PDA

View Full Version : New Wildman 38mm BlackHawk prototype....first look !



blackjack2564
6th November 2010, 01:10 PM
Wildmans added a big brother to the BlackHawk series. Dual deploy, ready to eat 38mm motors for breakfast, and disappear in a nano-second if you blink.

Just in time for Thanksgiving holidays! You'll be really thankful if you get one,something to build after all that Turkey.

This 38mm Black Hawk is neither carbon nor G-12. Rather a special graphite loaded fiberglass spiral wound at different angles than normal G-12. Resulting in airframes stronger than G-12 but not as strong as carbon.

I call it "Carbonite"
It is a minimum diameter rocket

Make no bones about it. It is a blatant copy of the Mongoose 38, [tad bit shorter] but sells for 1/2 the cost. 125.00

Comes with :

G-10 fin alignment guides
3 Black graphite G-10 plate fins beveled
1 Carbonite 32in [ 81.28 centimeter fincan] black tube
1 Carbonite 16in [40.64 cent payload] black tube
1 6in [15.24 cent] coupler/av-bay
bulkplates [4] for av-bay
1in [2.54 cent] coupler to attach shock cord to.
Von Karmen black NC.
12ft [ 3.65 meters] kevlar shock cord 800lbs test 1/4 in shock cord [2 one for apogee.one for main]
30in [76.2 cent] premium Topflight chute

Pro-line black epoxy [same stuff is supplied in the Mongoose kits] 500 degree high temp for minimum diameter rockets. Not shown in photo.

This one weighed in at 1.85 [ 840 grams] loaded and ready for launch. Chute, shock cord altimeter[PerfectFlite] 9v battery and clear coated. It can handle ANY 38mm commercial length motor.

Overall length of BlackHawk 38 is 52 inches or 132 cent. making it one mean, lean, mach-busting machine! These are the raw tubes clear coated.

blackjack2564
6th November 2010, 01:43 PM
Some of you lucky enough to be at Red Glare or Mid West power got to see one firsthand. Never know what Tim's gonna pull out of the trailer or when!

I finished the proto just in time to fly it at MWP. Was going to test it on a wimpy little H-123, just to make sure everything worked correctly. [charges,vents,shearpins etc.]

But as luck would have it, my buddy Daryl from Wildman Kentucky was there. He stopped me from making this wimpy blunder in the nick of time.

Seeing the new Blackhawk 38, he immediately challenged me to a Drag race with his Mongoose 38.
Hmmmm, a chance to see how this beast would do against a carbon fiber speedster,something that was going to happen sooner or later anyhow.

Well you know the rule: if a Wildman brother throws down the challenge,ain't no back'n out. Like I'm going to turn down a chance to drag race?:D

And don't forget the other Wildman rule, something about sticking the biggest motor you can in the pipe that will fit.

So much for the wimpy test flight and working my way up with motors. Start right off the bat with a biggie in a drag race. Must be in the Blackhawks bloodline! I wouldn't have it any other way.

Soooo.....we rounded up 2 CTI blue streak J-595 6 grain XL's and it was game on. If you haven't tried a blue steak yet, DO IT,do it now, they are really something! [and they match my eyes, most of the time, Sunday morning they look more like the red lightning!]

BlackHawk 38 weighed 4.7 lbs on the pad.
Mongoose 38 weighed 4.3lbs on the pad. [6inches longer]

Button pushed and away they went in a blurrrrr...........
Thanks to Daveyfire we got a pic of the first flight. Thanks David, don't know how you do what you do, but you do!

The results speak for themselves, Mongoose was a tad faster off the rail,but when it was time to count the cards......

Blackhawk hit 12,188ft
Mongoose hit 11,001ft

Whoa! partners....we got us a winner here, er....Wildman does!
Just goes to show something I've been saying all along, carbon can be overkill for alot of things and fiberglass can do much more than given credit for.
Especially at less than HALF the price. Got ya thinking now, don't I!

Just one problem though. What to fly next to re-capture the thrill? I'm sure I'll think of something. [reminder to self:must look in Tim's & Dr. J's area 51]


On with the build!:pop::cheers:

blackjack2564
6th November 2010, 02:01 PM
First thing to be done is sand and fit the fin guides so the tube and fins slide in freely when it comes time to glue.

