Love the SB! My son will be building his too for Jr L1! Will be watching. I have anSB booster finished but decided to stretch it a little
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Looks good so far,
a few questions though..
1) did you glue both CRs to the MMT? Leaving off the rearward CR, allows you to easily get inside and add internal glue fillet.
2) did you add a fillet to the top & bottom of the CR(S)?
3) have you ensure the nut on the back of the eye-bolt is 'locked' (either with loc-tite, glue, pinched threads, etc..) and, I personally prefer to use a nut & washer both top & bottom of the eye bold. much better / more solid locking / securing to the CR.
4) what kind of knot did you use to secure your shock cord?
I don't think you needed to peel the other layer off the MMT. I good hard sanding should suffice. At Least, that's what I do, and so far no issues..
I prefer 'T' nuts (or 'blind nuts') for threaded features in wood. easier to use, less glue & such, and more area for pull-put strength..
Buttons? add a bit of wood to the CRs, so you have more 'meat' to aim for when you get to that point..
Andrew,
Good luck on your build and Jr. L1 certification flight! I will be following your build with interest as I also have built a SB in the past. Will you be finishing it in black and silver, or something else?
This is what Dr. Wogz was talking about - blocks on the centering rings to screw the rail buttons into. Don't know if it's too late though.
Yeah, it's too late to do that..
Thanks,
I've gotten to where I peel all of my MMT as well. It's easy and none of that "Is it scuffed enough".
Don't you guys worry that you get too loose a fit? and rely on a thick (relative!) layer of epoxy between the two?
I just used a simple knot. I reinforced it with some glue. The eyebolt holding it is very secure with a washer and a nut, and it has also been glued for extra security.What did you do about that knot? Kevlar probably would have been better. I find those cords from Madcow last about 5-6 flights.
Judging by your photos it’s finished? When’s the maiden flight?
How about I throw a Jolly Logic Chute Release in there for the I motor?Since it's single deploy I would do the CTI. Definitely not the I, that's going to be really hard to keep an eye on.
Looking good Andrew!
My son is Andrew too - he is building his for 4-H so likely maiden flight in fall.
Your Batray has a different Nose cone, but otherwise identical to my L1 even down to the epoxy and I flew mine numerous times until a zipper - that is when I stretched it and turned into dual deploy.
We may decide to fly in OH once complete depending on schedule. Probably H244 or the like to start with - stretched mine was not good anything less than an H195 - flew really nice I-180.
For reference.
Stock form - H128 DM was about 1100’
Stretched DD - H195 - 1050’
You seam to be the guy that likes to push things so I’ll be interested to see what you put in yours! Hope you post when you are going to fly - if our schedule permits - we will try to come to OH and join in the fun
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Yeah, it's too late to do that..
Thanks,
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