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I'm packing medium-sized gravel (1.5"-minus crushed rock) in to holes, to provide a stable base for pier blocks in clay-rich soil. There are 30 holes, roughly 24" diameter, 18" deep.

I have a 10" x 10" hand tamper, but my carpenter friend said that would only work well on smaller rock. He suggested using a 4" x 4".

I have been tamping & tamping, and now my joints hurt, and I have a lot more tamping to do. Maybe my technique could be improved? Maybe I don't need to tamp as thoroughly as I have been.

I tried googling for tamping info, and mostly I came up with tips for making espresso. And every site that mentions tamping gravel just says "step 5: tamp gravel" and gives no further details.

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  • How big of an area are you doing? Or, really how many blocks are you putting down? This would help in determining the best tool for the job. May 6, 2011 at 17:13
  • @TattonChantry: Added some notes on that.
    – Jay Bazuzi
    May 6, 2011 at 18:10
  • Step 5: Hire cheap laborers to tamp gravel.
    – Tester101
    May 6, 2011 at 20:12
  • I ended up renting a gas-powered tamper. Sure enough, it's very heavy so most of the work was moving it from hole to hole. I'll keep the question open to see if any more good info comes in, though.
    – Jay Bazuzi
    May 7, 2011 at 1:30
  • Grab a motor from an old airconditioner fan. (1720rpm IIRC) Put a 10 pound weight over the motor shaft, then jam something onto the shaft to keep the weight from coming off. 1/2" shaft 1-1.5" weight hole, so it's going to wobble violently. Bolt the motor to a cafeteria tray, and put on a 4 foot handle for dragging the thing around. Wire up the motor, with a switch on the handle, and go at it. For a round hole, a pizza pan, or frying pan might be better. Used this to to tamp my sand, gravel and brick patio. It's been stable for 13 years. -Much cheaper than renting a tamper. May 10, 2018 at 21:08

2 Answers 2

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Manual tamping is hard labor. Consider it gym time. You'll want to add a few inches, maybe wetten it slightly, and start pounding. Repeat until you get to the top.

Alternatively, rent a power tamper and save yourself a lot of time and aches and pains.

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    Power tampers are good for large areas (i.e. driveways,patios,sidewalks), but not as good for holes. You'll end up breaking your back lugging it from hole to hole, 30 holes is a lot of holes.
    – Tester101
    May 6, 2011 at 20:07
  • They make handheld ones for that such as these: crowderpneumatics.com/store/…
    – DA01
    May 7, 2011 at 0:40
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Jay, you may be working way too hard. Your question said you have only 1.5 inches of gravel over crushed stone etc. right? Your carpenter friend is probably right, a 4X4 should work fine. Don't get too carried away, as long as the fill is reasonably firm, you should be OK. You don't need to pack it as hard as concrete. If you fashion a comforable "T" handle onto the top of a 4X4 it will make the job a bit easier. What are you using for the bases? Concrete blocks or concrete porch posts? If you are using porch posts, I got some great tips for ya, let me know. Do you have a small bobcat or similar with a front end bucket available?

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  • The gravel fit through a 1.5" screen, but there is 12" - 24" of it in each hole. The blocks are pre-cast concrete with a bracket epoxied in, like goo.gl/zvx9k. To make leveling easier, and to leave a crawlspace, we'll put 4x4 posts on that. I can rent a small loader, like a Dingo pretty easily.
    – Jay Bazuzi
    May 7, 2011 at 17:48
  • Well Jay, it would have been easier if you had tamped the gravel every 6" or so as you went along. Also curious why with a nice deep hole like you had, you didn't use sauna tubes or porch posts? Regardless, you can water soak the gravel to help it settle. Hand tamping 24" of gravel is tough, if not impracticable. I thought if you had a loader, you can hang a porch post from the bucket and use it as a tamp. Let the machine do all the work. May 8, 2011 at 10:04
  • I really ended up in somewhere I didn't plan on going. The holes were supposed to be 12" deep (our frost depth) and 18" square, but I got a little crazy with the digging machines.
    – Jay Bazuzi
    May 11, 2011 at 20:12

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