Crazy Jim tip:
Sand off the corners of guide so when tacking the fins on, the glue squishing out from underneath won't end up gluing the guides on the tube. Don't ask how I came up with this!

Pantherjon
7th November 2010, 03:53 PM
I would think sometime this week? The Darkstar Mini is already on the site..:)

blackjack2564
7th November 2010, 08:11 PM
Hi Jim, Any idea when these will be available ?

Right now, Just call in the order, you know me I'm always giving the forum guys first crack at stuff.

It takes a few days for Tim to get things on the web and announcement page.

The instructions are almost finished, and I will continue to post assembly here shortly

blackjack2564
10th November 2010, 05:44 PM
Ok then here ya go....instructions!



I measured 1.75in [ 45mm] from rear of tube and taped to mark for fin positions.

This does 2 things, gets the fins slightly more than the one caliper needed [from rear of tube]to allow the turbulence from the fins to return to laminar flow.

Protects them from landing damage.


Next mark all 3 fin positions.



Extend lines using your favorite method.

blackjack2564
10th November 2010, 05:51 PM
Measure and mark front for tape ring. [ I just used the fin, pure lazy]


Rough up the surface on each side of line with 60-80 grit sandpaper for fillet adhesion.

If you are clear coating, might want to tape off the tube so you don't get scratch marks all over the place. They are extremely hard to cover. If painting, not needed.

blackjack2564
10th November 2010, 06:15 PM
Fins come beveled, so you only need to sand the root for glue adhesion and fillets.

Fin guides are labeled with a "T" for top on one corner. I mention this due to the many inquiries I've had asking what it was.
It works best when oriented this way

Prep tube & guides by pre-fitting a fin in place to show where they should be located. I had to shim the tube a little with tape to get a snug fit, then taped guides in place.

n1lul
10th November 2010, 08:17 PM
Looks great! Are you useing the Feather weight Av bay or are you going to "roll your own" using the parts in the kit?

Now I need to replace my BH 24, unless I find it this month when I go to Price, AND get a BH38. and a Ultimate WILDMAN this spring. I have the sticker already, so I HAVE to get the rocket. Right?

I am glad I have a very understanding wife.

Rocketman248
10th November 2010, 08:30 PM
So many new rockets, so little time/money!

I hope you find your BH24, Ray. That was a sweet boost!

troj
11th November 2010, 02:10 AM
Tell Tim I wanna know when mine is gonna arrive -- I have 24, 29, and 54... There's a gap there that needs to be addressed!

-Kevin

blackjack2564
11th November 2010, 04:52 AM
Tell Tim I wanna know when mine is gonna arrive -- I have 24, 29, and 54... There's a gap there that needs to be addressed!

-Kevin


You can only have one...... IF.....you promise to keep the pointy end going UP!

TZ250
11th November 2010, 07:46 AM
Jim, thanks for the information and the build thread. What was the max. acceleration? What was the max. velocity?

A 38mm speedster would be perfect for me. My 54mm Kestrel is too much for Ohio and it will be a hassle to adapt it down to 38mm. Tim has already solved that problem for me. I just need one more Wildman rocket! :D

What did you use for a tracker in the small 38mm airframe?

What method of motor retention does it use? Friction? The fins are not through the wall, correct?

blackjack2564
11th November 2010, 02:05 PM
Looks great! Are you using the Feather weight Av bay or are you going to "roll your own" using the parts in the kit?

.

Did you have a tracker in it? If not you are a brave, brave fellow!

I used a sled from my NSL Thor which is 38mm. Barely can get the battery in. Perfect flight HiAl 45.

I would love to have the Raven setup and really need to get one. I get peppered with questions about them all the time. BUT I use a Mac and cannot program or download data.
[NO I am NOT going to run-any parallels type programs, I am computer illiterate and don't want to hear how easy it is to do this!]

Hopefully I can find a used or cheap windows unit to do this. My old one just died. Then I will invest in the raven and AV-bay.
For now 12,000+ feet is plenty with my old setup.

The sled from the mini Thor fit right in the 6in bay.

