Strato Blaster build

Hello,

This is my first posting here on the forum. I recently acquired a Strato Blaster kit and have started building.

I’ve read the posting by mr_matt_II about his build several times.

First question I have is what engine/s would you recommend? Up till now I’ve only used Estes single use. To me it looks like the 32 mm engine has been discontinued so I was thinking maybe 29mm or 24mm. Have not seen many plugged engine. Can the ejection charge be left out or removed while loading the engines?

I would like to modify this glider to press 1000 ft at launch. I have already created a fiberglass mold of the fuselage and will be molding the fuselage soon.

Thanks for any advice.

Welcome to TRF!

While I can't answer any of your questions I'd very much like to see a build thread.

The 32mm casing and loads should still be available, you can always leave out the bp from the motor on a standard load, or use the 32 or 24mm rc casing and loads. 1000 feet in that wingspan is pretty small, depends on your eyes, that's a light plane for the 32mm loads but I've seen it flown on them strengthening might be required.

Frank

burkefj said:

1000 feet in that wingspan is pretty small, depends on your eyes

Click to expand...

Yes, I have been working on a prototype auto pilot. My idea is to send it up to altitude let it fly figure 8's around a gps coordinate then take control when I can actually see the rocket glider.

I have attached a photo of my prototype. It uses a raspberry pi, gps, and gyro. I have a included a level shiftier since I would like to run the servos at a higher voltage than I can measure on the pi. I can both control and locate the positions from the pie and control them via the radio. I've got everything logging to a database and have a friend who will going to tow the plane up while I collect data. I still need to calibrate the gyro and work on a smoothing algorithm (either Kalman or Complementary).

There are not that many new ideas out there any more. Has anyone tried this before?

Thanks,

KLB

I would be careful, with 32 mm motors, I blew the horizontal stab off of 2 of them and gave up. I did have many successful flights.

I believe in both cases, I gave too much elevator input during boost (dont ask me why I don't remember). Anyway, this took off the tail.

I would NOT mount the elevator servo the way I did. Although this makes the elevator linkage light and tight, I believe it lowers the resonant frequency of the whole horizontal stab. I don't think I fluttered the elevator but the whole stab.

I would still not do the elevator servo the way Estes does. I would probably put it on one of the booms maybe.

Couple of questions.

What motors did you have the best success with? It’s the most confusing area for me since I have only used single use motors. I picked up several plugged D-12’s but they are not going to go far.

I have looked at some of the re-loadable motors. I have only found one place that has listed 32 mm casings and reloads for sale. Have not called to see if they actually have them in stock.

I am planning for a 29 mm motor mount and an adapter for 24 mm. Not sure what would be best.

Elevator linkage. You seem very opposed to using the original version that runs through one of the tail booms. Is there a lot of slop in that method? I certainly would not want to cut a slot in the top skin but could it be routed through the wing instead with the exposed part glued to the non-moving rudder? Is there a better version of the original?

An alternative would be increase the boom width, mount the servo at the end and use some type of control arm possibly with a ball linkage plus add the same weight to the other side.

Strength. The weak parts of this model are where the boom connects to the wing, the rudder to the boom and rudder to elevator. Fiberglass is completely new to me. It took four tries to get a mold I am very happy with. Could these parts be glassed or at least epoxied to increase the strength? Where did the tail sheer?

Sorry to be a pest. Anyone chime in.

Thanks,

KLB

klb said:

There are not that many new ideas out there any more. Has anyone tried this before?

Click to expand...

Yes. https://nerdfever.com/last-flights-of-rocket-glider-autonomy/

The major problem here was not getting the GPS lock back after the boost.

I'm skeptical that the Stratoblaster has enough volume to hold the electronics you're planning. A larger airframe, at least to start, would seem like a better idea.

klb said:

Couple of questions.

What motors did you have the best success with? It’s the most confusing area for me since I have only used single use motors. I picked up several plugged D-12’s but they are not going to go far.

I have looked at some of the re-loadable motors. I have only found one place that has listed 32 mm casings and reloads for sale. Have not called to see if they actually have them in stock.

I am planning for a 29 mm motor mount and an adapter for 24 mm. Not sure what would be best.

Click to expand...

I used a 32mm mount, with reloadables made for RC. The all up mass was around 495 grams.

I would say the F-13RCT and the F-16J blackjack were the best all around. A D12 will certainly launch it enough for test flights so those are fine with an adapter. I used a couple

The G-12 was also fine but you need a lot of nerve. You need to let it go straight up. Any significant deviation from vertical will let it gain a LOT of speed. That is how I took the first tail off. After maybe 600 feet I let it level off under power. Mistake.

The G-12 burns for over 8 seconds. Count that off in real time and imagine that little plane heading straight up and away from you at maybe 100 mph for 8 seconds. It is flyable but very small that high up.

klb said:

Elevator linkage. You seem very opposed to using the original version that runs through one of the tail booms. Is there a lot of slop in that method? I certainly would not want to cut a slot in the top skin but could it be routed through the wing instead with the exposed part glued to the non-moving rudder? Is there a better version of the original?

An alternative would be increase the boom width, mount the servo at the end and use some type of control arm possibly with a ball linkage plus add the same weight to the other side.

Click to expand...

I did not like the slot in the wing at all and I did not like the nyrod "snake". My second idea is what you are saying, increase the boom width and put the servo there.

Now I am sure a lot of these flew with the stock elevator set up but I don't know how many flew under F or G power. Any way who I am to talk, I lost 2 of them!

I agree with the other poster, this is a small plane to mount that Arduino thingy in, I am sure something could be made to work but it would be much easier on something bigger. And a lot will depend on the quality of your GPS receiver, I have a turbine powered RC plane and I have telemetry that lets me look at 3 axis G force and the number of satellites locked at any given moment, under high "G" (10-14gs) you loose a lot of them.

And not all GPS receivers are made the same, you get what you pay for.