Looking at the D8 numbers, it's more or less a D12 with a hair longer burn time.

D12
16.84 N-s total impulse
29.73 N peak thrust
10.21 N avg. thrust
21.1 g propellant

D8
18.59 N-s total impulse
28.88 N peak thrust
8.44 N avg. thrust
22g propellant



The Quest A3 has a 2 second burn time?
13mm x 55mm
1.71 N-s Total Impulse (1/2A is 1.25)
2.79 N Peak Thrust
0.82 N Average Thrust

3.6 grams propellant

Estes A3 is 2.22 N-s total impulse.

Edit: changed slash to dash. Didn't want anybody thinking it was N over s.

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Thanks for that TB!
So, based on the above, why is the D8 so desired? I never had the opportunity to try these, so I have no experience to render any kind of opinion. Just curious.
Allen

None of us have tried them. Quest has the D5 out now, which is a long burn, low thrust motor good for gliders, minimum dia altitude flights, etc.

As for why the D8 would be desired, It is a standard size motor and is a little closer to a full D than the Estes motor. (It's about 3/4 of an A motor closer to a full D, which is 20 N-s.)

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I love sanding.

I truely think eveything comes full circle...The youth of america will again find interest in this hobby. The internet will just be the outlet for the product...taking the place of the mom and pop local hobby shop. Kids know how to surf the net and find things we older folks do not know of. My thought is the fields to launch are going away...that is a real problem. In the mean time just enjoy the current state of the hobby...we are lucky to have this upturn in the hobby.

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craftsman, builder of exotics

Those are A3 mini motors, not Centuri-type A4 mini motors as I mentioned above. Being 55 mm (~2.17") long, these new Quest mini motors are not similar to the 44.5 mm (1.75") long standard Estes (and Centuri) mini motors, and thus they are not interchangeable with Estes mini motors in Estes' (and other companies') mini motor kits. (Centuri's early longer-case mini motors soon gave way to the Estes 13 mm X 44.5 mm case size.)

Models using friction-fit motor retention could be built with the thrust ring farther forward to accommodate the 55 mm long Quest mini motors and be adapted to Estes mini motors using spacer sleeve tubes, but existing kits that utilize 44.5 mm motor clips can't use both companies' mini motors without being modified to use friction-fit motor retention. People with already-built mini motor rockets that have motor clips are out of luck if they're interested in trying the Quest mini motors in their models. Even so, I'm glad to see another source for 13 mm black powder motors in the USA.

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In the early 70's built a Saturn V with the dual motor mount system (3 C motors or one D motor). A sealed one of those kits just sold on E-Bay. (I did not get the opportunity to push the final price up higher for the eventual winner ....pretty sure I was not ready to out bid the final winner....). Anyway, does anyone know why the re-released kits don't or can't have the dual mount option?

Anyone know how difficult it would be to install a dual mount system in the out-coming kit. Anyone have plans for the dual mount kit?

I got involved in the hobby in the '80s, when shopping malls had hobby stores (remember World of Science?? What a loss that it's gone- to hobbies and intelligence in general!). I've been in Tucson for 4 years now and have only found two hobby shops- one local and more geared to R/C, the other a Hobby Town USA (used to be two of those here in town when I first moved in). HT USA carries a fair amount of rocket kits, but no reloadable motors. If not for the internet there'd be no way to feed my fix, but how many "small" shops can the 'net support?
I too am frustrated by the lack of flying space- we have many local parks but there is too much infrastructure to make a great flying field (lights, backstops, etc). I AM in the desert, but I'm not familiar with the laws and regulations about flying on land of unknown ownership or BLM- so if someone can educate me, please do! My favorite field for MPR is land up by my buddy; desert hardpan relatively clear of large rocket-eating vegitation, but now that housing construction is slowly (thank god it's coming back!) picking up out here, it won't be long before I'll have to abandon it (it's currently land abandoned by the developer(s) of an enourmous housing community).
To build on other's comments, I think it was a perfect storm of calamaties for our hobby- video games came out pushing pressure on hobbies in general, which caused the shops to dry up, which caused a huge decrease in exposure. To be honest, if I hadn't seen an announcement in the local paper about our town's rocket club holding a launch I wouldn't be into the hobby again (exposing my two little guys to it too- currently too young to do it on their own, but will some day I hope!).
I do think the recent airing by Discovery Channel of LDRS will help gain exposure, but will it be good exposure? They focused on the "flash" of the event- the odd-ball rocketeers that probably initimidate more than inspire and their odd contraptions (which didn't really work all that well but were impressive to a current-rocketeer (appologies if anyone featured is a member here!)); so where's the satisfaction? I think a noob would see that and say, "All that time, effort and money to see something I built explode??". We need people to see the rewarding events- the reason we plunk down hard-earned cash for the MEAT of the hobby (BP 3FNC ain't sexy, but it works!). Once we build that base then the thrill of trying something new takes over. Additionally, in terms of start-up costs, I can't think of a cheaper hobby than rocketry! That should be a huge advantage for us.
Sites like Facebook help a little- I've been posting video and pictures of my launches there which has generated a little interest and reawakened the beast in a few of my old friends, but we need another "October Sky" event to really ignite things.
To close, I do think now is not a bad time to be a rocketeer, but I was out of the hobby myself during the dry spell in the '90s and early '00s (sorry 'bout that!! highschool and college got in the way.) Marketers are bringing back all sorts of things from my childhood- from movies to toys, so hopefully they'll run out of ideas and be forced into pushing rocketry! Please, God, let them at least run out of movies to remake!!

Awesome thread and fantastic question to the OP!!

The new Saturn V will almost certainly not have a dual mount system.

There has been at least one commercial multi-mount kit for the Saturn V. It allowed for all sorts of cluster combinations. I do not believe that the maker is still in business.

However, adding a swappable mount isn't rocket science. You would replace the included stuffer tube with a tube large enough to fit all of the cluster combinations you wish to use.

The 1970 vintage Saturn V used a "BT-63" which a BT-60 slipped into; the swappable motor mounts were pieces of BT-60 with the appropriate motor tubes inside.

You can also use bare centering rings instead of a slip tube. BMS sells many cluster-mount centering rings, and will custom burn others for you.

I've seen all kinds of talk about dual mount systems. TMRK has made this available for about the past 8 or 9 years. You can find the system here:

http://tmrk.rocketshoppe.com/parts.htm

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Are they still in business, as their web presence has not been changed in about 18 months?