Update #31: Delay Details #2
Project Update #31: Delay Details #2
Posted by Rinnovated Design ♥ Like |
Hey Backers,
After reading the comments on the last update it was apparent that many of you would like more information regarding the recently announced 4 month delay. We’re more than happy to give you an in depth look at where we stand and where we’re coming from...
We’ve found that delays come in a few different forms, so we’re going to break them down into 3 categories.
1. Expected Work
These are things we knew had to be done, or chose to take on in order to make a better product. In this case we simply underestimated the time it would take to accomplish these tasks, and that results in a delay. Below is a list containing a few of the more prominent ones:
Developing the best mirror arrangement
We explored many completely different mirror arrangements, and even got a bunch of them to print successfully. Who knew there was so many ways to make a 100 dollar printer! Finding the best way meant exploring a lot of roads that eventually lead to dead ends.
Creating and Testing Build Instructions
We greatly underestimated the amount of work involved in creating comprehensive build instructions for The Peachy Printer. Due to changes in the printer design, we also had to do this process multiple times.
The Development of Snapfit
We came up with Snapfit shortly after creating the first set of build instructions. We decided to hold off on shipping the first beta kits so that we could take the time to fully implement Snapfit. Due to all of the new features we added to the printer since PP18, the assembly time had grown dramatically. With the addition of Snapfit, we were able to reduce the build time by approximately 6 hours! Although implementing Snapfit resulted in a 3 week delay in beta shipping, at the very least it will save about 3 years (6 hours*5000 backers /24 hours per day /365 days per year = 3.42 years) of backer time that would have been spent holding and glueing parts. That doesn’t factor in all the time and resources wasted if a part was glued incorrectly.
Developing a Damping System
We knew from very early on that vibrations during a print would cause large defects or even failures. This meant that a good dampening system was essential for the Peachy Printer to produce quality prints on a consistent basis. We’ve since explored and tested many different approaches to this issue. While we’ve come up with a system that dampens vibrations well, it still causes memory. We are still working to develop a better damping system with less memory.
Developing User Friendly Software
In order for the Peachy Printer to be as easy to use as it is affordable, great software is necessary. Packaging for multiple OS’s, making and improving a GUI, adding tools and functionality, and simplifying the printing process are some of the things that we didn’t accurately estimate time for.
Enhancing the Drip System Design
While the drip system was one of the doors to a lower priced printer, there were many improvements to be made in order to make our drip system a reliable one. Things like clogging valves, inconstant drip rates and sizes, air bubbles, salinity levels and many other factors had to be dealt with.
Creating a Flexible and Effective Calibration Process
No two Peachy kits will be built exactly alike. It’s also a very hack-friendly printer. Coming up with a calibration process that’s as flexible as the Peachy Printer was no small challenge. Whether you’ve got a huge or tiny build volume, or decide to use different lasers, apertures, or mirrors, the calibration process remains the same!
2. Unexpected Work
These are issues we did not foresee. They were necessary to deal with and resulted in a more functional printer, however they also lead to a setback in our timeline. Below is a quick list containing a few of the most notable ones:
- Finding that most types of thread cause memory, making it hard to predictably position the laser.
- Finding that oil damping also causes memory.
- Finding that we had to redesign the entire printer with orthogonal mirrors in order to avoid a lot of warping.
- Finding that many sound cards are AC coupled requiring us to design a circuit that demodulates an AM signal and write modulation software.
- Finding that many sound cards have different frequency responses that affect their ability to do amplitude modulation.
- Finding that using power from USB ports often affects the sound signal coming from the sound card.
- Finding that we need to calibrate for how drip size changes with drip speed.
- Finding that normal valves are extremely sensitive to clogging when set to very slow drip speeds.
- Finding very odd behaviours caused by the power regulator that comes with each laser and deciding we must engineer our own specialty laser current limiting circuitry.
- Finding that acrylic plastic was no longer suitable for use after implementing snap fit due to it’s hard and brittle characteristics.
- Finding out that the optimum wire size for coils is simply far too small to handle and breaks often.
- Finding that making coils with very fine wire required us to make our own coil winding machine.
- Finding that a diode on the circuit had a lot more impedance than we originally thought, causing the circuit to not work well.
- Finding a way to simplify the process of tuning the circuit from one that involves 7 tuning knobs to one that only uses 2.
