Polecat Aerospace 4" Black Brant III

A 54mm coupler will work even better than an actual motor, as it is a tighter fit than an actual motor casing.

AdAstraPerAspera said:

A 54mm coupler will work even better than an actual motor, as it is a tighter fit than an actual motor casing.

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That's good to know... I've been musing on the same problem. Thanks!

Alright guys, time for some quick advice.

1) I have a Top Flite 58" chute at the ready for main, but don't have a drogue. Open Rocket is suggesting that an 18" chute will give me about 65fps. Sound about right for a rocket this size? I have an 18" chute that I pulled off another kit that I'm pretty sure isn't thin-mil, and I'll probably use that for drogue. Is there anything I'm missing here?

2) I'm getting the black-powder blues. I went to a sporting store and found some Triple Se7en FFFg sized powder. Upon some research, it looks like it would be really, really preferrable to use actual black powder, for risk of the BP substitute not getting a full ignition during the ejection process. I haven't ground-tested yet because I was hoping to take another look for black powder. Where are you guys finding this stuff? Specialty ammo/reloading stores? Or am I reading into too much here and should just crack my can of Triple 7 open and commence ground testing?

My progress this past week consisted mainly of adding more red paint (saw some areas where the coverage was noticeably lighter and had to take care of that), and letting the rocket sit for several days while the paint cured. I got some black on the bottom centering ring, but wanted to let that cure for a while before installing the retainer. Finishing becomes quite the exercise in patience once the colder weather creeps in.

I bought my first can of FFFFg BP at Gander Mountain, but that was years back, about 2008. I still haven't used it all BTW. A lot of those stores don't carry it any longer because of the magazine requirements for storing it. The substitute powder they can leave on the shelves, but not the BP, so you do need to ask for it since they will usually leave it back in the Mag.

If you can't find it at a local gun shop, check for BlackPowder hunting/gun clubs in your area. You might ask at the Issac Walton League if you have one in your area. I have a friend that teaches conceal carry classes and is well connected with the local shooting folks. I just as him and he can get me a lbs. whenever.

Handeman said:

I bought my first can of FFFFg BP at Gander Mountain, but that was years back, about 2008. I still haven't used it all BTW. A lot of those stores don't carry it any longer because of the magazine requirements for storing it. The substitute powder they can leave on the shelves, but not the BP, so you do need to ask for it since they will usually leave it back in the Mag.

If you can't find it at a local gun shop, check for BlackPowder hunting/gun clubs in your area. You might ask at the Issac Walton League if you have one in your area. I have a friend that teaches conceal carry classes and is well connected with the local shooting folks. I just as him and he can get me a lbs. whenever.

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Here in the "People's Republic of New York," BP is barely available but you have to look nard to find it. I have found that gun stores in smaller towns that have room outside to store it legally are better places to go...but not in NY.

Have you tried any of these places:

https://local.biggamehunt.net/Black_Powder_Supply_Stores_Seattle_WA-p1712358-Seattle_WA.html


4Fg is the preferred for what we do, but 3Fg is more common and it will work, if you are at one TCR's launches I can loan you some, or even pick some up as long as our local dealer is still in business (he was talking about moving to Pahrump, NV last year when I last went in to visit).

Flyfalcons said:

Alright guys, time for some quick advice.

1) I have a Top Flite 58" chute at the ready for main, but don't have a drogue. Open Rocket is suggesting that an 18" chute will give me about 65fps. Sound about right for a rocket this size? I have an 18" chute that I pulled off another kit that I'm pretty sure isn't thin-mil, and I'll probably use that for drogue. Is there anything I'm missing here?

2) I'm getting the black-powder blues. I went to a sporting store and found some Triple Se7en FFFg sized powder. Upon some research, it looks like it would be really, really preferrable to use actual black powder, for risk of the BP substitute not getting a full ignition during the ejection process. I haven't ground-tested yet because I was hoping to take another look for black powder. Where are you guys finding this stuff? Specialty ammo/reloading stores? Or am I reading into too much here and should just crack my can of Triple 7 open and commence ground testing?

My progress this past week consisted mainly of adding more red paint (saw some areas where the coverage was noticeably lighter and had to take care of that), and letting the rocket sit for several days while the paint cured. I got some black on the bottom centering ring, but wanted to let that cure for a while before installing the retainer. Finishing becomes quite the exercise in patience once the colder weather creeps in.

Click to expand...

Regarding the drogue: Is the Cd set right for the chute in question? You're best bet is to find a descent chart for that particular chute. If not, err on the cautious side and use a low number like .6 or .7. In the end, since it's a drogue you have more leeway in size selection. 18" sounds about right though.

