Tools, Sharpening and Power Machinery - cutting concrete

I am removing a section of my concrete floor, so I can expose and move some plumbing.
I have drilled beat and hammered and I have a hole that is about 5” in diameter to show for it.
I was going to rent a concrete saw this weekend, but the rental place says they only put abrasive blades on the portable saws because people don’t know what they are doing and break the blades.
I am sure an abrasive blade will eventually get through the concrete…but there has to be a better way.
Are the dry masonry blades you can buy for a skill saw any good?
Will the last long enough to cut 20 feet of 4” thick concrete? (20 feet long cut…5X5 box)

just a thought but have you gotten a quote from a pro ?

sometimes its not that much more and well worth the extra few dollars.

Yea, I checked into it, the cost wasnt too bad, affordable even, but I am a do it yourselfer. I have done everything to this house myself, pulled permits, been inspected, there is a sense of satisfaction that goes along with doing it yourself.
That being said, if I cant find a solution to cutting the concrete.....there will be a pro here doing it.

Dude,

if you've got the hole started, that's the hardest part. Here's what I'd do:

First off, go to a different rental store!!! Get a diamond blade and a gas powered (or electric) saw and some ear protection. A filtered gas mask wouldnt hurt either. You probably don't have to cut through the cement 100%. Once you make your 2 cuts, a sledge should easily break through, even if you've only cut a couple inches deep. You might want to think about going a little wider than 5" if your pipe will have any bends in it. It will save you some headaches when you lay the pipe.

If you try to use the abrasive blades for your skilsaw, you better buy a case of them. You'll burn up a lot of blades, get tired of cutting, have a saw cut that's about 1" deep and give up.

The only other thing that might help is a rotary hammer. a lot of times I'll use an abrasive blade to make a cut line (where the cement should break) then use a rotary hammer and 6 x 3/8 SDS bit and drill a million holes along the line- it weakens the cement enough that it will break out pretty easily. But it leaves a pretty ragged edge. The diamond blade is your best bet. (most rental places will measure the blade before they give it to you, then when you bring it back, they measure it again and charge you accordingly.) So you're renting the saw AND paying for wear and tear on the blade. And as the last rental place said, you don't want to break one- they're expensive to replace. You don't force the saw and you only cut straight lines with it.

20 ft with an abravise blade? 4 full inches? hmmmm.

I would find another method. One man alone would need lots of breathing dust protection and frequent relief from fatigue. More than one blade. Maybe 3 or several more.

You could score the concrete then jackhammer it out. Bottom line, there is no easy way to do it. Lot's of sweat.

I agree with XSleepers suggestions completely.

I like doing it myself ro , but for hard. nasty, potentially dangerous work I dont mind paying someone else .

I like doing it myself ro , but for hard. nasty, potentially dangerous work I dont mind paying someone else .
:thumbup: if i'm not bleeding i'm not working :D

Well I finnaly found a place that would put a diamond blade on their concrete saw ($25.00 extra charge)
I made mince meat of that concrete I tell ya!
I had the floor opened up in about 30 min, replaced the plumbing...backfilled...vapor barriored...mixed and poured 4 80Lbs. bags of concrete. Troweled it smooth as a babies bottom.

Thanks for all the input guys

Just had to cut into the deck on my pool. Rented a gas saw. Had an abrasives concrete wheel 12"X1/8 new on it cost for wheel $8.00 cut8'X4" about and hour water hose on it. Didnt eventake a 1/8" off the wheel

ED ;)

Well I finnaly found a place that would put a diamond blade on their concrete saw ($25.00 extra charge)
I made mince meat of that concrete I tell ya!
I had the floor opened up in about 30 min, replaced the plumbing...backfilled...vapor barriored...mixed and poured 4 80Lbs. bags of concrete. Troweled it smooth as a babies bottom.

Thanks for all the input guys
:thumbup: love it when a plan come's together