CTI Discussion Thread

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I'm not so sure I want to fly my J145..... Sounds like gluing the grains in might be the best solution for now.
 
Currently getting ready to assemble my first Pro-75 motor and have a few questions:

1) The instructions mention greasing the inside of the forward closure assembly and forward end of the smoke grain, but don't mention what type of grease to use. I have a tube of Lucas Oil White Lithium Grease on hand. Would that work? If not what should I use?

(Also, I also have a spray can of 3-In-One silicone lubricant. I'm thinking of spraying a thin coat of it into the metal case before inserting the liner to help with removing it post-flight. Is this a good idea?)

2) The instructions seem to be written for Gen 1 hardware, but I am using Gen 2. Am I correct in assuming that the guidelines for how much to tighten the rear closure and forward retaining ring are the same for both generations of hardware?

3) The reload kit came with a long thin cardboard tube that is not mentioned in the instructions as far as I can tell. My only guess is that one is supposed to run the igniter through it before inserting into the motor to help ensure it touches the top of the motor, but I wanted to check.
 
rocketgeek101 said:
3) The reload kit came with a long thin cardboard tube that is not mentioned in the instructions as far as I can tell. My only guess is that one is supposed to run the igniter through it before inserting into the motor to help ensure it touches the top of the motor, but I wanted to check.
Click to expand...
Yes
 
rocketgeek101 said:
Currently getting ready to assemble my first Pro-75 motor and have a few questions:

1) The instructions mention greasing the inside of the forward closure assembly and forward end of the smoke grain, but don't mention what type of grease to use. I have a tube of Lucas Oil White Lithium Grease on hand. Would that work? If not what should I use?

(Also, I also have a spray can of 3-In-One silicone lubricant. I'm thinking of spraying a thin coat of it into the metal case before inserting the liner to help with removing it post-flight. Is this a good idea?)

2) The instructions seem to be written for Gen 1 hardware, but I am using Gen 2. Am I correct in assuming that the guidelines for how much to tighten the rear closure and forward retaining ring are the same for both generations of hardware?

3) The reload kit came with a long thin cardboard tube that is not mentioned in the instructions as far as I can tell. My only guess is that one is supposed to run the igniter through it before inserting into the motor to help ensure it touches the top of the motor, but I wanted to check.
Click to expand...
You don't need to grease the smoke grain, the 75mm front closure is plugged. 99% of the people that I know use Super Lube for greasing the threads/o-rings, it's a silicone grease that's readily available from most hardware stores.

The Gen1/Gen2 instructions are really identical, the main thing is that the forward closure ring needs to be flush with the front of the case. Sometimes (if not usually...) the rear closure will not go in flush with the case once you tighten the front closure ring, it it's tight and there's less than 1/8" of gap then you got it correct. Just make sure that you clean the heck out of the threads on both the case and the closures afterwards... a stiff nylon brush is ideal for that since it won't scratch the case.
 
cerving said:
You don't need to grease the smoke grain, the 75mm front closure is plugged. 99% of the people that I know use Super Lube for greasing the threads/o-rings, it's a silicone grease that's readily available from most hardware stores.

The Gen1/Gen2 instructions are really identical, the main thing is that the forward closure ring needs to be flush with the front of the case. Sometimes (if not usually...) the rear closure will not go in flush with the case once you tighten the front closure ring, it it's tight and there's less than 1/8" of gap then you got it correct. Just make sure that you clean the heck out of the threads on both the case and the closures afterwards... a stiff nylon brush is ideal for that since it won't scratch the case.
Click to expand...
It dose help with after flight clean up if one greases sides and end of smoke grain that goes down into rear clouser.
 
Are the CTI igniters that come with the 54mm motors the same as e-matches we use for altimeter charges (9 volt)?
 
Plus, the CTI motors with the BP ignition pellet in them (all 24's, 29's, 38's, and most 54's) make excellent airstart motors... they tend to light easier than AT's. The lower current required for lighting them is a bonus.
 
JackC said:
Are the CTI igniters that come with the 54mm motors the same as e-matches we use for altimeter charges (9 volt)?
Click to expand...
With a handful of exceptions, yes. The exceptions (Imax? I forget) have pyrogen on them but I'm not sure if their current requirements are different.
 
