I have a friend who wants me to help install a pool cover for her inground pool. I have a hammer drill, but the capacity says 5/8". We would need to drill a 3/4" hold for the mounting holes. I am not sure if my hammer drill is powerful enough to go from 1/8" to 3/4" from what I have read. But would it be fine if I went up to 3/8" and then do the 3/4" bit? I used 3/8" in my fireplace just fine, but 3/4" is a big jump.

Buy the bits to go up in 1/8 increments. The drill will likely handle the larger bits - just keep cleaning out the holes - its the dust in the bottom of the holes that will cause the bits to bind.

A better alternative would be to rent the appropriate tool from Home Depot or Lowes.

I'd rather admit I don't own the right tool than ruin the wrong one - I doubt they'd offer to replace it !!

If the SDS shank on the 3/4" bit fits your drill, it'll work. It may be slower than you are used to but it will work. The trick of double drilling a hole in concrete has never worked for me. Drill the size you want, first pass.

How deep and how many holes?

With 3/4” holes and probably 12 or more if fare size pool I would invest in a rotohammer and not chance burning up your hammer drill. A cheap rotohammer from Harbor Freight or Amazon and can be had for around $100. Many also come with bits, though not very good quality but should last through a couple dozen holes if you don’t hit rebar…..Using proper tool for job will go much quicker. My HF rotohammers are 15yrs old and still working, using on a couple jobs a yr. Don’t have to worry about people stealing them also as when I had Hilti…

My 30+ year old hand held Milwaukee 1/2" drill has a hammer drill option. I have drilled hundreds of holes with it over the years from 3/8" to 3/4" inch. Step up to the larger sizes as mentioned. It is not as quick to do as using an actually rotary hammer drill, but it gets the job done.

Nobody mentioned it but, go all the way through the concrete. Drainage and getting the bolts out later are the concerns.

I did 2 holes on a far end of the concrete to test it out. I took pics and will see if they upload. The numbers and notes are hard to see, but I did one with 1/8" up to 3/4" with 1/8" increments for bits. Then one I did 1/8" right to 3/4". I have a craftsman 7 amp hammer drill. I will look at the Harbor Freight one as well just in case. I will have to wait for the cover and see if the anchors have a lip or what. It did mention 1 5/8" deep holes I think. I am not sure how many anchors it has. I will not mention which one I think looks better because I am not positive how exactly round or deep they need to be. I was going to see if one would slide into the hole and how snug it is when the anchors get here. Not going to force them in because they won't be staying in the 2 test holes I drilled.

Which one would you go with if I had to get a bigger one? I plan on using the one I have and if it burns up, I will run to Harbor Freight to get a new one. Have a HF like 5 minutes from the house. Rather not spend the money if I don't have to. Not worried if it takes longer with a smaller drill.

https://www.harborfreight.com/power...-variable-speed-rotary-hammer-63443.html

https://www.harborfreight.com/build...-variable-speed-rotary-hammer-58214.html

This is what I have and just use 3/4” bit or what’s called out. Nice thing about tool like this is it can be used for chipping concrete lightly or busting tile up. It doesn’t hurt to get a tube of epoxy to bed the anchors in also.

https://www.harborfreight.com/10-amp-1-18-in-sds-type-variable-speed-rotary-hammer-64288.html

I just picked up the last one at the local HF. What grease do you use when the supplied can runs out? Also, what are the two small electrical pieces in the bag with the manual and the rubber boot in the case?

1) Grease
2) Guessing they are replacement brushes.

Depending on what anchors you use i would go at least 3 inches down. Typical wedge anchors need some room to catch and expand. If the hole is slightly larger it may not catch or need more space. Also the closer to the surface you run the risk of cracking/chipping off the surface when you tighten it. I have installed plenty of these.

The pool cover comes with anchors and says to drill down 1 5/8". I have drilled into brick to mount a tv, but that was only 5/8" holes. My old drill was fine for that. The anchors for the pool cover call for 3/4" hole and didn't want to burn up the drill I have so I got a new one.

Got the pool cover installed. Thanks for all the advice. Was 30 anchors and went smooth with a small hammer drill to do the pilot holes and then the HF one for the final one. Most went in straight, some went in on a bit of an angle, but all in all, we are happy.