# Sport Scale Terrier/Sandhawk

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#### eugenefl

##### Well-Known Member
Well, after being inspired by Jason Toft's impressive gap-staged Terrier/Sandhawk, I thought I'd build me a smaller scale to try my hand at gap-staging. I figure what a better way to gap stage than with a Terrier/Sandhawk. It's a great looking rocket! Don't ask me for measurements and such because I didn't stress over those details hence "sport-scale." How'd I get me fin pattern you ask? Simple - I found the coolest looking T/S via Google images and traced the fin patterns.

Here are some details:

CONSTRUCTION:

BT50 based airframe. (Both Terrier booster and Sandhawk rocket.) I suppose down the road I could build a BT55 Terrier booster and make a 4X13mm motor mount cluster.

BT50 Alpha nosecone.

PROPULSION:

24mm minimum diameter MMT in the Terrier booster.

18mm MMT in the Sandhawk.

Motor retention will be friction fit for both parts of the rocket. The total gap between the top of the Terrier motor and the nozzle of the Sandhawk motor should be no more than 5.75".

RECOVERY:

Terrier booster - tumble. (How else can I recover it? )

Sandhawk - metallic mylar streamer (when in 2-stage flight), 12" nylon chute for low A-C flights. Kevlar line for shockcord.

GUIDANCE:

3/16" Launch Lugs mounted on 1/16" balsa stand-offs.

OTHER NOTES:

I am hoping to fly it for the first time next weekend (Dec. 13). The first flight will be on either a C6-0 (with 18/24 adapter and depending on finished weight) or a C11-0 to an A8-5. I've heard that venting is necessary for gap staged rockets. Given the pressurized fit, I can see that any excess pressure would separate the two before the upper stage lit. If anyone has any input on what sized holes and how many I should make feel free to submit your suggestion.

Thanks! Enjoy!

...and they say that LPR isn't all that fun. Pssssh...this is gonna be cool!...and nervewrecking too!

#### eugenefl

##### Well-Known Member
I guess I should post a pic or two before the "Italian mob" hunts me down!

First pic is of the fins being filleted. I didn't do all that much photo documentation on this one, so you'll have to enjoy what pictures I did take.

#### eugenefl

##### Well-Known Member
Here it is getting fillets. Picture taken from the aft perspective.

#### eugenefl

##### Well-Known Member
Here is a picture of the launch lugs being mounted. HINT: launch lugs mounted on stand-offs will save your finished from dirty launch rods.

#### eugenefl

##### Well-Known Member
Aren't pictures great? Here's a view of the two sections separated. Both lugs are attached.

#### n3tjm

##### Papa Elf
Looking real good bro

#### Rocketmaniac

##### Well-Known Member
Eugene, you have another great looking rocket.........

#### arthur dent

##### Well-Known Member
Thats a fantastic rocket.......whats that yellow tool on your workdesk???
P.s. who says TRF aint fun

#### Rocketmaniac

##### Well-Known Member
Originally posted by arthur dent
whats that yellow tool on your workdesk???

That looks like one of the pieces from the Estes Fin marking kit????

#### eugenefl

##### Well-Known Member
Originally posted by arthur dent
Thats a fantastic rocket.......whats that yellow tool on your workdesk???
P.s. who says TRF aint fun
I personally believe the Fin Marking Guide is one of the most overlooked tools in the rocketeer's box. I personally never looked into it until Jason (jetra2) showed me his. This is a FANTASTIC tool! It's the <a href="https://www.a2zhobbies.com/Estes/Rocket_Accessories/EST-2227.html">Estes Fin Marking Guide</a> and only about $5.50-$7 depending on where you buy it. Throw away all of your rulers because this is the perfect tool for the model rocketeer. It is incredibly versital in that it allows you to draw any type of mark on the rocket perfectly. Need a straight line from top to bottom? The 90deg. wedge/angle on the tool places the body tube perfectly parallel to the edge of the ruler. The tool also comes with two yellow "discs" that are actually templates for fin marking. With this tool, there's no need to fuss with paper wrap fin marking guides! On the ruler portion, there's a unique slider. Tired of holding a ruler steady while you mark a certain length from the end of the body tube? Well, set your slider to the desired length and voila - you have the same distance marked all the way around! Ever have to draw a perfect tube cutting line around the outside of the body tube? With this tool you put your pencil in the holder (tube looking thingy that extends out of the tool), set your length with the slider, and rotate your tube. BAM! A perfect line is drawn all the way around. This tool has so many uses it's not even funny. It's heaven-sent for the low power rocketeer. I would seriously recommend this product for ANYONE. Makes a great stocking stuffer too!