By the way..... Your wife is lucky you don't have a Ferrari sticker!

blackjack2564
11th November 2010, 02:14 PM
Jim, thanks for the information and the build thread. What was the max. acceleration? What was the max. velocity?

A 38mm speedster would be perfect for me. My 54mm Kestrel is too much for Ohio and it will be a hassle to adapt it down to 38mm. Tim has already solved that problem for me. I just need one more Wildman rocket! :D

What did you use for a tracker in the small 38mm airframe?

What method of motor retention does it use? Friction? The fins are not through the wall, correct?

The vel was Mach 1.65 if I remember right, but that was the other rocket [mongoose] He had a raven in his. I used a non data unit. We did fly the same motor.

Tracker was the the Communication Specialty unit [or rocket hunter as they used to be called]. It will fit in my 29mm Hawk, but you have to take the case off for that. These are the units Tim sells, transmitter is around 100 bucks.

Motor was held in by good old friction fit, with one wrap of duct taped around the outside of motor closure and rear airframe.

The fins ARE surface mount, kit comes with G-10 alignment guides and the black 500 high temp epoxy to mount them with.
Fins ARE beveled as supplied in kit.
This is a lot of high performance rocket for the money.

troj
11th November 2010, 03:10 PM
You can only have one...... IF.....you promise to keep the pointy end going UP!

How 'bout one comes my way and we plan a drag race for LDRS?

-Kevin

Mindcrime
11th November 2010, 04:28 PM
First one back in the ground wins right?

troj
11th November 2010, 04:34 PM
First one back in the ground wins right?

:bangbang:

Geeze, a guy buries one teensy little rocket.... :p

-Kevin

daveyfire
11th November 2010, 05:00 PM
This is a lot of high performance rocket for the money.

Looks just like a MG, flies better than one for half the price. What more could you want? Glad I could be of help with the launch pic... it's a little blurry cause those things were GONE :cool:

When does the 54 come out? I bet it'll compete favorably with the KestreL...

blackjack2564
11th November 2010, 05:02 PM
First one back in the ground wins right?

How about....First one back ON the ground...LOL

Black epoxy is mixed 5.5 resin to 1 part hardener. This stuff is pretty gooey and a tad hard to work with if you've never used it before. I use a scale to weigh it. It does flow out beautifully however.
For tacking the fins, I use JB Weld, either will work fine. I just did not want to measure and mix such a small amount of the high temp stuff.

Butter the root edge of fin to tack. If it's your first time with minimum diameter or you're a tad uncomfortable doing all 3 at once, just do 1 at a time. Building should be fun, not stressful & aggravating. JB is so easy to mix small amounts.

blackjack2564
11th November 2010, 05:16 PM
I recommend a dry run with all 3 fins and no glue to find any pitfalls for the first timer.
You may wish to re-adjust guide placement for ease of slipping the fins in place. It helps to number each fin & corresponding slot. They always seem to fit better this way when it's time to glue.
anyhow......

Take fin with thin bead of epoxy on bottom [buttered root edge] slip it into the front guide at a down angle, going past the rear guide. Don't let fin touch tube yet!

With one hand holding fin in front of guide, use other to grab fin between guides. Slide fin through rear guide and position above the line.


Keep front of fin up and lower back onto line, and into proper position.

blackjack2564
11th November 2010, 05:25 PM
Working from rear to front, push fin down into position.
Not to hard but firmly, you do not want to push out all the epoxy from under the fin.

Rotate guide and repeat for 2nd and 3rd fins.

Or just do one. Set aside to cure.


My guide held the fins a tad loosely so I improvised by using pencils to wedge them in place while curing so they could not move.

A little more tape to hold things proper, and all was in happy land for the night.

Mad Bomber F/X
12th January 2011, 03:17 AM
Just trying to finish up my Blackhawk 38 build. Had a brain fart while drilling all the holes. I used the half hole method for my wires. I added 2 1/8" vent holes for the av bay. When all was said and done I noticed that one rivet was in line and about 1/2" above the wire hole. The 2 1/8" av bay vents are fine, nothing above them. I was wondering if the rivet above the wire hole for the av bay will cause any problems with my MissleWorks alt? Should I move the wire hole so it isn't in line with the rivet, our will it be OK since I have 2 other 1/8" vent holes?

blackjack2564
12th January 2011, 05:22 AM
Nah, you're alright. I almost did the same thing myself.

