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Cesaroni Technologies said:
Not for the foreseeable future. I think we still have some Pro24 & 29 VMax available
Click to expand...

That's a shame. the small ultra fast motors were a real differentiator for CTI. The whole easy assemble thing is not an issue for me so I have no real reason beyond the 24mm long case to consider small CTI motors.
 
Posting for a friend.....These nozzles are from CTI M840 motors flown on 2 different rockets. One flown at XPRS last September 2019 and one this June at Mudroc. Each flight flew several thousand feet below the expected sims. Both nozzles have way more erosion then other 75mm long burn motors we've seen in the past.



CTI noz.jpg

Your thoughts.....

Tony Alcocer
 
Cesaroni Technologies said:
Oh now I get it... (takes me a while sometimes) you just want the knurling gone. I think we have a 54mm boat tail... without knurling.
Click to expand...
I've gone thru a number of those boat tails. With many of the 6XL loads I fly, they take a pretty good beating. They are just a bit too long and the aluminum actually is eroded during the burn. There was a thread on here several years ago with a number of photos.


Tony
 
tfish said:
Posting for a friend.....These nozzles are from CTI M840 motors flown on 2 different rockets. One flown at XPRS last September 2019 and one this June at Mudroc. Each flight flew several thousand feet below the expected sims. Both nozzles have way more erosion then other 75mm long burn motors we've seen in the past.



View attachment 434875

Your thoughts.....

Tony Alcocer
Click to expand...
Yes I've already seen them, we're trying to figure out what happened.
 
phyzzld said:
Hi Bob, welcome to the forum!

I was told awhile back that CTI does not make a boat tail for the 98mm gen 2 case. Are there any plans to make one?

Jeff
Click to expand...
We do sell one, ask your dealer. You'll need the adapter ring as well.
It turns out we have the hardware for P98 Gen 2 boat tail but it hasn't been certified yet. The P98 Gen 1 and the P75 Gen 1 and 2 boat tails are certified.
 
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For many of the longer Pro54 motors (e.g., L1030), it's a pretty common experience to have a small blow-by at the forward closure bubble the case. This has happened so often that many people have taken to gluing the forward closure into the liner in hopes of sealing it better. Is CTI aware of this issue and if so, are there plans to correct it?
 
mikec said:
For many of the longer Pro54 motors (e.g., L1030), it's a pretty common experience to have a small blow-by at the forward closure bubble the case. This has happened so often that many people have taken to gluing the forward closure into the liner in hopes of sealing it better. Is CTI aware of this issue and if so, are there plans to correct it?
Click to expand...
I fly a lot of the long 54mm CTI motors - the L265 and L935 in particular. I've been glueing in the forward closure for a while now. But at Airfest two members of our group suffered from the blow-by experience, but it was anything but small. In both cases it resulted in destruction of the fin can. It's serious enough that they both decided to quite flying those long motors. It would be nice to know if this is officially 'on the radar' for improvement.


Tony
 
mikec said:
For many of the longer Pro54 motors (e.g., L1030), it's a pretty common experience to have a small blow-by at the forward closure bubble the case. This has happened so often that many people have taken to gluing the forward closure into the liner in hopes of sealing it better. Is CTI aware of this issue and if so, are there plans to correct it?
Click to expand...

As a guy that's had his last 2 CTI 38s do that very thing....and is about to step into CTI 54s.....what glue is everyone using? Do folks scuff the inner liner as well?
 
Banzai88 said:
As a guy that's had his last 2 CTI 38s do that very thing....and is about to step into CTI 54s.....what glue is everyone using? Do folks scuff the inner liner as well?
Click to expand...
I've always used JB but others have used a variety of epoxies. The way it was explained to me, the goal isn't really to glue the grain in, but to make a seal at the top of the liner and the closure. I think some closures have two o-rings and others have just one. It's an unfortunate situation for otherwise fantastic motors.


Tony

here's a thread that has some detail:
https://www.rocketryforum.com/threads/small-bulge-in-rocket-motor-casing.144046/
(edited to reflect epoxy choices and to replace thread with a more relevant version)
 
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Bob mentioned up thread that theyre investigating the fwd closure issue.

