Instructions needed for Estes Astron Farside catalog #K-12

[rdrown]

Looking to build an Estes Farside 3 stage rocket. I built several in the 70’s and would like to try it again. Never got any back. Would also need scans of fin diagrams. I am sure the fins were cut out using patterns.
Thanks for any help.

 

[gltruett]

https://www.spacemodeling.org/jimz/estes.htmYou can get the Rocksim file here: https://www.rocketreviews.com/estes-farside-x-4417.html

 

[rdrown]

https://www.spacemodeling.org/jimz/estes.htmYou can get the Rocksim file here: https://www.rocketreviews.com/estes-farside-x-4417.html

Sorry, that is the Farside-X. I’m looking for the Farside. The Farside has same size body tube whole length and fins are different. Thanks, though.

 

[gltruett]

The Farside is just above the Farside X in the first link. The fin patterns are included in the pdf.

 

[BEC]

The fins are the same for either variant. This is noted on the fin pattern sheet posted with both K-12 (https://www.spacemodeling.org/jimz/estes/k-12.pdf) and K-12X. The only difference from the top of the main body on down between them is the use of the launch lug standoff (or not) on the second stage. All the rest of the difference is which payload section is used.

 

[samb]

The Farside/Farsides X has identical specs for the fins and booster airframes. The difference is the payload section (Captain Obvious ). The question for today is how to get the stack moving off the launch rod with sufficient speed to avoid a cruise missile trajectory. The quick-hitting 18mm B3/B14 is long OOP. The C6-0 is not up to the task IMO. Maybe once in blue moon... on a dead calm day... with a 5 foot launch rod... maybe switch to a 3/16 rod or rail buttons... Maybe consider a 24mm C11 or D12 for the first stage. Good luck.

[edit] BEC for the steal!

 

[BEC]

Maybe consider a 24mm C11 or D12 for the first stage. Good luck.

This is the usual suggestion when the Farside/Farside-X come up on YORF.

I built a Farside as a Classic Model entry for a local contest some years ago and I think I have flown it with a B6-0 in the first stage….but I’ll need to go digging in my early flight logs to see if I did. Agree C6-0 is not really a good idea unless using at least a 4-foot 3/16ths rod.

Even in the instructions on Jim-Z a four-foot rod is suggested, though I can’t see how much good a 4-foot 1/8 inch rod would do over a 3-footer since even a 3-foot 1/8 inch rod is pretty flexible.

 

[rdrown]

Thank you @BEC and @samb for the info and link. I’ve been looking on Jimz’s website for hours and could not find anything. This is exactly what I wanted.

 

[rdrown]

This is the usual suggestion when the Farside/Farside-X come up on YORF.

I built a Farside as a Classic Model entry for a local contest some years ago and I think I have flown it with a B6-0 in the first stage….but I’ll need to go digging in my early flight logs to see if I did. Agree C6-0 is not really a good idea unless using at least a 4-foot 3/16ths rod.

Even in the instructions on Jim-Z a four-foot rod is suggested, though I can’t see how much good a 4-foot 1/8 inch rod would do over a 3-footer since even a 3-foot 1/8 inch rod is pretty flexible.

I have a six foot ¼ inch rod so I will probably put ¼ inch lugs on it.

 

[bjphoenix]

The question for today is how to get the stack moving off the launch rod with sufficient speed to avoid a cruise missile trajectory. The quick-hitting 18mm B3/B14 is long OOP. The C6-0 is not up to the task IMO. Maybe once in blue moon... on a dead calm day... with a 5 foot launch rod... maybe switch to a 3/16 rod or rail buttons... Maybe consider a 24mm C11 or D12 for the first stage.

I thought it unusual that the Estes recommended 1/4A, 1/2A or B3 for the first stage. I guess the idea is to take advantage of the initial thrust peak and then kick that stage.
I've never seen a full farside launched, a person would have to be pretty brave to launch one all up with big motors, especially with the small payload section. If you launch one with C11 or D12 first stage, that's basically minimum diameter.

 

[BEC]

When I built a Farside-X in my first rocketry period (~1967-1973) I am pretty sure I flew it, at least initially, 1/4A to 1/4A to 1/4A. IIRC, it staged the first time not far above the end of the standard 3-foot rod.

