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-   -   Vashon Sandpiper parts? (http://www.oldrocketforum.com/showthread.php?t=17188)

blackshire 03-31-2018 06:44 PM

Vashon Sandpiper parts?
 
Hello Doctor (and all readers herein),

I was looking at the Vashon (later Estes) Sandpiper kit (see: http://plans.rocketshoppe.com/vasho...111/Vas3111.pdf [scanned kit plans] and http://www.ninfinger.org/rockets/ca...74/74est44.html [Estes 1974 catalog listing]), and the plans indicate—in a supplemental hand-drawn diagram—that its 1.00” diameter nose cone was/is 3.00” long. Is the length figure correct? As shown in the photograph in the Vashon kit instructions (and in the Estes catalog illustration), the nose cone looks longer than that. If anyone has cloned it, which nose cone(s) is/are the best match for the nose cone in the original kit? (The Vashon Cold Propellant kits that used the aluminum V-1 and V-2 Freon motors were 1.00” in diameter, so the 0.976” Estes BT-50 tubing would be a close diameter match.) Also:

Does anyone produce duplicate decals for the Sandpiper kit? Many thanks in advance to anyone who can help!

tbzep 03-31-2018 08:23 PM

Rocket Doctor hasn't been on YORF in over two years and I think that was just to sell off some of his collection.

blackshire 03-31-2018 08:35 PM

Quote:
Originally Posted by tbzep
Rocket Doctor hasn't been on YORF in over two years and I think that was just to sell off some of his collection.
Oh...this sub-forum could use a "Sticky" that gives notice about that change.

tbzep 03-31-2018 09:38 PM

Quote:
Originally Posted by blackshire
Oh...this sub-forum could use a "Sticky" that gives notice about that change.

Though the "Ask The Doctor" subforum was probably created for a former very short term Estes employee, it has morphed into a general question type forum that we all help to answer. With all the firepower from Mr. Vern Estes himself, golden age Estes designers like Bill Simon, and the vast knowledge base of many of our illustrious "vintage" members, there is way more knowledge and history being shared on YORF right now than any one Rocket Doctor could imagine.

BARGeezer 04-01-2018 12:33 AM

Don't know if anybody makes the decals, but there is a very clean scan of the decals here:

http://www.oldrocketplans.com/decals.htm

Scroll down, it's the third from the bottom.

You can do a decent set of home printed decals from that.

blackshire 04-01-2018 01:24 AM

Quote:
Originally Posted by BARGeezer
Don't know if anybody makes the decals, but there is a very clean scan of the decals here:

http://www.oldrocketplans.com/decals.htm

Scroll down, it's the third from the bottom.

You can do a decent set of home printed decals from that.
Thank you! With a little brush-painted white in a few strategic spots (or by printing the decals on white decal film), the "stars and bars" decals wouldn't need a white-printing Alps printer to make them. My HP7520 printer might even be able to print them on decal film.

BARGeezer 04-12-2018 04:41 PM

Blackshire,
If you are looking to clone the Sandpiper (Jayhawk) then it might be easier using the Estes plans rather than the Vashon ones:

http://www.oldrocketplans.com/estes/est1389/est1389.htm

You can purchase the 3d equivalent of the PNC-50S nose cone here:

https://www.shapeways.com/product/F...tionId=42814278

Or you can save some money and go old school by gluing the canards on a balsa cone.
The BT-50 tube is 7.75" long and the BT-20 engine tube is 3.5" long (from John Brohm's reference list). You will need to draw up a custom shroud simulating the tail cone. There is a shroud generating program available here (paper cones transitions program):

http://www.rocketshoppe.com/tips.htm

"Sandpiper" was an Air Force project to develop a hybrid motor for the Jayhawk replacing the liquid hypergolic propellants with a solid fuel propellant and storable liquid oxidizer. Potentially much less problems compared to toxic, volatile hypergolics. Interesting stuff.

Anyway, I have this on my build pile as well.

ghrocketman 04-12-2018 09:03 PM

The DANGER-factor is what makes hypergolic liquid propellants FUN !

blackshire 04-12-2018 11:35 PM

Quote:
Originally Posted by BARGeezer
Blackshire,
If you are looking to clone the Sandpiper (Jayhawk) then it might be easier using the Estes plans rather than the Vashon ones:

http://www.oldrocketplans.com/estes/est1389/est1389.htm

You can purchase the 3d equivalent of the PNC-50S nose cone here:

https://www.shapeways.com/product/F...tionId=42814278

Or you can save some money and go old school by gluing the canards on a balsa cone.
The BT-50 tube is 7.75" long and the BT-20 engine tube is 3.5" long (from John Brohm's reference list). You will need to draw up a custom shroud simulating the tail cone. There is a shroud generating program available here (paper cones transitions program):

http://www.rocketshoppe.com/tips.htm

"Sandpiper" was an Air Force project to develop a hybrid motor for the Jayhawk replacing the liquid hypergolic propellants with a solid fuel propellant and storable liquid oxidizer. Potentially much less problems compared to toxic, volatile hypergolics. Interesting stuff.

Anyway, I have this on my build pile as well.
Thank you! I hadn't remembered that Estes semi-scale kit (it looks like a BT-50-size near-duplicate of Centuri's semi-scale Jayhawk kit), but looking it up on the Ninfinger Productions website, I see why--it was only offered in 1983 and 1984, so it came and went quickly. A "hybrid" of this Estes kit and the Vashon/Estes Sandpiper kit (which was virtually the same diameter, 1.0" versus 0.976") would be a pretty accurate depiction, if it used Aerobotix's 3D printed BT-50S "canard-ed" nose cone (and the card stock tail cone from the Estes kit), and the Vashon/Estes kit's main wings and tip fins, and:

Such a model could depict either the Sandpiper or the AQM-37A by having either a single rocket exhaust orifice (Sandpiper) or the AQM-37A's two booster/sustainer rocket exhaust orifices (a removable-for-flight "display plate" would even allow either variant to be depicted). The Sandpiper kit illustrations in the Estes catalogs show it as being a yellowish green, but (guessing here, as I've never seen a color [or even black-and-white] photograph of a full-scale Sandpiper) I imagine the actual Sandpiper vehicles were the same bright orange or reddish-orange color as the AQM-37A vehicles.

blackshire 04-12-2018 11:46 PM

Quote:
Originally Posted by ghrocketman
The DANGER-factor is what makes hypergolic liquid propellants FUN !
Ironically, they're a fire hazard, but not an explosion hazard, because hypergolic fuel/oxidizer combinations can never mix together to form explosive mixtures (the Gemini spacecraft used ejection seats rather than an escape tower for this reason, because the ejection seats were lighter). Old films of Titan II failures (which are on YouTube, as are videos of Russian hypergolic-propellant vehicle failures) show this. Instead of a detonating fireball with a destructive shockwave (which kerolox, hydrolox, and solid rockets produce when they fail), Titan II, Proton, and other all-hypergolic rockets burst and then create a quick flash followed by a brief "exhaust streak," instead of a detonating fireball.


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