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98/17500 or Bigger Case

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I FOUND IT! After months of searching. Harry had one, you guys were right, and he’s also a great guy as you mentioned, pleasure to speak to and do business with. Special thanks to John H, I heard you called Harry last night to check on it, very nice of you! Thank you all for the pointers, thank you Eric for the offer as well, I’d of definitely begged you to sell it to me :)

CHEERS!
 
From my vast archives and useless info: ;)

98mm Drawn tubing & Liners from AMW:
ID Wall OD Gap
Casting 3.198 0.051 3.300
Liner 3.310 0.108 3.525 0.0050
Casing 3.549 0.156 3.860 0.0120

Nozzle and closure step OD is 3.300".
 
From my vast archives and useless info: ;)

98mm Drawn tubing & Liners from AMW:
ID Wall OD Gap
Casting 3.198 0.051 3.300
Liner 3.310 0.108 3.525 0.0050
Casing 3.549 0.156 3.860 0.0120

Nozzle and closure step OD is 3.300".

Awesome John! Thank you so much. It looks like my liner and casting tube sets are close enough for government work with AMW hardware. Plus you'll get a little more propellant in there too. My casting tubes have a 3.225" ID. There will be a .021" gap around the bulkhead and nozzle shoulder. 4 to 5 wraps of masking tape and they will be centered but that may not even be needed on the nozzle end. Your thoughts?

BTW, I didn't realize the case tubing had a 3.860" OD spec. The AMW case I have measures 3.875"OD like most all other 98mm cases.
Feel free to send me any and all useless info you have. ;-)
 
BTW, I didn't realize the case tubing had a 3.860" OD spec. The AMW case I have measures 3.875"OD like most all other 98mm cases.

I think the OD should be 3.880" nominal. Probably a typo. I went out to the shed and measured my AMW case and that's what it says. Also checked the bare DOM tubing and it is 3.876". The difference is probably the anodizing.

What is the material of the liners and casting tube sets you have? Convolute phenolic cloth or kraft phenolic liner? And paper casting tubes or kraft phenolic casting tubes? Pictures? ;-)
 
What is the material of the liners and casting tube sets you have? Convolute phenolic cloth or kraft phenolic liner? And paper casting tubes or kraft phenolic casting tubes? Pictures? ;-)

Convolute wound Linen Phenolic 49" long at most. Four tubes are untrimmed and one is trimmed to about 48". If 49" is needed you get hit with a $14 oversize box service charge (courtesy of FedEx) along with slightly higher dimensional weight shipping costs (if buying enough to require an 8x8 inch box). If not, I cut them down to 47.75" to fit in a 48" long box. The ID surface is a bit rough due to the mandrels surface quality. It's the same as it's always been and I've never had issues or customer complaints. If anything it give more surface area for grain bonding. ;-)

Casting tubes are high quality spiral kraft paper, .047" thick. I have lots of them on hand currently so if a small run of any paper grade liners are desired it would only take a few weeks to get them. I just placed a liner order Tuesday so I could add to the order if I did so within a week or less.

The LE grade run $109/set. X grade would be $125/set. XX and XXX would be somewhat higher but with minimally increasing thermal resistance returns. (in my experience)
 
Seems the OP is looking for a "commercial case blessed by the rocket gods".
AMW nozzle and forward closure shoulder liner OD , from OEM spec, will fit a 3.50" liner. If the liner is made correct.
3.55"ID AMW case was made to accommodate thicker walled liners. And yes wrapping a 3.50" liner will work, but isnt that modification not allowed for commercial use ?
In the past, we, (JerryO and company) have purchased designed liners(thick convolute) and cast tubes from Franklin Fibre, Wilmington DE.
Theres a minimum purchase of $300 ?
The brown cast tubes wernt great, so different cast tubes were purchased from, I believe, Yazoo Mills, PA. Butt spiral white kraft.
 

Holee Guacamole, What a substantial liner! Although that's likely what would be needed with a high L/D motor of this type along with a decent nozzle, formula and grain design. I'm impressed.
I did overkill 38mm Garolite for AT motors with clear plastic casting tubes and can get two maybe three firings out them using the AT nozzles and parts. Me suspects at that size and flux with a 98/17500 it's a one time
shot with those puppies. Kurt
 
If anyone wants to go the route of sourcing your own liners and casting tubes, then I wish you much luck.

I have boxes of casting tubes of various sizes taking up much needed space in my shipping container that either don’t fit (thousandths too large) the intended liners or are on the very loose side which allows hot gas to the back side that will burn the tubes if not properly addressed. Franklin’s minimum prices may be lower but their tolerances are double that of my supplier. You also get to do all the work and enjoy the headaches that come with it. They don’t have the same mandrel sizes as the standard sized liners I use and I cannot speak for their quality or lack of laminate voids. Bottom line is, buyer beware. You are buying an unknown (to you) at your own risk.
Or you can buy one or more sets in any size with proven confidence from Loki Research.

BTW, I am now down to 3 sets left on my 3.55”OD LE grade liner sets pictured above for AMW/Gorilla. I also hear from Danny that his new 98/17500 Gorilla case has a 3.55” ID.
 
Scott,

PM me a discount quote for those F'ed up casting tubes and an LE liner to go with them, and I'll clear up that shipping container for you.
 
I've reached out to Dan, it appears he had a bad e-mail address for me. 3.5" ID 98mm cases up to 72" long are no problem.

Mike Fisher
 
I've reached out to Dan, it appears he had a bad e-mail address for me. 3.5" ID 98mm cases up to 72" long are no problem.

Mike Fisher

Mike saved the day! I wish I wasn’t sending requests to the wrong email though, I’d have my case already. My fault and Mike was lightening quick to reach out to me when he heard, thank you Mike! I’ll be putting the 3.55” 98/17500 Gorilla Case up for sale to try and help out Harry before I return it. I’ll only leave it up for a couple days, please email me if interested. Harry also said that Gorilla is staging for a big comeback and 3.55” may become more normal. Had my dozen nozzles and closures fit the 3.55 I would have kept it, but I have too much invested in them to not use them. 3.55 is much more appealing being that Scott has rock solid liners for them, they’d easily be reusable a few times (Per my standards...). The case is perfectly straight, and is anodized on the inside only. There’s no anodizing on the outside bc Gorilla made it too thick and had to take down the od and the green anodize with it. Thanks again everyone!
 
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