I have a question about the different Cherokee-D kits.....Kit K-47 has a balsa nose cone and a body tube length of 16.35". Kit 1247 has a plastic nose cone and a body tube length of 18". I have an extra Bull Pup NC to do the Cherokee with. Seems to me that the plastic nc would be longer than the balsa, so the 1247 kit would be maybe 2" longer from tip to bottom. Are the fins the same size in both kits? I can't find kit 1247 plans anywhere, the one on Jim Z's site take you to the K-47 plans.

Both sets of plans are on Jimz, the 1247 plans are at the bottom of the page.

Joe

Dave,

The leading edge is the one that is parallel to the grain. The root edge is the one whose corners are NOT rounded. I'm pretty sure that I measured correctly, but you may want to double-check. The PDF pattern that I attached to my post IS the correct size. Print it out and measure the entire area that shows grain. If it is 9" x 4", then you are on the money.

According to Craig McGraw's notes in the Expanded Estes Kit List (an excellent resource, by the way, worth adding to your bookmarks list), the original K-47 Cherokee-D used a shorter body tube (BT-55V) that was 16.35" long, and the model was barely stable at that length. It also had a balsa nose cone (BNC-55AC). Estes later updated the design by lengthening the body tube to 18" (a regular BT-55 length) and redesignated it as kit #1247 (this was in the Damon era). They also gave it a plastic nose cone (PNC-55AC). This later model was noted to have a much more stable flight.

The confusing thing is that the Estes catalogs from the era all list both versions of the Cherokee-D as being 21.6" long. I consulted Semroc's page of reproduction classic nose cones, and they list the BNC-55AC as being 5.375" long. Add that number to a body tube length of 16.35" and you get a total length of 21.725". Assuming that the plastic PNC-55AC was the same length as the balsa version, if you add 5.375" to 18", you get a total length of 23.375". It's odd that Estes never reported this updated length in any of the catalogs that featured the #1247 Cherokee-D.

By the way, some more excellent resources for cloning Estes kits are John Brohm's Estes Body Tube/Kit Reference v.3.1, his Estes Nose Cone Reference List v10.1, and his Estes Fin Can Reference v2.0, along with the compiled Estes Nose Cone Pictures contributed by Arley Davis. The Building Tips page at Ye Olde Rocket Shoppe contains a wealth of other information as well that is indispensable to us clone freaks. These PDFs are well worth downloading (I check them all the time) and YORS and the pages it links to all belong in every classic kit fan's or cloner's bookmarks list. They are on mine, and they are some my most used bookmarks.

Excellent resources for cloning information for Centuri kits are the Expanded Centuri Kit List at YORS, the Master Cross Reference List at Semroc's site, the Cloned Rockets Central site (I don't know who maintains it) and Doug Holverson's Centuri Memories page, to name just a few. (Jay Goemmer, don't you also have a page somewhere on Centuri stuff too? )

Hope this helps, and Happy Cloning from one repro freak to another!

Mark \\.

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SAM # 0011

Thanks GI, don't know why I didn't see that myself!

Oh shoot, I typed the wrong one. It was supposed to be root. And yeah, I do get 3.75. No biggie. My fingers and brain don't always get along.

Thanks for the other info, I did save the Nose Cone and Body Tube sheets for reference a little while ago. I am still finding info on this site that helps a great deal!

I measured the Fin Blanks from my Semroc fins and come out with these figures:

3 3/4" for the Root Edge
2 1/2" for the Leading Edge
2 7/32" for the Fin Tip
2 5/32" for the Trailing Edge

These measurements are taken as if the Fin Tip wasn't rounded off into the Leading Edge and the Trailing Edge.

Joe

Here's a heads-up: The latest revision of the XEKL is due in a few days. I'm finishing up some last-minute updates, and will be sending it to Scott shortly.

I have a clone of a short-body CD, but with the PNC-55AC. It has flown once on a C6-5 without showing any stability trouble. I have not tried it on a D12-5. I think RockSim indicated it was below margin at ignition, but may have been above margin by the time it cleared the rod (due to BP burn-off).



This wasn't the first time a kit length was found to be wrong. Centuri was worse. Most every catalog entry was rounded off. Estes did try to get reasonably close, but Centuri rounded up and down.

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
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SAM 0044
AMA 352635

If you look up the Cherokee-D in the old catalogs on the Ninfinger site you will see that they used the same picture every year. The Estes logo is the old one with a capsule orbiting the Estes name.

http://ninfinger.org/rockets/rockets.html

The decals on Jim Z's site are the newer logo.

Yeah, sloppiness in documentation like that is simply inexcusable...

(In case anyone is wondering, I'm a big FSI fan. )

Mark \\.

__________________
SAM # 0011

It is the same length, I checked my PNC-55AC earlier. Lots of good info in all the replies here. I didn't think to check that the Bullpup uses the same PNC-55AC as the later CD. I scrounged one out of the parts box, and sure enough, I've got one. I was trying to decide if I would cut down an 18" tube, and then saw this info on the later version using the 18" tube.

Oddly enough, when you load the #1247 plan, it has the K-47 plan pages shown, with the #1247 plans appended at the end.

I've had the decals for a couple years, so this has moved to the "build now" list. I never built one when they were in production. I'm testing out the production runs of my Fin Wizard to make absolutely sure all the body tube sizes are OK -- the prototype table was only a BT-50 model, so I've got a couple sizes yet to test.

I did make the fins out of basswood, and then decided to taper the fins. These are a pain, since you've got to sand everything but the root edge. No knife edge aggressive tapers on these, they are only gently rounded.

__________________
Lee Reep
NAR 55948

Projects: Semroc Saturn 1B, Ken Foss Designs Mini Satellite Interceptor
In the Paint Shop: Nothing! Too cold!
Launch-Ready: Farside-X, Maxi Honest John, Super Scamp