- Finding an inexpensive way for the user to know their circuit is tuned.
- Finding a way to turn the laser on and off with just an AM signal.
- Finding that there is often a difference in ground voltage between the sound card and USB power.
- Finding that turning the laser on and off causes a positional offset in each mirror, and implementing various things to reducing that offset.
- Exploring FM and discovering that it has ill effects and expenses.
3. External Issues
Below is a list of issues caused by external factors that resulted in a delay at Peachy:
- Due to communication issues we were unable to source a coil manufacturer in time for our beta shipment. As a result we decided to produce enough coils for the beta kits on our own winding machine.
- Our shipment of beta circuits took 40 days longer than expected to arrive.
- Our laser cutter took 50 days longer than expected to arrive.
All of the issues listed above have attributed to the current 4 month delay. Thanks to the amazing amount of support we received during the campaign, we have the resources to solve all of these issues. Unfortunately in doing so we’ve taken more time than originally estimated, however as a result you will see a much better product than we would’ve been able to provide had we only reached our original fundraising goal of $50,000. Now let’s take a look at what still needs to be done...
Moving forwards
Below is a list of areas that need further testing and issues that we are still working to solve in order to reach first viable product:
- Memory caused by the dampening system (we’re working on a new magnetic damping system that may have very little memory)
- Resin Shrinkage
- Software usability
- Large prints
- Adding calibration processes for things like laser spot size at wide deletions, refraction, reflection, various non linearities, and offsets.
We hope that we’ve been able to provide you with a better understanding of where we currently stand, and why we are taking more time to further develop the Peachy Printer. If you'd like to read more about these issues, many of them have been discussed at3Dprintboard. Thank you for your support.
Until next time,
The Peachy Printer Team.
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Universal interfaces are intrinsically flawed.
Quote:
Originally Posted by
Feign
Also, at some point, it might be best to have a "reccomended sound card" list rather than try to make the printer work with every sound card under the sun. Heck, I remember one thread that I can't find now that someone found a DC coupled USB sound card for impressively little cost. Consider finding that or something similar and reselling it through the Peachy store.
I agree with this. You might be able to literally make it universally compliant with existing sound cards, but the next day someone in china will make a sound card with a higher SNR than you expect and the day after that someone in the US or EU will make one that has a completely different sampling rate. Just pick a best fit and let the community come up with further hacks and suggestions like this USB card or minor tweaks to the circuitry if it doesn't interface perfectly with their particular sound card.
Dampening and Analog vs Digital
Quote:
Originally Posted by
User_Defined
Youd have your input signal with a voltage proportional to what angle the mirror would be.
Next it would go to your amplifier circuit to drive the mirror.
From the mirror you would then have a positional measurement by the magnetoresistive sensor.
The error is defined by where the mirror actually is, and where you wanted it, and this signal is fed back to combine with the original signal to close the loop and subtract away the error. A system like this should auto dampen.
Yes, it would take care of any distortion in actual mirror position due to noise, or vibrations. However, what about the printing material itself? Just because you dampen the mirrors doesn't mean the resin isn't bouncing around. The resin has to be physically dampened somehow. Also, there are plenty of hall effect sensors that can be used in parallel as you are describing and in series with the coils as well. Not entirely sure what's different or special about that particular sensor from Honeywell other than the low power requirements.
Quote:
Originally Posted by
Aztecphoenix
The old ZX Spectrum computers were designed to use any tape deck that you had available rather than a model specific deck and took in the audio signal and converted it into binary code
This is possible, but doesn't really make any sense to do. If you have a sound port on a device that is capable of running the peachy's software, it should have a USB port as well. To go from analog to digital and back to analog you're going to need some sort of "processor". Which means that you honestly might as well just use USB. The problems that arise from different sound cards range from different noise levels to different output levels. Analog is precise, meaning the signal must be exact. Digital allows for a lot of wiggle room. There's no way to build a circuit that will always be compatible with every sound card. Plugging a laptop in will usually produce some noise on the line, resulting in a distortion in AM. Some sound cards that are on-board desktop cards have a significant amount of noise on them as well. If you own a phone that wasn't taken care of as well as it probably should have been it will likely not produce sound without some minor distortion that may be inaudible, but will affect AM.
