Using a Rotary Hammer

[cosmo]

I am looking to buy a rotary hammer and am trying to figure out what I need. Having not used one very much I have a few questions.

What is the best type for up to 2" holes?

Do I need a certain type (sds plus, max, spline) to use a core bit?

When using a core bit, is it done in the hammer with rotation mode?

Thanks

 

[DAWGS]

Bosch, Dewalt, and Milwaukee are my brands of choice. I would go with a 1-1/2 spline or SDS plus. Core drills work best for 2'' core holes, but we also use a core bits for our rotary hammer and it works OK as long as you keep some water to it when using for concrete. And yes you leave it on hammer when using it.

 

[Rewire]

I have a Hitachi and it works well up to a 2in dry core bit.

 

[Dennis Alwon]

I am looking to buy a rotary hammer and am trying to figure out what I need. Having not used one very much I have a few questions.

What is the best type for up to 2" holes?

Do I need a certain type (sds plus, max, spline) to use a core bit?

When using a core bit, is it done in the hammer with rotation mode?

Thanks

SDS is fine but I have a spline Bosch rotary hammer. You would use the core bit in the rotary mode which automatically includes the hammer mode. The hammer only mode is used for chiseling.

I drive ground rods and drill holes up to 2 9/16" with it. Big enough for a 2" PVC pipe.

 

[ultramegabob]

I have a milwaukee spline drive and a Hilti SDS max, both are excellent, but I havent touched my Milwaukee in a couple years, I really like my Hilti and I have more bits and attachments for it.... Buy a tool large enough to do what you want it to, dont worry if you cant afford to buy all the bits you need right off, you can usually rent large bits and just add it to the cost of the project...

 

[quogueelectric]

Hilti by a mile I have used all brands in the last 35yrs and There is no equal to the hilti line You get what you pay for.

 

[cschmid]

Now it really depends on what you are going to do with it..I used to own a Hitachi and now own a makita..I have used hilti and several other brands..If you want to do 2 In holes in electrical vaults and similar installations then buy a rotary hammer you will need the beef..the weight of the rotary hammer does not make it an everyday user friendly tool..If you want to drill small hole through concrete block then buy a SDS chuck hammer drill they are normally only rated for a 1 1/4 hole and run around 350 Dollar..the rotary hammer on the other hand is about 850 plus dollars..Just my 2 cents worth..

 

[mdshunk]

Survey what you can buy as far as bits locally, and pick your chuck from that. Just picking something off the cuff might cause you to hate yourself for the life of the rotohammer.

I use a spline drive rotary hammer, and I have an adaptor to go to regular SDS. This setup allows me to do everything from 3/16" Tapcon holes all the way up to a 6" core bit, if need be, with the same tool.

 

[Huevos]

Survey what you can buy as far as bits locally, and pick your chuck from that. Just picking something off the cuff might cause you to hate yourself for the life of the rotohammer.

I use a spline drive rotary hammer, and I have an adaptor to go to regular SDS. This setup allows me to do everything from 3/16" Tapcon holes all the way up to a 6" core bit, if need be, with the same tool.

I picked up a DeWALT D25551K HD spline drive off ebay for $250 shipped. I also picked up an SDS adaptor as well as an adaptor for 1/4" bits. Pretty much covered but I usually use my smaller Bosch hammer drill for 1/4". One thing I learned. Buying the Roto Hammer is just the beginning of spending money. You'll have at least that much invested in bits and adaptors before you're done.

 

[macmikeman]

If you guys think rotary hammer drills get expensive, try buying a real coring drill. Now them bits for that thing cost me some dough..

 

[mdshunk]

A word to those just getting into buying roto-hammers. Buy 4-cutter bits, whenever possible. They last much longer, track nicer, and won't "jam" in cracks like 2-cutter bits will. The price premium for 4-cutter bits is hardly anything.

Oh, one more thing. The core bit shafts are pretty much brand specific. You'll have to figure out what brand of core bits you're most likely to buy, and get the shaft(s) for that brand, unless you want to buy a new shaft every time you buy a new core bit.