Blog #31: Still shipping, Improving Quality Process, V2 Hollow Wheel Improvement
I am still shipping. Shipping has been very slow and tedious. Not the way I wanted to launch, but I had discovered a potential quality defect that has caused me to inspect every wheel before I ship. On many wheels, we discussed in some cases inadequate bonding between the core and the tread. Some more than others. So it literally is taking me up to 30 minutes to ship each regular wheel. I have not slept this little or been this stressed out ever. Each day, I am inspecting wheels, doing durability inspection tests on my test rig, answering customer support emails, and shipping and packaging. I wish I could hire some people to help but I need to reserve the capital to improve the product more - changing molds and ordering more inventory.
This has been one of the biggest personal milestones that I have accomplished in recent years and I am so proud and determined. While the potential issues have taken a bit of wind out of my sails, I am determined and won't give up to deliver the very best product. Many of the large skateboard manufacturers declined the project because electric skateboards is a very small market compared to longboards and typical skateboard, but I want to continue to innovate in this small community of people that have the same passion as me. So the factory in China is a small but very hungry team and we are working day and night to fix this.
I am also taking this negative and turning it into a positive by taking this as a chance to invest more and improve the product. I cannot complete this project without you guys and if we stick together, we can make this project possible. I know you guys can see that I have been executing, providing customer support, and I just want to say that I won't and can't stop but I just need your patience and support.
What is happening? Ultimately, there was an issue with the material interaction between the core and the tread.
The core is the white part. The black part is the tread.
In this case, the core is placed inside a mold as a solid, cold part, and the tread is injected into the mold as a hot liquid. This creates melting of the two materials as the hot liquid is injected into each other at high pressure and temperature. There must be certain preparations in order for the core to be clean.
What causes the problem to happen?
If there is inadequate chemical bond, as heat generates the material gets weaker and wants to flex more. The more flex it has, the more that there can be relative movement between core and the tread. When there begins to be the very slightest hint of relative movement, then the core and tread will soon separate.
As this is a first batch production and a new set of challenges arise, there are always things we will continue to improve. At scale, material processes will be better defined and controlled. Its an evolving process.
Can I upgrade to PRO?
The PRO is safe to ride and unaffected as the materials are vastly different and have inherently better chemical adhesion performance. require different injection molding procedure. However, the load capacity (190lbs) on the PRO is less so than the material used in Comfort. The load capacity will increase over time as I gather more data but for now, I am being conservative.
What am I doing to fix the problem?
I am creating a V2 Hollow Wheel. I am doing three main things to improve production efficiency:
- Working with injection molding factory, material suppliers to test new process to avoid delamination. Completion: 10-28-22
- Conduct mold modifications to improve production efficiency and also integrate performance changes based on user feedback. Completion date, estimated: 11-26-22
- V2 Hollow Wheel batch to be completed with production and boarding a shipping container to USA. Completion date, estimated: 12-20-22
Item 1: Material testing and improvements
Current status: Real-world testing & test rig validation testing. Should be complete in 2 weeks.
We have decided to move away from the raw material supplier but source the same type of material from more reputable sources. We know the chemical compound to work very well, but the problem with the original supplier is that they were not able to provide adequate data on the production process related to QA.
We are running new injection tests on 3 different materials using the same molds. Then, we will conduct quick tests to determine if there is an improvement on delamination. If there is, we will be shipping the wheels (8 sets) to our durability testers.
Update: I have received the wheels. The bonding strength with new manufacturing supplier and improved processes have drastically improved.
See video here of a factory worker trying to separate the wheel, pulling apart the wheel but there is excellent bonding and no separation that can be seen.
Youtube short (10sec): https://youtube.com/shorts/8D9TZtChjoA?feature=share
We have only 8 individual wheels so I have sent it to a heavy rider (270lb) and I am running tests on the test rig (see below)
Although, we only have 8 individual wheels, the test rig is able to replicate road conditions accurately. I will be running 8
Item 2: Mold changes to improve performance and production efficiency
Current status: Awaiting results from Item 1. Should commence in about 2 weeks, machining of new parts, which will take 30 days to complete.
After we prove that the new materials from the new material suppliers bond better, I will take the opportunity to incorporate changes to improve the mechanical locking between the core and the tread as well as provide improvements to the wheel.
We are going to stiffen the area around the core. So we will increase the thickness of the tread around the core as well as add more mechanical locking features to make sure that area can handle higher stress and strain.
As far as the fixes are concerned. Here is the new design of the wheel wherein the main goal is to increase the stiffness between the wheel and the core. More material stiffness means less likelihood for delamination.
I will be also improving some things related to:
- Bearing fitment - some complaints that it is too tight
- Slightly reduce negative camber - this will mean more grip
Customers above a combined weight of 200lbs+ (rider+gear+board), I have three options:
- Hold onto your order and I'll provide you $30 worth of free belts or bearings (any of your choosing) to get V2 Wheels.
- Provide full refund for those that have not
- I can ship you the V1 Wheels now but no refunds will be eligible. I strongly do not recommend option 3. In a few months, you’ll receive a much better V2 Wheel; don’t pick option 3 if you’re over (body+board weight+gear) 200lbs.
I am highly encouraging people to take option 1 because I know this project will be a success and I cannot do this project without you guys. Know that I am 100% dedicated to seeing this project all the way through and providing the very best product.
If you pick option 1, you’ll get V2 of the Hollow Wheels with improved durability and improved grip performance. The comfort will stay the same, which these are very comfortable to begin with - just ask any Hollow Wheel user what they think.
Please contact me of your decision. If I do not hear back, I will assume you want option 1.
For people under 200 lbs (rider + gear + board),
I will continue to ship. Should anything happen, I will provide you a full refund or new replacement.
Please let me know if you fall into this category.
If you are under the 190lb (board + body weight), then I will upgrade you for free upon request.
Random Reviews of Hollow Wheels that I captured on Social
More reviews here:
Durability Testers Needed:
My go to durability tester is no longer available and cannot put in the time to help ride. I need help from someone that is 220-250lbs. I'm looking for about 3-5 people. I will refund your orders and supply you with wheels to test.
In particular, I am looking for those who rides a lot, carves a lot, and lives in a warm/hot climate where they can put on 100 miles inside each week.
Kindly fill out this Google form to be eligible: https://docs.google.com/forms/d/e/1FAIpQLSdgxLtJK_PeF3KkxTTZWoMxvS1xrs-W6KC0urRnAT3txVXXGg/viewform
Momentum China & New Investment
I have gained a new partner/investor in China that will help with cash injection to help fund the new set of molds for V2. Moreover, I have been working with my partner, Yuan, during the entirety of this project and he has been instrumental in bringing this project to this stage. He has seen the dedication and effort I have put in and wanted to help back the project. He has been responsible for helping manage the factory overseas as well as the material suppliers. Without him, I could not have done it. With his help, he will help me bring the project to new heights.
Thank you for your patience. Sorry it is taking so long. If we stick this through, we will make improve the community for the better. I am 100% dedicated to the success of this project.
Feel free to ask me any questions.