CTI Discussion Thread

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I recently bought a new Pro38 2 grain case. It is a darker anodize than my cases from years ago. This weekend I used it Saturday and had a hard time getting the reload in it. I put one end on the ground and pushed down hard to get it in and then had to use pliers to screw it the rest of the way in. I figured maybe was just that one reload but today the same issue. Even used Dow 111 Silicone on it but really didn’t help. These reloads are from 2002 vintage 244H153’s that are oop now. Have the dimension specs changed since 2002 or is this case out of spec?
 
That is sad if that is how your vendor treats you. We have 2 CTI vendors in the south and they have always covered warranty, usually on the spot if they have H/W & motor in their inventory.
Wildman’s used to do the same thing .
However after waiting for months and in some cases over a year for replacements we can no longer have CTI use our inventory to take care of there warranty issues .
When CTI sends the replacement we contact the customer to let them know it has arrived.
BTW. Cesaroni does not pay for shipping either . Leaving that for the dealer to explain to the already upset customer.
 
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Wildman’s used to do the same thing .
However after waiting for months and in some cases over a year for replacements we can no longer have CTI use our inventory to take care of there warranty issues .
When CTI sends the replacement we contact the customer to let them know it has arrived.
BTW. Cesaroni does not pay for shipping either . Leaving that for the dealer to explain to the already upset customer.
Well, that is not very comforting news. So basically what your telling me is I will be flying Aerotech for 29mm the rest of the year. Good information to know about now. I'm not sure I'd want my customers flying the competition for that long if it were my company. So, will Wildman keep my replacement reload until I want to pay HazMat shipping again? Which may very well be Black Friday.
 
Well, that is not very comforting news. So basically what your telling me is I will be flying Aerotech for 29mm the rest of the year. Good information to know about now. I'm not sure I'd want my customers flying the competition for that long if it were my company. So, will Wildman keep my replacement reload until I want to pay HazMat shipping again? Which may very well be Black Friday.
Yes we will hold it until you want to ship it .
 
Got the 54 mm closure yesterday. It did fit all my old cases but won't fit the new 4 grain case:dontknow: However, the 2 original closures I got when the 54s first came out fit ALL the cases. I cluster the 2 and 4 grain cases so I will be OK. (I had to replace the case and closure I loaned to the GA Southern SLI team when COVID hit.)
 
Hello all. I just purchased a 54mm 3g case and 1 spacer. This is my first 54mm case. Is there anything to watch out for on the 54mm motors and cases?

These days it seems that LOTS of folks are glueing in the forward closure of CTI 54mm loads with more success than those who are not.
 
These days it seems that LOTS of folks are glueing in the forward closure of CTI 54mm loads with more success than those who are not.
I guess I'm not following things on TRF too well. When and why did people start gluing the fwd closures? Isn't that what the case is supposed to do? Hold the closures in place.

I have a 54 6XL case with a couple spacers and fly 5, 6, and 6XL loads. I usually pick the load based on weather and field conditions, open the package and load the motor. I've never had an issue, my case keeps the closure and nozzle where they belong.
 
I have flown lots of 54mm, typically in the 6GXL size. I have taken to gluing each forward closure in now, as others have done. I had one leak a little and was very lucky for it not to be worse and destroy the case.
 
I've seen far too many forward closure failures that I now glue them in on every CTI motor and would recommend the same. Just a light seal with 5 min epoxy seems to work well enough and it doesn't add much to the prep of the motor.
 
I guess I'm not following things on TRF too well. When and why did people start gluing the fwd closures? Isn't that what the case is supposed to do? Hold the closures in place.

I have a 54 6XL case with a couple spacers and fly 5, 6, and 6XL loads. I usually pick the load based on weather and field conditions, open the package and load the motor. I've never had an issue, my case keeps the closure and nozzle where they belong.

It actually started several years ago, and it's been a continuing issue that gets discussed periodically in this and other threads. There seems to be a high degree of variability in the quality of liner cuts, both in squareness and proper length, and plenty of folks are getting high speed gas cutting type failures in the forward seal o-rings as well.

