FlatCat Boost/Glider Build, Part 2 - PARTS IS PARTS!

For this build, I am going with the plans published in the August 1969 Model Rocketry Magazine article.

Copies of it can be found here:

http://www.ninfinger.org/rockets/ModelRocketry/Model_Rocketry_v01n10_08-69.pdf

 Just for grins, and a further source of reference, I have downloaded a copy of the MPC FlatCat kit instructions from Jimz:

http://www.spacemodeling.org/jimz/mpcr216.htm

I am deviating from the parts list outlined in the article, as all of the original pod components called out were MRI part numbers.
Instead, I am working with Estes components, since they are readily available, and will work just fine.
Here's a shot of most of this FlatCat materials kit:

·         Body Tube.  This is, of course, a 6 inch length of BT-20.
·        Nose Cone.  Pretty much any XNC-20 size nose cone would work, but I am going with the short plastic one in the current PNC-20 pack, since it is closest to the original.   I don’t know the exact part number, but I believe it is similar in dimension to the old BNC-20A.
A commercially made or turned balsa cone would also work here.  If this route is taken, don’t forget the:
·         Screw eye.
A major modification I am making on my model is the engine retention system.  As you can see, the original plans specify a standard spring steel engine hook, which would have to be attached to the exterior of the pod body tube.
My system will use the internal music wire hook outlined a few posts pack.  For this, my kit includes the following parts:
·         An engine block (AR-520 centering ring). If you want to totally scratch build, one can be made from a ¼” chunk cut from an expended 18mm motor casing. 
·         An engine retainer hook cut from a length of .020 music wire.   
·         Shock cord -  I will be sticking to the original plan with the length of cotton string for the nose/body tube attachment.  Mr. Stine went with this rather than a rubber or elastic cord to minimize nose cone snap back that could potentially tangle up with the glider at ejection and cause a ‘Red Baron’.
·         Launch Lug.   The article doesn’t specify a length, but 1½” -2” should be fine.
The glider parts are all cut from balsa stock available at any hobby store or the BORG (Home Depot).
If I can find it, I prefer to use C-grain balsa.  This is distinguishable by the presence of wood figure running perpendicular to the grain.  C-grain is harder and much more resistant to warping than regular straight grain wood.  This is highly desirable with glider wings, since any wing warps will result in a glider that is nearly impossible to trim for flight.
·         3/32” x 3” balsa for the wings.
·         1/16” balsa for the horizontal and vertical stabs.
·         1/32” x ½” plywood (optional).  I am substituting this for the side strips that hold the two sections of the fuselage together and form the sides for the ‘piece X’ slot.  This was done on my original FlatCats, as I found that balsa was not strong enough in this application to be durable through glide trimming and flight stresses.  Plywood will provide plenty of strength while adding only a negligible amount of weight.
·         ¼” x ½” x 20” balsa. This is for the glider fuselage sections and the pod pylon.  The most important point here is to select a perfectly straight piece.  
·         Silver trim Monokote or aluminized mylar adhesive film.  I use the Monokote.
·         Streamer material of your choice. 

This wraps things up for the parts ‘kit’.  The FlatCat is essentially an inherent scratch build.

Next post will begin the nitty-gritty process of glider construction.