Dang, looks like I just created an EMRR review. I couldn't seem to find one there.

#### Zippy

##### Well-Known Member
Eugene is right about the fin marking guide, I love mine and use it constantly. I just wish it were a lot longer.

Zippy

#### arthur dent

##### Well-Known Member
It certainly looks like eugenefl has used the fin marking guide to full effect now all i've got to do is find a U.K. supplier.It will be worth getting one just for making cutting lines

#### eugenefl

##### Well-Known Member
It flew!...and it flew great! I finally broke out the SS T/S and flew it at the SEARS572 Tour de Deuce launch this past weekend. I decided that for its first flight I'd go with a C11-0/A8-5 combination just to guage altitude and see how cleanly the gap stage would be. Folks, I don't know what the C11-0 burn time is, but the rocket *maybe* went 125ft when I heard it "pop" stage the Sandhawk. This rocket isn't even all that heavy! The A8 then took it another 500ft or so. I'm looking forward to a nice D12/B6-6 flight. I think I just may at our next club launch on the 21st (of Feb).

Now I just have to go paint it!

After a request from our very own revkeith, I dug around my build box and found the fin templates used for this rocket. Attached you'll find a direct scan.

I also have some other pertinent info regarding the rocket itself.

Here are the specs:

Terrier booster - BT50 dia., 8" length, 24mm minimum dia. MMT w/ Engine Block (could also make it an 18mm MMT) friction fit

Sandhawk - BT50 dia., 16" length, 18mm MMT w/ Engine Block w/ friction fit, Estes Alpha BT50 nosecone.

#### RevKeith

##### Well-Known Member
Thank you, Thank you, Thank you! After seeing the SS T/S last Saturday I just had to make one of my own. It took off like a bat out of a bad place. Eugenefl, I hope mine looks and performs as good as yours.

Keith

#### Silverleaf

##### Well-Known Member
Folks, I don't know what the C11-0 burn time is, but the rocket *maybe* went 125ft when I heard it "pop" stage the Sandhawk
Ya know, for a small field, this combination would be ideal to show new rocketeers how a multi stage rocket works. Plus nothing gets me more than seeing a booster stage drop and the upper stage do a roadrunner impression.

Now if I can only figure out how to incorporate a BEEP-BEEP sound at seperation..*mua-hahaha*

#### eugenefl

##### Well-Known Member
I finally got around to painting this one! Although I didn't spend a great deal of time on detail (I figure the risk of losing it is high), I think it still came out looking pretty cool. Flights on C11-0s to A8-5s might be the norm for this bird. It's kinda grown on me and I'd hate to lose it. Flight #2 will probably take place on the 21st at our monthly meet. Maybe next time out I can produce a flight pic.

Enjoy!

#### RevKeith

##### Well-Known Member
Here's my T/S naked. Waiting for good weather to prime and paint. I like this rocket!

Keith

#### eugenefl

##### Well-Known Member
Originally posted by revkeith
Here's my T/S naked. Waiting for good weather to prime and paint. I like this rocket!

Keith
Looking good Keith! Wow, I kinda got the goosebumps seeing another "clone" of my design out there!

I may have forgotten to mention this early on, but make sure you drill 2 - 1/8" vent holes opposite of each other just underneath the staging coupler to allow venting. I may actually end up enlargening to 3/16" holes, but another flight should determine whether or not I go that route. It just seems like there was an uncomfortably loud "pop" when the C11-0 staged to the A8.

