# Copying a Kit

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#### Who_Cares

##### Active Member
Good attitude. If you aren't sure it is safe don't fly it.
I think I may try it at some point in time. Maybe by sanding off the paint for the entire airframe and wrapping the whole airframe in fiberglass to cover the pre-cut fin slots, then adding new fins on top of the fiberglass and using tip to tip.

#### Who_Cares

##### Active Member
If you want to save the rocket , take a belt sander or random orbital sander or dremel and remove all the old epoxy and plywood that protrudes from the surface . You will then need to rotate your new fin slots 60 degrees from the old ones . Cut new fins out of 1/4 inch 7 ply , can be sourced at most hobby craft stores , and install them with good epoxy . Then you can lay some automotive fiberglass , 5 dollars , to seal the airframe where your old fins protruded and reinforce your fins . Add another J270 and your good to go . I did this on a Binder Design Excel Plus that sheared a fin off and cracked another .
A solid idea, and I could combine the reinforcement of the airframe with tip to tip reinforcement.

#### Who_Cares

##### Active Member
Email LOC. Tell em you need some 1/4" fins and a coupler, maybe a stiffy too, along with all the bits needed to make a new fin can...only 54mm this time, they'll slot the tube for ya. Mechanically attach the fin can so it can be removed if need be (not necessary but why not). Bevel the fins. Build it solid, don't need a tank.
I've flown my Binder DesignTyrannosaur on a CTI K600, RRC3 reported 1400+ ft/s, not sure if that was accurate though.
Just be sure your fin can is well built.
How would you attach a non permanent fin can?

#### JohnCoker

##### Well-Known Member
TRF Supporter
Plywood fins can be made easily by hand. Hobby shops carry high-ply plywood sheets in various thicknesses and sizes as small as 12" square.

Tubes can be purchased from a variety of places. Consider phenolic for a rocket that will be flown a lot because it is more durable than cardboard and can be worked with hand tools.

I put together a comparison of airframe materials which might be helpful:
jcrocket.com/body-tubes.shtml

#### captbk

##### Well-Known Member
What ever airframe you decide on make sure it's compatible with your LOC nose cone. Just sayin.

#### beeblebrox

##### 8 C6-0, 12 D11-9, 20 D20-0, 20 E5-0, 3 Cinerocs
AMWPROX has LOC 5.56" V2's and the stretch version on sale... \$110 for stretch version, 38mm mount perfect for L2... waiting on my order now! cant beat that with a whip!

#### MikeyDSlagle

##### Well-Known Member
How would you attach a non permanent fin can?
Glue the coupler into the fin can leaving at least a caliber sticking out. Inside the coupler put wood blocks to accept threaded inserts or T nuts, epoxy them if you'd like. You can use removable rivets (without the wood blocks) or self tapping screws, I just prefer machines screws with the inserts.
I slide the airframe onto the coupler, drill the holes, then remove the airframe so I can work inside the coupler.
Seriuosly, consider stepping up to 54. 38mm is good for getting your L2 but not for an honest to God L2 rocket. While there is a plethora of J motors, L2 goes beyond J, and how many Ks or Ls are in 38mm? The answer is 2 Ks and 0 Ls. But to each his own.

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#### Who_Cares

##### Active Member
I have decided to attempt to repair my LOC IV by cutting off and sanding down the remaining bits of fin and paint on the fin can. Then I'll surface mount some new plywood or fiberglass fins and do tip to tip. Before I attach the new fins I might just go ahead and sand the paint off of the entire airframe and wrap it with a couple layers of fiberglass for a bit of strength, but mainly for longevity.

#### beeblebrox

##### 8 C6-0, 12 D11-9, 20 D20-0, 20 E5-0, 3 Cinerocs
Glue the coupler into the fin can leaving at least a caliber sticking out. Inside the coupler put wood blocks to accept threaded inserts or T nuts, epoxy them if you'd like. You can use removable rivets (without the wood blocks) or self tapping screws, I just prefer machines screws with the inserts.
I slide the airframe onto the coupler, drill the holes, then remove the airframe so I can work inside the coupler.
Seriuosly, consider stepping up to 54. 38mm is good for getting your L2 but not for an honest to God L2 rocket. While there is a plethora of J motors, L2 goes beyond J, and how many Ks or Ls are in 38mm? The answer is 2 Ks and 0 Ls. But to each his own.
I believe in the kiss rule, 38mm is my choice for L2, kit ordered....
Will be a great rocket for H & I motors too... Just get certified, then go for broke! I see many people fail going too complex for a cert flight, keep altitude low, just make it work...

#### Who_Cares

##### Active Member
I believe in the kiss rule, 38mm is my choice for L2, kit ordered....View attachment 379290 Will be a great rocket for H & I motors too... Just get certified, then go for broke! I see many people fail going too complex for a cert flight, keep altitude low, just make it work...
I completely agree. I just want to get level 2 certified than enjoy myself at level 2 with a 54 or 75mm motor rocket.

#### DaveW6DPS

##### Well-Known Member
Oh whoops I forgot to mention I did attempt a level 2 cert with my LOC IV with an Aerotech J270W. The fins shredded towards the end of the burn...
I guess no one else is going to point this out, but I hate seeing things like this. Entering grumpy old man mode...

The LOC IV is designed for F through H motors. Putting a J motor in it with potentially four times the total impulse it was designed for, without extensive mods, is just not a good idea. It doesn't seem you learned anything from this experience. I hope whomever went through your level 2 checklist learned something--that they did a poor job "assisting" you to have a failure.

Stay with level 1 for a while, and work on learning how to do things right. Many of these mishaps happen to people who push the envelop before they are ready. When you do think about level 2, look at legitimate level 2 rockets instead of just "Put a J420 in your LOC IV and let er rip".
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