CTI Discussion Thread

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I have had email correspondence with him recently...they are not in fire zone.
 
The Aerotech and CTI liners are the same size. However, standard tolerances are wide. I've attached the standard tolerances for Plenolic tubes. They are specified as 2.73" OD, 2.562" ID. My source tends toward the top of the tolerance. Still have to sand them sometimes.
 

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Hello.

Does the Aeropack PRO54 DELAY/EJECTION CLOSURE ADAPTER FOR CESARONI CASINGS fits, thread wise, to the Pro38 reloads? Sticking out is not a problem.

I guess it comes down to the inner diameter of the forward closure's ejection charge well.
 
Hello.

Does the Aeropack PRO54 DELAY/EJECTION CLOSURE ADAPTER FOR CESARONI CASINGS fits, thread wise, to the Pro38 reloads? Sticking out is not a problem.

I guess it comes down to the inner diameter of the forward closure's ejection charge well.

IIRC it does fit. I’ll check either today or tomorrow For you
 
Hello TRF community.
My name is Bob Pouliot. I have worked for Cesaroni Technologies since 2007 and am a BAR since 2000. After recently being promoted to management I've been snooping around the TRF and I'm glad to see that it's very popular and insightful. My hope is that CTI can provide an outlet for rocketeers who have questions, comments or concerns about our products.
I'm not a "Rocket Scientist" as some may think. I will leave that distinction to those who have earned it. I do have basic knowledge of how things work, and with my 20+ years of experience flying I'm sure I can be a valuable asset.
So if you have any questions, comments or concerns I'd love to hear them, or if you just want to chat feel free.
Is CTI ever going to make spacers for the 24mm reloads? You have 3 and 6 grain casings; why not sell these in a set with spacers like you do your other sizes?
Gordon Olson
TRA #2719
"It's always people who've never done anything that say that nothing can be done.' -Jesse DuPlantis
 
Is CTI ever going to make spacers for the 24mm reloads? You have 3 and 6 grain casings; why not sell these in a set with spacers like you do your other sizes?
Gordon Olson
TRA #2719
"It's always people who've never done anything that say that nothing can be done.' -Jesse DuPlantis
Yes we will likely make spacers for the 24mm cases as well, but no plans for the immediate future.

Bob.
 
Is CTI ever going to make spacers for the 24mm reloads?
CTI has said in the past that a spacer set to use a Pro24-1G reload in a 3G case would cost as much as a 1G case. At this small size spacers may not make much sense given the added weight. It might make more sense for larger cases, but I'm not sure what the market looks like for 4G or 5G reloads.
 
CTI has said in the past that a spacer set to use a Pro24-1G reload in a 3G case would cost as much as a 1G case. At this small size spacers may not make much sense given the added weight. It might make more sense for larger cases, but I'm not sure what the market looks like for 4G or 5G reloads.
It's not hard to make your own spacer
 
Thanks to the help of Robert Kieffer, the delay info has been scraped from pro38.com and ThrustCurve.org has been updated so that motors with adjustable delays list all the achievable delays (using the appropriate tool).
 
I purchased a Pro98-6xl set from a Vendor and I am very worried about some “pitting” on the case. I understand an extrusion process is used with the aluminum but two marks in question are very deep and may show cracking. I will be using N1560 & O3400 reloads with this case and it must be able to safely perform. Could I please get some feedback? Two photos are attached for reference. Thank you!
 

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I purchased a Pro98-6xl set from a Vendor and I am very worried about some “pitting” on the case. I understand an extrusion process is used with the aluminum but two marks in question are very deep and may show cracking. I will be using N1560 & O3400 reloads with this case and it must be able to safely perform. Could I please get some feedback? Two photos are attached for reference. Thank you!

I would get a replacement if it was my case. That's far to much money to be that sub par of a product.
 
I purchased a Pro98-6xl set from a Vendor and I am very worried about some “pitting” on the case. I understand an extrusion process is used with the aluminum but two marks in question are very deep and may show cracking. I will be using N1560 & O3400 reloads with this case and it must be able to safely perform. Could I please get some feedback? Two photos are attached for reference. Thank you!
Return the case to your vendor with a warranty form, we'll replace it for you.
 
Depends on your vendor. Mine does it right on the spot.

Then your vendor is doing it from their own personal stock, and awaiting a pay back from CTI. Most every one has said that, with rare exception, that's taking money out of their pocket and won't be doing it except on rare occasion.

I don't know who at CTI processes the warranty claims, and there are MORE than just a few posts about the year + warranty replacements, but any process that places the vendor in a position to take money out of their pocket to front for CTI, or leaves the customer hanging for an inordinate amount of time....but they need to review their process because it's broken.
 
I wanted to contribute my experience this summer to the discussion of issues with CTI forward closures. I have submitted this information to CTI through my vendor, but I’m hoping this post will be helpful to those trying to understand the issues and risks. I also want to encourage CTI to provide some insight on how to avoid these problems, or even better to make product fixes to address them.

