the final buff with the fluffy bonnet that a lot slower though.
Good luck and fair winds.
The speed over the surface at the outer edge must be frightening, not for the faint hearted.
They do use a different machine for the final buff with the fluffy bonnet that a lot slower though.
Good luck and fair winds.
BERT T
New member
FIRE! FIRE!
The one thing you have all forgotten to mention is when cutting or grinding steel with an angle grinder make very sure the sparks are NOT HITTING the legs or any other part of your trousers. I've seen many a pair of trousers go on fire from this.
The one thing you have all forgotten to mention is when cutting or grinding steel with an angle grinder make very sure the sparks are NOT HITTING the legs or any other part of your trousers. I've seen many a pair of trousers go on fire from this.
winsbury
New member
ianabc
New member
building steel boat
At the beginning of my steel boat building project , at a local welding shop, I was shown by the foreman, terrible photos of cutting injuries all caused by grinders.
Very sobering
And very kind as I have been most careful with the tool since then.
Many caused by lack of attention to details, such as un plugging when changing cutter blades.
I had one cutting blade fail.
At the beginning of my steel boat building project , at a local welding shop, I was shown by the foreman, terrible photos of cutting injuries all caused by grinders.
Very sobering
And very kind as I have been most careful with the tool since then.
Many caused by lack of attention to details, such as un plugging when changing cutter blades.
I had one cutting blade fail.
Niander
New member
Yes i forgot to mention they can set you alight
i did this during heavy engineering but then it was a "big" grinder
and when sparks are concentrated can set even overalls on fire and if i mention that the concentrated area was an area that is very dear to a mans heart!...
now that was a nice T shirt to own...
i did this during heavy engineering but then it was a "big" grinder
and when sparks are concentrated can set even overalls on fire and if i mention that the concentrated area was an area that is very dear to a mans heart!...
now that was a nice T shirt to own...
chrishelen
N/A
An old welder we had working for us on seagoing maintenance, used to take the guard off the grinders as a matter of course,12inch ones aswell
when i pointed out to him the errors of his ways he told me he did it because it (the guard) got in the way, couldnt work out why, he was a terror to work with, constantly setting fire to things. i was his fire watch on some ships we worked on. he set himself onfire at least once a week from grinding stuff with oily overalls on, great bloke. celebrated his 65th birthday on a trip to Russia by setting fire to his mate, accidently of course.
Conachair
Guest
The 1mm blades do a good job of cutting steel wire rope as well if you are doing your own rigging.
Plevier
Active member
Do you know the Nut and Bolt Store (aka Namricks) on Portland Road in Hove?
They keep a range of grinding and cutting disks (at good prices, not silly B&Q level) including special thin ones for stainless. Might be worth calling to see if they do anything for ali. (They also keep a pretty useful range of stainless nuts and bolts.)
If a grinding or cutting disk is eccentric I would bin it immediately.
macd
Active member
Is it just me or have VicS's posts disappeared?
machurley22
New member
How very peculiar.
DownWest
Well-known member
Long time ago, a mate worked with a sculptor. Used to cut ally castings up with an angle grinder. Lump of wax handy and dipped the disc into it before cutting. Stopped it clogging.
Never tried it myself, but he said it was easy.
Never tried it myself, but he said it was easy.
Keith 66
Well-known member
Of all my tools the angle grinders are the ones that i have had accidents with.
9" grinder with heavy sanding disc on, put it down on my leg just after i had let go the trigger, that went through overalls jeans etc like they were not there & gave me a nasty graze. Could have been worse!
Borrowed a 4" grinder from a friend because mine had blown up. it was a wreck with the wrong nuts on it but i thought "I onlyhave a little bit of grinding left to do", the disc burst at 10,000rpm. Quite exciting in the engine bay of a yacht. A big lump of the disc hit me in the face. Fortunately i was wearing a racal airstream respirator & the visor did its job. Expensive bit of kit but it paid for itself that day.
9" grinder with heavy sanding disc on, put it down on my leg just after i had let go the trigger, that went through overalls jeans etc like they were not there & gave me a nasty graze. Could have been worse!
Borrowed a 4" grinder from a friend because mine had blown up. it was a wreck with the wrong nuts on it but i thought "I onlyhave a little bit of grinding left to do", the disc burst at 10,000rpm. Quite exciting in the engine bay of a yacht. A big lump of the disc hit me in the face. Fortunately i was wearing a racal airstream respirator & the visor did its job. Expensive bit of kit but it paid for itself that day.
ffiill
Active member
Run out-take the wheel off and check the drive washer underneath which is usually loose and lifts off the drive shaft.
I recently bought one of Wickes own brand (see my cheap Chinese thread).
The washer on mine seats on the shaft and is sopped from spinning loose by little more than a shallow squared of groove groove cut in the base of the washer perhaps 2 mm deep which mates with the squared off shaft about 8 mm.
All that really stops the whole thing moving is presseure on the plate caused by tightening the securing nut.
I do not like it one bit
I recently bought one of Wickes own brand (see my cheap Chinese thread).
The washer on mine seats on the shaft and is sopped from spinning loose by little more than a shallow squared of groove groove cut in the base of the washer perhaps 2 mm deep which mates with the squared off shaft about 8 mm.
All that really stops the whole thing moving is presseure on the plate caused by tightening the securing nut.
I do not like it one bit