Build thread: 2.5" phenolic rocket

I have been posting quite a bit in the techniques section trying to learn about phenolic and I thought it would be appropriate to start a build thread. I don't have a finished rocksim file yet but as soon as I get one I'll post it.

This rocket will consist of a plastic 11.1" ogive cone, 2.5" phlexible phenolic, 6" electronics bay, and a 12" 38mm motor tube with 3 centering rings. It will be a 3 finned rocket.

View attachment 2.56 Phenolic rocket.rkt
Stay tuned...

I like this. Looks like it will go high.

Thanks. I have updated the image file and have edited the rocksim file a bit more. I can't export from rocksim at the moment as I am having technical difficulties with the program...can't print either.

I am not a fan of the flexible phenolic. Based on the research I have done, 'flexible' phenolic is just not-fully-cured normal phenolic, which, while less likely to crack on impact, does not have the raw strength that makes phenolic popular. I also worry about what's inside it, since uncured phenolic is formaldehyde...

Personally I wouldn't use phenolic as the airframe for the reasons given above. You might want to consider using Blue Tube or Magna Frame instead. Just a thought.

I have used all of the airframe sizes through 5.5", and 2.5 (2.6) is by far my favorite diameter airframe. nest would be 5.5. Love the design, as it reminds me of the Vaughn Brother Rocketry Javelin.

Here's an openrocket file of the design. I still need to adjust the centering ring positions.

View attachment 2.56 Phenolic rocket.ork

I regularly use and like 'glassed PML phenolic, one wrap of 6oz or 2 wraps of 3oz glass makes for a lovely stiff airframe that is both A) lighter than once-glassed Blue tube (I wouldn't fly blue tube naked because of water problems, ever) or FWFG, and B) durable enough for everyday handling dings, although not enough for risky (read; high wind -> bad landings) flights. I also greatly enjoy fiberglassing tubes, so that might have something to do with it.

I got a few photos to share. I got the motor mount pieces cut and the bulkheads for the AV bay almost done.

Here are the parts for my av bay. Completely scratch built...sorta...

So far I have the av bay about 90% done. I need to drill the holes to mount the altimeter and battery then a couple holes in the bulkheads for the ejection canister. Also the baro holes. I used SIG fast epoxy to hold the plywood to the tubes then secured it with USC 150 thick..

I also finished the fins. I was surprised at how easy it was to cut the 1/16" G10. My cheap metal jigsaw blade held up very well and still has a lot of life in it. I suppose though that if I were to cut some thicker G10 it would not have fared well. Anyway, I used some magnets out of an old hard drive to hold my template in place while I traced the pattern onto the sheet.

Next part of the project is to get the fin slots cut and finish the motor mount. I will also be building a 38mm to 29mm motor adapter.

I was able to get more done on this rocket. I have completed the motor mount. I'm working on a 29mm motor adapter but am thinking it will be better to just get one from aeropack. I built the fin can a bit heavier than I had planned on but the beefy internal fillets will provide the fin rigidity that I want. I also did a little more work on the av bay. I put a coupler stiffener in and also coated the alt. sled tubes with the thin epoxy to provide a little toughness to them...(just playing around really)...

Pics!

A very nice clean build. Keep up the great work!!

nice build.. keeping my eye on this

Thanks.

Here is my 38 to 29mm motor adapter. I decided on a length of 6" which is roughly half the length of the 29/360 motor.