2x Goblin Upscale

[rbeckey]

Here is a RockSim file for my winter project, a BT 80 based Goblin. Sandman made the NC for me, and it is a fantastic part. I am still trying to decide on 24 or 29mm MMT. Incidentally, I simulated the fins to scale, and they didn't look right. They look closer to the original in this sim. If someone has a minute and wants to look at the original Goblin fin compared to this one, that would be great.

The NC weight is measured and overridden in this simulation. It would be impractical to lighten it to any great degree.

I know this project has been done to death, but I just cloned the Goblin I wanted 30 years ago, and this seems like a great compliment to the clone.

 

[Elapid]

with a sandman nosecone, to boot!
i copied the fins exactly from the original... the ones in your sim look too skinny to me.

 

[sandman]

Not sure why...but I've made more upscale Goblin nose cones that anything else...

I never realized just how darn popular a very very simple 4FNC model could be.

Good Job, guys!

 

[Fore Check]

I've mentioned this somewhere before around here, but it seems to me that on some rockets - when they are upscaled - the fins "seem" to look too big. I noticed this very phenomenon on my pair of BT70 based upscaled Goblins. I faithfully upscaled the fin pattern to the same scale as the rest of the rocket.

Having said that, they look right when sitting next to a 1x scaled Goblin.

Here's my reference pic:

From left to right: Bt70 based 2 x 24mm D engine powered upscale, 2 x 24mm E engine powered DeucEE's Goblin, BT60 based 2 x 18mm powered Deuce's Goblin, and Goblin clone.


https://www.rocketryforum.com/attachment.php?postid=61811

 

[Micromeister]

Bob:
Your fins look correct to me.
I haven't done a BT-80 2X upscale I want directly to BT-101 I can't remember where I got the foam nose cone but it was about the right shape so I hollowed it out and made the thing a 5 D12 cluster. 36" homemade hemi chute, 1/4" balsa fins, epoxy rivited to the standard BT-101 body tube. NO internal stuffer tube added just the 3 inches taken up by the 5 D12 3/32" light ply and BT-50 motor tube centering rings and 1/4" elastic/Kevlar 6 foot shock cord. This model needed no additional nose weight. If I recall correctly the model Ewt is around 26ozs.

 

[gstarraider]

the nose cone used on the goblin was also used on the der red max. the long rounded tip on the cone was a estes cone they no longer sell in the pnc60 pack. everyone elses nose cone had a really pointed tit on the nose cone, just doesnt look right on the red max, goblin, ata sentinal, and the swat just to name a few.

 

[sandman]

the nose cone used on the goblin was also used on the der red max.

Well....sorta.

It's the same basic shape an ogive with a round tip.

The Der Red Max was a BT-60.

The Goblin was a BT-55.

You could easily make a BT-60 upscale Goblin with a PNC-60AH

The Goblin had a balsa nose cone BNC-55AO

The Der Red Max used a plastic cone.

 

[BobH48]

Originally posted by sandman
Not sure why...but I've made more upscale Goblin nose cones that anything else...

I don't know about anyone else, but I got 2 Goblins for free as Bonus Kits from Estes. I built the first one the day I got it. It was the first 'D' powered rocket I ever had.

There was something about the paint scheme and decals that was just so cool.

I have built a BT-5, BT-20, BT-50, BT-55, and BT-60 version and I have a BT-70 that is waiting for paint.

Interestingly, the only ones I ever lost were the original BT-55 size. I lost 2 of those but I still have one more kit left.


A lot of people feel the same way about Der Red Max.

I was out of rocketry when it was on the market so it doesn't have the same appeal as a Goblin but I did make one anyway.

 

[Micromeister]

I know just what your saying Bob: the Goblin was just the Bee's knee's back then... It's still one of my favorite models tho I've change the paint scheme to more suit a Halloween Orange/black theme since suffering a D13-7 Cato in my original I still fly all three Micro-Maxx 10.5mm, BT-55 kit and BT-101 Hobby Goblin
I thing I'll add a BT-80 version 4 D cluster using one of the slightly non-scale PNC-80 cones I have laying around just for fun.

Heres a look at that D13 cato aftermath