Im lookin at the Cesaroni pro98 case diagram. Does anybody have a picture of how the male threads mount into a rocket to screw the case onto? Is there a part Tim sells?
And what if you wanted to use a different length of case? For instance going from a 2 grain to 3 or 4 grain and back again. A guy may not want to always fly an big "M" to 20,000 all the time.
From the Cesaroni web site it show female threads on the forward end of the forward closure. I use a piece of all thread that screws into the forward closure and the passes through a plate and nut or eye-nut screws onto for motor retention. For the different length cases, just use a different length piece of all thread.
Doug
You do not necessarily need to change any parts. If you use a retention system on the aft end and then you just use the motor as an anchor for the shock cord so then all you need is an eye bolt and a jam nut that treads into the forward closure. I believe it is a 1/2" thread and 75mm is 3/8.
If using the forward closure as motor retention then you can use a piece of all-thread from the motor through a bulk plate and to a nut or eye-nut for your hard point for the shock cord as Doug does.
It can be done several ways, it just depends on what you are trying to accomplish.
From the Cesaroni web site it show female threads on the forward end of the forward closure. I use a piece of all thread that screws into the forward closure and the passes through a plate and nut or eye-nut screws onto for motor retention. For the different length cases, just use a different length piece of all thread.
Doug
Aye
Ill bet you can use that eye for a chute harness on the other side.
Should the plate be a steel plate sandwiched onto a plywood bulk head?
Or is an epoxied bulk head strong enough? Im tossing pictures around in my head, of possibly a light steel plate that bolts onto an epoxied centering ring with hidden nuts. That way you get still have front end access to the moter mount.
Tell me if Im way off in left field when the ball went right! 😉
It really depends on what you are trying to do. If you are using it for motor retention it will depend on the size of motor and the load it will carry. My O motor that Ron Z. flow in AZ this year was 2 .75 ply-wood if I am not mistaken. it really just needs to hold the weight of the motor and any other load it might see, including the G's in flight and deployment.
there are some that use the motor to hold the rocket together, motor thrust ring pulling up and the forward bulk plate pulling down. and held in place with motor and all-tread. then if you want to change from a 6in motor to 3 75mm motors you just need to change the bulk plate and thrust plate and install appropriate motors and all-thread. I have heard this called Texas style because it is a method use down there a lot it seems.