Speed controller for Angle grinder

I have one of these:

https://www.screwfix.com/p/erbauer-eag900-115-900w-4-electric-angle-grinder-240v/763fv

I’d like to be able to slow down the speed for some jobs. Is it possible to make something to fit between the wall socket and Angle grinder plug?

It’ll be tricky. Anything that drops the speed will likely drop the power too and you’ll risk it stalling. Far better to just buy a new variable speed grinder. Having two is handy anyway, saves swapping disks.

Is it possible to make something to fit between the wall socket and Angle grinder plug?

It’s certainly possible to do that. I can’t see it (safely) making any difference to the speed of the disc though, unless your ‘something’ is a cheese sandwich and your slower speed is “stopped”.

Would a smaller disc work? Given the same angular velocity a smaller disc will have lower linear velocity.

In a word no and don’t try it. The machine is designed to operate at one speed with purpose made grinding tools. Changing to a lower speed could risk disc jams which can lead to horrendous injuries. Putting in a tool not designed for high speed and pressing the wrong setting could be even worse!

If you want slower speeds you could use an right angle drill that will have greater torque and flexibility for different bits. Great for drilling into tight spaces and easier than a regular drill sometimes. For sanding or polishing a more specialist tool might be better (and cheaper).

A few screwfix possibles:
https://www.screwfix.com/c/tools/drills/cat830704#category=cat830840

In a word no and don’t try it. The machine is designed to operate at one speed with purpose made grinding tools. Changing to a lower speed could risk disc jams which can lead to horrendous injuries.

Yes, but. Many companies offer angle grinders with variable speed controllers built in. I’ve got a Bosch. As long as you operate the attachment at the designed speeds, I’d don’t see a problem. You can build a speed controller using a dimmer switch of the correct type. Did that for my dremel.

If your grinder stalls is because you are putting too much pressure/using the wrong attachment which is clogging etc.

Be sure to video it.

Can’t afford to buy another tool. Its only for carving wood for a bit of fun.

You can build a speed controller using a dimmer switch of the correct type. Did that for my dremel.

What kind of dimmer switch would I need?

Also, if it doesn’t work, will it damage the grinder?

something like this will work

2000W Adjustable AC 50-220V 25A Motor Speed Controller Voltage Regulator PWM

What kind of dimmer switch would I need?

Also, if it doesn’t work, will it damage the grinder?

For a dremel, a variac or SCR based one. I put a fuse inline in case the dimmer released it’s magic smoke to protect the motor. I wouldn’t actually advise that for an angle grinder becuase it’s a far more powerful motor. Spend a few more quid and get one designed for higher demand motors, you can buy e.g. a router speed controller. They have circuits to flatten out the ‘pulse’ of the voltage that can damage motors.

I’m not sure what kind of wood carving you are doing but I don’t think an angle grinder would be a good tool for that. I can’t ever remember seeing an attachment designed for wood, except the fairly aggressive abrasives. Those probably wouldn’t produce the results you want.. If you have a drill, a set of grinding/burr bits would be a better bet

Chromolly – you get a variety of wood carving wheels of varying sorts.

You can buy discs with a chain saw chain/blade wrapped around.

Horrendous.

Chromolly – you get a variety of wood carving wheels of varying sorts.

Well look at that. I suppose I’ve never seen them becuase I’ve never looked. Or shopped for grinder wheels in places that have them. Look bloody vicious.
I’ve seen people carve wood with a chainsaw. Never seen a chainsaw wheel. The one I just looked at recommends 10-13k rpm. In which case just use the grinder as is. They are pretty scary the first few times you use one and you can grind right through metal panels and the like (ask me how I know) with practice you develop a light touch and feel for what you are doing. So you don’t go through. Very often.

Yes, you can do it. An AC variable speed drive is what you need (seen above). They might cost more than another grinder though! I would also be very carful with those chainsaw wheels, one wrong move and it could be trouble!

Speed Controller

Speed Controller

Made in Hong Kong and posted by a seller in Lithuania with photos showing US plugs and a 120V rating, claims 220V in the product description. Well, I’m totally convinced that that’s going to be BS1363 compliant and won’t burn the house down.

Why is this still a conversation? Sell your existing angle grinder and buy one that’ll do what you want to do by design rather than cocking about trying to make mains voltage do something it’s not supposed to do. An electric motor is not a light bulb and an angle grinder’s power requirement is tenfold that of a Dremel. The price difference on ebay between a Draper variable speed angle grinder and a Far Eastern speed controller that hopefully won’t kill your home electrics, your tools, or you, is less than ten quid.

Get on ebay and buy a Parkside 125mm grinder with built in speed control and
the nice long handle grip which will be much easier to control.
They are available for £40 including postage.
Speed controller on that type of electric motor has risks just doing the mwiring unless you make up a box with socket and flying lead plug which all adds to the cost.