Question about Hammer Drills, their bits, and adapters

Mike, Thanks for the info. Maybe I can find an "dead" Bosch deal like you did. I have never heard of "expanding grout" but it certainly could be useful.
Greg
 
MikeInOr said:
I picked up my Bosch SDS plus class rotary hammer for $40 because it didn't run. It took me all of 5 minutes to change the brushes once the new set came in. It works perfectly now.

It takes me 30 minutes+ to drill a 1 1/8" hole 6" deep in cured concrete with my Bosch. 1 1/8" is as big as my drill is rated for. I wouldn't try to go bigger with my Bosch, it would take forever. This was with a good Bosch 4 cutter bit and the drill got VERY hot. I doubt a HF drill would have held up for this job.

It took me about 6 hours to drill these holes in the slab I want to get rid of:
...
My Bosch rotary hammer is perfect for drilling holes in concrete and rock to mount stuff with lead wedge nuts. Which is what I really bought it for.
Click to expand...
Mike in Ore,
Again thanks for your advice. Following it, I too got a used Bosch Bulldog on eBay (for $80.) It came with a bunch of drill and chisel bits and ran okay. But something in the SDS chuck was messed up, the collar would not slip up to lock the bit. This really slowed down my effort on my first hole, but that was just hard clay, no concrete.
Then I ordered an $8 Bosch chuck rebuild kit (everything from the spring to rubber tip.) Problem fixed.
Yesterday I dug the 2nd of 3 holes for my antenna masts, this one a 12x12x28". As expected, a few inches down I encountered the buried drain ditch, you can see its concrete sidewall in my attached photos. Between the clay and the concrete, the whole hole took about 3 hours of drilling, chiseling, and bailing out the pieces.
Today I filled the hole with 200 pounds of Quikrete holding my half-"PostMaster" mounting plate into position.
Tomorrow or Tuesday I hope to do the final hole. No concrete expected. However I want to do some manual digging to ensure no infrastructure is in the way.
A Bosch question for you, Mike: I am greasing my bits with a dab of Bosch grease on the SDS splines. After a some drilling/hammering, I break to let the drill cool down and I change bits (e.g. drill to spade bit.) When I pull out the bits, their shank has black grease on them. Where is this grease coming from and does this need to be routinely replenished? If so, where and how does one do that?

Thanks, Greg
20221015_101801.jpg
 

Attachments

  • 20221016_092652.jpg
    20221016_092652.jpg
    859.8 KB · Views: 5
Last edited:
I said it, great basic hammer drill. I might own 10 of them.
 
gjmontll said:
Mike in Ore,
Again thanks for your advice. Following it, I too got a used Bosch Bulldog on eBay (for $80.) It came with a bunch of drill and chisel bits and ran okay. But something in the SDS chuck was messed up, the collar would not slip up to lock the bit. This really slowed down my effort on my first hole, but that was just hard clay, no concrete.
Then I ordered an $8 Bosch chuck rebuild kit (everything from the spring to rubber tip.) Problem fixed.
Yesterday I dug the 2nd of 3 holes for my antenna masts, this one a 12x12x28". As expected, a few inches down I encountered the buried drain ditch, you can see its concrete sidewall in my attached photos. Between the clay and the concrete, the whole hole took about 3 hours of drilling, chiseling, and bailing out the pieces.
Today I filled the hole with 200 pounds of Quikrete holding my half-"PostMaster" mounting plate into position.
Tomorrow or Tuesday I hope to do the final hole. No concrete expected. However I want to do some manual digging to ensure no infrastructure is in the way.
A Bosch question for you, Mike: I am greasing my bits with a dab of Bosch grease on the SDS splines. After a some drilling/hammering, I break to let the drill cool down and I change bits (e.g. drill to spade bit.) When I pull out the bits, their shank has black grease on them. Where is this grease coming from and does this need to be routinely replenished? If so, where and how does one do that?

Thanks, Greg
View attachment 423742
Click to expand...

I do not know the ins/outs of the Bosch hammer drills well enough to advise you. On mine the gear box for the hammer action is filled with grease. If I overheat the drill a bit of grease will push out of the gearbox. I have not looked for a plug to remove to refill the gearbox... but, now that you mention it, I REALLY should!

Good job on your project! I am happy to hear that the hammer drill is working out for you!

P.S. There are a lot of Bosch hammer drill rebuild videos on youtube. I was just looking for my particular model.
 
Last edited:
You must log in or register to reply here.
Back
Top