Cj's builds MadCow Nike-Apache 2-stage

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blackjack2564

Crazy Jim's Gone Banana's
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If you are building one of these 2-stagers, you will find extreme difficulty in mounting a conduit small enough, to run wire through centering rings for sustainer ignition. H.E.I. is the way to go.

We are in the midst of a run making these CTI/AT and if you have any interest in these, varying sizes,29mm 38mm etc.
Apparently that thread has been moved to another dimension. So PM me with any needed info wanted.
...............................................................................................................................................................

Jan 18 2018.

Well I finally got my camera back after it went by Savannah twice ending up in Jacksonville, then past me again on the way to North Carolina...LOL Finally back to Jacksonville then landing on my doorstep 3 weeks after being shipped 3 day priority.....LOL So here we go:

Pics were taken last month, just hadn't loaded them on computer.

Well packed parts, I was surprised so many came wrapped tightly in paper, NC, Transition,& most small delicate type parts. Fins/rings all bagged or wrapped..impressive!
Reminded me of my first Binder Kits that were also shipped very well!

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Layout of all parts in groups of the build:

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First to be changed is the I/S:
comes with just the transition-coupler - centering ring.

I'm adding stepped av-bay BP's to which the CR & glued in Coupler will sandwiched together by the threaded tie rods going through bay.
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Here's the 3D printed scale version. Hard to believe it's printed. It was annealed at 185F for 4 hours, to toughen it up for all you worried about it, "taking the heat" LOL.
Complete with stainless bolts and accurate vent placements! This will be for my true scale version later, I will build/ fly the stock one on this build so everyone can play too. Blow it up all the way [clk 3x's] see how smooth & detailed. The 38 coupler is carbon, NOT printed.

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So now the fun begins over next few days/weeks!
 
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BUILD BEGINS: Jan 21-2018

Since I have extra mixed glue, from the 3/4 Smoke build, why waste it.
So I began 29 motor mount for sustainer & BP's for av-bay.

Filed 2 notches in front CR's for 1/8in. Kevlar [750lb] Y-harness.
Just long enough to stick out of fincan for recovery gear attachment.

Measure from rear of airframe to front of slot...transfer to MM tube.
Slide on CR over kevlar to measured mark, add drop of CA to tack.
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Place rear CR on MM tube. With fin-tab held to front CR.
Push rear CR into place and tack with CA.
Assembly should fit perfectly between slots,with Cr's on each end of slot & WITH motor mount flush to rear of airframe.

Insert into airframe, check fit. Make any needed adjustments.
I just used thin CA to hold rear Centering ring in place.
I don't want a fillet on either side to interfere with proper fit of interstage-coupler on bottom side, nor fin fit on upper side. I am "sandwiching' fin between CR's. You don't have to.....I want to.
My I/S coupler will butt against CR to make a better fit.
OK...move on.

AS discussed in posts 25-26-27, NO motor retainers were found that would allow I/S coupler to fit over them, so friction fit & tape ring will be used as shown in those posts.Normally retainer would be glued on during this step.

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Masking tape just temporarily holding Kevlar in place. Remove.
Epoxy Y-harness in place. Don't get glue on cord where it goes through CR. Small fillet on top of CR...NOT bottom, would interfere will fin fit.
After encapsulating the Kevlar, wrap electrical tape around MM tube, compressing glue & kevlar for better/neater job. Set aside to cure.

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Making av-bay lids:
Have already sanded 1 side of each Av-bay bulk plate.
Sparingly apply epoxy to one side, I do not want so much it oozes out when compressed, so it needs sanding.

Slide large BP on eyebolt first, then smaller one.
Barely snug up nut.

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TIP:
Place assembly on coupler
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Then slide airframe over to ensure proper fit.
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They will "self adjust"& center. Now remove & tighten nut .You will have not problem with fit.
I remove nut and repeat process with 2nd set on same eyebolt.
Just lazy...use 2 E-bolts if it suits you.

Do not leave BP's in coupler or airframe, if glue oozes out...uumm your screwed. It's in there .
 
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Jan 22- 2018:

Freshly "Bedazzled" fins came today. BEE-U-TEE-FUL ain't they! Old one next to new.
Not as sharp as the Mach-2 fins, as this is sport flier.

