closure requirement list

watermelonman · Nov 18, 2014

Apparently CTI Pro38 casings do not need closures, but some of their other sizes do, and may differ by whether fore, aft, or both are needed, size by size.

Has anyone got a list?

It looks like Aerotech casings are sold with any and all closures they need, unless you are explicitly buying by parts. That sure makes it easier, though I could be mistaken.

edwinshap1 · Nov 18, 2014

If you buy a casing then it's just the tube, but if you buy a motor then it's all closures and seal disks (if applicable) provided. Usually you can buy 1-2 motors in a given size and casings for the rest of the lengths.

List goes:
CTI 24,29,54: Rear closure only
CTI 38: no closures
CTI 75,97,150: forward and aft closures

Aerotech 18,24,29,38,54,75,98: forward and aft closures

watermelonman · Nov 18, 2014

edwinshap1 said:
If you buy a casing then it's just the tube, but if you buy a motor then it's all closures and seal disks (if applicable) provided. Usually you can buy 1-2 motors in a given size and casings for the rest of the lengths.

List goes:
CTI 24,29,54: Rear closure only
CTI 38: no closures
CTI 75,97,150: forward and aft closures

Aerotech 18,24,29,38,54,75,98: forward and aft closures

Fantastic! Thank you so much for clearing that up.

jimzcatz · Nov 18, 2014

edwinshap1 said:
If you buy a casing then it's just the tube, but if you buy a motor then it's all closures and seal disks (if applicable) provided. Usually you can buy 1-2 motors in a given size and casings for the rest of the lengths.

List goes:
CTI 24,29,54: Rear closure only
CTI 38: no closures
CTI 75,97,150: forward and aft closures

Aerotech 18,24,29,38,54,75,98: forward and aft closures

You forgot AT 32mm

edwinshap1 · Nov 18, 2014

jimzcatz said:
You forgot AT 32mm

I did actually put that down, but I deleted it when I realized I've never seen a 32 mm reload lol

kjohnson · Nov 18, 2014

List goes:
CTI 24,29,54: Rear closure only
CTI 38: no closures
CTI 75,97,150: forward and aft closures

Aerotech 18,24,29,38,54,75,98: forward and aft closures
Aerotech 24, 32 RC: Rear closure only

kj

watermelonman · Nov 18, 2014

Anyone know exactly how a 6G case differs from a 6GXL, aside from the length? Why is it not simply a 7G case?

Crumb fire · Nov 18, 2014

watermelonman said:
Anyone know exactly how a 6G case differs from a 6GXL, aside from the length? Why is it not simply a 7G case?

Each grain is a little longer than normal grain.

watermelonman · Nov 19, 2014

Crumb fire said:
Each grain is a little longer than normal grain.

Oh! That makes so much more sense. I kept thinking there was a single XL grain that was an odd shape or size, because of that odd XL spacer. Now I see, though, that the XL spacer turns the 6GXL into a 6G equivalent.

Thanks!.

SCrocketfan · Nov 19, 2014

So, for pro54, can you adapt a 6GXL case down to 6G and 5G, or only 6G? What about for the 75mm 6GXL casing (I haven't heard of any adapters for them?)

I don't think spacers work in the 29mm and 38mm 6GXL casings, but are there any adapters that work?

watermelonman · Nov 19, 2014

SCrocketfan said:
So, for pro54, can you adapt a 6GXL case down to 6G and 5G, or only 6G? What about for the 75mm 6GXL casing (I haven't heard of any adapters for them?)

I don't think spacers work in the 29mm and 38mm 6GXL casings, but are there any adapters that work?

Once you have the XL gap spaced out, you can apply regular spacers to get down to where you want to be. That is how 38mm works at least; I do not see a Pro29 XL spacer at all!

I bet Cesaroni still recommends a maximum of two spacers in any given configuration, though.

alex_car763 · Nov 19, 2014

The Pro29 6xl casing is a true 7G. You can adapt that casing down to a 5 using spacers. Not sure on the 75 but gut says it's the same because I don't recall multiple spacers for Pro75

SCrocketfan · Nov 19, 2014

alex_car763 said:
The Pro29 6xl casing is a true 7G. You can adapt that casing down to a 5 using spacers. Not sure on the 75 but gut says it's the same because I don't recall multiple spacers for Pro75

So 38 and 54 have longer grains for XL, but 75 and 29 are 7 grain. Now I think I might have to get a 29mm XL casing for some better I options…
75mm also makes sense.

bobkrech · Nov 25, 2014

SCrocketfan said:
So 38 and 54 have longer grains for XL, but 75 and 29 are 7 grain. Now I think I might have to get a 29mm XL casing for some better I options…
75mm also makes sense.

The 7th XL grain is shorter than a regular grain in the Pro38 and Pro54 motors.

https://pro38.com/pdfs/Pro38_Case_Spacer.pdf

https://pro38.com/pdfs/Pro54_Case_Spacer.pdf

Bob

CarVac · Nov 26, 2014

bobkrech said:
The 7th XL grain is shorter than a regular grain in the Pro38 and Pro54 motors.

https://pro38.com/pdfs/Pro38_Case_Spacer.pdf

https://pro38.com/pdfs/Pro54_Case_Spacer.pdf

Bob

No, it is longer in the 38mm.

bobkrech · Nov 28, 2014

CarVac said:
No, it is longer in the 38mm.

My bad. The XL grain spacer is shorter than a 1G spacer in 38 and 54 mm because the XL propellant grain length equals to a XL spacer length plus a 1G spacer length in those diameters.

Bob

watermelonman · Nov 30, 2014

bobkrech said:
My bad. The XL grain spacer is shorter than a 1G spacer in 38 and 54 mm because the XL propellant grain length equals to a XL spacer length plus a 1G spacer length in those diameters.

Bob

There is no 7th grain, but rather 1-6 are longer. The XL spacer drops the 6XL casing back to a regular 6, other than that it does not correspond to other lengths. In other words it is six times the length gap between a regular grain and an XL grain. Man does this get confusing fast.

CarVac · Dec 1, 2014

bobkrech said:
My bad. The XL grain spacer is shorter than a 1G spacer in 38 and 54 mm because the XL propellant grain length equals to a XL spacer length plus a 1G spacer length in those diameters.

Bob

Not quite right.

In 54mm, the 6GXL is less than one grain longer than the 6G. You can use one slightly shorter "XL" spacer for 6G loads, or one XL plus one regular spacer for 5G loads.
In 38mm, the 6GXL is more than one grain longer than the 6G. You can use one regular spacer plus the small XL spacer ring for 6G loads, or two regular spacers with the small XL spacer ring for 5G loads.

Bat-mite · Dec 1, 2014

My head hurts. No one told me this would be rocket science!

closure requirement list

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