CTI Discussion Thread

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SolarYellow said:
So there should still be good distribution of Classic, Pink, Smoky Sam, Green/Green 3, and C-Star? Or is that affected by one of the shortages in a way I don't know enough to connect the dots?

Personally, I'd be perfectly happy to fly nothing but Classic, and our local guy has had an unfilled PO for many months. I haven't spoken at that level of granularity, but it's a reasonable assumption that he'd have ordered a bunch of Classic, since it offers great all-around performance and he hardly has any left.
Click to expand...

That's a whole 'nother step.
 
SolarYellow said:
So there should still be good distribution of Classic, Pink, Smoky Sam, Green/Green 3, and C-Star?
Click to expand...
If Red or Blue can't be produced, then Pink can't be either, since it's just a combination of Red and Blue grains, like Loki Cocktail.
 
The following propellants are currently unavailable due to supply issues: Classic, Mellow, Imax, White, Blue, Red
That might also include Pink, as @Neutronium95 mentioned.

There should be availability in White Thunder, Smokey Sam, Skidmark, Green.
Im not sure about C-star.

Vendors may have some old stock on-hand. For example, G250 Vmax motors are still available in Canada.
 
jsdemar said:
Answered here a month ago... no IMAX or Mellow Yellow. There's an alternate supply available for the missing ingredient, but it's from a different source and would require re-characterizing the propellant. With the higher priority work going on at CTI, they aren't willing to do that for the time being.
Click to expand...
Classic, Imax, Red, Blue, White are not available.
 
RocketTree said:
The following propellants are currently unavailable due to supply issues: Classic, Mellow, Imax, White, Blue, Red
That might also include Pink, as @Neutronium95 mentioned.

There should be availability in White Thunder, Smokey Sam, Skidmark, Green.
Im not sure about C-star.

Vendors may have some old stock on-hand. For example, G250 Vmax motors are still available in Canada.
Click to expand...
Cstar is available. Your list is correct.
 
Welp, the dreaded 54mm CTI aft closure burnthrough got me this weekend. K630, with burnthrough a fraction of a second after liftoff. That blew apart the lower airframe and destroyed the casing and threaded aft closure. In an exciting twist of fate, the event ejected the other motor (it was a 2-motor cluster), leaving the other spinning 50' in the air without an airframe. No damage to the other casing.
 
boatgeek said:
Welp, the dreaded 54mm CTI aft closure burnthrough got me this weekend. K630, with burnthrough a fraction of a second after liftoff. That blew apart the lower airframe and destroyed the casing and threaded aft closure. In an exciting twist of fate, the event ejected the other motor (it was a 2-motor cluster), leaving the other spinning 50' in the air without an airframe. No damage to the other casing.
Click to expand...
That bites. I wasn't aware that the aft closure was a problem too. Is there any way to mitigate this, sort of like people are trying to do with gluing the forward closure?

Sounds like the spectators got their money's worth at least!
 
DarthMuffin said:
That bites. I wasn't aware that the aft closure was a problem too. Is there any way to mitigate this, sort of like people are trying to do with gluing the forward closure?

Sounds like the spectators got their money's worth at least!
Click to expand...
It wasn't the only CATO this weekend......and a number of them were spectacular....
 
boatgeek said:
Welp, the dreaded 54mm CTI aft closure burnthrough got me this weekend. K630, with burnthrough a fraction of a second after liftoff. That blew apart the lower airframe and destroyed the casing and threaded aft closure. In an exciting twist of fate, the event ejected the other motor (it was a 2-motor cluster), leaving the other spinning 50' in the air without an airframe. No damage to the other casing.
Click to expand...
Same happened to me at Airfest Saturday. CTI K630BS aft closure failure at about 500 feet. Coasted to 1,000 feet rather than RocSim 6,500 feet. Took out the threaded aft closure, external section of tail cone, and bit of the end of motor mount tube. Second slap in the face when rocket landed in the trees right next to the food vendors at the North end of range. The motor mount was saved by the tail cone threaded metal motor retainer. Rocket can be salvaged, but different retention system will be required. Have asked my local vendor about replacement motor / case..........no replay so far. It was unexpected because I had a successful launch with same set-up 2 months ago.
Now have AT 1706 and 2800 54mm cases on order, with necessary hardware and case spacers. BYE CTI!
 
DarthMuffin said:
That bites. I wasn't aware that the aft closure was a problem too. Is there any way to mitigate this, sort of like people are trying to do with gluing the forward closure?