Just remember when flying subsonic to tape wire to the payload. I goofed once & taped them to fincan, not very pretty when apogee comes! LOL

I tuck them inside for mach.

What you using in the av-bay? [altimeter set up] Don't forget to post some pics of your project and follow up with some flight reports please.

Rocketman248
12th January 2011, 05:37 AM
Just remember when flying subsonic to tape wire to the payload. I goofed once & taped them to fincan, not very pretty when apogee comes! LOL

Yup, I've done that before! :rolleyes: I got lucky and it missed the runway by less than 6 inches. :eek:

GRIFFIN
13th January 2011, 04:32 AM
Nah, you're alright. I almost did the same thing myself.

Just remember when flying subsonic to tape wire to the payload. I goofed once & taped them to fincan, not very pretty when apogee comes! LOL

I tuck them inside for mach.

What you using in the av-bay? [altimeter set up] Don't forget to post some pics of your project and follow up with some flight reports please.

Since we are on the topic of "brain farts,drills and av bays" I also am building my BH38 and made the (half hole) hole in the av bay 1/4" instead of 5/32" I assume this is also no big deal. Should I skip adding any other "vent holes" in the av bay since I made the one too large??
Thanks in advance Jim

Jason

Pantherjon
13th January 2011, 05:10 AM
I would still put 2 more vent holes in(1/8")..Even though you made the 'half hole' bigger then you intended you will find it easier to fish your power wire through(if you do the 'twist and tape' method)..

blackjack2564
13th January 2011, 07:07 AM
Since we are on the topic of "brain farts,drills and av bays" I also am building my BH38 and made the (half hole) hole in the av bay 1/4" instead of 5/32" I assume this is also no big deal. Should I skip adding any other "vent holes" in the av bay since I made the one too large??
Thanks in advance Jim

Jason


Ya should be OK, but then I'm SURE somebody will eventually disagree. I stuck vent holes in a NC for a bay installed there once. It worked just fine, even though I was told no way.

Hey... you're a Wildman ain't ya?!!! Just fly it!


I would add 2 tiny others ones, just so a gust of wind doesn't "trick" the alt if it's baro. [ I used 3/32]

Don't forget to set you "mach" delays on this one guys! [if using baro units for apogee] You most definitely will need to.

rfjustin
13th January 2011, 04:37 PM
Should I skip adding any other "vent holes" in the av bay since I made the one too large??

IMO, yes. Leave the single .250" hole there to vent the bay. More holes are not needed.



Justin

cmcain
14th January 2011, 05:09 AM
what motors have people been flying their blackhawk 38s on and what kind of altitudes have been achieved? has anybody flown one on an at j510w yet?

blackjack2564
22nd February 2013, 03:13 AM
I'm resurrecting this thread.
Due to a resurgence in the Blackhawk 38:

There have been numerous questions asked about this kit, so I searched back & found this.
Lo & Behold I never finished it! [Here anyways....I did the main build on the Australian Rocketry Forum for my mates down under]

So tomorrow I'll get out my BH 38 take some more pictures, cipher through the ones I have & finish it up, hopefully answering many of your questions along the way.
It's been through hell & back with a good bit of info logged into my flight book.

One of my all time favorite rockets & hopefully soon to be one of yours. Hard to beat for 125 bucks!
It's survived many drag races,[including the infamous first Pyrate drag race] lost in a tree, lost in a field and run over by a tractor towing discs, re-finished & vinyled several times to boot.