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Along with that fin guide for Booster and 2 stepped av-bay lids. [single piece , not messy gluing 2 together]
These go into I/S making it av-bay for booster.

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Removed electrical tape from MM tube. [no glue sticks to it, great way to neaten things up]
I overdid the epoxy a bit. Stuck MM assembly in the pipe to mark fin lines on MM tube and glue was in the way. Bit of sanding problem solved.
Tip:
Always check by dry fitting, to be sure Y-harness is between slots. I actually do this before gluing it on, should have mentioned it before....sorry.
I then use pencil and draw lines on tube, for ease of re-fit when time to glue. Just insert in tube and line up pencil lines through slot.

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Then I always re-check, making sure everything lines up and Y-harness long enough before gluing in.

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Sand fins 1/2 to 3/4 in. up from root for glue adhesion when tacking & doing external fillets. I find easier to do all at once.
Tip
Look closely at rear corner of fin. I barely rounded it over, just sand enough to knock off sharp edge. Do same on all outer edges, paint adheres better to a slightly rounded edge, rather than a sharp 90 degree one! Won't chip off when banging around.

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Pre-fit & number all fins/slots.
I used JB weld to tack on fins. [Just because it was on hand]
Used my "Double Dip" method.
Butter root of fin with epoxy, push into slot.
Remove, butter fin again, insert and leave in place. Doubling amount of glue!

After getting all in place I used a straight edge to align them in pairs [pic]
I had and alignment guide on paper to eyeball all with, just to lazy to cut out a cardboard jig.
Once happy, with alignment, I put a drop or 2 of CA on slot/airframe joint & let it run down.
This seizes immediately so no worries about fins getting out of place while glue cures.
Makes quick work of fin alignment.:smile:

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Jan 24 2018

Interstage coupler I/S Step 1

NOTE: BP's/av-bay lids needed to convert I/S coupler into electronics bay, DO NOT come with kit. Must be user supplied.

It took some ciphering to figure which order of steps so everything could get properly glued.
Used 3/16 [#10] all thread for tie rods. Cut to 6 1/4 inch long.
Hole for same are 3/8 [centered] from BP edge.
Use 5in coupler.

Both lids get bolted together for drilling. I mark one edge side, when assembled [if holes are not exact spacing] tie rods will align, not everyone has a drill press. 3/16 in bit. Just keep lids oriented with mark on same side.

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CR for I/S coupler needs tie rod holes also, can't bolt that to lids, there a BIG hole [38mm] in center.
I made a jig using slice of 4in. coupler [cut off laying around] I slit it, now becomes "spring loaded" & grabs both CR & drilled lid.
Now easily drill through previous Lid holes into CR, & all holes properly align for tie rods.
[If ya have a vent band laying around you could do all 3 at once....I didn't]
Edit: you can also tape the CR to bulk plates with masking tape, then drill holes.

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Drill 1/8 hole for separation charge wire. Then chamfer/bevel edge to make finding hole easier when fishing charge wire from top of I/S.
There are 3 layer of G-10 rings getting bolted together, I don't think washers are needed. Place tie rods through lid and CR, check fit in I/S shroud, tighten nut on inside & out.
Drop of Loc-tite blue thread locker on each nut & done.
Sand inner & outer edge where coupler gets glued into CR.

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I had to think about this for awhile, glue what to what...in what order, so glue wouldn't sag I could double check fit as I went. Following process is what I came up with after several different methods of dry fitting first.
Mix small of epoxy for next steps.
Cover uneeded 1/4 hole with tape on bottom side/where rods hang.
Fill with glue, tape over it. [both sides taped] Can't leak out while working on next steps.

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CAREFULLY put small amount of epoxy along inner edge of CR. Not too much, when coupler get stuck in, ya don't want glue getting into charge hole!

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Gently insert Coupler and twist slightly to evenly distribute glue.
MAKE SURE COUPLER IS PUSHED IN ALL THE WAY AND SQUARE TO PLATES or your shroud won't fit later!
Apply exterior fillet & set aside TO CURE BEFORE going on to next step.

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NOTE:
After glue cures fit assembly into shroud. Draw line around coupler where it sticks out. This is where glue goes, in next step. Line seen in above pic.



Step 2

Don't attempt this unless glue is cured from Part 1.
Read this first, sand where glue goes.
Place small bead of epoxy where transition goes from flat to angled.

