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Zeus-cat
07-24-2007, 11:06 PM
I used the basic Tau Zero design by Jay Goemmer as the basis for my "Sheesh Kabob". It hasn't flown yet and I still need to check stability before it flies, but the build and painting is complete. I chose red and black to make it very visible in the air and on the ground. The stripes and the two Sheesh Kabob decals are homemade decals printed on my inkjet printer using Testor's decal paper. One of the "Sheesh Kabob" decals 'silvered' after application and I think that is due to a less than smooth finish at the time of decal application (read more for problems with the finish).

Body tubes, nose cone, engine hook, launch lug, and Kevlar shock cord are all from Semroc. The three inner "fins" are basswood and the three outer fins are balsa. the fin extensions are from the kitchen and are wooden skewers cut down and glued to the end of the fins.

I just weighed it and it comes in at 1.5 ounces empty.

I used the water-based airbrush paint (Createx) I found at Hobby Lobby recently. I thinned it by adding about 1 part water to 3 parts paint. The paint comes in plastic bottles with a flip top and the paint can be squeezed out a drop at a time (sweet!).

I was a bit disappointed in the red at first as it sprayed on and was completely flat. I mean flatter than most flat paints I have ever used. The black on the nose cone was the same. The red took four light coats to cover the white body tube evenly. The black took two coats to cover the balsa nose cone (one might have been enough). Cleanup was a breeze as I just kept spraying water through the airbrush until it came out clear.

I poked around and managed to find an old can of gloss overcoat in my hobby supplies. A few passes with that and the rocket looked like it does now. The red deepened in color and the shine really looks good. However, I can't recommend this method for high-performance rockets as the finish is NOT smooth to the touch. It is actually quite rough to the touch in many places, say 100 grit sandpaper rough. Not a problem for this bird, but for other rockets this could be a problem. Createx makes a gloss overcoat in this same series of paint and I may have to try that.

Zeus-cat

rocketguy101
07-25-2007, 12:37 PM
Nice! I like those stripes, always have since my son built an Estes Yellow Jacket (http://www.dars.org/jimz/est2008.htm). I created/printed a set off recently, but haven't used them.

Is your decal a single sheet w/ all the stipes printed on it, or did you go w/ individual bands? The reason I ask is I had problems trying make a big checkerboard pattern w/ DIY inkjet decals, and it stretched/distorted while trying to get it off the backing paper. I haven't used the Testor's paper--does it require a coat of decal film?

Zeus-cat
07-25-2007, 06:51 PM
Rocketguy101,

I used one sheet for all the stripes. The first sheet I tried was about one eighth of an inch to short and I had to pull it off the rocket and throw it away. The final sheet didn't want to line up as nicely as the first and I really fought with it. In the end I did stretch out one end of the sheet and cut the worst away with an X-acto knife. If I did it again I would do the four biggest stripes one at a time or in pairs. The smallest three stripes I would do as one sheet.

Since I used an inkjet printer, I had to spray the decal sheet with a clear top coat before putting it in water.

Tau Zero
08-13-2007, 12:27 AM
I used the basic Tau Zero design by Jay Goemmer as the basis for my "Sheesh Kabob". It hasn't flown yet and I still need to check stability before it flies, but the build and painting is complete.Zeus-cat,

I saw your post a few weeks back, :cool: but I've just been too busy to respond until now. :o

My standard "Tau Zero" design uses all balsa fins, and it *still* needs plenty of nose weight (namely, a Semroc SE-14 screw eye) to be stable on a "C" motor. Since you used basswood for the inner fins of your "Sheesh Kabob" design, I'd be even *more* concerned about stability. :eek:

I'd recommend that you order some SE-14's and some washer weights (there *were* listed as WW-7, I think) before you fire this one off.

I'd also suggest that you use a 12" parachute, since you have those cool dowels that (unfortunately) may be likely to break off on impact.


If you have any more questions or comments, please post them here!


Thanks, and cheers,

CPMcGraw
08-13-2007, 10:49 AM
Jay, just consider this the price for your new-found fame! You've been cloned and modified!

Zeus-cat
08-13-2007, 07:30 PM
Thanks for the advice, but I try to "scale" my motors to the rocket so that I don't lose sight of the rocket when I fly it. Therefore, I plan on flying my "Sheesh Kabob" primarily on A8-3 's. If I feel adventurous it may see an occasional B6-6.

If I do use a B engine I would most likely add some red carpenter's chalk inside the parachute for a way to spot the rocket at apogee. I can't imagine ever putting a C in this thing.

Those dowels aren't going to break off as they are attached to the fins very securely. I'll lose a fin before I lose a dowel.

Zeus-cat

Druid
08-13-2007, 08:57 PM
Very nice, I like the look of this one. Nice job, indeed!

A Fish Named Wallyum
08-13-2007, 09:18 PM
Jay, just consider this the price for your new-found fame! You've been cloned and modified!

If anyone out there is thinking of cloning and modifying me, I'd suggest a tad bit less Dicky-Do to bring my CP into alignment. :eek: