Grinding In Close Quarters

So I have a dilemma, I had a healthy assortment of grinders, surface tools, and of course the all mighty flap disc. However, what the best took for rapid metal grinding in tight spaces that you folks recommend?

I've seen mini flap discs for the 2 inch surface tool, but I've never used one and them seem pricey.

Specifically, I'm trying to dress welds in tight spaces.

 

Define “tight spaces.”
Flat surface in a 90° corner?

 

Both of these work very well...

 

The best tool and best abrasive really depends on accessibility to the area .
In general nothing abrades steel faster than a grinding stone or disk generally made of aluminum oxide.
The smallest diameter grinding disks are 4” diameter when new.
And it’s a great idea to save the mostly used disks for small areas.
Resin backed sanding disks are great to obtain a smoother finish.
They are available in many grits with 24 grit being the coarsest available.
They are available from 9” down to as small as 1-1/2” diameter and cut very fast but wear much more rapid than a grind disk.
Disks only work with right angle grinders.
For rotary work the bench grinding stone is king while the smallest stones can be mounted on die grinders.
In some cases the smaller disks can also be mounted on die grinders.
And yes here’s also where the various types of flap wheels come into common use.
Bur grinders cut pretty fast into non hardened steels and they too are usually mounted on die grinders or right angle die grinders

 

The air powered die grinder with the bits durangotang posted would be my choice in very tight spaces. But it depends on exactly what your situation is. Those bits can remove a lot of material pretty quickly. May not leave you with the the smoothest end product, like a sanding disc might.

 

The small belt grinder is very handy, but buy a bunch of good quality belts. Its like a file.
Burrs, I always get metal splinters in my hand.

 

If I have a tight spot like a corner where three pieces intersect then I use a die-grinder or don't worry about it (if not visible). Sometimes it's not worth dressing the weld.