Estes Mini Bertha

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Dudley,
The fin template is on the SP-TK3 pattern sheet with the plans linked to in post #2.
As Steve mentioned use the part #s from the parts list in the plans to get the parts from erockets.
For example the nose cone is part # BNC-20L. Go to erockets and scroll down the left hand menu to Parts for rockets/Nose cones/BNC-20. Scroll down the main field till you find the BNC-20L nose cone.
Do the same with the other parts.
Note: the 18mm Mini Bertha has a 13mm (BT-5) motor mount.
Just FYI.
 
Are the eRockets "Mini-Bertha" fins correct for the BT-5 or BT-20?
I bought them and they look much too small for the BT-20.
As to the fin template, I must be doing something wrong... when I print the page the template (again) seems much too small for a BT-20; like the image has been compressed or something. Than you for your patience with me. I'm about to hit the abort button on this project...
 
After doing more research, I think I understand my confusion... the plans I have are for an 18mm (BT-20) "Mini Bertha".
The BT-5 version a lot of guys seem to be building is a "downscale" version.
Correct. Many are downscaling to a BT-5 airframe for Micro Motors. The original kit is a BT-20 airframe w/ a BT-5 motor mount. As for the template print out..... look at your print settings and make sure the "Scaling" is set to 100% and not something like "Fit Page".
 
They should be around 1 x 3 roughly in size for the fins. The ones from erockets for the balsa SEM-FES-0803 are the correct fins as that is what I ordered for mine and they look correct.

The fin template on Jimz has a 1inch scale in the corners if you need a size reference.

Also use the PDF as that typically will have the scale correct

https://www.spacemodeling.org/jimz/estes/est0803.pdf
 
@Dudley I bought these when I built my clone.
https://www.erockets.biz/semroc-laser-cut-fins-mini-bertha-4-fins-1-16-balsa-sem-fes-0803/
And they have the nosecone too, which I also used.
https://www.erockets.biz/semroc-balsa-nose-cone-bt-20-1-4-elliptical-sem-bnc-20l/You can have both the main parts for less than $4.50 and shipping.

Where can one get the water slide decals though?
And before someone says print them, I don't have a color printer.
But I would gladly buy them, and some others to fill a full page, if someone wants to print them and mail them to me.
I would also pay to ship them.
 
Where can one get the water slide decals though?
And before someone says print them, I don't have a color printer.
But I would gladly buy them, and some others to fill a full page, if someone wants to print them and mail them to me.
I would also pay to ship them.
Tom Prestia, aka Tango Papa, has repro Mini Bertha decals.

https://www.tangopapadecals.com/prod03.htm
 
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