Ebay sled
This rocket is being built in memory of the J-eater that was lost.
It is
6in dia where the J eater was only 5.5in dia.
Also it has a 3in MMT
Target weight is 15lb.
This is a link to a PDF drawing of its design(14.3kB)
Summary:
This is a basic 3FNC design.
It will have two 6in phenolic tubes for the body, each with a single wrap of fiberglass.
I will put a wrap of Kevlar on the end to make them zipper resistant.
The 1/4in fins will have a layer of CF on each side with fiberglass going tip to tip across the MMT.
This fin unit will be inserted into the BT which will have slots cut on my table saw.
The MMT is a 2foot long piece of phenolic tube.
Fin shape is my
standard modified trapezoid
so they have good strength to weight ratio and security in landing damage.
Rail guides will be installed using blocks glued to the upper and lower CR.
I will use a 6in coupler that mates the two tubes together.
This will have a bulk plate made for each end out of 1/2in ply.
These will have a 1/4in step in them so they seal the tubes.
Each bulk plate will have a u-bolt for harness attachment.
There will be two 1/4in threaded rods running through each bulk plate to hold them to the bay.
I will glue tee nuts to the inside of the bay so the upper
BT can bolt in place.
Construction:
Because this was such a basic construction I only took a couple photos of the Ebay.
In this first photo you can see the logging accelerometer on the right and
the tiny PICO-AD4 on the left.
That altimeter is only 1in x 1/2in. It plugs
into the much larger harness board below it.
The sled in the bay is made from surplus circuit board material.
It is
simply attached to the threaded rod with zip ties.
Ebay sled
Here is a close up of the altimeters. Bit too much flash in this one. On the left you can see the push-on/push-off switch used for power.
Altimeters
Here you can see the access to the switch through one of the 3 vent holes.
ON/OFF switch
This is the bottom of the bay before I mounted the terminal blocks for charge attachment.
These CR's were made with my router out of 1/2in plywood. I routed a 1/4in notch around one side wo it slides 1/4in into the bay to seal it.
Ebay end
The bay has 3 tee nuts installed so I mount it with #8 screws to the forward section of BT.
Ebay installed