Regarding the black powder: Best place is a gun store. Ask for "4F Black Powder for muzzleloading, preferrably Goex" and they should be able to help. I can't speak to the availability in WA, but in PA it's readily available from most any gun store.

IF you use FFFg BP or a substitute, make sure that you ground test. You will need to contain it more than FFFFg black powder for it to burn properly. A 4-6" section of 1/2" copper tube with a end cap soldered on is a good way to do it. Ematch and powder go in the bottom and the rest of the tube gets stuffed with cellulose insulation ("dog barf") and taped over with masking tape.

Been a while since any updates but the holidays, young kids, and winter time here seems to have that effect. I have a source for real BP now and just need to catch them when they actually have the 4F powder in stock. They're only able to order 25 pounds of BP of all flavors at a time, so whatever 4F they do get in an order seems to go quick.

I got tired of looking at my rocket in just the paint, so I added my vinyl from Stickershock. It's their standard BBIII kit, not sure about the accuracy or directionality of the words and logos but it's also not something I'm bothered by. This is one colorful bird when complete and I really like how it looks.

I have a J270W for the cert flight and I'm hoping to make a launch in April for the cert attempt. Ejection charge testing will occur once I get a can of black powder, and I will be taking measures to protect the paint and decals during testing.

Very nice indeed Ryan!

Looks fantastic! Good luck in advance on the cert flight!

Okay, time to wrap up the build and review of this unique kit. As someone new to altimeter-controlled dual deployment and building a rocket of this size, there was a fairly steep learning curve involved. There were a few times where I was cursing Polecat's name, mostly during the bondo-sanding portion of the build. In the end though, this kit turned into a very cool rocket that you don't see modeled very often. The fiberglass-wrapped cardboard tubes are strong and light, and the finished weight of this rocket with everything installed including redundant altimeters is 7 pounds 3 ounces (minus motor). Because of the length of this design, there was no nose weight required to balance with the J270W, and in fact it is overstable at approximately 3 calibers. I wouldn't say the kit is perfect and I don't think there is such a thing, so I wanted to organize my thoughts about it into a few pros and cons:

PROS
At $139, a very reasonably priced kit for an 85" long, 4" diameter, fiberglass-wrapped design
The kit includes all hardware and two 12' nylon harnesses (which after bowing to peer pressure, I replaced with OneBadHawk)
Familiar materials are easy to work with and parts fit is good
Finished product looks fantastic
Fairly lightweight construction allows this kit to be flown on a variety of motors and helps keep impact damage on the fins to a minimum

CONS
Some of the price advantage was taken away after I purchased a tub of Bondo and an orbital sander to smooth the fiberglass on the tubes
The instructions contained numerous carry-overs from other Polecat kits, leading to some confusion on parts content
The box had a BBII painted on it! I thought I was buying a II. This was an accidental BBIII build!
I have seen numerous, numerous complaints on not being able to contact Polecat, and I faced the same frustration when calling them with a question on the build (despite leaving two messages, they never called me back)
Very minimal instruction related to setting up the avbay - without resources like TRF, I would have had a difficult time setting this rocket up properly

Now the big question.......would I do this again? Yes, absolutely I would! In fact, I have another Polecat kit eyed that I'm hoping to pick up from a vendor at a launch in a week. This will get tucked behind a couple current builds, but getting one straight from a vendor will probably be easier than trying to order through Polecat directly. Yes, that is a dig at the company itself; in this day and age of electronic communication, advertising, and exposure through social media, a company that has poor communications is not one that can remain truly successful. Company issues aside, their product is something that I like very much, and even though LOC just announced a very tempting 7.5" Patriot, I'm going to see about getting me another Polecat kit for my next big build.

Now, for the good stuff and conclusion of my contributions in the thread: The maiden launch and L2 cert attempt. It has been half a year since I put paint on this rocket, and I have ground my teeth through weather, scheduling, and other issues to finally get this thing in the air. So when all the stars aligned and facing a potentially windy weather forecast, I loaded up my car with rocket stuff and drove out to the Tri-Cities Rocketeers near Pasco, WA, where I took the L2 written and met with rharshberger to proceed with the certification attempt. This is how it went.

[video=youtube;_1YlAIbiR9I]https://www.youtube.com/watch?v=_1YlAIbiR9I[/video]

Congratulations! Beautiful rocket. Beautiful flight.

Cheers,
Michael

Congratulations on your L2, lovely build, great rocket and thanks for posting such a detailed summary review of the whole experience.