JimJarvis50
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It used to be that one of my least favorite things to do was to glue together CTI 98mm motors. The process is to apply Gorilla Glue to a grain and insert it into the end of the liner. Then, you add one of the spacer o-rings, apply glue to the next grain and push it in, and then repeat until all of the grains are inserted. Towards the end of the process, you have to push all of the grains into their final position at the end of the liner. It's a race to get that done before the glue sets up. The directions used to say to dampen the grains to help the glue set up. If you did that, you'd lose the race (ask me how I know that). The directions were changed a few years ago at my suggestion to omit the dampening step, but it is still an exciting process when you get to the last few grains.
In my recent assemblies, I have modified the procedure to make the process less stressful. In a nutshell, I glue the little spacer rings to the grains in advance. Then, when the glue is applied to the grains, they can be pushed all of the way to the bottom of the liner. Thus, you don't have to worry about the grains getting stuck before they are all inserted. I've done this on a half dozen or so CTI motors, as have others, and the process has worked well as have all of the motors assembled in this manner. You're welcome to try my technique, and as Stu Barrett would say, your mileage may vary.
To glue on the spacer, I first clean off the spacer with alcohol and then scuff it up with some sandpaper. Then, I apply a bead of epoxy around the edge of the grain, and then I wrap the top of the grain with a piece of mylar. Finally, I put the o-ring inside the mylar and tap it down into the glue. Once the glue cures, you can assemble the motor.
Jim
In my recent assemblies, I have modified the procedure to make the process less stressful. In a nutshell, I glue the little spacer rings to the grains in advance. Then, when the glue is applied to the grains, they can be pushed all of the way to the bottom of the liner. Thus, you don't have to worry about the grains getting stuck before they are all inserted. I've done this on a half dozen or so CTI motors, as have others, and the process has worked well as have all of the motors assembled in this manner. You're welcome to try my technique, and as Stu Barrett would say, your mileage may vary.
To glue on the spacer, I first clean off the spacer with alcohol and then scuff it up with some sandpaper. Then, I apply a bead of epoxy around the edge of the grain, and then I wrap the top of the grain with a piece of mylar. Finally, I put the o-ring inside the mylar and tap it down into the glue. Once the glue cures, you can assemble the motor.
Jim