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mikec said:
With a handful of exceptions, yes. The exceptions (Imax? I forget) have pyrogen on them but I'm not sure if their current requirements are different.
Click to expand...
Some of the other do too, and CTI has been known to change them for the same motor. For example I have burnt several J430 some have had a pellet in the fore grain lit with a match, some no pellet lit with a pyrogen encased ematch.
 
rocketgeek101 said:
Currently getting ready to assemble my first Pro-75 motor and have a few questions:

1) The instructions mention greasing the inside of the forward closure assembly and forward end of the smoke grain, but don't mention what type of grease to use. I have a tube of Lucas Oil White Lithium Grease on hand. Would that work? If not what should I use?

(Also, I also have a spray can of 3-In-One silicone lubricant. I'm thinking of spraying a thin coat of it into the metal case before inserting the liner to help with removing it post-flight. Is this a good idea?)

2) The instructions seem to be written for Gen 1 hardware, but I am using Gen 2. Am I correct in assuming that the guidelines for how much to tighten the rear closure and forward retaining ring are the same for both generations of hardware?

3) The reload kit came with a long thin cardboard tube that is not mentioned in the instructions as far as I can tell. My only guess is that one is supposed to run the igniter through it before inserting into the motor to help ensure it touches the top of the motor, but I wanted to check.
Click to expand...
Good guesses! Have you seen my assembly video for the CTI K1085 (75mm 2 grain)?
 
Are the 38mm I800 reloads still available? These make me giggle. 800 Newtons for half a second is a hoot!
 
Since the fire and the discontinuation of Vmax, the only re-stocking of Vmax loads I've seen in years are the 29mm F120, and even those have 2015 grain casting dates.

I agree with your enthusiasm for fast burns. With the 'other guy' discontinuing many slow selling loads, looks like most ultra fast burn loads are going away.
 
Sooner Boomer said:
Are the 38mm I800 reloads still available? These make me giggle. 800 Newtons for half a second is a hoot!
Click to expand...
I still have one in my launch box. It needs to take a ride in my Blackhawk 38. I just need a waiver to contain it.
 
Question on assembling the K300-P long burn:

The reload kit comes with a thick fiber washer that I have never encountered before in other CTI 54mm reloads. Where does it go?

Thanks,
Kevin.
 
kjm said:
Question on assembling the K300-P long burn:

The reload kit comes with a thick fiber washer that I have never encountered before in other CTI 54mm reloads. Where does it go?

Thanks,
Kevin.
Click to expand...
Before a seal disk in a AT motor the fiber washer was placed on top of top grain next to forward closure. Never see one on a CTI reload.
 
Are the delay formulations marked in a way that’s consumer identifiable?

I bought a 38mm G79 from another flyer, and the delay is trimmed shorter than I need. I have several other Pro38s on hand and would swap the delay if I could tell which were compatible.

@Cesaroni Technology
 
Question: I recently built the CTI M-840 yesterday, about 18 hours ago, the included adhesive is still very sticky, I am guessing this isn’t normal, is it supposed to be fully dry when hardened? The adhesive was mixed very very well on my part. Any suggestion would be greatly appreciated. In addition the adhesive was room temp, above the recommended 68 degrees F.
 
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Mightyrocketman said:
Wish I had knew about the 54mm 5G and 6G issues. Was on a 5G K600 white.
View attachment 537100
Click to expand...
Sorry this happened to you. This issue has kept me from buying CTI54mm loads for years.

Until they fix it WITHOUT the need to glue the forward closure (which still is not 100% a fix), I will continue to fly the other offerings.
 
My (2) H135 Pro29 motors performed flawlessly to get my Level 1 last weekend. Super easy for me to load it in the rocket even with my very low hand strength. I'll never use any other motors than CTI 🛐 :bravo:
 
hobie1dog said:
My (2) H135 Pro29 motors performed flawlessly to get my Level 1 last weekend. Super easy for me to load it in the rocket even with my very low hand strength. I'll never use any other motors than CTI 🛐 :bravo:
Click to expand...

Being part Canadien I thought the same and really supported the CTI product.. the bigger motors assemble more like an Aerotech however so as you get into bigger stuff, your feelings might change.

I’m frustrated beyond belief with the CTI 54mm collection.
 

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