Sounds like the spectators got their money's worth at least!
Click to expand...
My understanding is that the unofficial solution is to grease the crap out of the casing prior to inserting the reload. I thought I did that, but when I took it apart, I saw that I didn't get great coverage on the other motor (in a 6G case with 2 spacers) that didn't CATO. I suspect that the very end of the motor got grease, but the rest didn't get pushed through.

It was spectacular and a lot less scary since it was at a reasonably far away pad. I really appreciated the LCO's (also launch director) speech before launch about how they really meant that this was a heads up flight and everyone should really get out and watch in case something goes horribly wrong. Honestly, I was kind of surprised not to be assigned to Padzilla for a little more distance to the crowd.
 
I have a Pro 38 6GXL, a pro 54 6GXL, and a Pro 75 6GXL cases. The pro 38 and 54 have the short spacer (xl) to adapt from the 6GXL to 6G reloads. In 75mm, I can only find a 1G and 0.7G spacers (for the goofy 5.3G case). What spacer do i need to use a Pro 75 6G load in a Pro 75 6GXL casing? Every vendor I've checked are totally sold out of the 6GXL loads, but some still have 6G loads available.

I'm really hoping CTI will be able to produce IMax again in the future. The M2245 is a sweet motor.

Thanks!
 
Had two issues with K940s the same day. The first flight was fine but afterwards, the case couldn't be removed - massive bulge near the where the forward closure meets the liner.
Second flight had a case burn through near the aft closure half a second into flight - cut through the case and the closure itself. Total loss of the airframe from the resulting fire.
Both the K940s were from the same production date, from the same vendor, bought and stored together.
So do we start epoxying both ends of the motors now? I'm afraid to fly my 54 reloads and my recently purchased 75 reloads all have liners that are too big (diameter) to fit into the cases.
 
Cameron Anderson said:
Had two issues with K940s the same day. The first flight was fine but afterwards, the case couldn't be removed - massive bulge near the where the forward closure meets the liner.
Second flight had a case burn through near the aft closure half a second into flight - cut through the case and the closure itself. Total loss of the airframe from the resulting fire.
Both the K940s were from the same production date, from the same vendor, bought and stored together.
So do we start epoxying both ends of the motors now? I'm afraid to fly my 54 reloads and my recently purchased 75 reloads all have liners that are too big (diameter) to fit into the cases.
Click to expand...
On the 54's, just give those to someone you don't particularly like. :headspinning:

On the 75 liners, cut down the OD with a palm sander and some 80 grit paper until they have a normal fit in the case. I would not be concerned about having to work those a bit. CTI 75 and 98 don't seem to have the same prevalence of issues as the 54's.

Good luck sir, sorry to hear about the failures, been there... https://www.rocketryforum.com/threa...-needs-built-first.167169/page-7#post-2204152
 
Cameron Anderson said:
Had two issues with K940s the same day. The first flight was fine but afterwards, the case couldn't be removed - massive bulge near the where the forward closure meets the liner.
Second flight had a case burn through near the aft closure half a second into flight - cut through the case and the closure itself. Total loss of the airframe from the resulting fire.
Both the K940s were from the same production date, from the same vendor, bought and stored together.
So do we start epoxying both ends of the motors now? I'm afraid to fly my 54 reloads and my recently purchased 75 reloads all have liners that are too big (diameter) to fit into the cases.
Click to expand...
Sorry to hear about your troubles. But hey! Bright side is that CTI has acknowledged (on this thread and others) 2, maybe 3 years back now that there is a significant issue with the 54 forward module sealing and they have no idea about the aft failures.

At one point, they were supposed to be setting up a new test cell and testing potential re-designs of the pieces, but all questions about it have been met with radio silence.

The link that rfjustin posted above is what most folks due in an attempt to mitigate the chances of a forward issue (and thanks again for the pictures). Sadly, nothing that folks have tried seems to mitigate chances of the aft failure mode.

But hey! Another bright side is that if you have a year to wait, you should get a warranty claim satisfied with no other issues......well, other than replacement cases and aft closures of new manufacturer potentially NOT being in any way cross compatible due to 'manufacturing tolerances'!

Fun Times! :(:(:(
 
Banzai88 said:
replacement cases and aft closures of new manufacturer potentially NOT being in any way cross compatible due to 'manufacturing tolerances'!
Click to expand...

Having formerly worked in manufacturing and been a key person getting my employer TS16949 certified, that excuse is a definite peeve*.

