Newbie discovering Cesaroni

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

peeler5150

Herschel
Joined
Mar 17, 2022
Messages
19
Reaction score
5
Location
Salem, OR
#1 How do the engine casings mount in the rocket? Glued?
#2 I am creating a list of rocket engines comparing Estes, Aerotech and Cesaroni. So far it has been very educational but the final product may not be of much use to you experts. Estes and Aerotech are done. Cesaroni Pro24, 29 and 38 are done. Let me know if you are interested.
 
To #1, you might want to look at an assembly video. 24mm and 29mm have a an aluminum aft closure that screws into the case. 38mm has a plastic aft closure built into the reload that screws into the case.

Whoops, misunderstood. Don't glue the motor case in the rocket!
 
Last edited:
Most people mount the assembled CTI motors like you would with any other HPR motor. The rear ring on the motor pushes on the rocket motor mount tube during thrust. You just need something to stop it sliding backwards. Z-brackets, screws and washers on the aft end work. You can also get retainers from Aeropack to hold them in. This is generally a more expensive option.
 
You don’t glue the case into the rocket. The case is a reusable part that you reload, so it needs to be removable so that you can clean it, reload it, and use it in multiple rockets.

As @OverTheTop mentioned, you use a retainer to hold the motor in place. If you’ve only flown Estes black powder motors, then you might not know about thrust rings. Estes motors are a smooth cardboard tube that is the same diameter the full length of the motor. If you don’t install a motor block in the motor mount, the motor will just shoot through the rocket. But for composite motors, you don’t install a motor block, because the motors can be different lengths.

Instead of using motor blocks in the tube, the motor cases for composite motors generally have a thrust ring on the case when they are assembled. The thrust ring is at the nozzle end of the motor, and it’s a wider diameter than the rest of the case, and it can’t fit through the motor tube. So it keeps the motor from flying through the rocket.

Generally the rocket has a retainer that keeps the motor from falling out of the rocket. I like screw-on retainers. After you assemble the motor inside the case, you slide the case into the rocket so that the thrust ring is firm against the aft end of the motor mount tube. Then you screw the retainer on over the thrust ring to hold it in place.

If you are new to composite motors, I would suggest starting off with Aerotech single-use motors and hold off on getting started with reloads. If you already have rockets built for Estes 24mm D and E motors, you could try a single-use Aerotech E20. It will fit in the motor tube, even with the motor block installed, and it will work with an Estes clip retainer or Estes 24mm screw-on retainer. If you have rockets built for Estes 29mm E and F motors, you could try Aerotech F20, F23, F27, F42, F67, or G74 motors. All of these are fun motors, but be aware, your rocket will go higher than they would on an Estes motor.
 
You don’t glue the case into the rocket. The case is a reusable part that you reload, so it needs to be removable so that you can clean it, reload it, and use it in multiple rockets.

As @OverTheTop mentioned, you use a retainer to hold the motor in place. If you’ve only flown Estes black powder motors, then you might not know about thrust rings. Estes motors are a smooth cardboard tube that is the same diameter the full length of the motor. If you don’t install a motor block in the motor mount, the motor will just shoot through the rocket. But for composite motors, you don’t install a motor block, because the motors can be different lengths.

Instead of using motor blocks in the tube, the motor cases for composite motors generally have a thrust ring on the case when they are assembled. The thrust ring is at the nozzle end of the motor, and it’s a wider diameter than the rest of the case, and it can’t fit through the motor tube. So it keeps the motor from flying through the rocket.

Generally the rocket has a retainer that keeps the motor from falling out of the rocket. I like screw-on retainers. After you assemble the motor inside the case, you slide the case into the rocket so that the thrust ring is firm against the aft end of the motor mount tube. Then you screw the retainer on over the thrust ring to hold it in place.

If you are new to composite motors, I would suggest starting off with Aerotech single-use motors and hold off on getting started with reloads. If you already have rockets built for Estes 24mm D and E motors, you could try a single-use Aerotech E20. It will fit in the motor tube, even with the motor block installed, and it will work with an Estes clip retainer or Estes 24mm screw-on retainer. If you have rockets built for Estes 29mm E and F motors, you could try Aerotech F20, F23, F27, F42, F67, or G74 motors. All of these are fun motors, but be aware, your rocket will go higher than they would on an Estes motor.
Thanks, all.
 
#1 How do the engine casings mount in the rocket? Glued?
#2 I am creating a list of rocket engines comparing Estes, Aerotech and Cesaroni. So far it has been very educational but the final product may not be of much use to you experts. Estes and Aerotech are done. Cesaroni Pro24, 29 and 38 are done. Let me know if you are interested.

You can find a discussion of these topics here (and in some of the publications/links referenced in the primer):

https://www.mountainmanrockets.com/index.php/hpr-primer/
 
I have not found such a video. Lots of info on how to build the motors but nothing on how to put the engine in a rocket.
 
It just slides into the motor mount and then you engage whatever motor retention you're using (screw-on, z clips, snap ring, etc.).
 
VMax propellant was discontinued

....but there is still a stock of 'some' Vmax grains still at CTI. Two of my vendors have recently received shipments of F120 and G250 vmax 29mm motors that are clearly in the newer style packaging.

Admittedly, the dates stamped are 2015 or 2016.....so it's been explained to me that that is the date the GRAINS were made, not when motor was packaged. That's some serious deep stock!
 
Last edited:
....but there is still a stock of 'some' Vmax grains still at CTI. Two of my vendors have recently received shipments of F120 and G250 vmax 29mm motors that are clearly in the newer style packaging.
Who still has the G250 in stock? I would love to grab some if you don't mind sharing.
 
So is CTI making Vmax reloads again?
According to Banzai88, CTI still has stock left over from when they were manufactured.
....but there is still a stock of 'some' Vmax grains still at CTI. Two of my vendors have recently received shipments of F120 and G250 vmax 29mm motors that are clearly in the newer style packaging.
 
Back
Top