What would convince you to purchase a 3D printer? Low price? Ease of use? A viable purpose? If so, then 3D printing start-ups may be on the right track.

While 3D printing's uptake has been impressive -- a 33.8% compound annual growth rate over the past three years -- the machines have yet to find a place beside the coffee maker on the counter.

"A general-purpose 3D printer will not be sitting on most kitchen counter tops," said Terry Wohlers, president of additive manufacturing research firm Wohlers Associates. "A food printer might in the future, but we don't yet know enough about how the market will respond to their availability."

A little more than a year ago, finding a 3D printer for less than $500 was hard.

Now, companies such a XYZprinting, with its sub-$500 da Vinci machines, are hoping to bust into mass-market adoption. Of course, that hasn't happened... yet.

XYZprinting XYZprinting's da Vinci Jr. 3D printer will begin shipping in May for a retail price of $349.

As 3D printer prices continue to drop and their ease of use increases, uptake of "lower cost" machines has skyrocketed, although the nascent market remains small.

The market for low-cost desktop 3D printing -- machines priced under $5,000 -- was strong last year, according to the Wohlers Report. Sales grew by 82.5% to an estimated 139,584 units in 2014.

But most of those 3D printers are being purchased by companies for design, modeling, and prototyping, or by educational institutions.

"A much smaller percentage is going to 'geek dads,' hobbyists, and some do-it-your-selfers," Wohlers said.

But, if recent crowdsourcing campaigns are any indication, the consumer market is champing at the bit for something affordable and easy to use.

The $179 3D printer

For example, Tiko, a start-up based in Niagara Falls, N.Y., has boiled down the 3D printer to a simplified "unibody" design embellished with cutthroat pricing.

At only $179, the Tiko 3D printer has blown up on Kickstarter, leaving the original $100,000 funding goal in the dust and garnering more than $1.2 million in pledges after only eight days.

Tiko The Tiko 3D printer features a unibody design and no rails, on which printer heads and platforms typically move. Instead, the machine positions the print head at the end of a downward facing tripod. The tripod's arms move in unison to control movement of the print head, but the print platform remains in place.

What makes the Tiko 3D printer unusual is that instead of using multiple rails on which a print head and print platform move while filament is extruded layer upon layer, this machine positions the print head at the end of a downward facing tripod. The tripod's arms move in unison to control movement of the print head, but the print platform remains in place.

When the Tiko is done printing, a flexible print platform disconnects, enabling easy removal of the printed object.

"With this simple shift in design, all the problems that came from separate rail systems disappeared," the company said in its marketing video.

Tiko also uses W-iFi instead of USB cables to connect to laptops and desktops running the CAD software needed for 3D printing. The company also came up with its own cloud-based software that allows users to print from mobile devices.

Another start-up aiming to use the cloud to gather converts is New Matter, a Pasadena company that recently blew past previous 3D printer crowdsourcing campaigns on Indiegogo with a $249 machine. While the printer is indeed slick, surrounded by a transparent cube, its capabilities are average among consumer 3D printers.

Tiko The Tiko 3D printer has an internal plastic filament spool from which it prints.

A sub-$400 printer that uses a social network

New Matter, however, raised close to $700,000 (its goal was $375,000) during its crowdsourcing campaign, and it pre-sold 2,600 of its MOD-t 3D printers for $149 to $249. The company also recently raised $6.5 million in a series A funding round. The company expects to begin fulfilling 3D printer orders this summer.

What sets New Matters MODt 3D printer apart is that is uses Wi-Fi to connect users to an online marketplace where sharing a printable object file is as simple as sending a text message.

"All the processing of the .stl file, from uploading it to print commands to slicing and print generation, will be done on our servers. The printable file then gets streamed to the 3D printer," said New Matter founder Steve Schell.

The .stl file format --.stil is an abbreviation for stereolithography -- is the default standard for computer aided design (CAD) images used by 3D printers to make objects.

When an .stl file is uploaded to a 3D printer's simple CAD software, the object image must first be "sliced" into the dozens, hundreds or even thousands of layers a printer will use to create it. Slicing an image can take several minutes or much longer depending on its complexity and the processing power of the computer on which the software is running.

MOD-t owners sign on to become part is the online community that allows users to upload and download .stl files, and even charge for designs. Typically, popular software such as Tinkercad, Autocad or Adobe's Photoshop CC (creative cloud), or some proprietary software, allows 3D printer users to perform simple manipulations of objects before they print.

New Matter The MODt 3D printer offers WiFi and a cloud community of users who can upload their designs and then message each other with printable files.

Like a social network, users of MOD-t users can upload CAD drawings to the New Market's online marketplace and then send messages to other users with links to .stl files. Users get notifications, and they can chose to accept them and print the objects, ignore them or reject them.

All of the objects uploaded to New Matter's servers, however, are vetted to ensure they work well with the printer; often times objects downloaded from online marketplaces such as MakerBot's Thingaverse don't print well on all machines.

Users of MODt 3D printers will also be able to manipulate objects in the cloud using New Matter's CAD software before printing them.

"Today, the software can perform basic manipulations to an object's geometry, and it can do things like embossing text, so you can print a phone case with a name on it," Schell said.

According to Schell, the final retail price once the MODt goes into mass production in late 2015 will still be below $400.

Even at a reasonable price, though, consumer-grade 3D printers are still a technology looking for a purpose. Printing eye-glass frames, smartphone cases and figurines is fun, but hardly worth dropping a few hundred dollars on.

Wohlers believes that the more likely use for mainstream 3D printers will be to fulfill services.

"Bakeries will operate professional-grade machines and consumers will buy custom cakes, chocolates, etc., from them," Wohlers said. "The same is true for the production of industrial parts and products; consumers will buy them online and at shops and this market will grow very large.

"Most consumers will not be running the machines," he added.