Shock Cord Mounting (LOC)

[Rick James]

Originally posted by Mad Rocketeer
Any further advice from anyone, based on my two sets of questions above? The more I know and the more opinion I've sifted through before I start gluing, the better.

Thanks.

I used the recommended mounting on my LOC Aura and while I was a little concerned as well, it works great. With this small diameter, I really didn't have maby other choices.

The LOC IV was my Level 1 cert rocket - it came with TTW fins, but I cut new through to the MT -- I basically did what you discussed, fillet inside and out. It flew fine. Second flight it hit the playa hard and loosened a fin a bit -- strengthened it with more epoxy and it's fine now.

I changed the shock cord mount on the LOC IV to an eye bolt on the rear CR -- I also added a third CR to help strengthen the fins. I used 12 feet of Kevlar instead of the supplied shock cord.

Hope this helps,
Rick

 

[rabidsheeep]

uhh, dont mine me asking but what is this type of attaching it? (i need a way to attach kevlar to a bt with a mmt in it already)

 

[powderburner]

Originally posted by lalligood
Otherwise, what would you/I do if the shock cord broke/burned/needed to be replaced?!?

If you originally attached to a CR and the inside of the fwd BT is clear, you can easily attach a new tether to a short piece of coupler. Slide it in the front of the BT (dry) and all the way back against the CR (use a dowel if your fingers or hands don't fit), then add glue/epoxy/CR/name-yer-own-poison.

 

[wickball]

Hi Guys, I am resurrecting this thread because I need some help. I have a LOC 4 (3.9" diameter rocket) that I built with the shock cord epoxied to the inside of the body tube, per the instructions. It has worked fine so far but I have built it up for dual deploy and it now weighs in at about 6 1/2 pounds loaded, ready to fly.
I am now becoming more nervous about the shock cord mount. I could use a few ideas on how I can retro fit an eye bolt, wall anchor, or similar fastener to the top centering ring. Anybody out there ever have to do this?
Thanks ahead for your advice.
wick

 

[cls]

howzabout this: instead of retrofitting the eyebolt to the top of the existing centering ring, get a 3.9" disk of 3/16" plywood and drill some holes in it, fit the eyebolt in the center, and glue it a small distance on top of the motor mount tube - voila, instant shock cord mount and bonus baffle plate for motor ejection.

 

[Chris TNR]

Originally Posted by cls

howzabout this: instead of retrofitting the eyebolt to the top of the existing centering ring, get a 3.9" disk of 3/16" plywood and drill some holes in it, fit the eyebolt in the center, and glue it a small distance on top of the motor mount tube - voila, instant shock cord mount and bonus baffle plate for motor ejection.

I have to agree with Cliff on this one. I have been using baffles for years now and I quite frankly haven't found a better way. My HP Rockets utilize this same method of baffle but are made from 1/8" & 1/4" Aluminum.

My rule of thumb is: If I can't (comfortably) fit my hand in the BT, a baffle will be built in! When it comes time to change out the shockcord, I use a socket with a long extension through the motor tube to loosen the nut on the eyebolt and out comes the shockcord. Getting it back in can seem a bit tricky at first, but I find a nice long piece of 3/4" dowell with the end slotted makes it much easier to get in, and hold, while a fellow rocketeer tightens the nut.
Some of my rockets use a 2" wide bridal strap (made of seatbelt nylon buought at the Hardware store) that extends just a few feet out the BT to help prevent zippering and although it's really strong when it's new, it's still just nylon and burns quicker than Kevlar, which means I have to change it out more often. The use of a baffle makes it, in this case, very convienient.

Why is it?....the bigger the hands, the smaller the body tube
____________________
Chris Emich
NAR #84102
TNRocketry
____________________
In the works...........
8" Dia. Upscale Bulldog L3 Cert. Rocket
Known as: Bulldragon

 

[jraice]

I used it on my first LOC kit, a graduater, and it worked fine... when my cousin got a LOC onyx I wanted to build it nicely for him, well the clay epoxy fillets were strong but didnt look amazing , but it looks pretty good and I used nylon accessory cord attached to the motor mount through a small hole in the forward ring, also, on my graduater I used 1/4" TN, not the supplied elastic...