So start thinking of any question/problems you may have & we'll solve them together!

cwbullet
22nd February 2013, 03:21 AM
Cool. I have been following the thread. I may have to suggest Bridgett start on this one without me.

powderskierman
22nd February 2013, 04:40 AM
Damn, I just finished mine. Can't wait to see how she compares. CJ, will you be talking about trackers? I sure hope so, I'm having a hard time figuring that out. I want to use a GPS tracker but don't think it's going to fit.

stealth6
22nd February 2013, 04:48 AM
Cool. I'm in the middle of a scratch built 38mm project. It's my first minimum diameter, and will fly WAY higher than anything I've built so far. I'm looking forward to picking up a handy tip or two from this thread that may apply to my own. I'll be watching/following along.

s6

blackjack2564
22nd February 2013, 04:57 AM
Damn, I just finished mine. Can't wait to see how she compares. CJ, will you be talking about trackers? I sure hope so, I'm having a hard time figuring that out. I want to use a GPS tracker but don't think it's going to fit.

Yes I will cover that. I don't have a GPS as of yet.[waiting for the MissleWorks version] but if you have the dimensions of what you wish to use, I'm sure we can figure it out in a simplistic manner.

powderskierman
22nd February 2013, 05:08 AM
Yes I will cover that. I don't have a GPS as of yet.[waiting for the MissleWorks version] but if you have the dimensions of what you wish to use, I'm sure we can figure it out in a simplistic manner.

I plan on waiting for the missleworks also, any idea when it might be available? I was hoping to go big at spring Red Glare so I'll need something. Before I heard about the missle works, I was thinking BRB 900.
Stoked to have you doing this thread. Your 3" Darkstar thread was great!!

KenRico
22nd February 2013, 07:24 AM
I am waiting for the Missileworks too !

Kenny

HOBOjr
22nd February 2013, 04:26 PM
I'm also just finishing mine, with a few mods,and will be interested in seeing you complete this thread.
I have a question that might have been answered already but I can't seem to find it. In Open Rocket
to get a good stability margin it seems that you have to add a lot of nose weight. Have you added
weight and how much?

Darrel

blackjack2564
22nd February 2013, 05:19 PM
I'm also just finishing mine, with a few mods,and will be interested in seeing you complete this thread.
I have a question that might have been answered already but I can't seem to find it. In Open Rocket
to get a good stability margin it seems that you have to add a lot of nose weight. Have you added
weight and how much?

Darrel

NO nose weight needed. Nada...None for any motor. Mine has flown on 29mm 180 case motors [H-165..H-128] 29mm 240 motors [H-180 ..H-210..H-220] In 38mm loads in the 240 case....360...480....600....720 cases In CTI every case from 2grain to 6xl.

There are NO stability issues.

There may be issues with the particular sim file you have regarding the weights of individual components. Did you draw this file yourself...weighing the parts...or is it someone elses?

Before this is over I will find mine, or draw one that's accurate.

blackjack2564
22nd February 2013, 06:47 PM
Using a [1in.diameter] section of PVC pipe for my tool to pull out fillets, I first use it as the guide for placement of masking tape.
If done correctly the edge of the tool will just hit edge of tape when smoothing the fillets, keeping all the excess on the tape where it can easily be removed.
Leaving little or none to be sanded when the tape is removed.

Lay the tool in the V-groove and mark where edge touches fin. Mark at rear and front of fin.

119060


Mark where tool edge hits tube. Mark at front and rear of tube.

119058


Lay tape ,butted to marks front to back. check alignment with tool and adjust tape. The closer to where the tool hits tube and fin, the less sanding will be needed to attain great fillets!

119059

Since I originally came up with this method 3yrs ago, I have refined it to using the PVC smoothing tool as the guide. Coat the edge with Magic Marker119056 and rub back & forth leaving marks you place tape on. It will take several "coatings" & rubbing in the V-groove while "rolling" the PVC pipe section to accomplish good marks.119057

blackjack2564
22nd February 2013, 07:01 PM
I used 15 grams of resin to 3.5 of hardener for each set of fillets [2 fins] .
Spreading the gooey epoxy into the V-groove as best as I could.
I knew better, thinking I could beat the odds, but as you can see by looking at my hands, I should of used nitrile gloves.

119061


Level out the epoxy as best you can. Makes it easier to pull the fillet later.

119062


After dipping the tool in alcohol, smoothed the fillets. You can see they are pretty clean, all excess on the tape. I got a good close edge with no lip.

119063

blackjack2564
22nd February 2013, 07:07 PM
Different views so you can get a better idea of the fillet radius I was trying to attain.

