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38mm Dr. Rocket aft and forward closures

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Rocket2Russia

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Hey fellow rocket scientists. I just bought a Dr. Rocket 38/240 casing. Anyone have the aft and forward closures I need for this? I was told that I should be able to use the Aerotech closures so I have been told.
 

ttabbal

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Aerotech closures are the same, just different colors. I don't have any to sell, just thought I'd mention it as you seemed unsure.
 

tbonerocketeer

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Hey fellow rocket scientists. I just bought a Dr. Rocket 38/240 casing. Anyone have the aft and forward closures I need for this? I was told that I should be able to use the Aerotech closures so I have been told.
Aerotech closures work just fine. We have them in stock if you want to order some.
 

Rocket2Russia

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Thank you all for chiming in. After doing some digging I realized that could get a complete new motor for less than the cost of the used Dr. Rocket casing plus the closures. I am still somewhat new to this and still just a novice Jedi. Unless I find the closures used (and cheap) I will just buy a complete new motor at LDRS or sometime after that.
 

Rocket2Russia

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Great question and thanks for chiming in Jim. Performance Hobbies lists the 38mm forward closure for $25 and the aft for $31 which add up to $56. Add the $25 for the used casing and that comes to $81. Performance sells the complete 38/240 motor for $76. My goal is to get either the 4" or 5.54 Loc Precision V2 being as I am a WW2 nerd. Should I get the 38/240 casing and then at a later date pick up a complete 38/120 if I go with the 4" or a 38/360 if I go with the 5.54? That way I'd have a wide range of motors to choose from. I am leaning towards just getting the 38/240 new and I can use it with either kit. I am brand new to the world of RMS. I have being doing my homework and reading the forums but like a lot of things the more you learn the more questions you have.

I plan to be at LDRS on 4/7 and 4/8 with my Nikon gear. If any of you want photos of you with your rockets just grab me. It's the least I could do in return for your help.
Thank you,
 

noffie79

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Maybe you could get the 360 and the 720 casings, a set of closures and the RAS (reload adapter system). Then you could fly countless reloads with just having invested in two cases. That's what I've done with both AT and CTI. Just an option!
 

Rocket2Russia

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Maybe you could get the 360 and the 720 casings, a set of closures and the RAS (reload adapter system). Then you could fly countless reloads with just having invested in two cases. That's what I've done with both AT and CTI. Just an option!
A 360 case with reloads costing $40 each? Maybe after I hit the Powerball :) When I first got started I was whining about paying $3.50 per each LPR flight. I think I'll stick to the 240 case.
 

Steve Shannon

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A 360 case with reloads costing $40 each? Maybe after I hit the Powerball :) When I first got started I was whining about paying $3.50 per each LPR flight. I think I'll stick to the 240 case.
Noffie79 is really spot on with his advice. With the RAS you can fly the loads intended for the motor or loads that are one or two grains smaller. So, with the 360 case, an aft closure, and the RAS, you'll be able to fly the loads meant for 360, 240, and 120 cases, without buying any more cases. Then, when you decide that you want to fly your L2 flight, you'll be able to pick up just the 720 case.

By the way, watch for certification special sales. Sometimes vendors and motor manufacturers have sales where you get a motor case at a significant discount when you buy the reload for your certification flight.

In the mean time you can always fly single use motors without buying cases and closures.


Steve Shannon
 

Rocket2Russia

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Noffie79 is really spot on with his advice. With the RAS you can fly the loads intended for the motor or loads that are one or two grains smaller. So, with the 360 case, an aft closure, and the RAS, you'll be able to fly the loads meant for 360, 240, and 120 cases, without buying any more cases. Then, when you decide that you want to fly your L2 flight, you'll be able to pick up just the 720 case.
Does the RAS take the place of the of the forward closure? I like the idea of being about to use smaller loads in the 360 case. It's like a one size fits all....sorta.



In the mean time you can always fly single use motors without buying cases and closures.
I like the idea of the RMS as in the long run it seems like it would be cheaper than buying the single use motors.
Thanks to all who chimed in.
 

Steve Shannon

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I have the 54mm RAS and it comes with a threaded retainer and floating forward closure that is held in correct location by the insertion of the spacers above it.


Steve Shannon
 

Rocket2Russia

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So regardless of whether I get the 4' or 5.54" V2 I guess my shopping list should be 360 case, an aft closure, and the RAS? Anything else? I guess I'll want to pick up a Jolly Logic chute release for $130 while I'm at it. I learned a ton by starting this thread. Thanks so much everyone! I looked for a sticky about RMS but didn't see one. (hint, hint)

I like the cost of the smaller V2 but I like the size of the bigger one. The smaller will be easier to fit into my less than 400 sq ft apartment where my workbench and kitchen counter are one in the same. I need for that Powerball to come through!!
 

MikeyDSlagle

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A 360 case with reloads costing $40 each? Maybe after I hit the Powerball :) When I first got started I was whining about paying $3.50 per each LPR flight. I think I'll stick to the 240 case.
I used to be in this very same state of mind, but I got over it. You'll hear folks say "I can fly x amount of G motors for the cost of 1 I motor. Yes, but a G doesn't have the smoke or sound of an I motor. I COULD eat 10 cans of Vienna sausage for dinner, but I prefer one steak.