#### extremevelocity

##### Well-Known Member
Hi eugenefl I can't see the attachment for the fins?
Would love to build one myself.
I'm working on a staged rocket and I think a 2 stager is plenty good.
It looks great very nicely done.
I can vouch for the fin marking guide myself,it's a great tool.

UK let me know if you can find a supplier ASAP,my mother in law is
flying over to London this coming week
I can always help you out by getting one and have it brought over the pond
Mike

#### eugenefl

##### Well-Known Member
Originally posted by extremevelocity
Hi eugenefl I can't see the attachment for the fins?
Would love to build one myself.
I'm working on a staged rocket and I think a 2 stager is plenty good.
It looks great very nicely done.
I can vouch for the fin marking guide myself,it's a great tool.

UK let me know if you can find a supplier ASAP,my mother in law is
flying over to London this coming week
I can always help you out by getting one and have it brought over the pond
Mike
Oops! Sorry about the fin attachment post. I was editing that response and accidentally deleted the attachment. That'd be really cool to see yet another T/S like mine. Let me know if you need any assistance.

Hmm, there's interest in this rocket. Perhaps it makes for a great FlisKits DOM entry!

#### extremevelocity

##### Well-Known Member
Well to be totally honest with you,I have looked at the rocket before and I really liked the looks of it.
I wasn't sure how difficult it would be to build and ended up putting the idea to the side.

I have a 3 stage Comanche I started to build before but when looking closer at it,I realised the fins where not straight.
I zipped down to my local hobby shop and had a Estees fin alignment guide ordered in for me.
The Comanche is neat but I really don't like the butt staging design on it.Add the cost for a 3 stage launch and the likelihood of loosing it.I tend to spend a fair amount of time prepping and painting when I build something.
So your design is Superior in my opinion
I read somewhere that you can reach altitudes very close to a 3 stager with a well built 2 stage design.
I will post some pics as soon as it's ready.
Yes you should definetely enter it with Fliskit imo
Thanx a bunch.
Mike

#### slim_t

##### Well-Known Member
Looks great Eugene.
Yours too Keith.
Guess I'm going to have to build one of these too. I haven't built a gap stage rocket yet, and this one seems a good one to start with. I just have to decide if I want to build this one or one like Jason's. Maybe both, but which one first? Hmmmm.

Eugene, what is that on your computer in the pic?
I think I'd like to go with the larger sized Terrier booster. Jimz has plans for the Sandhawk, but I couldn't find the Terrier.
Anyone have the dimensions?

Tim

#### Silverleaf

##### Well-Known Member
From ROTW - scale dimensions of the Terrier-Sandhawk combo at 1/80th scale

#### Silverleaf

##### Well-Known Member
Detail of the lettering - which is in red on the Terrier itself

#### eugenefl

##### Well-Known Member
Originally posted by slim_t
Looks great Eugene.

Eugene, what is that on your computer in the pic?

Tim
Thanks for the compliment!

Tim, that's the Estes Pro Series Terrier/Sandhawk that used to be produced back in the 90s. It's too bad it's not around anymore.

#### rock2p

##### Well-Known Member
Eugene,

I remember seeing this "rock" over at your place during the construction stages but I had not seen it painted yet.

Looks Great!

but how does it look under a microsocpe he,he

#### slim_t

##### Well-Known Member
Thanks Silverleaf. That should do just fine.

Tim

#### Micromeister

##### Micro Craftman/ClusterNut
TRF Supporter
Very Kewl Eugene! Great looking model,

#### eugenefl

##### Well-Known Member
Originally posted by rock2p
Eugene,

I remember seeing this "rock" over at your place during the construction stages but I had not seen it painted yet.

Looks Great!

but how does it look under a microsocpe he,he
Thanks for the compliments guys. This was a fun little build. Rock, you'll get to see it fly this weekend. Just cross your fingers for no wind. Even if there is some, it will be a repeat of the Alabama launch. I just REALLY want to see it go on a D12 to a B6-6!