Having spent an afternoon helping someone get a geetech delta slightly closer to working, and that being a very cheap delta at over 5 times the price… No.
Not gonna lie, I’m really tempted to build a 28BYJ-48 based 3d printer now just to prove it can be done and work well. I would NOT build a delta with them though. Deltas need too much motor speed when the arms get close to horizontal. With the gear ratios required for torque, you just can’t expect much shaft speed out of them.
Hmm, so Ryan thinks the Due is obsolete but you can make a decent printer from $1 steppers… something does not compute 
Hey, it’s all about how fast you want to go I target 200mm/s on most of my builds, but I bet I could make a small and slow printer with $1 steppers, yeah. (Probably cheat and use two per axis though.)
@Nathan_Walkner I generally agree with that, but I already have a bunch of high-quality printers. Don’t really care if my oddball just-for-fun builds are reliable. It would just be an exercise in figuring out how much performance can be squeezed out of those steppers.
@Ryan_Carlyle yeah… the Vulacanus (? 14 year old kid from Germany) created the Cherry printer. It’s Cartesian, Printrbot class. It runs at around 10mm/sec. Any higher and the stepper motors will melt.
@ThantiK Tiko hasn’t shipped yet. They have been pretty good at updates, and sound sincere. I’m really curious how it will turn out, but my expectations are very low.
@Francis_Lee That doesn’t make a ton of sense… steppers pull less current as they speed up. He must have been cranking up the drive current to try to go faster. That’s not the right approach, you should increase the PSU voltage to run the steppers faster.
There’s the ToyREP http://reprap.org/wiki/ToyREP That guy says 10-12mm/s with 1/64 gear ratio motors and 12v PSU. Based on napkin-math alone, bet I could get 40mm/s with a 24v PSU, 1/16 gear ratio motors, and low acceleration values. Would have to take some motor spec measurements to calculate rigorously. I have a couple motors on order from Adafruit now, will play around with them when I get a chance.
Those stepper burn out all the time. I wouldn’t be surprised if they are easy to replace but don’t expect them to last long at all…
You can’t even buy the bom for a printer, even at a volume of 1 million units, for $49. Think about it this way, a 2d printer has 2axis a 3d printer has 4 (feeding the plastic takes a stepper) just increasing the count by 2 should at least double the cost. Even for the cheapest printers ( for inkjet~$30) a $50 prices is to low.
This company will fail, they do not have enough margin to sell the product.
Cheapest hot end ~$15, cheapest steppers $2($8 total) cheapest electronics board ~$20. Without a frame or chassis you have $0 profit.
Can’t agree with you there @Camerin_hahn . Those motors at bulk could be below $2 by a long shot and hotends are wicked cheap on places like aliexpress (I’ve seen some at $6 shipped). If they do their homework and machine the heat break well I don’t think they would have a problem manufacturing one for under $5. But that takes time and work.
Agreed. Appears destined to be another flop. Too bad people don’t really think intelligently about logistics. This will also probably end up being a support nightmare. Like Cobblebot.
$49 was the early bird rate. The regular price is $75. Still no margin, but they might be able to buy the BOM if they get enough volume.
@Griffin_Paquette so you have tested the hot end on Ali express? The jhead clones only look like a hot end, they cut machining time by reducing internal features that are critical to function. E3d is selling the light at ~$30 I assumed 50% mark up to get my margin. You could go ubis ~$20. But really the quickest way to a jammed non functional printer is buying a $9 hot end. This is mission critical hardware.
The steppers on the hot end have high torque requirements. You will not get by with the cheap steppers. You need nema 17. But lets assume you get it for $1 each. ($4)… I pay $6 each when I buy quality ones, but let’s assume $1.
Then you have the stepper drivers. Each driver, unpopulated, is $1.68 from ti, if you go with Chinese clones you can get it down lower, but you will suffer in performance, so I am using the ti price and assuming assembly is free we are still at $7 in drivers. The mega is a $10 processor. So without connectors, wires or support components or PCB/PCB assembly we are at $17 in electronics. Let’s assume we can pressure our venders to give is reasonable clones of each of these chips, the PCB, assembly, connectors, and support parts for the cost of the real parts.
So $17 is the electronics $4 is the steppers, $10 is the hot end (that won’t work) so before mechanics we are at $31 dollars.
So you think you can build all of the belts, sliders mounts, cables, packaging, instructions, screws, effector rods, motors mounts, and frame for $18.
Then after you built that you think a company can run on $25? Let’s do that math. Assume you make minimum wage in the US, that is $36k a year, your engineers want much more than that, but let’s assume that is the employees wages for everyone. You need to sell 1500 printers per employee per year. Assuming you have one designer/engineer/sourcing expert/owner and one packaging employee that is 3000 units a year… But we didn’t play for storage yet. We can’t just keep the assembly line running, so you need to have storage. Let’s assume you pay $300 a month climate controlled storage (I don’t know where you get that rate for this size of project, but let’s pretend), oh and $50 for Internet, and $300 for office space. That is 3500 printers a year… But you need to pay taxes… That is about 4500 printers a year. So that is selling 15 a day… Does this model sound viable still?
2 people sell 15 printers per work day to make $36000 a year each. And they don’t have benefits, retirement or unemployment.
Oh all of the above math assumes that there is no debt, investors (who take money from the company without putting in work), or shipping costs. It also assumes that all board, mechanics, and packaging does not have an nre or revisions.
@Camerin_hahn Shipping cost is paid by backers later. Gotta assume the founders work for sweat equity here. (Which is dumb for a crowdfunding campaign, but whatever.) The frame and linear hardware is injection molded crap and two lasercut sheets, plus a few cheap vitamins. They CAN probably get the BOM for <$75 in quantity over 1000. Then we have to assume they’re doing it “at cost” or close to that, in order to try to launch a brand and then get investors / bought-out / acqui-hired.
Probably won’t end well.
@Ryan_Carlyle an injection molded part that size is about $20. That is because the size of the press required fill the cavity is really large. Plus the nre for making the part is ~$200k (I know because at work I have worked with a few parts that size at work). That is in volumes of $2000, and there is a $500 hanging fee each time you want to run parts
@Nathan_Walkner I am assuming that the person running the Kickstarter is in an English speaking country… US, AU, GB, CA, etc.
I am assuming 1 of the workers are from there and expect that sort of wages, as in minimum wage
@Nathan_Walkner also the only thing you call out is “the owners wages could be lower” not that I rounded down everything on the bom below a reasonable cost for each piece