Quantcast

MAC Performance 4" Blackfly Build - TRA Level 1 Attempt

The Rocketry Forum

Help Support The Rocketry Forum:

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
Hello!! New member to the forum. Getting back into rocketry after a long hiatus with a Level 1 Cert Attempt.
My goal date is a certification attempt on December 19th (contingent on weather, building, etc.) , with a 1G 54mm CTI I218.
I chose to build a MAC Performance 4" Blackfly, with the following component specs:
  • Wildman 4" 6:1 Nosecone
  • 7" x 54mm avionics bay in Nosecone
  • Eggtimer TRS GPS Tracker/Flight Computer, 900MHz (No electronic deploy, just curious on collecting flight dynamic data, and using for locating)
  • Eggfinder LCD Rx w/ LCD-GPS and Bluetooth
  • 54mm MMT, with 2G CTI 54MM kit and spacer
  • JollyLogic Chute Release
  • 4ft Rocketman parachute, am thinking of switching this out for a 5ft, considering I am using a JLCR
  • Aero Pack Retainer
I've already made some progress on the kit build, and so far, going well.


4 days after ordering, and speaking with Mike (great customer service btw! has been very helpful in guiding on this kit), I received this package:
IMG_20201123_123118.jpg
IMG_20201123_123216.jpg
IMG_20201123_123324.jpg




Dry fitting the parts, the build quality of this kit is clear. The tolerances are very tight, and the canvas airframe is fantastic. My how things have changed in a decade. The cat took interest, too.

IMG_20201123_153708.jpg


Started with assembly of the motor mount and recovery harness attachment point, along with the avionics bay. I am going to pause the avionics bay assembly at this point until I finish building the Eggfinder Tx, and fit an antenna that will protrude slightly through the top bulkhead into the nosecone. I am going to draw up a sled that bolts into the threaded cap of the avionics bay to hold a LiPo battery and the Eggfinder board.

I've calculated the inside volume of the wildman nosecone by approximating the avionics as a cylinder, and the portion of the nosecone after the bay as a cone, and subtracting the volume of the tip. With that volume (~145 in^3), I calculate that I need 3x 3/16" vent holes, using the relationship: Vent Area = ((Volume) / 100 in^3) * .05 = .073 in^2.

Open question, I'd love some input on this if anyone has thoughts. Assuming that I want the vent holes for the barometer on the Eggfinder as far away from the curve of the nose cone, and along the straight edge of the airframe's cylinder shape, so that I minimize airflow disturbances and am sampling from a smooth laminar airflow, I am thinking I will place these three 3/16" holes about 2" below the nosecone, in the airframe and through the coupler.
Obviously, they will need to line up for flight, but that won't be a problem because I am going to use a single shear pin. I can place the 3 vent holes and the threaded shear pin hole so everything lines up nicely.
Again, I am not using the flight computer for any barometric triggered recover events on this flight. I would like barometric data as clean as possible though, just to nerd out on afterwards.
Thoughts or input on hole placement? Is my above thinking reasonable?

One consideration, I may bolt two ejection charge canisters on the bottom CR of the avionics bay, if there is room. I haven't thought this through or made any measurements to see if it is even possible, but I'd love to have future electronic deployment capability for some high altitude flights and let this thing rip on a K or an L motor. I've already done a Rocksim of the largest L that CTI makes I could fit in this thing, and CG checks out and the rocket is still stable, thanks to the Wildman nosecone and the mass of the avionics. What (if any) are the general best practices for mounting deployment canisters on the bottom of a nosecone?

IMG_20201123_231919.jpg
IMG_20201124_220344.jpg



Rail buttons were a snap to mount. I used an Al angle iron to get a straight line along the chord of the airframe. Then crafted two, 1" x 1" x .25" Pine wood blocks, and Dremel tooled a curve that matches the ID of the airframe, than drilled out holes for two Tee nuts. . I was careful to keep epoxy out of the threads. This ended up turning out perfectly, and I now have removeable rail buttons.

IMG_20201124_221908.jpg
IMG_20201124_225623.jpg
IMG_20201124_225630.jpg
 

Attachments

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
Today, I'm setting up the fins for installation. Marked off sanding areas on each fin with painters tape, and tested fit. I found a steel ball tool used for decorating cakes, that I think will work nicely for Fin fillets, and it should clean off with acetone after using it. Visually matched up the circumference of this with the placement of the tape, so I can just leave the tape on the fins when I come back to make the fillets. I'm only going to glue the roots of the fins in today, and will wait to do the interior and exterior fillets tomorrow. Note: the aft CR and tail are not glued in yet, I just like putting it in there for photo ops because it looks killer!

