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Warning, a lot of stupid random thoughts ahead.

So, I don't want to buy a vacuum pump to vac-bag my parts. I only make a wing or two a year. And my house is small so I don't have anywhere to keep all this stuff.

I have been using a hand pump, a car brake-bleed vacuum pump. It's a pain to use, but it works.

Other ideas:

1: wet up part with carbon and epoxy, then wrap peel ply and paper towels. Place this into a waterproof bag, then sink into a deep bucket of warm water - say, 1m deep.

2: wet up part with carbon and epoxy, then wrap peel ply and paper towels. Place this into a plastic bag, put in pit, fill pit with sand.

For home made parts, I'd assume that either method would be OK and give reasonable results.

Soft foam with boards or ply on outside, then clamp or weight (sandbags, rocks, bricks...) ,works great for me.

You have a fridge in your house?

So there you go. Your fridge compressor does not take a lot od space. The fridge does.

I found this technique extremely useful, the "poor man's vacuum" series, as in https://vimeo.com/188255088.
I have been using it for laminating boards and also for some smaller custom parts. I am not sure though how well it would work for wings.

I like the sand box idea. You could make it with a top plate that you can clamp extra pressure and get good distribution of load. That said. That would take more room than a fridge pump.

Just use a vacuum cleaner and clothing vacuum bags you can get on Amazon. Can get pretty good results if there are not complex shapes

Buddy made a working wing vacuum pump from an old junk freezer. Free!

Clothing Vacuum bag works great for laying down a top layer or layers, on wings forms, whether wood or foam, but you need some bulk junk towels in there to to get a proper vacuum, just put them off to the side in the bag.

kjorn wrote: 1: wet up part with carbon and epoxy, then wrap peel ply and paper towels. Place this into a waterproof bag, then sink into a deep bucket of warm water - say, 1m deep.

2: wet up part with carbon and epoxy, then wrap peel ply and paper towels. Place this into a plastic bag, put in pit, fill pit with sand.

1: 1m sink in water equals 10% of vacuum (atmospheric pressure). It is not enough, you'd several meters deep pool to have enough pressure.

2: atmospheric pressure equals 10m of hydrostatic (water) pressure. Sand weighs not even twice as much as water, so you'd need several meters of sand piled on your part to have comparable results.

It should be remembered full vacuum produces not at all very high pressure, for example board industry uses hydraulic presses with several times more force. But for most uses vacuum works well.

There is no reason to try reinvent wheel. Get somewhere working vacuum pump and use it. Fridge compressor works very well, it can pull at least 90% vacuum with no problem.

Sand box could be useful for small parts if after burying object there some plate is put on top of it and then additional pressure is applied somehow (clamps, car jack).

You can often make ok quality without vacuum.
Wet-out every layer on a separate piece of plastic, and use a bristle roller to consolidate on the part.