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Step 2 I/S coupler continued

Place a heavy "Bead" of epoxy around line on coupler on side of line towards lids. NOT ABOVE LINE.
When curing we want glue to sag around interior creating an internal fillet. This happens because we set I/S upside down & let gravity work.
Due this fairly quickly so glue doesn't settle on coupler before inserting.

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Carefully insert assembly INTO shroud, hold it facing down so glue settles.
Be careful not to hit sides and wipe glue off coupler.
Be sure lids/BP's seat all the way into shroud, if you put too much glue on joint where 4in coupler goes [like I did] it takes a couple of pushes to get glue displaced and "seat" the assembly or the I/S will be slightly cocked to one side.

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Light, thin coat of epoxy on side wall of shroud.

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Insert 4in. coupler, twist a bit to evenly coat epoxy.
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Should look like this.
Clean any epoxy off places it does not belong!

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Leave upside down for several hours so glue settles around 38coupler/shroud and forms internal fillet.
That finishes the glue up of I/S.
Picture A & B
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Yeah..that's a sneak peek at MM assembly for the Smoke/booster section.

Hope my process of assembly helps other attempting conversion to 2-stage.
I would love to see other methods, some of you may have come up with...especially if they simplify the process.

Jan 26 2018 Fincan Booster

Measure slots and distance to rear of airframe.
Transfer to MM tube & mark. 1.5 inch for rear CR.....7.5 for front CR. [on mine]
File notches in front CR for recovery Y-harness [3/8 Kevlar]
Check fit with fin. Install and draw lines through slots onto MM tube.
Remove and align Y-harness BETWEEN the fin lines. Tack CR's in place with CA.
Put assembly into airframe, if fit OK, remove and epoxyCr's into place on MM tube.
Glue on motor retainer. [JB weld]

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Encapsulate recovery harness with epoxy and wrap with tape.
set aside to cure. Above pic A-B




Insert completed MM assembly into airframe/align with slots.
Fit fins to each slot & number both. 2 of mine fit perfect....2 needed sanding to fit slot.
Tip
With fin in down position in slot, I draw line, when glueing fins on MM tube, this "tells" me I have fin pushed into position all the way. I will inject internal fillets, fins must be tight or glue will leak . Line also lets me know where to sand for external fillets.
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Tip
Kill two birds with one stone. Set fin along edge of table with root flush to edge.
Place trigger finger along edge of table, using it as guide.
Put thumb atop sandpaper where you want straight line sanding, here I place for external fillets above line 3/4 in.
Slide back and forth keeping trigger finger on side edge of table. You get perfect straight sanding lines with no scratches where not wanted. No Taping needed, real time saver & quick.
[I would be holding fin to table,with other hand, if not using camera.]

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Jan 26 2018 Fincan Booster continued

Getting ready for a glue marathon. We're going to do fillets on 3/4 scale Nike smoke & I know there will be plenty of thickens glue left over. So I'll prep:
Sustainer for 8 fillets.
Mach-2 rocket for 8 fillets.
Sustainer av-bay vent band.
Booster tack 4 fins in place.

Space tight in Apache payload. I'll move vent band up from center, yielding another 1in. for recovery gear.
Mark coupler 2.5 in. from top, insert 7in. coupler into bay and draw line around it.
Tape around line, slide vent band on, draw another line.
Sand inside band and area between lines on coupler.

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File half hole on each side of all slots for injecting glue. File rather than drill holes so I don't splinter airframe tube.

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Tape sustainer for 8 fillets & Mach-2 rocket for 8.
Mark for lines first, by coating edge of PVC tool with magic marker, while still wet, rub back & forth, leaving nice lines to tape.

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Slide MM assembly into position in Nike booster along with #'b fins in numbered slots. I remove and tack 1 at a time, leaving others in place.

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Working like a bat out of hell, I do all fillets, & remove tape on both rockets.

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Finally I remove one fin at a time, use my "double dip" method for tacking fins on.
Tack all 4 fins on Booster and align.

