The nosecone to my MX-774 looks like injection mold, as it's pretty thick. It came in two parts; the cone and the base/adapter section that had to be glued with plastic cement. As I said, I was disappointed when I saw the plastic nosecone as I really wanted one that was sharply pointed. Maybe one of these days I'll get an equivalent balsa cone from SEMROC to compensate.

__________________
Dave, NAR # 21853 SR.

Yes, I think I recall seeing those recommended engines (the 13 mm ones) in those later Centuri catalogs. Coupled with the sleek style and boat tail the MX-774 has, I knew it'll be an easy high flyer. That's why when I flew her at NSL-2004 (Hearne, TX) I used the Quest A6-4 (I was just getting back into model rocketry then after a 22 year absence) to keep it low, but those Quest engines ejection charges shot a lot of black soot that marred the white finish to the upper body tube of my model. But you're right, I think the 1/2A's 13 mm from Estes should be a good choice.

__________________
Dave, NAR # 21853 SR.

Yep, your MX-774's two-piece PNC-89 nose cone is the earlier injection-molded version. The later blow-molded version (see: http://www.postwarv2.com/mx774/flyi...turi_mx774.html ) was thinner-walled and considerably lighter, and its tip appeared to be more rounded than that of the injection-molded version.

If Semroc doesn't already make it (they *do* make a balsa copy of the injection-molded PNC-89 for their Centuri Spartan kit, see: http://www.ninfinger.org/rockets/ca...75rt/75rt8.html ), they (or Sandman) could make a custom sharp-pointed BNC-89 for your MX-774.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

Thank you. The 1/2A6-2 (one of the MX-774's original recommended motors) should also yield pleasing flights, and the Estes A8-3 should give flight profiles very similar to those of the Quest A6-4, minus the soot. :-)

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

If I use the A8, I'd go with the A8-5 delay. I know they're hard to find in most retailers, but we have a local mail order vendor who has an excellent selection of Estes/Quest/AT engines that I can order from and get extra fast service (http://www.launchpad2000.com/). By local, I mean here in the Houston area where I live, but they take orders from anywhere......

__________________
Dave, NAR # 21853 SR.

Mine is the two piece, orange nose/white shoulder as well.

__________________
David Stribling
NAR 18402 SR
But it is rocket science!
Get yer Barrowmans here

The one that came with mine was all red, including the base and base plug.....

__________________
Dave, NAR # 21853 SR.

You're right--the MX-774 only weighs 1.1 ounces without a motor installed, so like the Estes Viking (and Centuri Viking) and Wizard, it should use an A8-5 due to its low mass and low drag. Thank you for providing the LaunchPad2000.com vendor link--A8-5 motors are also scarce "on the rack" here in Fairbanks!

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

...contrasted with...Judging by the Centuri kits I've seen, red seemed to be the most common color of their plastic nose cones. The plastic nose cones sections in Centuri catalogs said that they were "molded in bright colors," however, and I have seen examples of other nose cone colors in Centuri kits. These include blue injection-molded PNC-89s in Screaming Eagle kits and blue (as well as red) PNC-54s in Star Trooper kits. Also, I once saw a yellow #7 size injection-molded nose cone in an eBay auction that I failed to win. All of the blow-molded Centuri nose cones I've seen (in a Twister kit and in the online photo of the MX-774 kit) were red, but two kits are admittedly a very small "sample" on which to base a conclusion--they might very well have been blow-molded in other colors.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

Bumping an old thread I know...

First, I have been comparing the G. Harry Stine MX-774 drawing to Pete Alway's ROTW drawing and have a question. I think I am mis-interpreting the ROTW drawing: is the end of the cylindrical body/start of the ogive at STA 174.15, or is that just showing the end of the cable channels? G. Harry's drawing seems to indicate the top of the cylinder is the top of the black stripe (which would translate to STA 154.1 if I did my math right )

Second, while searching for some higher resolution pictures to answer my question above, I came across a thread on nasaspaceflight.com about gimbaling engines, and somebody posted a nice article on the early Atlas history from Spaceflight magazine. The article is in this link -- I have contacted the author about availability of any hi-res pics, especially on the launch pad.

__________________
David Stribling
NAR 18402 SR
But it is rocket science!
Get yer Barrowmans here