Workflow for cutting anchor rod from concrete

[yehor]

I want to cut off a couple of anchor rods (~10mm) that are embedded in concrete. I have never used an angle grinder for this purpose and I'm planning to rent one.

Can I use a cutting disc to cut the rod at an angle a few millimeters into the concrete, or will I ruin the disc? Or should I first cut the rod above the concrete and then use a grinding disc to grind down the rest? I’m thinking if so, it will protrude 5mm, grinding this down must take forever?

I would like to do this as quickly as possible.

I would also like to know how to choose the disc's thickness.
Any other tips are welcome. The surface will later be repaired and painted, but I also want to minimize this work.

 

[proffsrik]

I want to cut off a couple of anchor rods (~10mm) embedded in concrete. I have never used an angle grinder for this purpose and was thinking of renting one.

Can I use a cutting disc to cut the rod at an angle a few millimeters into the concrete, or will I destroy the disc? Or should I first cut the rod above the concrete and then use a grinding disc to grind down the last bit? I think it will otherwise stick up 5mm, grinding this down must take forever?

I would like to do this as quickly as possible.

I would also like to know how to choose the thickness of the disc.
Any other tips are welcome. The surface will be repaired and painted afterward, but I want to minimize this work as well.

Regular cutting discs and grinding discs don't bite very well into concrete. However, they cut through iron like butter (almost). Cutting an M10 threaded rod with a cutting disc takes under a minute. You can also cut them with a regular hacksaw. (it's actually quite fast too)

If it were me, I would have:
1. Cut the rod with a hacksaw or angle grinder with a cutting disc.
2. Chiseled a little around with a chisel and hammer.
3. Ground down the exposed metal a few mm below the surface with a grinding disc on the angle grinder. For the geometry, a smaller disc is better here.
4. Repaired with concrete filler. Combimix has one that I think works well.

 

[fribygg]

If it's just a couple of pieces, you can use a chisel,
If you want to use an angle grinder, a cheap one from Biltema or Jula will do for your purpose. For 3-400kr, you can get a 125mm grinder that's good enough for home use. It's hardly worth renting when you can get one yourself and a handful of grinding/cutting discs for under 500kr.