BT-70 Gemini Titan

Greetings,

I seem to recall a thread but cannot find it searching here on building the BT-70 clone of the Estes kit. It used clear acrylic rods attached to acrylic fins that extended from the lower end of the model. I think they were removable as well. Anyone know of this and where I might find it ?

TIA

Jim

Are you sure it was a GT? Sounds more like a Mercury Atlas. The GT has dual clustered motors, I don't see how that set-up can be incorporated into the model without burning the fins.

kuririn said:

Are you sure it was a GT? Sounds more like a Mercury Atlas. The GT has dual clustered motors, I don't see how that set-up can be incorporated into the model without burning the fins.

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Yes it was the GT, just don't know where I seen it. May not have been TRF....

zog139 said:

Greetings,

I seem to recall a thread but cannot find it searching here on building the BT-70 clone of the Estes kit. It used clear acrylic rods attached to acrylic fins that extended from the lower end of the model. I think they were removable as well. Anyone know of this and where I might find it ?

TIA

Jim

Click to expand...

Estes had you make a clear tube of flexible plastic, by wrapping it around the tube, then you glued the clear fins to that. If your going to be at NARAM I am planning on refurbishing the one that I built more then 40 years ago and flying it at NARAM

Here is OOP kit clone by PD Rocketry for a Gemini Titan based on a BT-70 body tube found on Rocket Reviews.

https://www.rocketreviews.com/pd-rocketry-gemini-titan-david-montgomery.html

Here is a TRF thread on the subject:

https://www.rocketryforum.com/threads/bt70-gemini-titan-or-mercury-redstone-plans.41738/

If you do a Google search on "BT-70 Gemini Titan", all kinds of stuff will come up.

Found what I was looking for. It was an article in Sport Rocketry and was actually BT-80

Jim

zog139 said:

Found what I was looking for. It was an article in Sport Rocketry and was actually BT-80

Jim

Click to expand...

Could you post the link to that article, or indicate what issue in which that appeared?

It was in the March/April 2017 issue of Sport Rocketry. The title of the article is "Gemini Titan II" by Thomas Beach.

I built a BT-70 version for NARAM. I ordered the capsule, interstage, and nozzles from Shapeways. I finished the model with a vinyl wrap from ACCUR8 models on ebay. The wrap is very nicely done and I highly recommend it. The wrap comes with basic instructions on building the model. I really like the fin setup which has you build an internal box along side the longeron and is very slick. I chose to not use engine hooks on mine and ejected a motor on both flights which is a DQ for the event.

Looks great, Jim. Wish I could have been there to see it close up. Sorry to hear about the ejected motors.

John
NAR #78048

ZOG139.. Tell me more about the internal box fin setup thingy on the GT?

When you buy the wrap, it gives basic instructions on how to build the model and the internal boxes to hold the fins. Basically you build a frame around the part of the clear fin that goes through the wall. After you cut the slot in the tube, you insert the fin through the wall into the frame and tack into place. Remove the fin and glue the frame in place. Dont want to give away too much detail. John Pursely designed this and the wrap, if you inquire with him about your interest, maybe he can send you as some pics

Thanks, I checked out Pursely web site and his GT wraps didn't mention anything about fins.
The Estes GT was my first clone project a long time ago, and the wrap around fin unit always broke and didn't look very good.

Here is another pic of my model that you can zoom in on to see the fins externally

grafgulch said:

Thanks, I checked out Pursely web site and his GT wraps didn't mention anything about fins.
The Estes GT was my first clone project a long time ago, and the wrap around fin unit always broke and didn't look very good.

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