Glowforge is delaying shipments of its 3D laser printer again, and customers aren’t happy.

The Seattle startup informed backers this week that it will delay shipments until 2017. The original plan was to ship its printers to thousands of backers in December 2015, but Glowforge has delayed shipments three times now. It did so initially in February and again in April, at the time promising a revised ship date of December 2016.

Glowforge CEO Dan Shapiro wrote a lengthy email to backers on Thursday, which he also posted in the Glowforge community thread, recounting a morning in November when he arrived at the office to find that the number of Glowforge printers awaiting troubleshooting was larger than those that were working.

“After talking to everyone, I sat down with our team,” he wrote. “After hours of consideration, we came to a painful conclusion. We are not ready to start producing in quantity yet. The only way to build your Glowforge with the quality and care it deserves is by spending more time on testing. This means adding more time to our production schedule.”

Glowforge set a crowdfunding record last year by raising nearly $28 million from backers who pre-ordered in October 2015. Its printer uses a laser to quickly cut and engrave products and lets people use raw materials like leather, paper, plastic, fabric, or cardboard and make items with a push of a button.

“We let you down and we’re not going to make our schedule,” Shapiro wrote. “Depending on your order date, your Glowforge will arrive between March and August. You deserve better. We are heartbroken to disappoint you.”

You deserve better. We are heartbroken to disappoint you.

Shapiro laid out the new timeline: “We will be manufacturing hundreds of units per month through February and scale up to thousands starting in April. Most customers will get their deliveries in May through August. All orders placed before Oct 26, 2015 will be shipped by July 31, and all subsequent orders by August 31.”

Many backers weren’t shy about expressing their frustration on the community forum. User “scottmillersb” said that he backed the company within a few days after its public unveiling. But now he said he “can’t help but feel a sense of betrayal by this latest announcement.” He wrote, “At this point my question is why should I trust you and your company? You have blatantly deceived us about the shipping date originally and perhaps in subsequent updates?”

Other backers expressed similar disappointment and sharp criticism of Glowforge, and some said they planned to cancel their orders. One backer wrote, “Even if you were to refund everyone their money by now you would have make a nice chunk of change just on the interest.”

Shapiro responded and said Glowforge has “made $22 per person in interest” and is spending that money on “the materials we’re sending you because of the delay.”

A few backers want more behind-the-scenes updates from Glowforge. Here’s a post from user “stilts”:

i think this is what ALOT OF US would like to see MORE transparency in the Glowforge company we want to see pictures of the [factory] floor we want to see videos of things that you are doing we want to see things being done we what to see out money being in a good place and good standing we what to see details of your everyday we want to see what exactly we are supposedly getting

While most backers let their frustration be known, some were more understanding.

“Dan, i am disappointed,” ‘js1’ wrote. “But i would be more disappointed if you would send me a bad product. So please deliver 100 percent and the best product you can. I would even wait another 12 months if [necessary]. So don’t feel pressured to deliver something what is not 100 percent. Quality is function number one.”

Those who want to cancel their orders for a refund can do so here.

In September, Glowforge announced that it reached $45 million in sales. The printer retails at $2,995 for the basic model and runs up to $5,995 for a premium version. Those prices were discounted heavily during the crowdfunding campaign.

This past August, Glowforge raised a $22 million funding round from Foundry Group and True Ventures, pushing total funding to $31 million. The 42-person company was founded in 2014 by Shapiro, who created the popular kids board game Robot Turtles — one of Kickstarter’s most successful campaigns ever — and fellow Seattle area startup veterans Tony Wright and Mark Gosselin.

In the email to backers, Shapiro noted that the delays are “going to cost a lot of money.”

“Every month that you wait, we spend more than a million dollars to make your Glowforge better,” he wrote. “A normal company wouldn’t do this; they would have to rush their product out the door because delays are so profoundly expensive.”

In response to a question about the company going bankrupt, Shapiro said “we’re fortunate to have one of the best hardware investors in the business,” likely referring to Foundry Group Managing Director Brad Feld.

“I shared these details with him this week, and he’s fully supportive,” Shapiro wrote. “We have more than enough money in the bank to operate without spending a penny of the funds you’ve paid us, which are reserved until we ship your Glowforge.”

Shapiro also wrote about previously “secret” features of the printer, like an expansion port and 50-point sensor monitoring. Due to the additional delays, Glowforge is giving backers more gift certificates while also extending its warranty plans by six months.

Last week, Glowforge announced that it was starting to ship some “pre-release” versions of its 3D laser printer and revealed its U.S.-based manufacturer Flex. The 42-person company said it would provide a shipping schedule update this week.

You can read more backer feedback here. Shapiro said he’ll host a live-stream Q&A on Friday at 4 p.m. PT here.