My son and I have had three CTI 54 motor/case failures this summer out of 6 attempted flights, all at AeroPac launches in the Black Rock desert. In every case the failures occurred where the motor liner meets the forward closure. The first resulted in the rocket being destroyed. The other two were successful flights however the cases bulged and are no longer usable. I have heard CTI will replace products when they fail, however I’m hesitant to continue using their products when they fail at this rate. Details follow. If anyone has advice on what we should have done differently it would be appreciated.

Issue #1 CTI 5 Grain K650 Pink launched in a CTI 6 grain 54mm case with one CTI 54mm spacer. This was the second launch with this case, which was purchased in May 2020. The seal appears to have failed before motor burnout where the forward closure meets the liner, burning through the fiberglass lower rocket body and destroying our rocket (Wildman Punisher 3). This picture shows the pieces, including the top portion of the case, the spacer and the front closure.

Pict1-Punisher.JPG

Issue #2 CTI 4 Grain K630 Blue Streak launched in a CTI 5 grain 54mm case with one CTI 54mm spacer. This was the first launch with this case, which was purchased in July 2021. I added an extra O-ring to the forward closure and used WD-40 Silicone lubricant. The flight was successful however the case had a bulge near the front. The failure appears to be just below where the forward closure meets the liner. The liner is burned away however the O-rings on the forward closure appear intact.

Pic2-MM IMG_0864 6.49.26 PM.jpeg

Pic3-MM IMG_0889.jpeg

Issue #3 CTI 6 Grain K820 Blue Streak launched in a CTI 6XL 54mm case with one CTI 54mm XL spacer. This was the second launch with this case, which was purchased in July 2021. I epoxied the forward closure into the liner and added an extra O-ring to the forward closure. I also used WD-40 Silicone lubricant. The flight was successful however the case had a bulge near the front. The failure appears to be in the forward closure just above where the forward closure meets the liner. The first O-ring is burned through but the second (higher) one I added is intact. The liner does not appear burned.

Pic4-K820 IMG_0893.jpeg

Pic5-K820 IMG_0892.jpeg

Obviously all three of our failures involved spacers, but I have not ready any suggestion that creates failure risk. Again, and insights appreciated.
 

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I wanted to contribute my experience this summer to the discussion of issues with CTI forward closures. I have submitted this information to CTI through my vendor, but I’m hoping this post will be helpful to those trying to understand the issues and risks. I also want to encourage CTI to provide some insight on how to avoid these problems, or even better to make product fixes to address them.

My son and I have had three CTI 54 motor/case failures this summer out of 6 attempted flights, all at AeroPac launches in the Black Rock desert. In every case the failures occurred where the motor liner meets the forward closure. The first resulted in the rocket being destroyed. The other two were successful flights however the cases bulged and are no longer usable. I have heard CTI will replace products when they fail, however I’m hesitant to continue using their products when they fail at this rate. Details follow. If anyone has advice on what we should have done differently it would be appreciated.

Issue #1 CTI 5 Grain K650 Pink launched in a CTI 6 grain 54mm case with one CTI 54mm spacer. This was the second launch with this case, which was purchased in May 2020. The seal appears to have failed before motor burnout where the forward closure meets the liner, burning through the fiberglass lower rocket body and destroying our rocket (Wildman Punisher 3). This picture shows the pieces, including the top portion of the case, the spacer and the front closure.

View attachment 479265

Issue #2 CTI 4 Grain K630 Blue Streak launched in a CTI 5 grain 54mm case with one CTI 54mm spacer. This was the first launch with this case, which was purchased in July 2021. I added an extra O-ring to the forward closure and used WD-40 Silicone lubricant. The flight was successful however the case had a bulge near the front. The failure appears to be just below where the forward closure meets the liner. The liner is burned away however the O-rings on the forward closure appear intact.

View attachment 479261

View attachment 479262

Issue #3 CTI 6 Grain K820 Blue Streak launched in a CTI 6XL 54mm case with one CTI 54mm XL spacer. This was the second launch with this case, which was purchased in July 2021. I epoxied the forward closure into the liner and added an extra O-ring to the forward closure. I also used WD-40 Silicone lubricant. The flight was successful however the case had a bulge near the front. The failure appears to be in the forward closure just above where the forward closure meets the liner. The first O-ring is burned through but the second (higher) one I added is intact. The liner does not appear burned.

View attachment 479263

View attachment 479264

Obviously all three of our failures involved spacers, but I have not ready any suggestion that creates failure risk. Again, and insights appreciated.
That is sad as I have experienced both types of those failures with CTI 54mm motors and am leery about using my remaining CTI 54mm inventory.
 
Glad when I became a BAR I started with brand A (not much of a choice then) and never flew a brand C. Never had a CATO or case damage in 25 years. Somethings wrong somewhere now, when brand C came out never seemed to have the problems that are occurring now.
 
Could you confirm that flight #3 was the only one with the forward closure epoxied in? What kind of epoxy did you use on the closure(s)?
 
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