Wildman's MACH 2 rocket

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That is a NICE av-bay and retainer!
How much BP are you using and shear pin info?

I'm using the AeroPack minimum diameter retainer with the eye bolt for recovery and threaded forward closures with the matching adapters.

Two #2-56 pins for each separation.

Apogee: 0.65gr, with 0.8gr backup, both in charge cups
Main: 0.8gr in a glove tip.

I ground tested these and they were pretty zippy at 5,000MSL, and they apparently worked fine at 28,000MSL. I use long 3/16” Kevlar harnesses. YMMV!
 
I machined a retainer similar to the glue in commercial MD retainers, but mine is held in the air frame with 4 set screws through the airframe so it’s removable. I use a threaded forward closure and 5/16” set screw into this retainer.

Buckeye-

Yep, NCR with 35k’ call-in windows. Ebay pics below, I had to order a longer coupler to fit my long sled.


Beautiful craftmanship. Really nice.
 
Here’s one more data point for the Mach 2 kit, I’ve really enjoyed mine! After a H130W shakedown I flew mine on the AT 54/2560 K480W to 22,285' AGL (recorded by RRC3 baro altimeter and verified by GPS). Velocity data from the altimeter was not reliable, but the flight simmed at ~M1.8. This was tower launched with no rail buttons or lugs.

The K480W landed just under 1 mile from the pad. It outperformed my OpenRocket sim by 3,000' when set to "smooth paint" finish, so be advised if you are simming near the limits of your club’s waiver!

I used Hysol E-120HP for the fin roots (thanks for sharing this recommendation, CJ), and then pulled generous 1" diameter tool fillets over that after sanding again using the included Proline4500.

No tip-to-tip. I clear coated everything with SprayMax 2K clear (which is super nasty stuff but gives good results, wear a real respirator). This was the second flight and the fins are rock solid. Only consequence of this fast flight was my vinyl flyer info sticker got melty.

I used ~12" and 42" ultralight spherachutes which gave me 80 and 26 fps descent rates. My dry weight was ~1305 grams.

Next flight will be the dual thrust K375NW, hopefully in early August.

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Do you have any diagrams or pictures on how you set up your dual deploy? I'm looking for ideas.
 
Cameron Anderson said:
Do you have any diagrams or pictures on how you set up your dual deploy? I'm looking for ideas.
I took a few pictures tonight as I prepped for this weekend’s flight.
 

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I took a few pictures tonight as I prepped for this weekend’s flight.

Nice clearcoat. Brand? Maybe you already mentioned this upthread.

I can't see the main charges. Will they run up into the tip of the nose cone?

I also label my 9V batteries!
 
Nice clearcoat. Brand? Maybe you already mentioned this upthread.

I can't see the main charges. Will they run up into the tip of the nose cone?

I also label my 9V batteries!

SprayMax 2K clear, it's nasty stuff but works well. Wear a real respirator, read all the precautions.

I put the main charge in a glove tip right on the ebay lid. Same as all my other HED rockets, 54mm, 3", 4" and 6". I've never put the charge up in the tip of the NC because packing recovery gear around the wire seemed like a hassle. So far it's always worked great. The 54mm NC is packed tight, even with an ultralight (thin-mil) chute. Watching it ground test gave me confidence that it would work just fine.
 
Got around to rough fitting parts tonight and I noticed that half of my tube edges aren't square. My main airframe has one square end (looks like it was the factory cut end) and the other end was off by 2mm. My switch band is off by over 1mm on both ends and one end of my coupler is off over 1mm.
This is my first Wildman kit, is this normal or unusual?
 
That’s fairly common for Wildman kits. There’s been a few threads about said topic.
 
Fourth fin getting tacked on. I do them one at a time. I like to use cut out foam board, even with fin guides.
 

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Home-made MD motor retainer. I epoxy allthread with a nut into the ejection well of a DMS motor (L1000 here). Then I epoxy a coupler with a bulkplate inside the airframe as the anchor. I drill a hole in the bulkplate and slide the allthread through. For assembly I use nuts on both sides, but when I fly I only plan on using a nut on the high side which will allow the allthread to move up under thrust, if it needs to without breaking the assembly, but still keeps the motor from falling out the back end.
 

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Mine came in at 1290g all ready to go. Probably a bit heavier than some. I have a 42” spherechute ultralight main and 12” spherechute drogue. I made a coupler/forward retention point that can move to different spots and that added some extra weight. Has dual altimeters and a tracker in the ebay.
 
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Got around to rough fitting parts tonight and I noticed that half of my tube edges aren't square. My main airframe has one square end (looks like it was the factory cut end) and the other end was off by 2mm. My switch band is off by over 1mm on both ends and one end of my coupler is off over 1mm.
This is my first Wildman kit, is this normal or unusual?
Nah, very normal. Tim cuts tubes to length on a chop saw, so there's always a little bit of unevenness. (I keep telling him to do them on the slotter but they'd take a lot longer that way!)

To get things even, you can do the paper/sanding block thing, or--as Griffin taught me--stick a coupler in, put the other tube (switchband, nosecone, etc.) on top, squeeze together axially, and twist back and forth to sand. The fiberglass is quite abrasive and does a good job of "lathing" the high spots down in no time flat.
 
What weight are you guys coming in at?

1,198 grams airframe complete (internal motor retainer, primary and backup ejection charges for main and drogue, 10' streamer, 24" x-type main, Raven 4 primary, RRC2 backup, T3 GPS, 7.4v lipo, two 3.7v lipos, fiberglass electronics sled, two pull-to-arm switches, clear coat over the airframe)

3,392 grams w/ motor.
 
Those are scary straight and parallel fillets! Did you tape them off before applying the epoxy? Regardless, those fillets are amazing!

Yep, good masking tape, want to say 3/8" thick, but I can't remember. I use rocketpoxy a lot and I think the dye makes it creamier. I know the dye is an astronomically small percentage by volume, but dyed rocketpoxy seems to pull fillets better than non-dyed.
 
Yep, good masking tape, want to say 3/8" thick, but I can't remember. I use rocketpoxy a lot and I think the dye makes it creamier. I know the dye is an astronomically small percentage by volume, but dyed rocketpoxy seems to pull fillets better than non-dyed.

I wish I’d thought of that during my recent build. I also used rocketpoxy (without the black pigment) and they came out pretty decent, but I still went back with diluted wood filler for better cosmetic appearance.

Next build.
 
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