IMG_20201126_152953.jpg
IMG_20201126_155244.jpg


Really looking forward to this build! The thing already looks freaking awesome half built on the stand. Thanks in advance for any thoughts!
 

mo2872

Well-Known Member
Joined
Jun 22, 2020
Messages
355
Reaction score
289
Location
NE OK
Interesting kit, good luck on your certification attempt! Oh, and nice Bo!
 

dr wogz

Fly caster
Joined
Feb 5, 2009
Messages
5,917
Reaction score
1,134
Location
Land of Poutine!
I have one on my bench too!! (Been about 2 years now!) you'll be my inspiration to finish mine!!

Mike's kits are top notch! And he is a great guy (flown with him a few times!)

A note for the next build: add that extra block to the centering rings, and screw your buttons into that. and I would comment that your upper button is too high up. (You want the buttons as low as possible, to keep them on the rod as long as possible.)

and my cats get in the way too!! :D
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
Shoot, great tip to bond the aft rail button to the aft CR. And for future builds, noted, on the placement of the forward rail button. I had considered keeping it lower, to keep it on the rail longer for a higher "leaving rail" velocity. But I was also trying to balance that a higher ratio of (Rail Button Distance) : (Length of Airframe) could minimize shearing torque on the rail buttons while it's on the rail. Perhaps I placed too much concern on that, and not enough on minimum velocity. Not too worried about it, because I'm going to be flying this on large motors, going straight to L2 Cert. Will def keep in mind on the next build
Is there a good rule of a certain number of airframe calibers distance?

The fins set great, will go and and both sets of inner fillets on the MMT and the inner airframe tomorrow morning.
IMG_20201126_172339.jpg
IMG_20201126_232821.jpg

IMG_20201126_232837.jpg


While the fins were setting, I managed to build the Eggfinder LCD in about 90 mins, and had a successful first boot! Going to look for a sweet momentary switch to use with a thumb, and design a pistol grip handle with slanted display to 3D print. So many fun projects with this end to end! Very happy to be getting back into HPR, it really is a craft that let's your imagination run wild and draws on all sorts of skill sets.

IMG_20201126_223650.jpg
 

Tobor

Get your peanuts....
TRF Supporter
Joined
Oct 8, 2016
Messages
1,900
Reaction score
547
For your momentary switch, check out Bulgin vandal resistant switches (Link).
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
Nice, I found similar style momentary SPST switches at Mouser, already ordered it, or I would have checked out the Bulgin switches.

Also ordered an NKK locking lever toggle switch for power. I like the idea of not accidentally bumping it and powering off while using.
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
Quick update on the build progress. The fin fillets cured very nicely, I think I'm going to continue to use the clay modeling toolkit in the future.

The last few days have been sanding and priming.

Mike at MAC Performance has been fantastic to work with. He gave me nearly an hour of his time to answer my questions and give his input for my L1 cert. I also love the canvas phenolic from MAC. It sands and prime very easily, and wow, what an improvement from filling in airframe grooves when I last built a rocket about 12 years ago. MAC Performance canvas phenolic paired with Wildman nosecones are just a match made in heaven.

I've got some of the painting done and will share more soon!


IMG_20201201_155600.jpg


IMG_20201201_182647.jpg


Very happy with how the fillets turned out
IMG_20201201_182711.jpg
 

SnapRoll

Active Member
Joined
Dec 2, 2020
Messages
29
Reaction score
33
Couldn’t agree more. The quality of MAC Performance stuff is second to none.
 

SnapRoll

Active Member
Joined
Dec 2, 2020
Messages
29
Reaction score
33
Hotwings, is your Bo a 33 or a 36? Can’t see the tail so doesn’t look VTail.

Cheers from a proud Cessna 182 and Extra 200 owner.
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
A36TC. Although I sold it last year. I'm commercial IR, going to do ME After the new year and also finally finish my CFI. I've got access to a Baron thru a friend I can fly once I finish the ME.
But one thing at a time, aerospace hobbies are expensive!!

Probably focusing on getting through TRA L2 over the Winter, and pickup Flying again this summer.
 

SnapRoll

Active Member
Joined
Dec 2, 2020
Messages
29
Reaction score
33
Hard to beat a 36 for what it does. Nothing flies like any of the Beech(es), including the Baron. I used to fly Caribbean charters in a B55 and it was a delight to fly.

