Pershing 1A

[stantonjtroy]

My Christmas scratch build.
Based on a BT-80 with a paper transition (ala TLP). Fins are built up from 1/32" G10 glass sheet and balsa formers. Decals are a combo of Excelsior and my own. It's set up with a 24mm mount. I had originally planned to fly it on a composite E or F but as light as it is (don't ask, I havn't weighed it yet) I think I'll do first launch on a D12.

 

[Pem Tech]

Excellent work.
Do you have any other photos?

 

[rokitflite]

Layne... Your avatar is giving me nightmares.

 

[sandman]

Since I found the rocsim of the BT-60 version for somebody on YORF I may as well post the BT-80 version.

View attachment Pershing1Abt80.rkt

 

[Rocketcrab]

Since I found the rocsim of the BT-60 version for somebody on YORF I may as well post the BT-80 version.

Uh...that would be me. Thanks again! :santa-smile:

 

[stantonjtroy]

Excellent work.
Do you have any other photos?

Sorry, I don't. I had intended to shoot some build pics but it went together so fast I never got to it.

 

[stantonjtroy]

Since I found the rocsim of the BT-60 version for somebody on YORF I may as well post the BT-80 version.

Thanks. I'm always more comfortable with multiple sources for stability checks on scratch builds. I'd like to get this back (over power aside ) in one piece.

 

[Pem Tech]

Layne... Your avatar is giving me nightmares.

Thus is our nefarious plan to disturb the sleep of the entire world!!!!
BWHAHAHAHAHAHAHAHAHAAH

The best part is that this isn't even the animated GIF. The original that Brother John set us chomps its teeth. Talk about disturbing.
:eyepop:

*EDIT*

OK, now the chomping Llama is working.

 

[Fred22]

Thats an awesome avatar but i digress. Your pershing looks awesome
Cheers
fred

 

[Stymye]

like the Pershing !

I'm drawn to them because they are always an attention getter with the small fins and scale-like flights.

just too cool..! nice job

 

[Fred22]

Great photos of an awesome rocket. Pershings are great looking rockets
Cheers
fred

 

[powderburner]

Troy-

Nice looking P1a

Even if you didn't take pix during construction, could you take a few more now that it is finished? What did you use to build the base plates under the fins? How much nose ballast?

 

[Marlin523]

Neat looking rocket. By any chance, do you have a Rocksim file you would share with us?

 

[stantonjtroy]

I'll take a few more pics this weekend. I'm afraid I don't have a ROC SIM file as yet but am working on one. I'll post it as soon as I finish it. I'm not sure of the actual amount of weight in the nose. Sandman posted a ROCSIM profile based on a BT-80 with a CG at the base of the nosecone (without motor) so I just added shot to the nose until I had it in range. If I had to take a guess I'd say 1 to 1.5 oz. The base plates are balsa sheetscut to shape and sanded to contour on the body tube. Sealed and painted. Tube segments were made with thin paper strips.

 

[dedleytedley]

I built the TLP Pershing 1A and rocsimmed it to have a CP at the base of the second stage fins. Accordingly I set the CG one BT dia. ahead of it. The rocket flies fairly straight as built so I'm not sure if you need to set the CG so far forward. I posted my CP results on EMRR and I'm interested to see what numbers you derive. Ted

 

[terryg]

Rocket Team Vatsaas has a build thread on a large Pershing 1A.

https://www.vatsaas.org/rtv/arsenal/bradrocs/pershing/pershingdesign.aspx

I have the parts to build it, but I am using 7.5 flexible phenolic tubing rather then the QuikTube and it should be lighter because of this.
This is the rocksim file from their site.

View attachment Pershing54mm.RKT

 

[stantonjtroy]

This is the profile I used. Given it has the upper stage fins forward I like the Idea of a little more nose weight,it gives me 1.5 to 2 gague of stability. Even balanced as shown this thing is light.

