Cheap Angle Grinder

[joegib]

Just picked up a cheap 4 1/2 inch (115mm) angle grinder in Maplins for £9.99 — illustrated here:

www.maplin.co.uk/Module.aspx?ModuleNo=219340&C=Maplin&U=SearchTop&T=angle%20grinder&doy=22m11

It's branded "Rolson" and at that price is almost certainly a far-eastern import (Indian?). Motor is rated at 600Watts and the build quality seems decent — the gearhead is a metal casting and the wheel guard is a reasonable guage pressing some 1/32- 1/16 in. thick.

Frankly, I bought it for cannibalisation to use:

1. The motor section to drive a toolpost grinder.

2. The gearhead to make a right-angle adapter for my vertical miller (not sure whether this is feasible though).

3. The wheel guard for use with the T & C grinder I'm building.

Can't speak to its long term reliability in its proper role but at 10 quid I thought it was worth a punt.

[abby]

I bought similar 4 years ago and it is still working well , my wolf grinderette over 60 quid many years ago didn't last a year - it was nicked LOL!

[SteveW]

Joe,

Not sure using a 600 watt serial wound motor is a good idea for a tool post grinder. You're talking about nearly 0.8 horse power. The bit you really have to watch is serial wound motors go around a lot faster than the nominal 3000rpm top end of most grinder wheels.

One point with these cheap angle grinders: don't be tempted to get one of those angle grinder holders and turn the thing into a useful little cut-off saw. It is a good idea but the holder I got from Screwfix couldn't possibly hold the grinder safely enough to use. The far too simple three/four 8mm set bolts pinching on the right angle gear box just ain't good enough. In my case it was a Bosh unit with a plastic g/box.

In the end I made a plate that screwed to the gear box and holder.

[steam4ian]

G'day Steve,
I have one of those grinder adapters, works OK .
For mine the 8mm bolts screw into the threaded holes for the handle; a bit more secure than just clamping. Thought of an unrestrained AG bouncing toward you is just to much.

Regards,
Ian

[joegib]

Thanks for the advice SteveW.

Yes, I'd agree that using a series-wound motor with a grinding wheel of significant diameter is very risky. What I have in mind is using it with grinding points of 1 inch diameter or less, mainly for internal grinding of morse tapers and suchlike. These wheels need high revs so they're built for it.

I've got a cut-off wheel adapter of the kind steam4ian mentions. As he says, the adapter mounting bolts screw into the handle holes to something like 1/4 — 3/8ths inch depth so the set-up's pretty secure. Even so, I'll be very cautious. The first angle grinder I bought was an 8-inch job that always seem to want to go into a gyroscopic orbit of its own. I was happy to trade that in for a 4 1/2 inch job!

[ron]

I used to use angle grinders a lot when I was doing classic car resto, basically like most things, you get what you pay for, the expensive ones last much longer but whether it's worth spending £60 for a good one when you can buy half a dozen £10 ones is doubtfull, only thing I would say is if you use them a lot buy at least two cheapos, because they always pack in at the most inconvenient time.
Ron