Cj builds WM Mach-2 rocket [2-stage]

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blackjack2564

Crazy Jim's Gone Banana's
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Well here ya go M-2 fans.
This was kinda a ringer last BS sales, only 65.00 and Maximum 54 motor capable.

I couldn't resist so I got 2 ta tinker with.

Designed with the military in mind, to fire L-1,000's to test "something".
It's a scaled down Falcon, with ease of build & survivability, being foremost.
Normal price 90 bucks.

Just a simple Nose cone Dual-Deploy [Head End Deploy H.E.D.] mach-busting high altitude kit.

32.5in long airframe. NO slots. Thin wall G-10
54mm. Filament wound 5/1 Von Karman Nose cone. Thin wall G-10
Metal tip with recessed threaded-shoulder for non slip fit/stainless E-bolt for recovery harness

5in. coupler NC shoulder/ Av-bay [H.E.D.]
1 in. vent band [for av-bay]
2 aluminum stepped av-bay lids.
Black epoxy kit [Pro-Line high temp ]

4 fins Falcon series 1/8in. G-10 beveled.
G-10 fin alignment guide.

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Picture shows 2 glue kits, due to I bought [2] Mach-2 kits. Only 1 glue per kit.
They just happened to be packaged together.

PLEASE bear in mind...FINS do not come beveled like these!
they come beveled very nice.....these were sent to the "bedazzling" bench!
Nice sharp 7 degree.

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I have some mods in mind for a 2 stage.
To keep it simple the booster will remain 54 minimum.
Sustainer will get dumbed down to 38mm, so a simple coupler I/S may be used.

No slotting, just a simple 38 motor tube & 2Cr's to get glued in place.
2in. coupler in front of motor mount to act as engine block.Front CR will butt against coupler.
Coupler also pinned through airframe [just to be sure].


For flying 38's in the booster this was made.
Simple 38 MM tube with recovery Y-harness glued on sides through a notched top Cr.
Held in place by rear rail button through airframe into adapter lip.
Just a snap ring holds motor in place, inside the custom Al 38/54 tailcone.




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Love the tail cone retainer!


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Can you pleez 'splain "bedazzling bench"?

Work bench containing "special tools" for turning mundane rocket parts into rocket "bling"!
As in the "reedunkulas" beveling put on these fins.


I dunno what you're selling but I subbed...

Killin it something fierce BJ

Nate

I'm not the seller...that's Wildman. I'm the "sellee"....or enabler!



Love the tail cone retainer!

There is a real lack of 54 airframe to 38 motor tailcones/retainers. This solves that issue very nicely....Thank you Charlie.

I'm waiting for the Mach 3+ to come out!

What? Huh??? It's already here!@##@!!!! I solved it.
Mach 2 + Mach 2 = Mach 3 two stage.
Of course I went to Jethro Bodine school of ciphering.:lol:

https://itsallsatire247.wordpress.com/2010/06/25/jethro-bodine-named-new-education-czar/
 
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To get the party started:
Fins will be surface mounted on both stages [54 & 38mm motor mounts]
I supplied extra parts for reduced motor size on sustainer.

First wrapped 3/4in. tape around airframe, to mark fin positions for lines with angle iron. Keeping things nice & straight when using alignment guide. I already had this one ready, why bugger up the new one. [guide]
I want my fins a bit off rear of airframe, let the motor get first ground hit 'stead of fins, during recovery.

Wipe down airframe with Acetone after light sanding for glue adhesion.
TIP:
1 Fin gets a couple drops of CA to hold on airframe after aligning on pencil marks.
This keeps fin guide in place while tacking on the other 3 fins with epoxy till cured.
No more having stuff slip-sliding all over the place, while trying to tack/glue fins in place.

Then break off the CA'd fin. sand root clean & airframe. Acetone wipe.
Re-attach with epoxy to airframe, while using the other 3 fins to hold fin guide in place.

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TIP:
If you redo or sand bevel on fins, be sure it's same on both sides! [identical on both side]
If bevel is off just a bit on one side, your rocket will spin at these high speeds that go with minimum diameter.

Hysol is epoxy I use for this.
 
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TIP:
1 Fin gets a couple drops of CA to hold on airframe after aligning on pencil marks.
This keeps fin guide in place while tacking on the other 3 fins with epoxy till cured.
No more having stuff slip-sliding all over the place, while trying to tack/glue fins in place.

Then break off the CA'd fin. sand root clean & airframe. Acetone wipe.
Re-attach with epoxy to airframe, while using the other 3 fins to hold fin guide in place.

Just wanted to say thanks for including the "Tips" in your build threads. Things like this are such simple solutions that make things so much easier, but I'm not sure I would ever come up with them if just left to my own devices.
 
Subscribed! Go CJ, go!


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Thanks Guys.

Fins all tacked on.Time for fillets
Tip:

To get perfect fillets, with no edges that stick up & need sanding.
Use your smoothing tool for guide to place masking tape.
Coat edge with Sharpie/marker & rub/roll along V-groove between fin and airframe.
It will leave a line you place masking tape on.