If the situation described occurs, there are only a few possibilities:

  1. The design is defective because it doesn't control tolerances adequately, including accounting for finish (and variation in finish) affecting fit.
  2. Old parts were not to spec and got shipped to the customer anyway.
  3. New parts are not to spec and got shipped to the customer anyway.
  4. Old and new parts were/are not to spec and got shipped to the customer anyway.
  5. The design has changed and they didn't provide any notice to the customer.
  6. The design includes an expectation that parts will be select-matched before shipping (in a quality environment, this must be written into process control documents, not just be "working" or "tribal" knowledge on the shop floor), but this is not communicated to the customer. Instead, the customer is led to believe that all parts should interchange. (Misleading the customer this way is not acceptable in a quality environment.)

There are no other ways it can land. All of the above are bull-carp.

This applies to the other manufacturer, as well.

I have Scots-Irish background, if you know that joke about them being "a bit peeved."
 
SolarYellow said:
Having formerly worked in manufacturing and been a key person getting my employer TS16949 certified, that excuse is a definite peeve*.

If the situation described occurs, there are only a few possibilities:

  1. The design is defective because it doesn't control tolerances adequately, including accounting for finish (and variation in finish) affecting fit.
  2. Old parts were not to spec and got shipped to the customer anyway.
  3. New parts are not to spec and got shipped to the customer anyway.
  4. Old and new parts were/are not to spec and got shipped to the customer anyway.
  5. The design has changed and they didn't provide any notice to the customer.
  6. The design includes an expectation that parts will be select-matched before shipping (in a quality environment, this must be written into process control documents, not just be "working" or "tribal" knowledge on the shop floor), but this is not communicated to the customer. Instead, the customer is led to believe that all parts should interchange. (Misleading the customer this way is not acceptable in a quality environment.)

There are no other ways it can land. All of the above are bull-carp.

This applies to the other manufacturer, as well.

I have Scots-Irish background, if you know that joke about them being "a bit peeved."
Click to expand...
You used a lot of words to say "$#1* Show". :)

Especially egregious since many of us have some of the competitors products that have been made by many different subcontractors and special runs across several decades.......and they all fit and function without question........so, it's entirely possible that the answer is "All of the above".
 
Banzai88 said:
You used a lot of words to say "$#1* Show". :)

Especially egregious since many of us have some of the competitors products that have been made by many different subcontractors and special runs across several decades.......and they all fit and function without question........so, it's entirely possible that the answer is "All of the above".
Click to expand...

I remember a quote from a Ford engineer when they bought Jaguar. After touring the factory, he said, "There's nothing wrong with their process that a good bulldozer wouldn't fix."

I don't think CTI or AT are close to that bad, fortunately.

But I'd sure like my local motor guy to start receiving his CTI POs.
 
SolarYellow said:
I remember a quote from a Ford engineer when they bought Jaguar. After touring the factory, he said, "There's nothing wrong with their process that a good bulldozer wouldn't fix."

I don't think CTI or AT are close to that bad, fortunately.

But I'd sure like my local motor guy to start receiving his CTI POs.
Click to expand...
My motor guy has been receiving CTI motors including my warranty replacement.
 
the avengers GIF
 
boatgeek said:
Honestly, I was kind of surprised not to be assigned to Padzilla for a little more distance to the crowd.
Click to expand...
Speaking as one of the RSOs at that event (but not for this rocket), please speak up if you have concerns about your flight and want more distance! When we have a line 10 folks long, it always helps us make faster and safer decisions when fliers shares their honest concerns up front and I don't think I've ever said "no" when folks want MORE distance.
 
robopup said:
Speaking as one of the RSOs at that event (but not for this rocket), please speak up if you have concerns about your flight and want more distance! When we have a line 10 folks long, it always helps us make faster and safer decisions when fliers shares their honest concerns up front and I don't think I've ever said "no" when folks want MORE distance.
Click to expand...
I would definitely have spoken up if I thought that I was too close, like if I had been assigned to one of the B pads. The A pads were far enough back that I wasn't uncomfortable, just a little surprised. Padzilla would have been a minor hassle to get the 1010 rail on too.
 
OzHybrid said:
Where can I find the specifications for all igniters supplied with CTI motors?
All Fire, Fire, No-Fire, max test current, resistance. Same safety data as MJG Technology supplies for their matches.
@Cesaroni Technology
@AeroTech Not just asking you.....
Click to expand...
As far as I know all CTI igniters are MJG firewire ematches. Some of their motors use dipped igniters, but those are still based off of the firewire.
 
Neutronium95 said:
As far as I know all CTI igniters are MJG firewire ematches. Some of their motors use dipped igniters, but those are still based off of the firewire.
Click to expand...

The dipped igniters don't have blue/white wires, or at least the last one I used didn't. The regular ematches are definitely firewires, which I think was confirmed by CTI in this thread.
 

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