Sweet, the dual head one was the one I was leaning towards. What's a ballpark cost on the grinding segments? I'm assuming the rental place would have some available, but if not where could I find some?
I dont use that machine, so I'm not up to date on their tooling prices, but you can expect to pay $25-35 per segment. You should need 6 in total, 3 per disk. I would hope the rental place has them, it would be smart business for them - you never know though! You could probably order online. I'm not sure where their tooling is available. I buy from a place called "World Diamond Source" down in FL for my Husquvarna machine, not sure if they deal with the public though...
The tricky thing though is getting the right bond (whats holding the actual diamond bits in essentially) for the type of concrete. If you have soft concrete, and soft bond metal, the machine will just bog down, and you'll constantly be leaning on it to relieve pressure on the heads. If you get hard concrete, and hard bond, they wont cut in at all, and just slide along the surface, and you'll want to stack a ton of weight onto it.
There should be three bonds available ( Hard, soft, med.) Then also different grits. I'm a fan of being aggressive, so I would stick to 25 & 50 Grit ( Or close to those numbers, I'm not sure that Edco makes)
I wouldn't trust the guys at the rental shop 100% Do you research, and confirm it with what they say... Last thing you want is them selling you 100 grit tooling, and its not working properly.
You can look at concrete hardness maps and get a rough idea what kind of aggregate you have in your area. Or you can test it with a special pick set - they cost $100 so its probably best to look at a map...
S.