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When pulling glue smooth, all excess will be on the tape, leaving a perfect fillet & all remaining glue will be removed with the tape.

This is a 1 in. diameter section of PVC pipe, which I use to smooth fillets.
Now is when you tape off each fillet to shape desired.
Remove tape about 15-20 minutes after pulling smooth.

DSCN0228.jpg

Depending on glue used, I sometimes wait as long as 45 minutes after mixing to allow epoxy time to thicken, so it does not sag after pulling to shape. Then I put it in place & smooth.
This is all temperature dependent .
 
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The Giant Leap 54 to 38 tailcone fits "OK" with WildMan thin wall tubing. The OD when mounted leaves about a 0.01" lip with the tailcone being slightly larger. The fit between the motor tube OD and tailcone ID is also a bit loose but 3 super thin strips of masking tape placed around the motor tube 120 deg apart from one another will tighten it up and leave plenty of surface area for a good JB Weld bond.
Here's a pic showing the OD lip. I was originally going to smooth it out with spot putty and primer but decided to leave the whole rocket naked and just live with the tiny lip.
IMG_1768.jpg
 
Lathes are wonderful tools.


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Remove tape about 15-20 minutes after pulling smooth.

View attachment 336468

Depending on glue used, I sometimes wait as long as 45 minutes after mixing to allow epoxy time to thicken, so it does not sag after pulling to shape. Then I put it in place & smooth.
This is all temperature dependent .

Definitely temperature dependent...I get worried about epoxying the tape to the rocket, so I've started putting two layers of tape on to mask the fillets (both right exactly on top of each other)....if I pull it up a little early and there is any sag or pull, it just goes onto the second layer of tape and is way easier to clean & manage.

Yes...I'm a bit OCD.
 
I use Proline 4500 most of the time, generally because I've been doing lots of colored FG so I didn't intend to paint, so the black fillet just looks good. When I know painting is involved I've also used 30 minute Z-poxy, both usually lightened with microbubbles unless it's MD. I don't wait any beyond the time it takes me to mix, and I pull the tape as soon as I've finished drawing the fillets, because it still flows enough that what epoxy smooshed-out onto the tape would just flow back into the fillet region if I didn't pull it within a minute or two, and then I think I'd have an issue with pulling the tape since the epoxy would have flowed over the edge of the tape, instead of there being a clean divide where the tool ran along ("tool" has been a short piece of PVC pipe, a plastic spoon or a spent AAA battery, depending on the radius of the fillet I wanted).

I always wet the edge of the tool with a sharpie and rub it along the fillet to figure out where to place the tape. My only gripe is with the leading/trailing edges, where depending on the fin angle it can be tough to get into with the tool, or as I round the tool around the fin edge the tape doesn't exactly follow the round. Haven't figured out a great solution there yet, though perhaps I'm just putting the pieces of tape I angle at both edges (eyeballed 45°) too far away, the tool does end up against the airframe rather than the tape, so there winds up being a part where it's effectively flat (no epoxy), then some more epoxy before it finally gets to the tape edge. Passes the 1-2 foot test, but still. :p
 
time to catch up on this build.....

This a Mach-2 54mm minimum diam. converted into sustainer. I had some parts around I converted into a 38 motor mount. 6inch 38motor tube- 2 CR's 54 to 38mm.
Added a recovery Y-harness to it.
Inserted a coupler [2in.] infront of it acting as motor block, since there are no fins through the wall adding structure.
Followed by motor mount/harness [1/4 Kevlar] Glued it up.
Rear Cr is recessed 2.75in. into airframe allowing a bit more than 1 caliper of I/S .
Used a home made motor retainer. Simple Al sleeve with snap ring to hold motor in place.

DSCN0292.jpg




Next day I realized what a bone headed thing I did.......forgot to sand interior of airframe tube!:y:
Sooo I drilled and tapped through airframe into coupler between all 4 fins to add strength & assure everything stays put when flying high thrust motors. Used 4-40 stainless set screws.

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The Mach-2 comes with metal BP's & 5inch NC coupler/av-bay.
I need 6in for my GPS & replaced metal with stepped G-10 BP's for radio transparency.
Replace standard coupler with a 6in.
#6 all thread tie rods
Al charge holders long and thin for high altitude flights. They hold 1.5grams BP. I only need .5gram for this.
Holders threaded to receive #6 rods, eliminating extra hardware.

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Placed cone in airframe just to hold it vertical.
Insert av-bay WITH FRONT BP ON! otherwise you won't get proper spacing for vent band.
Mark around coupler.

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Remove tape around line to catch excess glue.
Place vent band on, trace line on other side.
Sand between lines & glue in place.

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Cut G-10 sled [3/32] to fit bay.
Finished bay with 3 holes 7/64 evenly spaced.

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Tie recovery loop to eyebolt BEFORE installation. Sure makes it 'Mo easier than after....ummm.ummm.:face palm:

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TIP:
Make yourself this simple tool for installing eyebolts into nose cones.
section of PVC pipe [or dowel] notched with Dremel or hacksaw.
Makes installation a breeze.