It's also been an increasing issue with the 38mm loads, although not nearly as wide spread.

As noted by 0011001100 above, 5 min epoxy seems to be the ultimate cure/preventative.
 
It's also been an increasing issue with the 38mm loads, although not nearly as wide spread.
Personally Ive seen a lot of 38mm 2g failures. But I also help out with a team and everyone has to get an L1, but we have a day of every 1 in 3 motors failing. Once we added epoxy we haven't had a single failure.
 
Personally Ive seen a lot of 38mm 2g failures. But I also help out with a team and everyone has to get an L1, but we have a day of every 1 in 3 motors failing. Once we added epoxy we haven't had a single failure.

Do you only epoxy in the black powder ejection charge after drilling the delay??
 
Personally Ive seen a lot of 38mm 2g failures. But I also help out with a team and everyone has to get an L1, but we have a day of every 1 in 3 motors failing. Once we added epoxy we haven't had a single failure.
Did you do the starter pellet modification recommended by CTI?
 
It actually started several years ago, and it's been a continuing issue that gets discussed periodically in this and other threads. There seems to be a high degree of variability in the quality of liner cuts, both in squareness and proper length, and plenty of folks are getting high speed gas cutting type failures in the forward seal o-rings as well.

It's also been an increasing issue with the 38mm loads, although not nearly as wide spread.

As noted by 0011001100 above, 5 min epoxy seems to be the ultimate cure/preventative.
I epoxy the bulkhead with 5 minute epoxy, add a additional o-ring (cant recall the dash #, bought a bag of a hundred from McMaster), and slather the bulkhead and top of liner with SuperLube.

YMMV
 
I epoxy the bulkhead with 5 minute epoxy, add a additional o-ring (cant recall the dash #, bought a bag of a hundred from McMaster), and slather the bulkhead and top of liner with SuperLube.

YMMV

Sounds like maybe 2nd o-ring should be included from CTI.
 
Do you only epoxy in the black powder ejection charge after drilling the delay??
Yes we drill the delays first then coat the outside edge of the closure in a ting layer and insert it into the liner and then wipe off the excess.

Did you do the starter pellet modification recommended by CTI?
No because most of these failures were a couple hundred feet up and about halfway through the burn (based on leftover propellant thickness). Also these are 2 grain motors and already have the fixed pellet from CTI.
 
I went to prep a CTI Pro75 M1101 reload in an Aerotech case for a flight this weekend. I've flown lots of CTI reloads this way before and never had a problem. This time, the grains didn't fit in the liner without sanding the grains, and the liner and nozzle didn't fit in the case at all. I sanded the liner extensively and can probably get it to fit by leaving the case out in the sun to expand the case (it's still very tight), but this turned what it supposed to be a 15-minute max operation into hours of frustration, to the point that I had to scrub the flight.

Production date on the reload was May 16, 2019.

I've been wondering about CTI's quality control for a while, and this doesn't make me feel better.
 
Based on what? That a couple people do it? Many do not use double O-rings and do not have any CTI CATOs.

Regarding 2-131 O-rings:
View attachment 469192
I have flown many CTI 6-XL motors, mostly L265 and L935 and have never had an issue, however I started gluing my closures in several years ago. However, I have personally witnessed many such failures, including 2 from our group at Airfest last year. The failure mode is almost always the same - a gas leak right below the forward closure. I have been using epoxy on my longer CTI motors for several years - based on both the recommendation of my motor vendor and several other well-known flyers who experienced the problem. It’s far more than just a couple of people, and you ignore the advice at your own peril.


Tony

”the space shuttle survived many foam strikes until it didn’t”
 
The failure mode is almost always the same - a gas leak right below the forward closure. I have been using epoxy on my longer CTI motors for several years - based on both the recommendation of my motor vendor and several other well-known flyers who experienced the problem. It’s far more than just a couple of people, and you ignore the advice at your own peril.

If you actually read my post, you will see I only addressed the issue of CTI supplying an extra O-ring. I never mentioned epoxy.
 
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