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Any body notice anything unusual about orange Punisher in back ground....LOL?
My autographed "Homer Hickam" rocket. We won drag race in OZ couple years ago.
Done for today, wait for a ton of epoxy to cure.:smile:
 
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Sustainer av-bay & NC mods Jan 29 2018

Av-bay coupler 7in long.
Cut 2 tie-rods from 4-40 all thread 7.5in. long [Grainger Supply- Mac Carr etc. mine from Grainger]
Eyebolts #10 [3/16] get more space on BP's

7/64 bit for all holes on BP's [tie rods & match wire holes]
7/64 bit 3 vent holes on switch band.
1/8 bit for Airframe vent holes.
5/64 bit for shear pin [2-256]
5/32 bit for rivets

Assemble tie rods into BP, add some blue Loc-Tite thread locker, this side is permanent.
Notice I moved vent band off center....it's now allows 2.5in into payload to yield more interior volume.
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Grind off excess threads from eye-bolt.

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Extra hole on apogee BP for 3rd pyro [motor ignition]

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When av-bay & NC are in place there is only 7in. of space for recovery cord/main/nomex in payload.
I placed vent band up 1 inch on coupler, only 2.5 in. goes in payload, & modified NC eyebolt into NC 3 inches.
Now have 11in. of recovery gear space.....'Mo better!
Replaced supplied Coupler BP with an airframe BP. install 3/16 eyebolt.

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Place onto NC coupler [after installing recovery loop harness] & slide into place.

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I gained 3inches of space vs gluing BP/eyebolt on rear edge of coupler!

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Hold coupler in place with 2 stainless 2-256 cap head [Frankenstein] screws!
I want to be able to remove, in case I come up with some type of Nc bay later, or replace the epoxy tip with a metal one. I don't think the tip will survive much abuse.

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NC gets 1 shear pin
Payload 1 vent hole centered [1/8 bit]
Fincan 1 vent hole centered between top MM CR, & bottom of where av-bay seats.[1/8 bit]
Av-bay held in payload with 2 PML style rivets.

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Part 1 : Inject & fillet booster fins. Feb 4


Mark tape placement with Sharpie covered tool, by sliding back & forth, as shown in sustainer fin attach Post #6.
I use a 1 inch diameter section of PVC pipe for my fillets. [both sustainer & booster]
Tape off fin/airframe to catch excess glue keeping fillets neat & less sanding to finish.
Inject glue into booster fins & do external fillet at same time.....to save time.
TIP:
I have found over the years of building that the same amount injected [10ml here] will also be correct amount for external fillets when sized correctly [10ml] How the amount 20ml is derived.

Mix 20 ml of epoxy.
Inject 5 into each fin. Syringe holds 10.

5ml into one fin.
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5ml into other.
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I add thickening agent [West 406] into remaining glue, still in cup.
Spread evenly into V-groove.

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Pull smooth with tool dipped in acetone or alcohol.
Remove tape carefully keeping out of wet fillet.
Admire finished work.
I do both injecting, immediately followed by external fillets to save time, and wasting glue.
Then after cure, this set, completely finished, rotate to next.
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Part 2 Feb 20

Drill bits to finish booster:
5/64 for shear-pins
1/8 for airframe vent & rail buttons
3/16 for I/S [av-bay vent holes] & switch access hole.

Mark for rail buttons.
I placed bottom 1inch from edge of tube. Top higher than usual due to it's supporting the entire stack on the rail. 8inch from top of tube. [Bondo spot putty on primed fillets]

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1/8 vent hole in airframe, to equalize interior/exterior pressure at higher altitudes.
Placed in center of Booster airframe.

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3 holes spaced around airframe for altimeter venting.
2 1/4 inch from top of tube. Horizontal line shows bottom of I/S location.
This puts vents right in the middle of av-bay [I/S]
Insert I/S & drill through both, I use 3/16 bit.
Tape on airframe-I/S joint holds everything in place while drilling holes.

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Pencil line shows bulk plate location. 3/16 hole for switch mounted on same BP or twist/tape wire switch.
This must be on I/S, obviously you can't run switch wire through airframe.
Shear pins [3] 2-256 located 1 inch from top of tube using 5/64 bit. Key mark uses same.
When doing shear pins, drill first hole, insert pin & then continue to assure alignment.

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This concludes build section of Nike-Apache, next the finish/paint & mounting of all electronics in both Booster & Sustainer.
I/S is ready for primer after removing all marks for hole positions.

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To make following the build coherent, this short cut will take you to next series of actual build posts:

https://www.rocketryforum.com/showt...-MC-Nike-Apache-2-stage&p=1759857#post1759857
 
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Should have mine soon...shipping notice for Sat delivery.

