Re: Baby Bertha NC Pics on Binairies

Apologies as I posted this message on Binaries too....

I cut off the end of the shoulder making it 18mm in length. The moon shaped hole left at flat side is so I can add nose weight later on.....

The inside edge around the shoulder lip was scared in a criss-cross pattern and then the tube assy was epoxied in.

The plate is just a cap with vent holes to hold the altimeter in . It doesn't vent thru the shoulder sides but thru the sides of the housing tube, out thru the end cap and then out thru a larger payload bay below nose, which the nose assy is screwed into. Nose does not separate at ejection. Part of a larger payload assy.

This one isn't a deployment NC. Just an altimeter housing. Playing around testing some ideas for a future project.

I'll have some more pics of the finished rocket soon.

Your workmanship is sickeningly good :)

How did you cut the plates? CNC machine? :)

Outstanding craftsmanship.

Doug

Please Doug......are you trying to swell my boxhead even more??? :-) No fancy pants tooling here! A mini lathe and drill press are stuff of my dreams!!!

Any skills have been learnt the hard way....I just try to be neat & tidy..... God.....If only my mother heard that!!!

The following was used -

0.8mm Ply. A cordless drill & 3mm drill bit. Long 3mm bolt, 2 washers & a nut. 180 & 240 grit sand paper & cork sanding block. Scissors Hobby knife Steal ruler Trusty old pencil. Glue

A compass and protractor would have been real nice but I couldn't find my old school kit!!! Just measured everything instead and traced around Nose / Tubes for circles.....

With all my small rockets (Estes/Quest type things) I use 0.8mm ply for Fins, Bulkheads, C-Rings etc..... It cuts really easily with a good pair of scissors and for fins, just one slice from the hobby knife... :-)

I draw up the plan/template and then cut out the main ring etc. with scissors just slightly larger than is required (On the outside of the line). If I need a thicker ring or bulkhead I just cut the required number of plates and glue them together with wood glue. Use those paper clip clamp things from your newsagent to hold together, or squash under 2 sheets of thick glass with books on top. This Bertha NC uses 1.6mm plates......2 plates glued together...

Drill the 3mm hole in the centre, put the bolt thru with a washer on each side, put the nut on & tighten up. Put in the drill chuck & spin her up. Sand to size. Check fit regularly and take it easy!

For the centre hole, I VERY Slowly cut/traced around it with the hobby knife. Take your time here also, it can save frustration later on!!! A couple of passes around, pop out the centre and sand smooth to fit tube / MMT All other cuts & holes are made, hopefully, on their marks.

There's another 'Almost' finished NC pic on my caveman style website. :-) Has the moon shaped cap ready to be glued on after adding nose weight....