The design dates back to before there were Cs, and the B3 (later B14 when designations went metric) motors were 9 lbs. of thrust, peak, and the whole burn was 0.35s long.

 

[samb]

The motor selection in those vintage instructions is puzzling to me. Besides the obvious english units conversion 1/4A is still a low impulse motor. Unless 60s BP was a lot different from what we have now my thought is that the first 2 stages fired within the first 6 feet or so. That limited the weathercocking effect. 9 lbs of thrust in less than half a second. POW!

 

[BEC]

The motor selection in those vintage instructions is puzzling to me. Besides the obvious english units conversion 1/4A is still a low impulse motor. Unless 60s BP was a lot different from what we have now my thought is that the first 2 stages fired within the first 6 feet or so. That limited the weathercocking effect.

A 1/4A is a 1/4A....the fuel doesn't matter.

HOWEVER, the definitions of the impulse categories were different in the pre-metric days. The upper limit on each of the lower impulse classes was higher. Those old 1/4A.8s had a total impulse of 0.17 lb-sec, or 0.76 N-s, vs. 0.625 N-s max to be a 1/4A after the metric change. The only currently available 1/4A motor (1/4A3-3T) as a certified total impulse of 0.59 N-s.

I was looking at the old motors I still have from when I was a kid, and I still have a 1/4A.8-0 booster and two 1/4A.8-4 upper stages. Back then (1967) even the color codes of the motors was different than Estes' current practice. They were color coded by total impulse (with 1/4A being green, 1/2A being blue, A being purple and B being red) rather than red for boosters, green for single stage and purple for upper stage. That change happened at the same time as the move to metric designations.

9 lbs of thrust in less than half a second. POW!

Yeah, those motors were lots of fun to fly. I sure hope that Estes E impulse core-burner that we've heard about gets made and sold. A similar experience in a bigger package.

 

[caveduck]

Piston launching this out of a tower would be a good way to get a regular Farside up to speed. A decent floating-head piston will add 20-30% to the departure velocity. Of course that puts more complexity into the launcher than the rocket

 

[BEC]

Dave, that would be quite the interesting tower to deal with three sets of interleaved fins, and with the span of those on the first stage.

 

[dpower]

Estes has hinted that a C5-0S will be coming out, that should have sufficient thrust. That said, I’ve only flown my clone on a B14-0, 1/2A6-0, A8-5 combo. I built a Centuri T-Bird clone to use a 24mm booster (C11-0), which works a little better due to the ST-10 tube size.

 

[caveduck]

Dave, that would be quite the interesting tower to deal with three sets of interleaved fins, and with the span of those on the first stage.

My 2m competition tower would do it just fine. I can fly HPR MD models with up to a 12" span from it. I don't think the interleave is a problem, you can rotate them well enough to fit between the tower rails. A tower-in-a-can with no upper supports would also work fine. You could even fly it off a piston without a tower; that's done with egglofters all the time. All fun stuff to try!

 

[tomasinator]

The motor selection in those vintage instructions is puzzling to me. Besides the obvious english units conversion 1/4A is still a low impulse motor. Unless 60s BP was a lot different from what we have now my thought is that the first 2 stages fired within the first 6 feet or so. That limited the weathercocking effect. 9 lbs of thrust in less than half a second. POW!

View attachment 550596


View attachment 550597

When I was a kid, probably around 1970, I built a Farside. Being too impatient to take the rocket and launching supplies to the local elementary school's baseball field, I decided to launch the rocket from my front yard. Recovering the rocket was unlikely, because the neighborhood had been bulldozed out of the woods six years earlier. Other than front yards, it was all giant trees (oaks, walnut, maples). I used 1/2A6-0's for the booster stages and a 1/2A6-4 for the upper stage. When I launched it, the Farside barely cleared the launch rod before the booster blew off and simultaneously the second stage lit. It seemed like the rocket was only 12' high before the second stage finished and the main rocket took off. With 1/2A6's for all three stages, I did not lose the rocket. It did not go very high and it landed right in my front yard.