That being said...been having overwhelming response to our [Charlie/me] head end ignition module for 29mm hardware, both AT & CTI.
If you are building one of these 2-stagers, you will find extreme difficulty in mounting a conduit small enough, to run wire through centering rings for sustainer ignition. H.E.I. is the way to go.

We are in the midst of a run making these, and if you have any interest in these, varying sizes, check Area 51 thread :
https://www.rocketryforum.com/showthread.php?141609-Head-end-ignition-module for pics and info.


Apparently that thread has been moved to another dimension. So PM me with any needed info wanted.

CJ, I cannot access the thread, don't know why. I am definitely interested in getting a HEI module in 29mm for AT, and maybe 38 & 54mm as well. Contact Charlie O?
 
That's what I wanted for Xmas.....a CJim build thread!
Lotsa "reserved" posts waiting to be filled...nice.

s6
 
CJ, I cannot access the thread, don't know why. I am definitely interested in getting a HEI module in 29mm for AT, and maybe 38 & 54mm as well. Contact Charlie O?

Ditto, I'd be interested also and it says we "peon users" don't have privileges to access the link.

Kurt
https://aprs.fi/#!mt=roadmap&z=11&call=a/QCRS&timerange=3600&tail=3600

Apparently that thread has been moved to another dimension. So PM me with any needed info wanted.
from 1st post.LOl


As the build goes on I will show how I use & connect module to altimeter pyro for staging. Been using & tweaking the design for 2 yrs.

I have figured out how to turn I/S into av-bay. Requires 4in. bulk plates....# 6 threaded rod. [No need for heavy 1/4 in stuff]
Will use #4 for sustainer av-bay also. I got extra 38mm 6in. couplers to fiddle with, & one of those is a perfect fit from I/S to sustainer for coupling. The 7in. supplied is too sloppy/wiggly a fit for my taste. Although I will show how a bit of clear packing tape can turn it into a perfect fit.

I will use the 4in. diamter lip on I/S for switch wire/screw switch hole & put 3 vent holes for altimeter.


Once the Av-bay is made it will have the 38mm CR ,butting/glued a solid 4 in one. [Av-bay lid]
Need to drill separation charge hole into BP so wire can pass into 38 coupler.
This is almost identical to how I did the Sparrow-Arcus 1/3 scale. So I know it will work fine.

Need to bevel fins, make alignment guide & gather metal hardware along with sizing chutes & shock cords.
Telemega or RRC3 will do duty in sustainer & RRC2 or Strato in booster with Pet2 timer for separation charge.

I will probably mount NC bulkplate up into NC, rather than bottom of coupler, to net a few more inches of recovery space, which is only 7inches. I can get 9in. doing it this way. Stuffing chute, cord, nomex into 38mm tube,9in long is much better than 7!

I glue Kevlar recovery harness to outside of motor tubes & use 1/8 Kevlar in Sustainer & 9/16 TN for booster since there is a ton of space in there. 3/16 eyebolt in Sustainer...1/4 in Booster.
Going to use the 7in coupler for av-bay, since the extra 6in is perfect for I/S. I need more room in there for Tela & tracker anyway.


By the way for those that know me, here's a shocker :y:.... I bought a drill press AND calipers!!!@@@ Still keep my trusty 100yr old hand crank drill on hand...ya just never know :y:
Guess I'll move out of my cave, gonna miss that darn cave though.
BUT I still have that 10 yr old piece of sandpaper that's been used on every glass kit I made in those 10 yrs. Wish they still made that diamond dust/waterproof stuff!
 
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That's nice but does that mean they'll need be a separation charge or will drag separation be enough before the sustainer motor lights off? Nothing like returning with a melted gob of plastic on the booster.
Would want to avoid that. Kurt
 
It's actually for Charlie's carbon version of the Nike-Apache. It's beginning to grow on me though.
In any case there will be the 38mm coupler tube inside, whether Al or G-10....separation charge is inside that.
Sustainer will be at least a 2 sec. coast delay, before ignition.

Based on other versions I have done, it will separate like a boosted dart upon motor burnout, so no worries.
Also why a smooth, perfect fit is mandatory for me.
Top of I/S coated with high temp epoxy for further protection.
 