Here is an option:
https://www.csrocketry.com/aerotech-38/120-720-combo.html
150 bucks and your flying G through J. Don't want the 720 case? Sell it on here for below retail, it'll move fast.

Just think about this though. If you have multiple cases with only one set of closures what are you going to do if your rocket lands in a tree or pond or on a power line on the first flight? I had one land on a power line recently. But I had other cases to fly that day. Unfortunately my chute release was hanging there too, so that changed things too.

If you're considering buying a complete motor, opt for the 360. Yeah the loads are more expensive but you won't be buying a case you already have just to save a few bucks. And you may have one of those perfect days that begs you to put an I in your V2. I would definitely suggest grabbing a complete 38/360 motor, it has a wide range of propellants, H through I. It'll probably be only a few bucks more than the 240 motor.

Mikey D
 
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M2Rocketry

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If you pick up the 720 or 600 case then the RAS would bring them down to meet the 240 ie 720 with spacers becomes a 600 or 480. The 600 would become a 480 or 360 then you have the 240 which could be used as a 120.
Yes the RAS provides a standard front closure so you would only need the rear. Unless you wanted a special front like threaded etc. The 720 would cover you from the L1 to L2 range with Is and small Js.
Cost is cheaper per newton as the motors get bigger. Something to think about. And the 38mm size is very cost effective system for basic high power rocketry.
I may have most of the items you're looking for, including some Dr Rocket cases and closures, listed here.
 

Rocket2Russia

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Just think about this though. If you have multiple cases with only one set of closures what are you going to do if your rocket lands in a tree or pond or on a power line on the first flight? I had one land on a power line recently. But I had other cases to fly that day. Unfortunately my chute release was hanging there too, so that changed things too.
After looking at one vendor's web site the 360 case, an aft closure, and the RAS came out to about $100. If I buy that combo and sell the 720 for $50 I'll be at the same place plus I'll have to make a trip to the post office. I won't have to worry about not having another case to use in case mine gets stuck in a tree. I don't plan on having an arsenal of $200 rockets. I think if I asked you guys if I should get the $110 kit or the $210 version you'd tell me to get the US Rockets 10' version for $900. Of course I am kidding.

Life was much simpler before I knew all this existed. Go to the LHS pick up a pack of motors and head to the club launch.

Thanks again folks.
 

Rocket2Russia

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If you pick up the 720 or 600 case then the RAS would bring them down to meet the 240 ie 720 with spacers becomes a 600 or 480. The 600 would become a 480 or 360 then you have the 240 which could be used as a 120.
Yes the RAS provides a standard front closure so you would only need the rear. Unless you wanted a special front like threaded etc. The 720 would cover you from the L1 to L2 range with Is and small Js.
Cost is cheaper per newton as the motors get bigger. Something to think about. And the 38mm size is very cost effective system for basic high power rocketry.
I may have most of the items you're looking for, including some Dr Rocket cases and closures, listed here.
So a 480 case would also cover 360 and 240? If I have this would I even bother to fly 120 motors?

I can't thank you folks enough. I have really learned a lot from this thread.
 

Steve Shannon

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I would suggest that if money is tight, use DMS motors until Aerotech and its vendors offer a certification special. The prices are not terribly different and you've already commented that you wouldn't be flying many motors at the higher end of the price range. In the mean time look at the yard sales here. If you haven't already, start attending local club launches and meetings. You may run into some deals there. There are a lot more local sales going on than what you see here.


Steve Shannon
 

M2Rocketry

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Yes a 480 would be spaced down to a 360 then a 240. BUT (always) if you have the 240 then going to the 600 you could have that the 480 360 and then use the 240 case you already have. The 120 case only has 1 or 2 reloads and then the issue is with your local vendor whether they will support that case with reloads. I know the guy who was one of the biggest suppliers on the west coast at launches and I don't think he carried any loads for that case because the same loads and motor hardware for 29mm were cheaper. That's another issue all together so I'll ask why not 29mm a 180 and 240 case would load a lot of h motors fairly cheap? I get the money thing but welcome to high power L1 bring your checkbook L2 bring the credit card and L3 it's time for a Black Card.
I could set you up with a deal on 29mm 180 and 240 set with closures and you would be able to fly a g75 - h250. If your staying level one then 29mm is where you need to be.

If you want to go Cesaroni you only need the case as they giveyou closures with the reloads. The loads cost a few bucks more but the hardware is cheaper including the spacers. A 2 grain Pro 38 will fly an H100 - H400 in 9 different loads and every one of them is less than $35. Aerotech offers 5 loads in the 240 (2grain) case and 5 loads plus closures for $27 - $25 ea. The 3 grain CTI case offers 9 loads again all I impulse at $41 ea. average. The spacers are $9ea.

