Estes K-3 Astron Space Plane Clone

[Austin]

Ever since NARAM 45, where my son first saw JimZ and Sandman fly their Space Planes, he has wanted to build one. For this reason, I bought some bodytube, BT20 as BT30 is hard to find, got some fresh balsa and printed the plans from JimZ's website. All the balsa was cut this past weekend and is ready for dry rubbing, sanding and shaping, then assembly. Unfortunately, I have a problem...

...no where in the instructions does it give you the length of the model's bodytube or nosecone. I am looking for the bodytube length, and nosecone length. I purchased a nosecone from BMS that isn't quite scale but I can sand it if needed.

Can anyone help me with the measurements? Also, can someone give me an idea of the noseweight required so I can get it close before trimming?

Thanks in advance,

Carl

 

[Micromeister]

Carl:
I have the BT-30 Lenth listed as 5.5" but I can find the nose cone... I'll look for it again this evening.
John

 

[seo]

According to Ninfinger the BT30C is 5.5".

See ninfinger

Scott

 

[seo]

BMS lists the BNC30E as:

0.767 OD 0.722 ID 2.190 Length

Scott

 

[powderburner]

JimZ has the plans at:
https://www.dars.org/jimz/estes/k-03.pdf
and in those plans, the BT is identified as BT-30C and the NC is identified as BNC-30E
Over on the body tube sizes page, JimZ confirms that the BT-30C is 5.5 inches long
If you check in one of the old Estes catalogs on the back pages, they list their BNC-30E as having an exposed length of 2 & 3/16 inches (pretty darn close to the 2.190 dimension that seo gave you)

 

[sandman]

Carl,

I was gonna help but...you seem to be under control now.

As for nose weight, I left the nose cone loose until I was finished trimming.

Oh, yeh, don't trim it until AFTER it's painted!

The little adjustment screws make trimming easy...well...sorta easy.

sandman

 

[powderburner]

Forgot to check the nose weight for you,
The Estes catalog says it weighs 0.12 ounces and is 11/16ths in diameter
No thickness dimension given in the catalog, but from what I remember these were only about 1/16th thick and had a small (1/16th?) hole through the center

While we are on the subject of old Estes designs, Carl, has your kid seen the old Flying Saucer? That one was lots of fun too! It was called the 'Invader' and the plans are at:
https://www.dars.org/jimz/k-19.htm

 

[Austin]

Guys...

Thanks much for such speedy replies...I knew someone had the answer...you all rock!!! Oh, and Powderburner...one clone at a time man... ...but the Flying Saucer will probably have to be done.

Thanks again to all...I will post some build pics when we get to building it, which should be soon.

Carl