To do staging, I have replaced the standard forward closure with HEI [head end ignition] module.
Been using a 54mm CTI one for 2 yrs now. Threaded 4-40 rods and nuts. I use 2 matches for redundancy, tho must folks use 1.

For this project, smaller 29 versions are needed. For AT I use threaded ring from RAS system. Closure is 'floating copy of one that comes with the AT RAS system.

CTI 29 is identical to theirs & just drops in after removing O-ring from plastic one that comes with reload and putting it on my new HEI version.

Screen Shot 2017-12-16 at 11.42.58 PM.png DSCN0214.jpg

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Match sits above pellet in top grain, wire wrapped around rod and nut holds in place. CTI comes with pellet, AT I use my own. [or you can use Pyrodex pressed into top grain]
Have successfully made wire leads with 40ga nichrome [same size used in E-match] soldered to leads, attached directly to my BKNO3 pellet and lit with 9v battery. Tested with launch system also worked great, kinda surprised me, thinking that 12 v might have burned wire through to fast, but didn't!

MERRY XMAS EVERYONE!
 
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Much has happened since Xmas. I finally got camera back and the build will now begin back up at Post #1 where I deleted print and began a new. Check back soon for updates in the reserved posts.

Oh...by the way, another 2 stager I began by getting 2 Wildman Mach-2 kits during Black Sat.
54 minimun diam. scale downs of the 75mm "Falcon".

I'll convert one to a 38 motor for sustainer with a typical coupler I/S and leave the booster 54 min. These have been flown to M-2 on L-1000's just glue/fillets holding fins on.........teasers..... wicked little 4 fin beast for 80.00


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I just want to make a "Park Flier" out of these for fun.:dark: :lol:
 
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Are you going to make the model for the scale IS available on Thingiverse or something? It would be greatly appreciated by those of us that got the kit and are looking for something closer to scale!
 
Those fins aren't stock are they Jim? Beveled fins in a $80 kit?

Yes they come beveled in kit. But NOT like ones shown [mine], they were further refined to a sharper taper/bevel.

https://www.rocketryforum.com/showt...M-Mach-2-rocket-2-stage&p=1758046#post1758046

Are you going to make the model for the scale IS available on Thingiverse or something? It would be greatly appreciated by those of us that got the kit and are looking for something closer to scale!

The material is PETG. It should be further tempered/annealed at 185F, for 4hrs in curing oven. Dialed down to super fine filament diam. for great resolution. Coated with high temp epoxy before cure.

36+ hr print. Doubtful it will be available, person responsible[Charlie] spent days/weeks researching accurate scale drawings, then more days rendering it CAD. A few proto's, some mods to print files etc. finally a finished product.
More likely, may become a commercial venture of some sort down the road. But one never knows........
 
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Post #2
We have official start of build!
Back..up top ^.


Motor mount sustainer.
Kevlar Y-harness glued to MM tube.
Av-bay lids & fit.
 
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Post 3 above ^
More done today.

Give me a couple minutes to post after this one.

Glued in sustainer motor mount
Tacked on fins.

Well I got my extra's today...don't hate on me! More bedazzles fins for my Mach -2 rocket.
I had fins for booster made 3/8 larger all around for stability. I like larger fins on my booster than sustainer, when using same fin design. Sustainer fin atop booster fin for size.
Sweet ain't they...lol :y:
Ya can shave with these bad boys!

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I ran into a major issue with 29mm motor mount in sustainer.
I started to glue on motor retainer & a little birdie whispered in my ear.."better check the fit".
Boy am I glad I did! It don't.
I dry fitted retainer on, slipped into airframe, then tried to slide in the I/S coupler....OOOoooops it don't work!!!


Retainer won't slide inside the coupler. Has anyone else tried fitted any type motor retainer on theirs & got the I/S coupler to slide over it???

TIP:
No worries, I'll just friction fit smaller 29's & use my favorite trick for larger motors.
Measure length of MM.
Transfer that measurement to motor case, wrap several layers of masking tape around case.
Load re-load into case as usual, BUT leave off rear closure.
Drop in motor from front through motor mount, THEN screw on closure.
In essence you have captured motor in mount, can't go anywhere.

