CTI case

the rocketry show
eggtimer rocketry
Wildman Rocketry
The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Getmore

Getmore

Well-Known Member
TRF Supporter
Joined
Jun 27, 2012
Messages
5,439
Reaction score
121
I just purchased a 38/5 grain case it is old but in good shape. I flew a I 350 smoke Sam over the weekend and I had a real hard time to get the load in the case I didn't think I would ever get it in there but with brutal force it went in and had a good flight with it. Now my question is will this be a on going thing with this case? Will I have to use a bearing press to get a load in this thing. Just kidding. The case is very clean and next time I use it I will load it at home so if I need to sand the liner some I can do it in the AC instead of %&$%&#@#$% at the field. Thanks for the help.
 
Last edited:
I have had this happen a few times. I would not sand the liner. Spray inside of case with a little lube it should go in a lot better.
 
Yeah, spray silicone is actually recommended by CTI. I used it for the first time at LDRS and it made motor clean up WAY easier. Another benefit!
 
Thanks I wanted to spray some WD in it but wasn't sure. Why not sand the liner? On AT I just peal a thin peace of card board off and slip it in.
 
Having the exact same problem with my CTI 4g case. It's a brand new case! The grains seem to be correctly sized, it's just the liner that's the problem. Silcone spray has NOT helped. I had a used nozzle section of a spent motor so that I could beat that one up in attempt to get the liner in,... but this time that won't even work.. So now, I have removed all the grains from the liner and put it in the freezer and put the case out in the shed (110f). We'll see if that works. #@$!! Ridiculous!

What's the solution to this problem? (Besides using the cases for wind chimes.)
 
Last edited:
Reloads are often a very tight fit in my 2g and 3g Pro38 CTI cases. They go most of the way in - the difficult part seems to be actually engaging the threads and drawing in the aft closure. I haven't tried lubricating the case or liner, but I was shown a pretty good trick at LDRS this weekend (thanks, Tim!).

[This is not necessarily an approved procedure - use at your own risk.]

Pull the aft closure/nozzle assembly off of the reload (already mostly inserted into the case), insert a CTI 38mm spacer (open end first) against the liner, and push the spacer against a hard surface. That easily takes care of that last 1/4" or so. Remove the spacer, replace the aft closure, and screw it fully into the case. All good!

Mark
 
Last edited:
Guess What?....... putting the liner assembly, minus the grains, in the freezer for an hour, then raising the temperature of the case to 110f WORKED ! The liner slid in with 1/10 the force I was using in my earlier attempts.
 
Thanks for this tip. I had trimmed a used 38 nozzle to perform this, but it needed to be longer. The spacer is what I needed.

markjos said:
Reloads are often a very tight fit in my 2g and 3g Pro38 CTI cases. They go most of the way in - the difficult part seems to be actually engaging the threads and drawing in the aft closure. I haven't tried lubricating the case or liner, but I was shown a pretty good trick at LDRS this weekend (thanks, Tim!).

[This is not necessarily an approved procedure - use at your own risk.]

Pull the aft closure/nozzle assembly off of the reload (already mostly inserted into the case), insert a CTI 38mm spacer (open end first) against the liner, and push the spacer against a hard surface. That easily takes care of that last 1/4" or so. Remove the spacer, replace the aft closure, and screw it fully into the case. All good!

Mark
Click to expand...
 
Yep, spacers. Forget the fridge thing. You dont wanna subject that stuff to such temp changes until DURING flight
 
lw_silicone_hres.jpg
I keep a can of this in my range box, usually a quick shot inside the case works. But I have encountered the occasional stubborn reload, so I go to the spacer method mentioned above.
 
(Spacer) That's what one of the vendors used to get the last 1/4 " in when I gave up on my attempt. Next time I try a CTI load I will use some thin lube if I need to.
 
Last edited:

Similar threads

pfhorwath
How do you deal with a too tight motor case?
Replies
10
Views
718
pfhorwath
pfhorwath
manixFan
Sold 75mm green anodized snap ring cases – 19-5/8" and 30-7/8" (3500Ns & 6000Ns) New Old Stock
Replies
6
Views
705
CaptHaywire
CaptHaywire
dvdsnyd
Damaged 38mm 4 grain case recommendations
Replies
5
Views
476
dvdsnyd
dvdsnyd
J
75 mm crossloads
Replies
13
Views
898
jd2cylman
jd2cylman
Fuddrucker
Sold Full sets CTI 29mm and 38mm cases.
Replies
1
Views
485
ecargmij
ecargmij

Latest posts

Back
Top