sandbags as "clamps"

Sandbags can be used as clamps. [2] In fact, when gluing a large panel, your only two options are likely weights and cauls. Sandbags can also be used as ad-hoc supports for oddly-shaped parts.

There are three main types of sandbags available — intended for flood control, intended for photography/videography, and intended for making canopies more secure. I like the canopy style the most, as long as they have only one compartment, because that allows the sand to be moved around somewhat, making the sandbag more flexible.

Some tips and tricks:

• bag material
  • Sandbags designed for flood control are fairly low-quality as they're likely designed for a single use, and they will almost always leak. Some videography and canopy sandbags can leak too, or at least burst a seam. So I prefer to nest them — one flood-control sandbag inside a canvas sandbag.
  • Canvas sandbags are rated in deniers, the higher the better.
• fill material
  • Your local home center probably has a variety of sands and gravels. I've found their cost-per-weight ratio to be roughly the same, so pick whatever suits you the most.
  • Honestly, I like cat litter, since that serves a dual-purpose in case I ever run out of cat litter. Just avoid getting it wet.
  • If you're going for an especially heavy bag, I haven't found anything local that's better than any other, they seem about equivalent. There are steel shot sandbags available online, though they're kind of pricey.
• places to buy them
  • They're almost exclusively available unfilled, since shipping sand long distances isn't economically viable. Buy your bags online, and buy your filler material locally.
  • Amazon is a good place for most sandbags, of course.
  • If you want high-end sandbags, there are specialty places like SandbagStore.com.
  • Sandbags are used for weight training, so you may be able to find some at a local sports store.