 

[terryg]

I ran across this this rocksim file for a 2 stage small pershing. It would have to be modified since the upper stage uses an 10.5 mm apogee engine that I do not think is available.

View attachment scratch_mini_pershing.rkt

 

[stantonjtroy]

I ran across this this rocksim file for a 2 stage small pershing. It would have to be modified since the upper stage uses an 10.5 mm apogee engine that I do not think is available.

Too Cool! I might have to give this one a shot.

 

[1974_Trident]

...I think I'll do first launch on a D12.

I built a Pershing 1A about 30 years ago, an Estes Kit just over three feet tall. I would strongly advise against using the D12 engine, in fact if I had to do it over I would not use anything less than F.

Estes recommended the D12-3. A D12-5 ejected the chute about two seconds after the rocket lawn darted and split the body tube.

It would be a shame to see such a nice rocket as yours meet the same fate as did mine.

 

[Stymye]

the cg on my 4 " is just below base of the nosecone.

 

[stantonjtroy]

Well I managed to get it off the pad this past Saturday. I put it up on a D12-3. Initial boost was a little wobley but once it accelerated it went like a homesick angel. I think the woble was more due to fin size/low launch speed than general stability. I think next time I'll go with an E, Perhaps the new E20 (right Scott ). The only real downer of the flight was the recovery. Due to the cold weather (I suspect) the plastic chute tore on ejection. Sufice to say a quick recovery followed. Two fins popped off on landing but 20 seconds and a bottle of CA took care of that. In all not so bad a flight.

 

[sodmeister]

I built a Pershing 1A about 30 years ago, an Estes Kit just over three feet tall. I would strongly advise against using the D12 engine, in fact if I had to do it over I would not use anything less than F.

Estes recommended the D12-3. A D12-5 ejected the chute about two seconds after the rocket lawn darted and split the body tube.

It would be a shame to see such a nice rocket as yours meet the same fate as did mine.

Yes indeed ,a very sad day for me also as a young lad.My first lawn dart....and on a pershing no less.I don`t think I cried....but I sure was PI%%@off :jaw:

I since built a new one a couple years back using Alien Enterprises resin nosecone and fin set.I wonder if Mr.Miller still makes those ?

P

P

 

[sandman]

Yes indeed ,a very sad day for me also as a young lad.My first lawn dart....and on a pershing no less.I don`t think I cried....but I sure was PI%%@off :jaw:

I since built a new one a couple years back using Alien Enterprises resin nosecone and fin set.I wonder if Mr.Miller still makes those ?

P

P

I do but in balsa.

 

[sodmeister]

I do but in balsa.

Gordy ,is that for BT70 or 80 or 101 ?

Paul

 

[powderburner]

Gordy ,is that for BT70 or 80 or 101 ?

Paul

Yes.

He'll make any size you want.

I kinda think he would turn one for you at full size if you asked him.

 

[sandman]

Gordy ,is that for BT70 or 80 or 101 ?

Paul

The one on the picture was for a BT-101.

 

[sodmeister]

The one on the picture was for a BT-101.

Alright Gordy ,I`ll keep that in mind......after my Sidewinder project me thinks.

I know where this is going ------>> $$$$$$$$$$$

Paul

 

[sandman]

Alright Gordy ,I`ll keep that in mind......after my Sidewinder project me thinks.

I know where this is going ------>> $$$$$$$$$$$

Paul

I also make the decals for the Pershing 1a in BT-60, BT-70, BT-80, BT-100 (for the Launch Pad kit) and BT-101 for the old Estes Maxi Pershing.

Although orange for some dumb reason is a PIA for an Alps printer.

The reason the nose cones I make are three piece is so I can drill out the center section for nose weight (which you need!) and the bottom section is seperate so you can paint it olove drab and the top two sections white...no masking...I hate masking.

That makes the Pershing 1a one of the easiest scale models to finish.

If you use cardstock (100#) for the fins you can complete a Pershing 1a in about 2 hours and finish it the next day.

In the firts picture my BT-80 model is the one in the middle.