a pantload re: a new patio

I'm laying a 1 1/4" thick travertine patio. (no piece bigger than 8" x2' I've solved nearly all the (known) concerns and issues (thanks to this forum) but these:

Rather than buy an angle grinder I'll use my circular saw and the proper blade (I forgot I once cut 2" bluestone with a (number of) 7" abrasive blades). Can I use a "masonry" rated 7" diamond blade for scoring and or outright cutting the Travertine? Maybe just expect it to wear out a bit faster? (orange box has no 7" diamonds available, blue box seems to only show "masonry" rateds) I know, the world is not only orange and blue but I needed an idea...

I haven't purchased a tamper and I feel like I may be renting one 3 or 4 more times (already once with the first load of base gravel). I read (and have previously heard) that the "pavers" should have a tamper run over them to lock them into each other and the bed layer.
That sounds nice but:
My biggest problem with DIY jobs is that I get the basics right, am forgiven for the simpler (usually cosmetic) faults but I don't seem to ever actually earn an 'A'. My fear here is that after laying the pavers down I'll tamp them and bam -- it'll look like Loma Prieta after the 'quake'. Financially (and I suppose practically) I'd rather not rent the tamper for multiple days while I try to lay and tamp smaller areas. besides that just doesn't seem like it'd work anyway.
Do I _have_ to do it that way? I just remembered:
I've done quite a few feet of brick walks (but never anything so wide like this patio). My strat with the walks was to plop down the brick, rubber mallet tap it down: Level in all dimensions? good move on. Too high? take away some sand. Too Low add a little sand. try again. The last walk I did (10 years ago) gets small city foot traffic and still looks great though there are some low uniform sunken spots (maybe 3sq' total at the soldiers in two different places (ok so B+).

Stick with whatever works for me?

The patio is roughly 12x20 with a curved "dry-look" stone wall along the 20' with two breaks for steps up onto the patio. the other long side has a fire pit about 1/3 the way along.

My added handicap is the wall mason did _not_ make the level of the firepit the height of the steps up as requested. I did catch him and he supposedly addressed it. He used a transit, I used a line-level and string. When he was done the steps were still at least 2" higher. I just wanted a level patio now I gotta f with ablating those two inches somewhere. Its a patio. People (some inebriated more than others, some not at all) will be sitting in chairs around the firepit this Thanksgiving. Should I straight-line descend the slope from steps to firepit (Its a 12' run) (.16"/ft descent). I'd like the area directly in front of the pit perfectly level. I also know there's an amount of UNlevel that people won't feel (tipsy or not) is .33"/ft shallow enough so the first 6 ft from the pit is flat and then the patio slopes up to the step height?

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In the interests of reduce/reuse I'm going to use the remainder of an old-school woven polypro housewrap as the bed course liner. Sound good?


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Is Concrete Sand the same as Concrete dust? Who cares? The mason said use stone dust for the bed. The yard that sold the Travertine said use Concrete (dust). I used "builder's sand" in the brick walks (is there a more proper term for that? It might be the same stuff used by hiway depts. for cutting the road salt during snow storms). Any problems here?

Thanks for listening I hope I wasn't too long winded and you can help.

Line levels aren't always accurate, but transits and field levels (which is what the mason probably had) can be off too. In fact no spirit level should be trusted until checked which fortunately us easy to do. Place the level on a wall and mark where both ends are when it reads correct. For a line level use a coupe nails to holf it off the wall. Now turn the level end for end horizontally, do not rotate it, and align one end with an original mark. (With a line level simply reverse it on the string in the same spot.) Now set the level correctly from that and mark the other end. (With a line level, pull one nail and reset it where it reads correctly now.)The distance between those two marks is twice the inaccuracy of the level. Plumbness can be checked similarly or can be checked against a weighted string line or plumb bob. I like "Stabila" brand levels but even as good as they are they too can be in error.

For a field level or transit the process is slightly different, but with those it's usually better to have it factory calibrated where they'll check, clean, lubricate, and adjust everything then issue a certification document. What most people call a "transit" is actually a "Field level". A Transit is movable uphill and downhill, and has a degree scale to measure the gradient angle in degrees while a Field Level only rotates and can't be moved up and down to directly read a gradient angle. These should always be stored in their case and treated as the precision instruments they are.

When I need best accuracy I use a water level which is simply clear plastic tubing filled with water devoid of any air. When stretched across a distance the water at both ends will be at the exact same elevation and provides a reference point you can measure to. It never needs calibration and can never read in error. A bit of food coloring makes it easier to read.

Phil