Ellis Mountain 75mm and 38mm Hardware

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mrwalsh85

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This is a bit of a cross between information share as well as a "wanted" ad... So I will post it here for now, and the moderators can do their thing if so inclined.

Does anyone have a set of 75/38mm hardware for Ellis Mountain?

I am in need of closures, and since they are no longer certified, I have no qualms with machining my own closures, to use at research launches.

If you have closures and would be willing to allow someone to borrow them for dimensioning, please let me know.

I would be interested in nozzles as well - not sure if they were SU or reusable... Regardless, if I can dimension those, I'd appreciate the opportunity.

You would receive a copy of my prints in return as a thank you.

I will cover shipping in both directions, and provide a small deposit if needed.

Thank you,
Mike Walsh
TRA/NAR L3
St. Louis, MO.
 
Have you contacted Ken Allen of Performance Hobbies?
 
I still posses a 76-3000 case, only used once, and closures. I have a cheap micrometer around here somewhere and assuming the battery hasn't died, can make any measurement you need.
 
I have a Ellis Mountain 76/7000 complete motor. It is a flat/sealed forward bulk head. It used a rear aluminum nozzle carrier, and a graphite nozzle and the only reload I know about would have been a M 1000. I have measuring stuff if you want dimensions.

Send me a PM if you want.

~John
 
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From TMT chair Alan Whitmore, once certified an item never becomes "un-certified"

Interesting. Per the TMT Policies, Ellis Mountain certification is essentially expired -- Existing stock is certified for sale and use until existing stock is depleted. I was under the guise that Ellis Mountain motors were no longer permitted for use at NAR launches, but I looksl ike I can fly my M1000 at NARAM or NSL based on this.
 
Alan told me personally certifications do not expire. Maybe we need someone to clarify this.
 
I haven't looked up the certified motor list for TRA but the NAR list doesn't have the word Ellis anywhere in it.

https://www.nar.org/SandT/pdf/CombinedMotorsByImpulse.pdf
I was under the impression that motors could be de-certified for safety reasons (NFPA 1125 8.4) but I seem to remember that they have to be renewed after so many years and if not renewed, they expire a number of years after that. Maybe that's a NAR only thing? I can't find that section in NFPA in my quick look.
 
I haven't looked up the certified motor list for TRA but the NAR list doesn't have the word Ellis anywhere in it.

https://www.nar.org/SandT/pdf/CombinedMotorsByImpulse.pdf
I was under the impression that motors could be de-certified for safety reasons (NFPA 1125 8.4) but I seem to remember that they have to be renewed after so many years and if not renewed, they expire a number of years after that. Maybe that's a NAR only thing? I can't find that section in NFPA in my quick look.

This is a bit of a thread drift, but I'm ok with that.

I guess we need @Steve Shannon and/or @Alan Whitmore 's clarification on this. I certainly do not want to stir the pot, but I certainly would like to be able to enjoy some of these treasures that I've uncovered over the years.
 
A couple years ago the three certification organizations, in discussions with the three major motor manufacturers, agreed that having motor certifications expire for no other reason than elapsed time since testing was probably not necessary. NFPA 1125 does not require retesting due to elapsed time. NFPA 1125 does allow the certification organizations to require retesting if a motor is changed in a way that exceeds design tolerances.
As a result, TMT reworked its policies and procedures manual. That is the version that is available on the TMT page of the Tripoli website.
I believe that NAR S&T and CAR MCC will revise their manuals at some point in time, but that’s not up to Tripoli to do. We provided them with our manual early on.
However, even though we made it so that motor certifications no longer expire as a function of time since certification, we did not renew the certification of any motors that had previously been declared as expired by a certification organization. Unfortunately, we had a long confusing period where none of the organizations did what our own policies said should be done. During that time none of us marked motor certifications as expired. Before that some motors were expired according to our commonly held policies. The best current record is probably the combined list on the NAR site, but Alan has been doing a fantastic job of wading through the records of previous TMT chairs to figure out just where we are. I don’t know where that leaves us with respect to Ellis motors. Obviously they are no longer in production and perhaps that fact plus the possibility that they could have been expired by an earlier TMT chair is a good reason to leave them off the combined list.
 
For your planned M1000 use at NARAM or NSL, NAR has/had a program to allow motors with expired certs to be used as long as they weren't decert'd for safety reasons (Ellis Mountain J350?). It was designed to gather data about old motors. I don't know if that is still an option for your Ellis M1000 but I would check with both NAR about the program and with the groups running NARAM and NSL.

@Steve Shannon could an expired motor (not for safety reasons) be used at a TRA research launch?
 
For your planned M1000 use at NARAM or NSL, NAR has/had a program to allow motors with expired certs to be used as long as they weren't decert'd for safety reasons (Ellis Mountain J350?). It was designed to gather data about old motors. I don't know if that is still an option for your Ellis M1000 but I would check with both NAR about the program and with the groups running NARAM and NSL.

@Steve Shannon could an expired motor (not for safety reasons) be used at a TRA research launch?
Yes, expired motors (not safety decertification) have always been allowed at Research launches.
 
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