As 3D printing becomes more affordable and adaptable, it's making everything from machine parts to guns to food for both astronauts and the elderly. Like all great technology, we've figured out a way to make it work for sex, too.

You can find free 3D printing blueprints for dildos and plugs, saving you some of the hassle and potential embarrassment of picking one up IRL. But these toys aren't ready for use right off of the printer, and can cause internal damage while spreading germs in the process.

When a 3D printer begins making an object, it does so layer by layer. Over time, the layers build up to make the proper form of whatever it is you're printing. But 3D-printed sex toys are particularly dangerous for two reasons: The surface is too rough for immediate use, and microscopic gaps in the toy that are almost impossible to disinfect can store bodily fluid and bacteria.

Even if you sand down the surface of a 3D-printed toy, it's not totally safe. "It makes it look smooth, but it doesn't make it microscopically smooth. It doesn't seal the holes or gaps, so I don't think that's really the right answer," Tom Nardone, founder of MakerLove.com, which provides free designs for 3D-printed sex toys, tells Mashable.

A sex toy that hasn't been cleaned properly can cause bacterial vaginosis (also known as "thrush"), cystitis (inflammation of the bladder) and sexually transmitted infections, such as chlamydia, syphilis and herpes.

Toys typically come off the printer with lots of rough, excess material, adds Nardone. And even when that's all stripped away, the surface is still too coarse for use.

"You wouldn't make a flip-flop from a 3D printer because it would wear away at the bottom of your foot," he says. "You wouldn't make a mouth guard out of a 3D printer because it would cut your gums. You wouldn't make a sex toy out of it because it would damage you internally."

But there are ways of making 3D-printed sex toys (more) safe for use. Acrylonitrile butadiene styrene (ABS) plastic is a popular substance for 3D printing. Nardone says it's chemically safe for one's body. If you print out a toy with ABS, you can smooth it and seal it to make is usable.

The smoothing can be done with a sander or chemical bath, and Nardone says you can seal the toy by applying several coats of silicone conformal coating, which is used to waterproof circuit boards. You can get a can for about $15 or $20, but be prepared to spend some time spraying, since each layer is very thin.

If you don't feel like applying a permanent seal, you can also put a condom over the toy and throw it out when you're done.

While there are laborious ways of making these toys safe for use now, Nardone says 3D printing technology is still years away from immediate safety post-print.

"I think a lot of people right now who are using the website are just sort of seeing what they can print out," he says. "We're a long ways away from the Star Trek replicator."