I mixed 92 pounds of mix by hand with shovel and trowel in a big plastic tub. Total added water was 4.5 quarts.
Hand mixing is slow. I didn't time it, but let's say it took 30 minutes total to mix and then weight out two buckets of 45 pounds of wet concrete each.
Then I poured it into two 16 inch diameter circle molds. (I'm making DIY weight lifting plates.) I tamped down the mix to level it with a wood block and tapped the mold sides.
There was a small amount of water bleed on top and bottom edge of molds which were not attached to a plastic sheet underneath. I sponged off the bleed water with a paper towel just one time a few minutes after leveling the mix in the mold. Then I covered it with a plastic sheet.
The concrete to water ratio seemed good. I didn't go over the recommended max, not much bleed, the mix leveled off with a smooth top. Actually, I improvised a 12 inch slump cone while mixing, and that seemed good. It held up with only an inch or two of slump.
I figure I spent about one hour, no more that 90 minutes, starting the mixing to finally leaving the mix in the molds to set. Would that amount of time be considered overworking? At what point in time toward setting will mixing the concrete again ruin its strength.
Part of the reason for my concern is I used left over mix to make a 1.5 x 7 inch disk using a metal can with the top and bottom cut out. The day after all these molds set I removed the 7 inch mold first as a test. The concrete stuck to the metal mold, which I had oiled, so I tried tapping it out with a mallet. I got it out without breaking, but later while holding it in my hand, it just broken in half from its own weight. It had been setting for 12 hours.
I removed the 16 inch molds with no trouble at all, but waited a full 24 hours of setting time before pulling the molds. Both 16 inch plates are now pond curing in a tub of water.
I'm not sure if I did a bad mixing job or just treated my 7 inch mold too roughly while it was still soft and uncured.