Powerburner:
General comments are great but if you haven't built one of these 1/65th X-15 PMC's, I can tell from your post you have not. Please be careful with your suggestions.
Smiffo:
Please ignore Power's comments on 13mm motors for this PMC,
unless you can find a 13mm AP B power motor, This model is beyond the lift limits of A motors period.
Sorry the low res pic is unreadable, I'll send a higher res pic by e-mail.
I'd add Asp and pratt hobbies to the Parts is parts question. or kit bash just about any 18mm small model kit you can buy cheap
This model comes with a 1 piece exhaust nozzle that will need some dremel work to widen slightly for a very nice fit with your standard 18mm body/motor tube. I used a EB-20A motor block but a 1/4" piece of 18mm engine casing will work just as well for your motor block/shock cord mount. tie 40" of 70 -100 lb kevlar to the motor stop before gluing in place 2.5" inside the aft end of the body tube. I used a friction fit for the motors for this model but you could cut a 3/16" slot in the body/tail cone for a motor hook if you want.
The way I cut PMC's for conversion is on a bandsaw, but a fine blade X-acto saw and mitre box will work fine. rubber band the model together with a least 2 bands on each side of the seperation point. Try to set the model in the miterbox with the body seams as horizontal as possible. I like to offset the top and bottom cuts by a 16th or so to form an auto lock to keep the nose from sitting out of alignment.
Centering the BT-20 in the body is done with scrap strips and short pieces cardstock. tack with a tiny drop of CA or even carpenters yellow glue.. this is only a temporary holding point so keep it very light, you may need to move the shim. When your happy with the centering and fit epoxy the tube/shims in place inside the plastic body. let completely set up before moving on to the nose cone.
Install the clear window plasitc. I used a 19mm Slip-over tube in the nose section to save recovery system space, but a nose plug could also be used after adding the nose weight, 27grams is required to allow this model to fly on B4-4's thourgh C6-7 motors. BB's, lead fishing weight etc are fine, get them as far forward as possible. Check the C.G with the cutout provided. My model recovers on a 12" standard plastic chute.
OBTW I'd suggest only flying this one with C6's on very clear calm days...She really gets up there and will drift a LONG way
Hope this helps