The 200 is a doll. It’s sensitive, but a well balanced aerobatic aircraft. I’ve done very well in aerobatic competition with it. After doing a bunch of import flying on 300S/L and 330SC’s, those airplanes will ruin you royal, but the price point of the 200 is very hard to beat.

I’m an Extra instructor all over the world. If you ever find yourself in TX I’ll be happy to give you a ride.
 
Last edited:

mo2872

Well-Known Member
Joined
Jun 22, 2020
Messages
355
Reaction score
289
Location
NE OK
Sidebar.......it amazes me how closely some of us are linked. So many pilots on here chasing rockets, myself included. And so many Beech lovers!!! Nothing may run like a Deere, but absolutely NOTHING flies like a Beech!
 

SnapRoll

Active Member
Joined
Dec 2, 2020
Messages
29
Reaction score
33
Sidebar.......it amazes me how closely some of us are linked. So many pilots on here chasing rockets, myself included. And so many Beech lovers!!! Nothing may run like a Deere, but absolutely NOTHING flies like a Beech!
That’s great brother.. it is really amazing how we are linked and what a small world it is. We all love and appreciate the stuff that flies! 🙂
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
That’s great brother.. it is really amazing how we are linked and what a small world it is. We all love and appreciate the stuff that flies! 🙂
Couldn't be more true. Love seeing the mutual interests and skill sets in this community!

And SnapRoll, oh wow thanks so much! We actually have family in TX (also a Bo owner!). So next time we fly over that way I'll message you!
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
And final touches on the paint job done.
IMG_20201204_153747.jpg


So the kit is complete! We just got another MAC Performance kit in the mail today, 3" Scorpion! My better half is gonna build that, as she saw my rocket, and wanted her own! So she'll do her L1 sometime early next year likely. We'll do a build thread on her progress.
 

Saint_Tiki

Well-Known Member
Joined
Oct 6, 2020
Messages
54
Reaction score
55
And final touches on the paint job done.
View attachment 441201

So the kit is complete! We just got another MAC Performance kit in the mail today, 3" Scorpion! My better half is gonna build that, as she saw my rocket, and wanted her own! So she'll do her L1 sometime early next year likely. We'll do a build thread on her progress.
Wow that looks fantastic.

Just got L1 cert'd a 3" MAC scratch built kit a few weeks ago. Mike was great to work with. I drafted up a design and he sent me a complete kit, dry fit, to all my specs.
 

hotwings

Well-Known Member
TRF Supporter
Joined
Nov 18, 2020
Messages
46
Reaction score
84
Location
Melbourne, FL
Wow that looks fantastic.

Just got L1 cert'd a 3" MAC scratch built kit a few weeks ago. Mike was great to work with. I drafted up a design and he sent me a complete kit, dry fit, to all my specs.
Thanks!

Agreed, have really enjoyed working with Mike! The canvas phenolic really is top notch. And interesting idea, I didn't realize this is something MAC Performance did. I want to build a 6" dual deploy for my L2 after the new year. I was planning to build the 6" Blackfly. Maybe I'll sketch up something in Rocksim.
 

Saint_Tiki

Well-Known Member
Joined
Oct 6, 2020
Messages
54
Reaction score
55
Thanks!

Agreed, have really enjoyed working with Mike! The canvas phenolic really is top notch. And interesting idea, I didn't realize this is something MAC Performance did. I want to build a 6" dual deploy for my L2 after the new year. I was planning to build the 6" Blackfly. Maybe I'll sketch up something in Rocksim.
I think most of the kit makers are pretty willing to do custom designs. It’s really just tubes of different lengths and custom shaped fins and slots at the end of the day. I sent MAC an OpenRocket file, a parts list, and a drawing with measurements for the fins. It wasn’t much more expensive than a stock 3” dual deploy kit. Great deal and feels like it’s really my own. Plus I feel a lot more comfortable with the stability of the design having messed with it so much in the sim.
 

Attachments

mbeels

Yes balsa
TRF Supporter
Joined
Feb 9, 2019
Messages
2,543
Reaction score
1,331
Congratulations, and beautiful rocket with a really classy finish! Well done!
 

Tobor

Get your peanuts....
TRF Supporter
Joined
Oct 8, 2016
Messages
1,900
Reaction score
547
Sweet! Big congrats. Welcome to the world of "The Thinner Wallet".
 
Top