Reloadable Motor System

Discussion in 'Mid Power Rocketry (MPR)' started by geodehunter, May 21, 2019.

Help Support The Rocketry Forum by donating:

  1. Jun 23, 2019 #61

    Dave A

    Dave A

    Dave A

    Lifetime Supporter TRF Lifetime Supporter

    Joined:
    Jan 22, 2013
    Messages:
    1,098
    Likes Received:
    89
    I mentioned to AT about doing a 7 grain 75mm motor. I believe they have plans to do a SU 75/10240 motor.
    I flew my own design at Red Glare this past April.
    Since I fly all my AT 75 reloads in a snap-ring cases, I did a 7 grain version of the M1850, it simmed as an M-2353. Punched my 85# Patriot to over 5300'. Awesome flight. FB_IMG_1554987548986.jpeg
     
    jd2cylman likes this.
  2. Jun 27, 2019 #62

    Steve Shannon

    Steve Shannon

    Steve Shannon

    Well-Known Member

    Joined:
    Jul 23, 2011
    Messages:
    5,184
    Likes Received:
    1,432
    Location:
    Butte, Montana
    Sorry I didn’t see this earlier. Here’s how I did it starting out (as recommended by my Prefect/TAP) and this is what I suggest to people who come to me wanting to certify.
    1. Order at least two motors for each level you wish to certify. That way if something minor disqualifies your attempt you can follow it up with a successful flight.
    2. Don’t order them to be sent to you. Paragraph 6.1.(9.) in NFPA 1127 allows a single motor to be sent to a person for purposes of certification, but you can have multiple motors sent to someone who is certified appropriately. So, have them sent to your Prefect or a certification witness who is certified.
    3. If possible borrow the case from your certification witness. I regularly loan my cases to people who are certifying. If they ruin them or lose them they are obligated to replace them. They are also obligated to clean them before returning them. After a few flights people form a clearer idea of what kinds of cases they want to invest in. This inexpensive experience helps them make that decision.
    4. Your Prefect or club President may also be able to tell you when a club or group order is going to happen. That saves a lot of money on hazmat and shipping. When I order group orders they are usually about $3000 worth at a time and I prorate the shipping based on % of the order, so if a person buys $1000 worth of the $3000 order they pay 1/3 of the shipping. The person who buys $100 worth pays 1/30th. I always pick up a few extras for my box which people can use for certifying also.
     
    Last edited: Jun 28, 2019
    mbeels likes this.
  3. Jun 28, 2019 #63

    pondman

    pondman

    pondman

    Serenity now...... TRF Lifetime Supporter

    Joined:
    Mar 23, 2011
    Messages:
    646
    Likes Received:
    85
    Excellent info Steve!
     
  4. Jun 28, 2019 #64

    yorn

    yorn

    yorn

    Member

    Joined:
    May 13, 2019
    Messages:
    6
    Likes Received:
    2
    Wow, thank you for the info! This is an incredibly helpful post.
     
  5. Jun 28, 2019 #65

    Steve Shannon

    Steve Shannon

    Steve Shannon

    Well-Known Member

    Joined:
    Jul 23, 2011
    Messages:
    5,184
    Likes Received:
    1,432
    Location:
    Butte, Montana
    I just have to issue a correction to what I said earlier. There is a clause in NFPA 1127 that allows a single motor to be sold or transferred to someone not yet certified for purposes of certification. It’s still a better idea to have spares sent to your certification witness, but I was wrong about the requirement.
     
    yorn and dhbarr like this.

Share This Page