- Joined
- Jul 3, 2017
- Messages
- 233
- Reaction score
- 79
Hi Everyone,
Sorry that I wasn't able to respond to a few questions in a timely manner. My computer's mother board and hard drive mysteriously fried after restating the computer after a Microsoft update. Our company IT Guy had to get me a new computer.
Someone asked what avionics I was going to be using. I am waiting for Vern Knowles, multitronix.com, the maker of the "Kate" GPS tracker unit to release his staging altimeter. Vern's altimeter's initiall specs can be found on his website. This unit has a built in shunt, an attitude sensor that will prevent the sustainer from firing if the sustainer is angled too many degrees off of vertical. The staging unit has a staging seperation charge firing function. The unit also has a primary and secondary firing function for both the drouge and main parachutes. Vern's unit will communicate with the Kate unit. The Kate unit will then provide realtime data to your Kate ground receiver about all of the altimeter's functions.
In the booster I will have a Missile Works simple RRC2+ to fire off the drouge parachute at apogee. I will use the motor charge as a backup. The Missile Works RTx GPS System will provide tracking for the booster. I was going to use the Missile Works PET2+ in the booster to fire off the separation charge. Unfortunately I cannot fit the RRC2, RTx GPS Tracker, and the PET2+ all into the 54 mm Wildman interstage AV Bay.
Tim at Wildman recommended that I not redesign his kits interstage. Since this is my first high power two stage I am following his advice. I had a choice of either fitting the Missile Works GPS Tracker or the PET2+ with the altimeter. Since the Multitronix stager has a seperation charge firing capacity, I will fire off the seperation charge from the sustainer. There was enough room in the sustainer to install a second 3/16" break line tube to snake down a feeder wire for the seperation charge.
Unfortunately I didn't have time to start a build thread for this project. However I can mention a few modifications that I made to the Wildman 3" two stage kit. Someone might find them useful. First off the kit comes with only two thin fiberglass motor centering rings for each stage. Tim's 2009 online instructions show three motor centering rings. I purchased three 1/2" plywood centering rings for each stage from Tim at Wildman.
The thick plywood rings are easier to properly lineup for alignment purposes. They also provide a greater mating surface for the epoxy. By using three centering rings instead of two, I was able to build the booster with internal fin to motor tube and fin to booster tube fillets. I'm sure that Tim's internal injection fillet method works fine. However I was just more comfortable securing the fins in the traditional method. I was also able to fill the boosters fin can with expanding foam.
Wildman provides a Kevlar strap for a parachute attachment point. Tim's instructions have you file a notch in the motor centering rings. Wildman then tells you to epoxy the Kevlar strap to both sides of the motor tube. I'm sure that this works fine. However I like Mike Crupe's attachment method better. Mike is the owner of MAC Performance. I have five of his kits. If you haven't tried building one of his kits you should. The fit of all of the components in Mike's kits is amazing.
MAC Performance uses a notch in a 3/8" plywood centering ring. A Kevlar Harness strap with a small loop on one end and a larger loop on the parachute side of the Harness is provided in his kits. A steel pin is epoxied through the small loop and notch in the centering ring. This produces an upside down "T" which is trapped under the forward centering ring, body tube, and motor tube.
On my two stage 3" Wildman build I purchased two of the MAC Performance Harness attachment systems. I epoxied the MAC Performance Harness centering ring on top of the 1/2" Wildman plywood centering ring. This gave me a 7/8" plywood forward centering ring. My Kevlar Harness is completely epoxied into this massive ring. The main benefit of this Harness attachment method is that it is way less messy than the Wildman method. A second benefit is that there isn't a lot of extra real estate on the motor tube when you are installing three fins, two 3/16" brake lines and the two Kevlar straps.
All the best,
Bob
Sorry that I wasn't able to respond to a few questions in a timely manner. My computer's mother board and hard drive mysteriously fried after restating the computer after a Microsoft update. Our company IT Guy had to get me a new computer.
Someone asked what avionics I was going to be using. I am waiting for Vern Knowles, multitronix.com, the maker of the "Kate" GPS tracker unit to release his staging altimeter. Vern's altimeter's initiall specs can be found on his website. This unit has a built in shunt, an attitude sensor that will prevent the sustainer from firing if the sustainer is angled too many degrees off of vertical. The staging unit has a staging seperation charge firing function. The unit also has a primary and secondary firing function for both the drouge and main parachutes. Vern's unit will communicate with the Kate unit. The Kate unit will then provide realtime data to your Kate ground receiver about all of the altimeter's functions.
In the booster I will have a Missile Works simple RRC2+ to fire off the drouge parachute at apogee. I will use the motor charge as a backup. The Missile Works RTx GPS System will provide tracking for the booster. I was going to use the Missile Works PET2+ in the booster to fire off the separation charge. Unfortunately I cannot fit the RRC2, RTx GPS Tracker, and the PET2+ all into the 54 mm Wildman interstage AV Bay.
Tim at Wildman recommended that I not redesign his kits interstage. Since this is my first high power two stage I am following his advice. I had a choice of either fitting the Missile Works GPS Tracker or the PET2+ with the altimeter. Since the Multitronix stager has a seperation charge firing capacity, I will fire off the seperation charge from the sustainer. There was enough room in the sustainer to install a second 3/16" break line tube to snake down a feeder wire for the seperation charge.
Unfortunately I didn't have time to start a build thread for this project. However I can mention a few modifications that I made to the Wildman 3" two stage kit. Someone might find them useful. First off the kit comes with only two thin fiberglass motor centering rings for each stage. Tim's 2009 online instructions show three motor centering rings. I purchased three 1/2" plywood centering rings for each stage from Tim at Wildman.
The thick plywood rings are easier to properly lineup for alignment purposes. They also provide a greater mating surface for the epoxy. By using three centering rings instead of two, I was able to build the booster with internal fin to motor tube and fin to booster tube fillets. I'm sure that Tim's internal injection fillet method works fine. However I was just more comfortable securing the fins in the traditional method. I was also able to fill the boosters fin can with expanding foam.
Wildman provides a Kevlar strap for a parachute attachment point. Tim's instructions have you file a notch in the motor centering rings. Wildman then tells you to epoxy the Kevlar strap to both sides of the motor tube. I'm sure that this works fine. However I like Mike Crupe's attachment method better. Mike is the owner of MAC Performance. I have five of his kits. If you haven't tried building one of his kits you should. The fit of all of the components in Mike's kits is amazing.
MAC Performance uses a notch in a 3/8" plywood centering ring. A Kevlar Harness strap with a small loop on one end and a larger loop on the parachute side of the Harness is provided in his kits. A steel pin is epoxied through the small loop and notch in the centering ring. This produces an upside down "T" which is trapped under the forward centering ring, body tube, and motor tube.
On my two stage 3" Wildman build I purchased two of the MAC Performance Harness attachment systems. I epoxied the MAC Performance Harness centering ring on top of the 1/2" Wildman plywood centering ring. This gave me a 7/8" plywood forward centering ring. My Kevlar Harness is completely epoxied into this massive ring. The main benefit of this Harness attachment method is that it is way less messy than the Wildman method. A second benefit is that there isn't a lot of extra real estate on the motor tube when you are installing three fins, two 3/16" brake lines and the two Kevlar straps.
All the best,
Bob