While I am somewhat of a rookie in my return, I have built a LOT of rockets in my day. This kit has the first set of directions that if followed, seem to end in an unusable rocket.
There are no instructions on prep work for the reducer - it comes molded solidly, with 38mm and 54mm cutaway marks engraved into both ends. In this case the MMT is longer than the main BT, and thus passes THROUGH the reducer. Seeing as it's a 38mm MMT, I cut away the 38mm cut outs in both sides of the reducer (again, there is nothing mentioned in the instructions regarding the work that has to be done on the reducer).
The instructions have you glue the forward centering ring 1-1/8" from the front of the MMT, and then a larger mid-ship CR at 10-1/2" from the front. The rear most CR goes behind the fins - standard stuff.
So I have the forward CR heavily epoxied to the MMT, the MMT passes through the reducer (which is still unglued to the MMT per the instructions), and the mid-ship CR is also heavily epoxied to the MMT.
Here's where the problem is, the position of the forward CR dictates the position of the reducer - i.e. it can't slide any further forward as the forward CR acts as a "stop" for the shoulder of the reducer. There's a 1/16" gap between the forward CR and the front of the reducer shoulder due to the heavy epoxy fillet on the bottom of the forward CR (not really critical, but added for sake of full disclosure).
Given this "all the way forward" position of the reducer, if the main BT is slid all the way on to the lower reducer shoulder, the MMT is 3/4" UP inside the rear of the main BT - above even the rear of the fin slots. Obviously this position of the MMT renders the current assembly unusable.
There are two fixes that I perceive:
1) Cut approximately 1" from the upper shoulder of the reducer, so that it can slide forward further. This, of course reduces the structural integrity as there is no positive location for the forward end of the reducer, but would allow for the current assembly to be used. Another side effect is that it changes the weight distribution - albiet slightly - of the rocket.
2) Obtain replacement parts from LOC, and start over - with a different position for the forward CR. That's really where I need help from the group here....
In reviewing other LOC instructions, I have come to the conclusion that the problem begins with the kit's instructions, and the location of the forward CR, instead of 1-1/8", I'm guessing it should more likely be 1/8" - this would move the reducer forward by 1" and thus the lower part of the MMT would extend beyond the main BT by 1/4" - about what is shown in the instructional diagram (no measurements are provided).
I checked the instructions on two other LOC kits that I had, and both had the forward CR 1/8" from the end of the MMT - not that that should be used as the basis to change the instructions of a kit, but it certainly would fix the problem that I'm having.
I have already requested replacement parts from LOC, and I believe they are providing them (haven't received confirmation of that yet), so this will get fixed - what I'm really wanting is to hear from somebody else that's gone down this road. Surely somebody else has run into this problem, or has done something differently that can tell me the error of my ways?
I'm not above believing that I've made a mistake, but I've checked and re-checked the instructions, the measurements on the parts, etc. and just can't find where I've gone wrong.
Thanks!
Paul
There are no instructions on prep work for the reducer - it comes molded solidly, with 38mm and 54mm cutaway marks engraved into both ends. In this case the MMT is longer than the main BT, and thus passes THROUGH the reducer. Seeing as it's a 38mm MMT, I cut away the 38mm cut outs in both sides of the reducer (again, there is nothing mentioned in the instructions regarding the work that has to be done on the reducer).
The instructions have you glue the forward centering ring 1-1/8" from the front of the MMT, and then a larger mid-ship CR at 10-1/2" from the front. The rear most CR goes behind the fins - standard stuff.
So I have the forward CR heavily epoxied to the MMT, the MMT passes through the reducer (which is still unglued to the MMT per the instructions), and the mid-ship CR is also heavily epoxied to the MMT.
Here's where the problem is, the position of the forward CR dictates the position of the reducer - i.e. it can't slide any further forward as the forward CR acts as a "stop" for the shoulder of the reducer. There's a 1/16" gap between the forward CR and the front of the reducer shoulder due to the heavy epoxy fillet on the bottom of the forward CR (not really critical, but added for sake of full disclosure).
Given this "all the way forward" position of the reducer, if the main BT is slid all the way on to the lower reducer shoulder, the MMT is 3/4" UP inside the rear of the main BT - above even the rear of the fin slots. Obviously this position of the MMT renders the current assembly unusable.
There are two fixes that I perceive:
1) Cut approximately 1" from the upper shoulder of the reducer, so that it can slide forward further. This, of course reduces the structural integrity as there is no positive location for the forward end of the reducer, but would allow for the current assembly to be used. Another side effect is that it changes the weight distribution - albiet slightly - of the rocket.
2) Obtain replacement parts from LOC, and start over - with a different position for the forward CR. That's really where I need help from the group here....
In reviewing other LOC instructions, I have come to the conclusion that the problem begins with the kit's instructions, and the location of the forward CR, instead of 1-1/8", I'm guessing it should more likely be 1/8" - this would move the reducer forward by 1" and thus the lower part of the MMT would extend beyond the main BT by 1/4" - about what is shown in the instructional diagram (no measurements are provided).
I checked the instructions on two other LOC kits that I had, and both had the forward CR 1/8" from the end of the MMT - not that that should be used as the basis to change the instructions of a kit, but it certainly would fix the problem that I'm having.
I have already requested replacement parts from LOC, and I believe they are providing them (haven't received confirmation of that yet), so this will get fixed - what I'm really wanting is to hear from somebody else that's gone down this road. Surely somebody else has run into this problem, or has done something differently that can tell me the error of my ways?
I'm not above believing that I've made a mistake, but I've checked and re-checked the instructions, the measurements on the parts, etc. and just can't find where I've gone wrong.
Thanks!
Paul