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Install E-bolt with harness loop attached.
Put some thread locker on E-bolt.

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Semi finished NC/av-bay.
Need to add vent hole to cone
2 shear-pins to cone [2-256]
Vent airframe, I'll do this later when I set up for drilling charge wire holes in Av-bay bulk plates & rail button holes.

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Last night I re-did the fillets.
First go it was cold and they sagged quite a bit.
These are A-OK!
There was plenty of glue leftover from the Nike Smoke build.
Pulled smooth with a 1inch tool.

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Set up to do fins on booster.
Charlie made slightly larger ones for Booster. [about 3/8's all round]
Original on top of new ones, after sending them to "bedazzling" bench for bevels.

DSCN0359.jpg



Wrap layer of 3/4 inch tape flush with rear of airframe.
I want fins slightly above rear end.
Stick tube on my marking guide for drawing lines. [oviously pic was taken after the fact...lol lines already shown.]

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Angle iron & draw all 4 lines to aid keeping fins straight when using alignment guide.

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Manny should be here any minute, & I'll tack fins on when we fillet the Smoke.
 
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Dec 2018
Back in the saddle building again!


Booster fin attachment is just a duplicate of sustainer, no point in photo essay that again, so on to interstage coupler [I/S].
Since I scratch building this thing I was on my own to design the I/S coupler:
7 in coupler
2.5in. ventband
1/2in. slice of vent band for interior ledge to hold coupler BP in place
av-bay lid [BP + CBP]
2 #6 althread nutz etc.
1 # 10 [3/16] eyebolt.

DSCN1184.jpg

Need to remove a slice from vent band for BP ledge.
slice in half, compress slide into coupler.
Mark overlap, cut and remove section so ledge fits.
You can do this for any I/S rather than just glueing BP in place, makes for stronger assembly.

DSCN1191.jpg

Now that part fits, I can assemble & dry fit interior parts for I/S.
Place motor into sustainer. Make sure nozzle cap in on so later it will fit!
Place ledge & BP into coupler, push into sustainer. Motor will push BP/ledge into coupler where it belongs
Now I have parts dry fitted in place.
Measure distance from booster side for later assembly and tie rod length.

Glue av-bay lids together. Mark and drill needed holes for rods/seperation charge/fill center hole with epoxy.
Assemble for permanent install.

DSCN1192.jpg

Reach inside with dowel and smear glue for ledge/BP assembly.
Once in place, check fit with sustainer & fillet both sides with glue.
Sustainer side
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Booster side.Close inspection see the ledge holding BP

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Fit vent band and glue.
Assemble av-bay lids, install eyebolt, drill ejection charge wire hole.

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Before I started gluing anything, I made sure all tube/vent band edges were square.
All went together perfect!
4 holes for altimeter vent & the oddball for switch. Will re-drill larger switch, hole after I see how things line up on sled.
4 holes centered between fins to lessen turbulent flow & bogus readings.
Finished I/S installed.DSCN1202.jpg

First look at the whole stack.
All glass and glue done.
NC has recovery gear installed along with altimeter/battery/chute/nomex/cord.

Weight is 4.6 lbs This thing is a fly weight!
It should really sizzle with a 54mm 6xl in booster and 6xl 38 in sustainer.:cool:

DSCN1203.jpg

Only thing left weight wise is Booster electronics and recovery gear.
 
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Do you know what motors you are wanting to fly this on yet? Great build with great photos! Thanks for sharing
 
I have not done anything on any of my builds since late March.

On April 6 I underwent Open-heart surgery.:dark:

1 valve replacement, and double bypass. This was totally unexpected & has screwed with my life quite a bit.
I have been out for just 3 weeks and started my re-hab today.

So until I am cleared to build stuff again , everything just sitting in Limbo. I think Airfest in Sept could be my first launch if everything goes well, so we shall see..............

Cannot lift arms above my shoulders, or weight over 3lbs etc..etc....etc.. No driving till june/jJuly. List of stuff to recovery is long as arm.

But to answer....I have much to do to finish this & my other builds. [2-stage Nike-Apache & Punisher 2 -stage rebuild]
Fit the I/S coupler...add all electronics & recovery etc.... I will document when i do it. Just pulling the lever on my drill press is a no-no right now.

Was hoping to fly a high thrust 2 grain 54 [J-460-T] or Warp-9 etc in booster and a 6 grain white thunder in sustainer...for shakedown flight.
After that a 6Xl whatever I can buy, at the time for booster [L-935 hope] to a 38mm Mellow longhorn in sustainer.

That should kick it in the butt.
 
Wow! Sorry to hear about your heart problems CJ. I hope you're up and running around ASAP.

Take care,
 
Jim,
I’m so very sorry to hear about your medical troubles, but I pray you’ll feel much better soon. You’re a valuable member of the rocketry community and a valued Tripoli member. Please feel free to pm me and I’ll send you my phone number if there’s anything I can do during your recovery. Or even just to shoot the bull.
 
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