Yesterday was a miserable day to be invested in the 3-D printing industry. In one fell swoop, analysts at Piper Jaffray took down shares of both 3D Systems (NYSE:DDD) stock, and archrival Stratasys (NASDAQ:SSYS), warning that the entire industry appears to be falling apart. Or almost the entire industry.

The news

According to Piper, 3D printer "demand was significantly below plan for both 3D Systems and Stratasys in the June quarter." In fact, as reported on StreetInsider.com, Piper calls its second-quarter 2016 survey results "the poorest we have seen in recent memory."

Accordingly, the analyst warns that "Q2 and 2H results" for both 3D Systems and Stratasys "will come in below consensus expectations." The banker recommends that investors sell 3D Systems, and at the very least not buy Stratasys, rating the former underweight and the latter neutral.

Here are three things you need to know about the news.

Watching
"I wonder if there's still a way to make money off this 3D printing thing?" Image source: Getty Images.

1. 3D stocks are down, but there's still hope

Piper's downgrades sent 3D Systems stock down 8% in Monday trading, and cost Stratasys stock 9% of its market cap. At the same time, though, Piper made one interesting observation that may suggest a 3D printing stock that you can actually buy.

According to the analyst, you see, one big reason both of these stocks are flailing, is the launch of a new "Fusion Jet" 3D printer from HP Inc. (NYSE:HPQ). According to Piper, "several customers have and will likely continue to pause purchasing to assess" new 3D printers coming on market. At the same time, "several existing DDD and SSYS resellers are likely to partner with HP, which will likely distract channels and stress relationships."

And that sets an investor like me to wondering: Could HP actually be the right 3D printing stock to buy?

2. Maybe

Consider: 3D Systems stock is not currently profitable. Neither is Stratasys stock. Both companies sport negative P/E ratios and are burning cash like it's going out of style. Last year, S&P Global Market Intelligence reported $25.5 million in negative free cash flow at 3D Systems (and $655.5 million in GAAP losses) versus more than $106 million in negative FCF (and nearly $1.4 billion in losses) at Stratasys.

HP, in contrast, is just humming along. 2015 results show positive free cash flow of $2.9 billion, and positive earnings of $4.6 billion.

3. But what about the future?

At last report, HP stock was selling for a P/E ratio of just 7.3. Of course, analysts quoted on S&P Global don't foresee much growth coming out of HP's PC-intensive business. Long-range forecasts average just 1% annual growth for the PCs-and-printers giant.

But HP's monster 5.1% dividend yield goes a long way toward making up the difference between the growth rate, and the P/E, giving the stock a total return ratio of only 1.2, which almost seems cheap enough to buy.

And one final thing: Statistics can be misleading

Granted, growth investors may still find 3D Systems and Stratasys stock more enticing based on their above-average projected growth rates. Analysts who follow these stocks (at least, analysts other than Piper) continue to expect to see earnings growth of 10% annualized at 3D Systems, and 43% growth at Stratasys.

But before taking these estimates at face value, investors might be well advised to ask themselves: Growth of what profits? HP is profitable, and even if it's only growing at 1%, then at least you can trust it will be slightly more profitable next year than this year. But earnings "growth" for the last quarter at both 3D Systems stock and Stratasys was listed as "N/A" on Yahoo! Finance, while revenue "growth" was negative. And I've never quite understood how a company is expected to grow negative profits 10% -- or 43% -- or whether growing negative numbers is really a good idea.

If you ask me, HP may not be the most exciting way to play the 3D printing trend. But it just might be the safest.

Fool contributor Rich Smith does not own shares of, nor is he short, any company named above. You can find him on Motley Fool CAPS, publicly pontificating under the handle TMFDitty, where he currently ranks No. 284 out of more than 75,000 rated members.

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