Rotary hammer vs cut off tool?

[NickG]

I am considering getting a battery powered tool for field collecting in limestones. Would a rotary hammer with a chisel mode be better than an angle grinder/cut off tool? If the latter, is it worth splurging for one that can accept a 7" over a 4 1/2" blade?

 

One advantage I imagined of a cut off tool is it might be lighter when hiking or climbing and making # cuts to chisel blocks out whereas I suspect a rotary hammer might do more damage to a rock face I'm trying to extract a fossil from. Any advice would be greatly appreciated.

[caterpillar]

In my opinion, a grinder will be more efficient because it is more precise and produces much less vibration. And the vibrations, it breaks the fossils.

The disadvantage of a grinder, is that during the cut you can cut a fossil that you haven't seen and you won't be able to put it back together because a piece equivalent to the thickness of the disc will be missing.

With a rotary hammer if you break it you can always put it back together...if you find all the ends!!

[FranzBernhard]

6 minutes ago, caterpillar said:

The disadvantage of a grinder, is that during the cut you can cut a fossil that you haven't seen and you won't be able to put it back together because a piece equivalent to the thickness of the disc will be missing.

With a rotary hammer if you break it you can always put it back together...if you find all the ends!!

Clearly a multi-purpose tool is needed !

Franz Bernhard

[hadrosauridae]

Be sure to think about the thickness of the fossil you are trying to extract.  Most angle grinders use a 4" wheel, which means you have less than 2" of depth you can cut.

[Fossildude19]

I have both tools.

 

Although my rotary hammer drill is new, and has only been used once, it was good for starting chisel cuts into shale/limestone faces, to be able to remove large blocks.

I use my angle grinder regularly. Not only is it good for cutting out blocks of fossils, but also for trimming finds in the field.  The rotary hammer, while good, is less useful, and uses much more battery power than my angle grinder. I have 2 - 4 amp/hour batteries, and ran through a fully charged battery in the field very quickly with the rotary hammer drill.

 

It depends on the rock you are dealing with. Sandstones and limestones are usually harder, and will take more effort to cut/hammer.

 

 

I would go for the angle grinder, personally. 

[NickG]

Thanks everyone. You've convinced me to go for the angle grinder. Will report back with how it goes.