DSCN0359.jpg

You may have to use a dowel/PVC etc. to put some pressure on front of motor to hold in place while tightening closure/removing it. But I've been doing this for years just cause I'm cheap & don't want to buy retainers for every rocket.
 
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Post 3 above ^
More done today.
Give me a couple minutes to post after this one.

Glued in sustainer motor mount
Tacked on fins.

Well I got my extra's today...don't hate on me! More bedazzles fins for my Mach -2 rocket.
I had fins for booster made 3/8 larger all around for stability. I like larger fins on my booster than sustainer, when using same fin design. Sustainer fin atop booster fin for size.
Sweet ain't they...lol :y:
Ya can shave with these bad boys!

View attachment 336742 View attachment 336743



I ran into a major issue with 29mm motor mount in sustainer.
I started to glue on motor retainer & a little birdie whispered in my ear.."better check the fit".
Boy am I glad I did! It don't.
I dry fitted retainer on, slipped into airframe, then tried to slide in the I/S coupler....OOOoooops it don't work!!!

Retainer won't slide inside the coupler. Has anyone else tried fitted any type motor retainer on theirs & got the I/S coupler to slide over it???

TIP:
No worries, I'll just friction fit smaller 29's & use my favorite trick for larger motors.
Measure length of MM.
Transfer that measurement to motor case, wrap several layers of masking tape around case.
Load re-load into case as usual, BUT leave off rear closure.
Drop in motor from front through motor mount, THEN screw on closure.
In essence you have captured motor in mount, can't go anywhere.

View attachment 336741

You may have to use a dowel/PVC etc. to put some pressure on front of motor to hold in place while tightening closure/removing it. But I've been doing this for years just cause I'm cheap & don't want to buy retainers for every rocket.

I'm not sure what retainer you were trying to fit, but assuming it was not a GLR Slimline retainer, do you think the GLR would fit if it was slightly recessed?
 
I'm not sure what retainer you were trying to fit, but assuming it was not a GLR Slimline retainer, do you think the GLR would fit if it was slightly recessed?

I'm using a simple home brew sleeve with snap ring inside to retain motor.
Being recessed is not the issue. Mine is pretty darn thin. Don't see how an Aero-Pac Cap will fit either, someone needs to check for the group.

Why I asked for others input.

This is issue...lol

1.377 don't work with 1.374 It sticks tight,even Jethro Bodine can't make it go...lol
This was after sanding heck out of inside coupler & outside of sleeve.

DSCN0374.jpg DSCN0384.jpg DSCN0385.jpg

Don't have a GLR or Aero-Pac to check.

Wall thick of this one......

DSCN0373.jpg

Gap between MM tube and ID of airframe. [mine, who knows if rest are same.] Wall thick of my coupler for I/S. If it helps anybody else with this dilemma.



This is why I decided to go with friction fit and forget about this issue.
Those that fear friction fitting motors, will have to share their solution with us.DSCN0379.jpgDSCN0380.jpg
 
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I'm using a simple home brew sleeve with snap ring inside to retain motor.
Being recessed is not the issue. Mine is pretty darn thin. Don't see how an Aero-Pac Cap will fit.
Why I asked for others input.

This is...lol

1.377 don't work with 1.374 It sticks tight,even Jethro Bodine can't make it go...lol
This was after sanding heck out of inside coupler & outside of sleeve.

View attachment 336768 View attachment 336769


View attachment 336770

Don't have a GLR or Aero-Pac to check.

Wall thick of this one......

View attachment 336776

Gap between MM tube and ID of airframe. [mine who knows if rest are same.] Wall thick of my coupler for I/S. If it helps anybody else with this dilemma.

View attachment 336778 View attachment 336779

I'll be using friction fit for my snap ring cases on this. I'm also anticipating using head-end ignition. I'm also also anticipating leaving the Apache in the box and just flying the Nike as a motor test rocket...
 
Long wait is over. Post 4^

Assembly of I/S coupler!

What I figured most folks were waiting to see, how I utilized the inter-stage
It took quite awhile to figure out the steps, before starting, but it's finished!@#@:wink:

Dang there were a boatload of these things sold.
Where are some other builds, pull your heads out of the sand, 350 of them went out.
Someone must be building, beside me. Sure was a lot going on during BF sale, thought there would be more interest.
Seem like Forum attendance is waning?
Any one else getting that feeling.
Less & less build viewing.
 
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