Master Roda
01-30-2012, 10:01 AM
I decided to start this thread as a way to answer some questions about Sport Rotors that you may have.
I build the rotors for Sport Copter. I have been for a long time (it seems like). Over the years I have done my best to streamline the system that Jim Vanek built. I've increased the efficiency of the system, and made adjustments that have improved the end product. I don't do it alone. I have a couple of helpers, and they do a fantastic job.
Without letting secrets go I'm going to do my best to describe what actually goes into a set. And maybe answer the question "why do they take so long?".
First, the materials are sourced from manufacturers that can provide documentation that certifies it. If we can't get that, we don't use it. 6061 T6 is what we use for the majority of construction. It was chosen as the best material to extrude and give the longest life for our purpose. The extruded section is scrutinized for any kind of twisting or deformations. The same for the sheet metal skins that comprise the majority of the airfoil. Sometimes the sheet metal has ripples in it due to fact that it came from the end of a roll. We can't help this and you'll sometimes see it in the rotors finish (I hate it).
The components are precision cut and processed (drilling/milling). Then they are weighed and paired for each set to within 2 grams. With each set a traveler is assigned that documents the entire process of manufacture. The weights, lengths, temperature, humidity, and times are all documented.
With a paired set we process the materials through the bonding process. I can't say much about that, but we document the entire process. We also process a small sample through with each set and test it for conformity after the process. This sample is kept as proof of the successful bond. The bond has been tested by independant labs and myself to 5 tons per square inch sheer. If you've ever seen a set of crashed Sport Rotors you'll see that the bond line never breaks (unless the metal tears). We keep a few sets of crashed rotors here at the shop to show customers. Visible proof is always better.
After the bonding process they are finish sanded and re-weighed. This process is also documented. There is actually alot that goes into sanding them. The tips are rounded BY HAND. This job requires alot of skill and patience. That job is handled by one of the helpers and I have never had a hand in that part of the process.
When two sets have been finish sanded I paint them. Before the paint, I seal the bond lines with structural epoxy. Then they are washed and treated with an adhesion promoter. Next I apply the primer, but not just any primer. This primer is an aerospace primer designed for rotors. It passes what they call a whirling arm test. It isn't cheap and it's a pain in the butt. You can't just mix it and spray. It involves a lengthy dwell time and time to topcoat. Finally, when the primer is ready to topcoat, I spray on the white polyurethane topcoat. To accelerate the curing process I heat them up in our large oven at the prescribed temperature and time by the manufacturer of the paint (PPG). Before we built the oven we had to wait weeks to assemble them. The oven was built about 5 years ago.
The hub bars are CNC machined 6061 T6. The other materials are a trade secret. We use all AN and NAS hardware. Everything in the hub is either plated, anodized, or protected in some way. I personally build each one to assure precision and quality. Mistakes at this point are unacceptable. I have implemented a system of checks and balances to assure this.
I assemble the rotor system with an aircraft lubricant to assure everything goes together smoothly and stays protected. The system is balanced (within 1/10 of a gram) , checked for proper pitch and lead/lag positioning. The center barrel is centered with a dial indicator. If it isn't centered perfectly it won't fly well. Again, the process is documented.
FLY!! This is the fun part. Either Jim or myself (or both of us) will test fly the set documenting the conditions of the day and how well the rotors fly overall. We even rate each set. This is important. We know for sure that the set is good before it goes to the customer, and any complaints are usually solved with the customer finding something wrong with their machine.
Finally, I pack the set and ship it. Sometimes the shipping company runs forks into the side of the box and I get to start all over.........
Questions?
I build the rotors for Sport Copter. I have been for a long time (it seems like). Over the years I have done my best to streamline the system that Jim Vanek built. I've increased the efficiency of the system, and made adjustments that have improved the end product. I don't do it alone. I have a couple of helpers, and they do a fantastic job.
Without letting secrets go I'm going to do my best to describe what actually goes into a set. And maybe answer the question "why do they take so long?".
First, the materials are sourced from manufacturers that can provide documentation that certifies it. If we can't get that, we don't use it. 6061 T6 is what we use for the majority of construction. It was chosen as the best material to extrude and give the longest life for our purpose. The extruded section is scrutinized for any kind of twisting or deformations. The same for the sheet metal skins that comprise the majority of the airfoil. Sometimes the sheet metal has ripples in it due to fact that it came from the end of a roll. We can't help this and you'll sometimes see it in the rotors finish (I hate it).
The components are precision cut and processed (drilling/milling). Then they are weighed and paired for each set to within 2 grams. With each set a traveler is assigned that documents the entire process of manufacture. The weights, lengths, temperature, humidity, and times are all documented.
With a paired set we process the materials through the bonding process. I can't say much about that, but we document the entire process. We also process a small sample through with each set and test it for conformity after the process. This sample is kept as proof of the successful bond. The bond has been tested by independant labs and myself to 5 tons per square inch sheer. If you've ever seen a set of crashed Sport Rotors you'll see that the bond line never breaks (unless the metal tears). We keep a few sets of crashed rotors here at the shop to show customers. Visible proof is always better.
After the bonding process they are finish sanded and re-weighed. This process is also documented. There is actually alot that goes into sanding them. The tips are rounded BY HAND. This job requires alot of skill and patience. That job is handled by one of the helpers and I have never had a hand in that part of the process.
When two sets have been finish sanded I paint them. Before the paint, I seal the bond lines with structural epoxy. Then they are washed and treated with an adhesion promoter. Next I apply the primer, but not just any primer. This primer is an aerospace primer designed for rotors. It passes what they call a whirling arm test. It isn't cheap and it's a pain in the butt. You can't just mix it and spray. It involves a lengthy dwell time and time to topcoat. Finally, when the primer is ready to topcoat, I spray on the white polyurethane topcoat. To accelerate the curing process I heat them up in our large oven at the prescribed temperature and time by the manufacturer of the paint (PPG). Before we built the oven we had to wait weeks to assemble them. The oven was built about 5 years ago.
The hub bars are CNC machined 6061 T6. The other materials are a trade secret. We use all AN and NAS hardware. Everything in the hub is either plated, anodized, or protected in some way. I personally build each one to assure precision and quality. Mistakes at this point are unacceptable. I have implemented a system of checks and balances to assure this.
I assemble the rotor system with an aircraft lubricant to assure everything goes together smoothly and stays protected. The system is balanced (within 1/10 of a gram) , checked for proper pitch and lead/lag positioning. The center barrel is centered with a dial indicator. If it isn't centered perfectly it won't fly well. Again, the process is documented.
FLY!! This is the fun part. Either Jim or myself (or both of us) will test fly the set documenting the conditions of the day and how well the rotors fly overall. We even rate each set. This is important. We know for sure that the set is good before it goes to the customer, and any complaints are usually solved with the customer finding something wrong with their machine.
Finally, I pack the set and ship it. Sometimes the shipping company runs forks into the side of the box and I get to start all over.........
Questions?