Cherokee-D Question

[seo]

I justed printed out the instructions for a Cherokee-D from Jimz's site. I want to make sure that the fin templates printed out to the proper size. The root edge on the print out is 3 - 3/4". Does anyone know if is that the correct fin size?


TIA

Scott

 

[Larry]

I measured off mine built many moons ago and get 3-3/8"
From the root along leading edge I get 2-1/2" and bottom from root to tip 2-1/8" Close..............Larry

 

[seo]

Thanks Larry.

Those measurements are pretty close to the template I have.

Scott

 

[powderburner]

seo,

I checked the data on JimZ's site and came up with the same measurement you had for the root chord (3 3/4 inch). I also came pretty close to the same leading-edge and trailing-edge lengths that Larry gave. So who's right? Who knows

JimZ is usually pretty good about posting fin templates that will be accurate when printed at 100% (or else what's the point?). However, there is always the chance for a bit of distortion to creep in, during the scan (to create the template image), during the printout (of the image onto paper), and of course during my measuring with a ruler and a very old eyeball. Usually these distortions will only amount to one or two percent (except for the eyeball part), if even that much.

There is also the chance that Estes changed the kit during the production run and Larry's fin really does have a 3 3/8 inch root chord.

Anyway, I have attached a file that lists the key measurements of the Cherokee D fin, at least as I measured them from JimZ. FWIW

 

[seo]

Thanks Powder-

I found the same thing as you. My template matched Larry's measurements for the leading and trailing edge also.

Also, when I measured the width of the balsa sheet on the template image, it came out to 4" exactly, which leads me to believe that the printout is scaled properly.

Thanks for your help

Scott

 

[powderburner]

We'll make an analyst out of you yet.

 

[flying_silverad]

If you assume that the pattern that is available is correct, then you can assume that the balsa sheet pattern is 4 inchs wide. The balsa sheet, BF-47 was noted as being 3/32 X 4 X 9. This is the same part number as "32220" which lists the same sheet size.
Having said this, you can scale the root size accordingly.

When I print the "JimZ" pattern out, the background balsa sheet measures at 4.0" and the respective fin root is 3.75"

At least for this particular pattern, 3.75 is correct.

 

[astronboy]

Didn't the BT length change in this kit over the years?

 

[flying_silverad]

Originally posted by astronboy
Didn't the BT length change in this kit over the years?

As a matter of fact there were 2. The first tube was designated BT-55V which was 16.35". The second version used the designator BT-55 or 30382 which was 18".

I like to split it down the middle...17 sounds good to me!

 

[Zippy]

One thing to watch for is the resolution of the program your using to view/print patterns with. Cheesy Windows Paint for example will use 102 x 108 for new or pasted images. That will distort the actuall measurements. No matter what program you use allways check the images attributes or properties to be sure width = height in resolution. The images actuall width and height in pixels or any other measure don't actually have to match of course, just in resolution. Of course you also have to presume the image was scanned correctly to begin with.

zip

 

[astronboy]

Did the BT length change at the time that the plastic nosecone was substituted for the balsa one?

 

[flying_silverad]

Originally posted by astronboy
Did the BT length change at the time that the plastic nosecone was substituted for the balsa one?

Yes, it appears so.

 

[seo]

Originally posted by powderburner
We'll make an analyst out of you yet.

Chemical engineer by education, we tend to rely on empirical equations and close enough measurements ( i.e., we measure by buckets )

Scott

 

[seo]

Originally posted by flying_silverad
If you assume that the pattern that is available is correct, then you can assume that the balsa sheet pattern is 4 inchs wide. The balsa sheet, BF-47 was noted as being 3/32 X 4 X 9. This is the same part number as "32220" which lists the same sheet size.
Having said this, you can scale the root size accordingly.

When I print the "JimZ" pattern out, the background balsa sheet measures at 4.0" and the respective fin root is 3.75"

At least for this particular pattern, 3.75 is correct.

Yeah, that's what I figured. Thanks for the help.

 

[seo]

Originally posted by flying_silverad
As a matter of fact there were 2. The first tube was designated BT-55V which was 16.35". The second version used the designator BT-55 or 30382 which was 18".

I like to split it down the middle...17 sounds good to me!

I was wondering about that, the Rocksim files have the BT at 18". I was going to use 16.35 as the BT-55V designator indicated. But if both are correct, the 18" would be a bit more stable...

Scott

 

[seo]

Fliying Silverado-

Who do you think I should get my decals from, Jimz Or Tango Papa?

 

[powderburner]

Originally posted by seo
Chemical engineer by education, we tend to rely on empirical equations and close enough measurements ( i.e., we measure by buckets )

Scott

Aerospace engineer by education, we definitely rely on parametric equations in advanced programs to weigh airplanes that don't exist (and yes, I have been accused of measuring by buckets)

 

[flying_silverad]

Originally posted by seo
Fliying Silverado-

Who do you think I should get my decals from, Jimz Or Tango Papa?

I really don't have an answer for this. I think they are both good vendors in their own right. I have never actually used JimZ.
Though Tango Papa was the first to respond to my request for my upscale cherokee d decals.

I think someone else could probably answer this better.
John

 

[astronboy]

In my experience, Jim Z is typically cheaper than Tango Papa, but TP is much quicker to ship. TP also has more variety available than Jim Z

My advice:

If you need the decals within the next week or two, go with Tango Papa.

If you are ordering several different sets of decals for your winter projects, then order from Jim Z.

Remember: Free advice is worth just what you pay for it!!

 

[K'Tesh]

I justed printed out the instructions for a Cherokee-D from Jimz's site. I want to make sure that the fin templates printed out to the proper size. The root edge on the print out is 3 - 3/4". Does anyone know if is that the correct fin size?


TIA

Scott

Seems like this post needs a new reply...

Instructions and Fin Pattern for the Pre-Damon era logo Astron Cherokee D (K-47)(Short version) with two-piece fins.*


Source: Estes
Decals were not included with the instructions
Note: there's a dowel that acts as a standoff for the launch lug. Perhaps to be used with the short-lived 'C' Rail that Estes that was being sold at the time this was released.


Source: David Stribling


Instructions for the early Damon era Astron Cherokee D (K-47)(Short version) with one-piece, die-cut fins.



Source: JimZ's site

Note the short body tube (BT-55V (16.35")), the old logo on the decals, but the new logo on the parachute and the instructions.

The fin templates from JimZ's site don't have dimensions. JimZ's decals are not original scans.


Instructions, fin templates, and decals for the Damon era Cherokee D (K-47/#1247)



Fins were measured with a micrometer at .0935" thick.

Source: K'Tesh

There's always the possibility of other variants out there, if you find one, please share it. I'm also looking for pre-Damon era (Astron) Cherokee-D (K-47) decals (with a ruler for scale).

*The Cherokee-D first appeared in the 1970 catalog. Estes was purchased by Damon in 1969. However, the new logo was not in use when the kit was released (and funny enough, the catalog never did have it with the new Damon era logo).

More about the Cherokee D can be found here.

 

[rharshberger]

K'tesh, I think you just took the award for the oldest thread resurrection yet 17 years...

 

[o1d_dude]

Yep. We have a new record and a new champion of thread necromancy.

But it needed to be done.

I remember this thread from back in the days when it was only 4 years old.

 

[K'Tesh]

Made you look!!!