I have used Pro 38mm 2 3 and 4 gr cases for $20ea.
I have used Rouse Tech 180 case and Aerotech 240 complete motor with seal disc for $70
I also have new Rouse Tech closure set rear and standard open forward for $50
 

MikeyDSlagle

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Aerotech 38mm cases are cheaper than 29mm cases. And loads for the same class case are the same price, ie AT 29/240 loads cost the same as AT 38/240 loads. The 29/360 is a bit cheaper but there are only...two?

I'll really get you thinking...check out the Loki 38/120. Hazmat free loads and come two to a pack for ~$35. But no starter, which adds to the cost.

Back to the original question. If all you want are closures for the AT 38/240 motor, then buy just the closures. Don't start thinking about I can save a few bucks by doing this or that, it'll make you sick. Yeah you can buy a new motor cheaper than you case + closures. But you have a case, just grab the closures. I recently bought a motor with the wrong forward closure so I had to buy another plus a washer. I came out paying more in the end, for used parts. Live and learn.

Talk to Mike (M2Rocketry) he probably has some closures. I've bought from him myself.

And in this hobby, never is a 4 letter word. Lol. Just because you don't plan something doesn't mean it will not happen.

Good luck to you. If Mike can't help, maybe someone will chime in.

Mikey D
 

Rocket2Russia

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I am completely overwhelmed by the generosity of people on this forum. Thanks to all for chiming in. As a result of your efforts I have learned a great deal. Someone should consolidate all of these posts into a sticky titled something like "Buying your first motor case? Here are things to consider". After considering all of your input I am leaning toward getting a 38/480 case and the RAS. I don't think a 600 is needed because even if I were to hit the Powerball I don't see myself spending $60+ for a rocket flight. The guy next to me can do that and I'll just watch his flight :) If I decide to go with the 5.54 V2 a 120 motor might be too wimpy. I don't mind spending some money on this stuff but everything in moderation.

There are tons of rocketry videos on youtube but other than the Apogee Rockets and John Coker's videos they are just footage of launches without painting a picture of what's going on. I plan on being at LDRS on 4/7 and 4/8 shooting footage for a short documentary on LDRS. If you would like to talk on camera about LDRS or your project I would love to hear from you. Please allow the below clip to serve as my demo reel:


[YOUTUBE]dyhYXcJz2mM[/YOUTUBE]
 

Rocket2Russia

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Nice video work!
Thank you very much Mr. Low. On Your Mark, Get Set, MOW1 was shot over five years. It's the story how a family devastated by Huntington's disease uses the sport of lawn mower racing to raise funding for and awareness of the disease. It has screened at several film festivals in the US and has screened in Bangkok. I plan on releasing a DVD in the next few months. If I may be so bold to put in a plug for the web site it is http://www.mowermovie.com. There are mow clips there.
 

tomsteve

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mike, your generosity to do some filming and documenting flights deeper than just," pml patriot on AT K550 goin in 5,4,3,2,1" is awesome! I used to have some vcr tapes( for youngens, thems them big huge cassette tapes for video. for youngens, cassette tapes came after 8 track. for youngens...oh hell....this can go on and on!) of a couple BALLS launches and LDRS from the 90's and wore em out. the one thing I really liked about them is listening to the rocket owners talk about the rocket- construction details and all the cool stuff.
im sure you will find fliers willing to talk about their rockets. id love to hear boris katan talk about his insanely awesome rockets.
plus Chefice99’s 1/2 Scale Nike-Ajax- just lookin at the pictures has me wanting to learn about the build
 

Rocket2Russia

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Tom (or is it Steve?),
I was at work last night and came up with the thought that I'd shoot a MDRA launch entirely on Super 8 film. Funny that you should mention 8 track tapes and VCRs. Unlike those technologies Super 8 film is still very relevant.
 

tbonerocketeer

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I used to be in this very same state of mind, but I got over it. You'll hear folks say "I can fly x amount of G motors for the cost of 1 I motor. Yes, but a G doesn't have the smoke or sound of an I motor. I COULD eat 10 cans of Vienna sausage for dinner, but I prefer one steak.

Here is an option:
https://www.csrocketry.com/aerotech-38/120-720-combo.html
150 bucks and your flying G through J. Don't want the 720 case? Sell it on here for below retail, it'll move fast.

Just think about this though. If you have multiple cases with only one set of closures what are you going to do if your rocket lands in a tree or pond or on a power line on the first flight? I had one land on a power line recently. But I had other cases to fly that day. Unfortunately my chute release was hanging there too, so that changed things too.

If you're considering buying a complete motor, opt for the 360. Yeah the loads are more expensive but you won't be buying a case you already have just to save a few bucks. And you may have one of those perfect days that begs you to put an I in your V2. I would definitely suggest grabbing a complete 38/360 motor, it has a wide range of propellants, H through I. It'll probably be only a few bucks more than the 240 motor.

Mikey D
https://www.csrocketry.com/rocket-m...8/120-hardware/aerotech-38/120-720-combo.html

Is now the correct link. I've been making changes to the site and that link updated when I added the new category. Thanks for posting that mikeydslagle
 
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