3" Semi-Scale Bullpup Build

qquake2k said:

One of the features of Open Rocket, is the ability to print the nose cone profile. As it turns out, the Estes cone is closer than I thought. I printed it on card stock, then used it as a guide as I slowly shaped the cone. As with cones I've turned before before, final shaping was done with 60 and 120 grit sandpaper. Then finally, I cut the tip off.

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I've done that before too! Usually I make a negative half pattern that follows the outside of the shoulder and ogive (it sits on top the cone being turned), if I can find one I will post a photo (may or may not be able to find them after the move a few months ago).

qquake2k said:

I chiseled the tip a bit, then went to sandpaper. I'm very, very happy with how this turned out! I still need to do final sanding with finer grits to get it paint ready. I got to thinking about it, and this is the first true ogive cone I've turned, and also the longest.

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Very nice work! Kudos for proper safety gear!

Glad to see you back! I'll be watching this. op:

Now, if anybody wants to collect some data for me about the Estes Bullpup 12D (lengths of the body tube, tail cone, launch lugs, as well as scans of the fins and decals (with rulers for scale), etc.) I might be talked into simming this one up. :wink:

Jim,that's a thing of beauty!Just like those pens you made for me.Nothing but the best!

With your skills your the right person to do a build thread.And everyone follows your step by step illustrations.I do remember telling you to turn your own nose cones a few years back.You are the one that got me into some power tools(drill press to make my centering rings,bandsaw for other projects).I wish I had just 1/4 of your skills.You had a great roll model in your father that taught you well and your just passing it along to all of us here on the forum who follow your build threads.Keep up the great work!

Even though I never met him,I agree and you know he's up there with a huge smile on his face saying to St.Peter,"That's my boy and I'm sure proud of the way he turned out!Always thinking of others before himself......":grin:Now on with the build my friend.......................................

Time to cut out the fins. I was planning on using 1/4" plywood from Michael's, but I dug out some 3/16" that I ordered several years ago. It wasn't nearly as warped as I remember. I cut out four "blanks" on the bandsaw. As I normally do, I "pinned" the blanks together with 1/4" dowels, so I could cut and sand them all together. I used the fence on the bandsaw to cut the tabs to keep them as uniform as possible.

I used the same method for the canard fins.

I also did some final sanding on the nose cone with 320 and 400 grit to get it paint ready. But with the storms we've been having here. I don't know when I'll be able to paint. With the faceplate off, I was able to get an actual weight on the nose cone. Open Rocket estimated 18.7 oz, so it's a bit lighter. That's a good looking nose cone, if I do say so myself.

I realized I had never weighed the tailcone. Open Rocket estimated 5.16 oz, so it's actually quite a bit lighter.

Wait one minute,why isn't that scale on your stove?Looks like the washer or dyer.Nose cone came out perfect.Great job putting a foil on the fins.

I went ahead and weighed the fins, too. OR estimated 4.29 oz on the main fins, and 0.352 oz on the canards.

cjp said:

Wait one minute,why isn't that scale on your stove?Looks like the washer or dyer.Nose cone came out perfect.Great job putting a foil on the fins.

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Ha! You remembered! I actually did take a photo on the stove, but decided the light was better in the garage.

This is great stuff!

Quack, a question.
When your cutting on the band saw, are running the upper band guides as high as shown in the picks?
Or are they closer to the stock?

Woody's Workshop said:

Quack, a question.
When your cutting on the band saw, are running the upper band guides as high as shown in the picks?
Or are they closer to the stock?

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No, I run them like in the pics. Why do you ask?

2 things, safety and blade drift.

qquake2k said:

Ha! You remembered! I actually did take a photo on the stove, but decided the light was better in the garage.

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You know you can't forget a stove as a workbench when you took those pictures in years past!!I don't remember much do to old age but some things are burned in my memory.lol

cjp said:

You know you can't forget a stove as a workbench when you took those pictures in years past!!I don't remember much do to old age but some things are burned in my memory.lol

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Yeah, and it used to irritate me when my son would cook on my workbench. LOL

I found a 1/4" plywood centering ring that I had obviously cut by hand on the bandsaw, but had never finished. I cut the second ring from 3/16" plywood with a 3-1/4" hole saw. As I've done before, I mounted them on the lathe and cut them to size with a chisel and a coarse file. Then cut the center holes with a 1-3/16" hole saw, and sanded them to fit with the Dremel.

I epoxied a block onto the forward centering ring to attach the forward rail button to. The rear rail button will screw into the tailcone shoulder, so a block isn't necessary on the aft centering ring.

Rocketry 101,simply the best!!!Glad your back Jim.Keep Joe away from your stove.Over cooked rocket parts can upset your stomach.uke:

cjp said:

Rocketry 101,simply the best!!!Glad your back Jim.Keep Joe away from your stove.Over cooked rocket parts can upset your stomach.uke:

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Not to mention the fire hazard!

Ohh man,,
How are you Jim...
It sure is nice to see you back...
I sure have missed your builds with all of the pics
of the correct way to machine a piece of wood,, lol...

It really is nice to see you back man..
I sure hope this is a positive indication of your health...
My prayers have been with you...

Teddy

hahahaha,,
I just saw your signature line....
I guess it's an ongoing battle,, lol...
That's ok cause you're going to do wonderful through it....

Teddy

So glad to see someone turning their own cones, I haven't turned one in a decade or so...

I need to get my own lathe... and somewhere to put it.

I've turned a few cones. I must say it is gratifying. I think I'm most proud of the 5.5" elliptical.