Here is the latest update about the 4 new prototypes. To produce the 4 new prototypes, we worked with 4 main factories, herein referred to as A/B/C/D, to produce the bespoke components. For the standard parts, we bought online.
1. Factory A – Produces all the plastic components of the 4 prototypes, including the shell, the transparent PC frame at the bottom, the base, the filament box, etc.
2. Factory B – Produces 2 sets of the components that need to be CNC machined, including the supporting column, timing belt fixture, hexagon print head base, aluminum alloys work table for the CNC module, etc.
3. Factory C & D – Produces the other 2 sets of CNC machined components. C is in charge of the easier components while D is in charge of the difficult ones.
Upper frame without shell
Upper frame with shell
This decision is made after an overall consideration and inspection of each factory’s scale, lead time, price, professionalism, standardization, etc. As of today, we have received 95% of the components from factory B, C, & D, and 1 set of the plastic components from A, except the transparent PC frame at the bottom. All of these components have been verified and passed our first-round test.
The problem we are facing now is that we need another 3 sets of plastic components and 4 pcs of transparent PC base. Factory A did produce most of the plastic components, but they cannot meet our standards and failed our test so we didn’t take those components. After this cooperation, we realized that factory A cannot meet our standards both in terms of yield rate and the degree of cooperation. We found the quality problem about one week ago and asked them to modify accordingly yet they failed and refused to modify again. To avoid the similar problem, we are outsourcing the rest of the 3 sets of plastic components to two different factories, factory E & F. Factory E will produce 1 set and factory F will produce 2 sets. We are expecting to get the rest of the components ready for the 4 prototypes in about 7 to 10 days’ time. In the meantime, we will start assembling the upper parts of the prototype and drafting the assembly process.
When cooperating with factory B, C & D, we also found two major problems.
1. The lead time. Usually, there are 3 days to 1 week’s delay in the promised lead time. If there is any major quality problem or processing mistakes, the delay could be longer. The actual reliability, responsiveness, and punctuality of a supplier can only be verified after we have worked with them. This time, factory B & D have all past our standards and we will continue working with them when producing the 20 units.
2. The yield rate. The yield rate is another key factor when choosing the supplier. In this cooperation, some of the defective components were caused because our instructions or requirements were not clearly expressed to the supplier. Our engineers and purchasing staff will be more careful in the future to avoid similar problems. Some other quality problems were caused by the processing process of the factory. This can be solved by a) choosing the right supplier that has a high standard themselves; b) working closely with the supplier to ensure and improve the yield rate gradually. We will have a more fixed yield rate standard when we start the trial production of the 20 units.
Below is our testing plan for the following month.
1. Testing period: The prototype testing will last for at least 30 days to ensure its comprehensiveness. It will be divided into 4 stages, and every stage will last for about 1 week.
2. Testing segments: Static testing, motion testing, and printing testing.
A. Static testing includes printer dimension, assembly positioning, printer rigidity, control board (ESD & temperature resistance), sensor signal, continuous extrusion test of the extruder and print head, power port plug test, pogo-pins test, aging test of the laser diode, the filament feeder sensor, and power switch, repeatability of the closed-loop motor, etc.
B. Motion testing includes motion speed, acceleration & deceleration vibration, motion noise, motion gap, the kinematic error of single repeatability, kinematic error of multiple repeatabilities, operating error of the cooperation of the XYZ motors, etc.
C. Printing test includes printing quality uniformity of the same model, printing test of different models, printing test of different filaments, printing test of different nozzles and different layer heights, nonstop printing test, etc.
We will prioritize the tests that will influence the dies & molds making and complete these tests first to start the dies & molds creation early. During the test, if there are key components replaced/modified, we will run the same tests for the new components again thus the total testing period will extend as well.
The overall goal of the 1-month testing is to confirm the feasibility of IVI’s structural design, detect the potential risks for mass production, start creating extrusion dies and molds and be ready for the trial production of the 20 units.
After we start the testing, we will have a weekly or biweekly update on the testing and progress, which should start from the second week of Oct. Thank you all for your patience and understanding. Together, we make IVI better.