119069

After doing some research, discovered a paper study done by NASA somewhere stating the ideal radius for fillets was 4-6 % of the root length of the fin. That's why I use the 1in diam. tool.[ I stayed at a Holiday Inn last night, maybe I dreamt that!]

119068

They look much larger than they really are.

119067

Viperfixr
23rd February 2013, 08:50 AM
Is there a Blackhawk 54 in the works...maybe? Something with a slotted tube for a little more adhesion surface area with the fins? Long enough to take a 54/2560 or 6XL case in the lower airframe?

blackjack2564
24th February 2013, 06:20 AM
Is there a Blackhawk 54 in the works...maybe? Something with a slotted tube for a little more adhesion surface area with the fins? Long enough to take a 54/2560 or 6XL case in the lower airframe?

Yes ... Wildman is currently working on "project X" in his "Area 51" Yes it will handle Loooong motors.

As my SpaceCowboy 54 brought some new technology to the hobbyist for the first time ever..... Wildman has been working quietly on his new 54mm minimum to plug the gap in the BlackHawk series. Needless to say "radical" barely describes this thing & takes it whole next step forward....scratch that.....leaps & bounds forward. I am VERY excited about this new concept borrowed from the Aero-Space industry. New production methods are in the works as well as some other secret sauce technologies for putting the beast together.

That's all I can say about it, so don't bother with the PM's, e-mails, or asking me at a launch....I won't even acknowledge or reply to any question....period

.................................................. .................................................. ..........
Nose cone for holding stuff:

I'm leaving it open for a variety of uses, remember this rocket is "Carbonite" NOT Carbon Fiber, so it's transparent for radio signals.

Cut a small section of Kevlar off the supplied shock cord to make an attachment point loop on the nose cone.
Tacked it on both sides with CA. [ I used a ring supplied with AT single use motors that's glued on as a thrust ring.] Seen here from my old files used in an adapter application for a thrust ring also. It happens to fit perfectly inside the NC & lets you put a nice fillet around it holding shock cord loop in place119351 If you don't have any laying around cut off a section of any 29mm tube.

Then cut small sections of cardboard tube to compress and hold the tails in place while applying your favorite epoxy.....JB weld. Just so happens the spacers will accept a section of 29mm tubing should i want to place a tracker or other electronics in the NC and have them removable.119352

So when your done you can make a 29mm tube/av-bay/tracker bay that slides right into place!

blackjack2564
24th February 2013, 06:37 AM
Recovery gear Y-harness:
Some of you may forgo this and use a threaded plugged closure with an eye-bolt in it for recovery attachment. I did this:


Cut loop of Kevlar to make recovery harness.
Epoxy into the inside of the 1in. small coupler, [that will be slid inside the fincan when finished]
I actually used a small slice of another coupler that fit inside this one to "sandwich" the Kevlar.[seen in upper left of photo, just sliced a bit out so I could compress it, to make it fit inside the coupler.] This is basically the same technique I used in the NC. No way the Kevlar can come off!

119359


Proper placement of recovery harness is just above the largest motor case you will fly/fit into the rocket.
Here you see the 6grain XL CTI and the AT 1380? [someone correct me if I did not remember] Lined up with rear of rocket to see how far north the coupler must go

119360


Close up reveals the magic number is [24in.] for the edge of coupler. I will use rivets to hold in the assembly, but not drilled through the coupler, too hard to locate them. Drilled above the coupler
I want the coupler removable to clean and also bang out motors [friction fitted] with a stick.
Insert the assembly & push past the rivet holes.
Insert rivets [2 opposite side from one another.... 180 degrees apart]
Pull assembly up tight to rivet so there is no slack.

Edit: since I built this 3 yrs ago, I have been using a more aero-dynamic approach. Instead of rivets which protrude into the airflow I would use #8 set screws, mounted flush with airframe, like method used in the SC 54 av-bay.

119361


Yeah the hole you see is a Snafu... I forgot about the Big AT case and began to drill holes for the CTI. Then had to move them. But hey....better me than you!