I use the Jim Jarvis method of 30min epoxy on the forward closure lip of long 54s. Haven't done anything to 54mm nozzle lips or 38s
 
manixFan said:
I think most use JB Weld or something similar. (I've always used JB). The way it was explained to me, the goal isn't really to glue the grain in, but to make a seal at the top of the liner and the closure. I think some closures have two o-rings and others have just one. It's an unfortunate situation for other otherwise fantastic motors.


Tony
Click to expand...
JB Weld. Interesting. Some threads that I looked at just now in search also said 5 min epoxy would work well enough in the field.....seems to mostly be a 54mm thing?

A quick search just now showed threads all the way back to 2016 with this being an issue, SEPERATE from the fwd-closure-wrong-plastic issue.
 
Nytrunner said:
Correction, Baamram mentioned this in a previous thread
Click to expand...
Yes, I've been following this thread closely and there was no prior mention of the 54mm forward closure blow-by issue in this thread. Is Bamraam affiliated with CTI? If so, that's good to know.


Tony
 
Banzai88 said:
As a guy that's had his last 2 CTI 38s do that very thing....and is about to step into CTI 54s.....what glue is everyone using? Do folks scuff the inner liner as well?
Click to expand...
I normally use West Systems 105/206. If I am disorganised (rarely) BSI 30 minute epoxy is used.

I glue all 54mm loads like that now.
 
Bob, welcome to the forum. I fly a lot of CTI motors, and it's good to have someone here on the forum intersted in feedback.

I fly lots of 38, 54,75 and 98mm motors. Within that size range, the single biggest issue that I see is the forward closure burn-through. When it happens, the rocket is destroyed. I was discussing this with Jeroen at the time of the accident, so there was obviously no follow up, but it sure would be nice to solve this now.

Jim
 
mikec said:
For many of the longer Pro54 motors (e.g., L1030), it's a pretty common experience to have a small blow-by at the forward closure bubble the case. This has happened so often that many people have taken to gluing the forward closure into the liner in hopes of sealing it better. Is CTI aware of this issue and if so, are there plans to correct it?
Click to expand...
Yes we are certainly aware of the issue, I've been testing them for the last few weeks. Although I've yet to have a burnthrough or even a bulge , it's been plain to see that the gasses aren't flowing evenly around the forward closure as we would like. I think the solution might be simple but need to do more testing.
 
jimzcatz said:
If you mean AMW compatible reloads we never stopped selling them, just ask your dealer.
Click to expand...

Chris?
[/QUOTE]
Are you sure about that. All the dealers I know removed them from their websites and liquidated their stock. Only place I have found them is AMW in very limited supply. Loads for the 75 mm line would be great
 
Bruce said:
Has Cesaroni made single use motors other than the O25000?

Any chance we might see other non-reload motors in the future?
Click to expand...
Yes, F and G single use motors were demoed at MWP a few years ago, I believe as part of one of Tim's contests
 
jimzcatz said:
Chris?
Click to expand...
Are you sure about that. All the dealers I know removed them from their websites and liquidated their stock. Only place I have found them is AMW in very limited supply. Loads for the 75 mm line would be great
[/QUOTE]
The 75mm CTI reloads can be used in AMW cases using the "hub". They're great, although I do use the Aerotech forward seal disk. With Gorilla gone, it's really nice to have the CTI reloads available.

Jim
 
JimJarvis50 said:
Are you sure about that. All the dealers I know removed them from their websites and liquidated their stock. Only place I have found them is AMW in very limited supply. Loads for the 75 mm line would be great
Click to expand...
The 75mm CTI reloads can be used in AMW cases using the "hub". They're great, although I do use the Aerotech forward seal disk. With Gorilla gone, it's really nice to have the CTI reloads available.

Jim
[/QUOTE]
Jim, I am aware of that. But I still like the proX loads. Thanks
 
jimzcatz said:
The 75mm CTI reloads can be used in AMW cases using the "hub". They're great, although I do use the Aerotech forward seal disk. With Gorilla gone, it's really nice to have the CTI reloads available.

Jim
Click to expand...
Jim, I am aware of that. But I still like the proX loads. Thanks
[/QUOTE]
So fill me in please. Were there reloads for the AMW cases other than the current CTI reloads? Is there an example or two? I might have missed that.

Jim
 

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