Now you have a nice clean recovery attachment point.

blackjack2564
24th February 2013, 06:50 AM
This is what it would look like in proper position internally, rivet in place. 2 rivets 180 degrees opposite on airframe.
NOTE: the rivets do NOT go through the coupler assembly, but are in there, so when the assembly is in place, it butts up to them. I just thought if I drilled into the coupler also, it would be miserable trying to align the holes for removal/replacement.

I'm sure the altitude junkies will use glue in technique, or flush mount screws of some type aero-dynamic trickery to squeeze out the last bit of performance.
I for one would like to see any tricks you use.
Edit: [of course now I use flush mounted set screws #8]

119373

There is a 1/8 pressure relief hole [for airframe to bleed off during ascent] drilled 1/2 between top of motor and bottom of av-bay [when installed in fincan]

I also put another smaller one down low[opposite side of airframe] for when I fly small motors to avert the possibility of the shock cord and nomex from blocking one of the holes.

HOBOjr
25th February 2013, 12:51 AM
Thanks Jim for the info. I used a sim file from another build here on TRF,
but I adjusted all the weights and dimensions to my kit parts and mods.
I'll go back and start a new file and see if that makes a difference.

Darrel

blackjack2564
2nd March 2013, 07:18 AM
Here's where all the fun begins, the av-bay:

For the Av-bay I used 6-32 threaded rod and eyebolts [welded shut]..... anything larger i would not have been able to fit my altimeter in. It IS that tight!

120169



After mounting all hardware, ground off excess to get more room. The sled fits on bottom rod. Had to tape battery in. Not enough room to get a wire tie around the battery in circumference or sled would not fit!

120170


Very simple sled,just bolt on altimeter [and a terminal block for Adept 22 to simply hook up, more on that later. One pic shows a PerfectFlite HiAlt 45, which is same size as Stratologger, other the Adept 22.

120175120176


But to utilize your space to the max, orient the sled NOT between the tie rods horizontally with a tube that fits over both, but rather vertically, so the tie rods fit above & below the sled. Sled is cut to fit below center line of av-bay, & snug enough that it can't move back & forth. Essentially "clamped"in place by the BP's on each end.
120178


Now there is plenty of room for electronics. Pic is another bay, but set up the same. Sled is used in both.

blackjack2564
2nd March 2013, 07:58 AM
Here are the Sim files for my rocket.

I don't draw all the parts, especially av-bay, BP's e-bolts, rods, etc. But I do weight the assembled bay with battery, sled, altimeter, rods etc. already installed for flight, Same for chute, nomex and shock cords, they just go in under chute weight. Even the fillets are in there. I weight the fincan before & after the fillets are done to get an exact weight.
So the total is correct and placed where it belongs.

The OR version has many flight sims in it, which compare very well with actual flights some are over, some under. That could be weather conditions ...temp, wind,location, etc.

The rocksim conversion from OR doesn't save the flights for some reason.

lawndartman
2nd March 2013, 09:29 PM
Jim,
What a wonderful thread. Great tips. I picked up one of these kits last year. I will review it carfully be for I start. SWEET!!! Tim Thomas L3

tstone
3rd March 2013, 04:33 PM
I 120365120364

I placed the front rail button just below the shock cord coupler mount to keep it from sliding down.
My fin fillets looked great like Crazy Jims' after pulling the Proline 4500 resin, but not perfect. After sanding them the
resin lost that sweet deep black color & were an ugly , sandy grey color, I carefully masked around the sanded
epoxy fillets & gave them a squirt of black paint before clear coating the bird.
The results speak for themselves.
Hats off to Wildman Tim for providing a great kit & an outstanding value.

Tim Stone, Northern Illinois
Going for L3 when my last kid is outta med school!

Buckeye
11th November 2013, 01:04 PM
Sorry to dig this one up again, but it is a great thread. So, in Post#2, is this rocket flown off a rail or tower?

blackjack2564
11th November 2013, 09:14 PM
Flown off a 1010 rail in 2010! Still flying.

Buckeye
12th November 2013, 04:14 AM
Thanks.

The reason I ask is that I have been simulating the BH38 in RasAero and get nowhere near 12k feet in your configuration. Only ~9000 ft with rail buttons. Take them off and the simulation says ~12000 ft. 3000' (33%) due to rail buttons? I don't think so.