MacPerformance Villain 3" build

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spowers42

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I am about to kick off my second high power build, and thought this would be a good time to try my hand at documenting the build. My hopes are that some of you more experienced people will be able to chime in with suggestions, as well as a reference for future builds. And maybe someone out there will also find it useful when putting together their kit.

My decision for the kit was to build something that can take me through level 2 as well as teach me dual deployment. I elected to go with the Villian because I like the looks, and wanted to try a phenolic build since my level 1 was a fiberglass rocket. In light of that I picked the 54mm motor mount, as this gives me the widest selection of motors, especially considering that I also got a 54 to 38 mm motor adapter. In addition to the stock kit I decided to also add a nose cone av-bay, as a secondary location for electronics such as trackers or things like atmospheric probes that I might wish to launch in the future. For retention I am using a boat tail style aeropack retainer.

For the first step I found the mass of all of the major subassemblies prior to construction. The mass will be obtained again once they are constructed, since the epoxy will add to that as well. But this gives me a rough starting point to modify the rocksim file so that I can determine what I will have to add as nose weight when assembling the nose cone. Additionally I used the fin slots to mark three lines on the av-bay coupler to aid in drilling holes later.

I have yet to decide on avionics at this point. I will be starting another build that will use the Raven and power perch, so suggestions on something different that can run off of 2 or 3 cell lipos would be great.

SAM_0187.jpg
 
Last edited:
DizWolf said:
I love my Villain. What do you have in mind for epoxy?
Click to expand...
I am using a combo of BSI 30 minute (nose cone assembly and small stuff) and rocket-poxy. I am waiting for the rocket-poxy to arrive. For the fin fillets and I will likely add some chopped carbon from some remnants I have laying around. What did you use?
 
Step 2:
The end of the nose cone coupler was cut at the first ridge per the Pinnacle nosecone bay kit instructions. The end was then made square and flush with an aluminum sanding bar. The two rings were test fit into the nose cone. After the test fit the attachment points were sanded per instructions, along with the ridge formed from the molding process. Following sanding the entire part was cleaned with denatured alcohol.

The av bay was assembled using BSI 30 minute epoxy (mixed by weight 1:1). The front bulkplate was affixed without any additional steps to the kraft tube, however the lower ABS part was sanded with 80 grit sand paper prior to attachment.
 
I got my Scorpion delivered this morning. I am impressed with the parts quality and fit. I thought it almost amusing that the kit was so "finished" it came out of the box almost fully assembled.
 
dixontj93060 said:
I got my Scorpion delivered this morning. I am impressed with the parts quality and fit. I thought it almost amusing that the kit was so "finished" it came out of the box almost fully assembled.
Click to expand...
Yeah, the tolerances on all the parts is pretty good. At first I was confused thinking that the motor mount was assembled, but it was just that tight of a friction fit. The Scorpion looks like a nice rocket. I was biased my decision by what was smaller, since I live in an apartment here in Boston.
 
spowers42 said:
I am using a combo of BSI 30 minute (nose cone assembly and small stuff) and rocket-poxy. I am waiting for the rocket-poxy to arrive. For the fin fillets and I will likely add some chopped carbon from some remnants I have laying around. What did you use?
Click to expand...

I did the whole thing with straight rocketpoxy. Some I dyed just to play with it. Didn't add any carbon to the fillets, for externals it'd get messy and hard to finish.

dixontj93060 said:
I got my Scorpion delivered this morning. I am impressed with the parts quality and fit. I thought it almost amusing that the kit was so "finished" it came out of the box almost fully assembled.
Click to expand...

I was really tempted to try and fly mine without glueing it up :) I sat there with the parts for a good five minutes going "OK, wash parts....nope...all clean. OK, Sand for the next 3 hours...nope, everything fits....ummm crap where do I start this thing???"

I didn't even use a fin jig. Just dropped them in.
 
Last edited:
DizWolf said:
I was really tempted to try and fly mine without glueing it up :) I sat there with the parts for a good five minutes going "OK, wash parts....nope...all clean. OK, Sand for the next 3 hours...nope, everything fits....ummm crap where do I start this thing???"

I didn't even use a fin jig. Just dropped them in.
Click to expand...

Given the way the aft CR is designed I'm guessing if you tacked the fins in with 5 min epoxy you could have just launched it.
 
dixontj93060 said:
Given the way the aft CR is designed I'm guessing if you tacked the fins in with 5 min epoxy you could have just launched it.
Click to expand...
The aft CR is one of the things I have to change to use the boat tail aeropack retainer though. Still going to be a strong build.
 
spowers42 said:
The aft CR is one of the things I have to change to use the boat tail aeropack retainer though. Still going to be a strong build.
Click to expand...

True, but the aeropack tailcone has the same effect. It's notched to fit inside the body tube, and will act as a thrust ring. I've got one on my 3" DarkStar :) can't lose.
 
I haven't been able to figure out how the Aero Pack tailcone retainers actually work. I'm familiar with their standard retainer which has the large threaded ring at the end that threads over the base part, and I've used Slimlines, both in the snap-ring variety and the one with the threaded ring that threads inside the retainer base's outer thread. What are the fixed and removable pieces in these tailcone retainers? Is the tailcone just a different form of the large threaded ring (perhaps even using the same base part?), or is there a ring that threads inside the tailcone part like the Slimlines, or is it something else? With the normal Aero Pack retainer there's a fairly thin metal lip on the base that you butt up against the motor mount and the casing's aft closure butts up against this, so the motor is only slightly farther back then if there was no retainer. It's not clear to me whether these tailcone retainers cause the aft closure to sit farther away from the motor mount end or if the motor just goes farther into the retainer than the standard one.

Aero Pack's website also mentions that "Cones Can Be Used On More Than One Rocket To Save Cost", which left me really confused as to what attaches to the rocket and what can be reused, before seeing that statement this weekend I had assumed the cone itself was the permanently-attached part and there was just a ring that threaded on the inside to capture the motor's aft closure. I had also assumed that using one of these retainers bought you another inch or so of motor length by shifting the end of the motor back to the end of the retainer (as with the standard retainer), but I'm now starting to doubt that this is the case?

I debated getting the 3.9"-to-75mm tailcone retainer for the Punisher 4 I ordered this weekend, but wanted to have a better understanding of how it works first, also wasn't totally sure it would be the right size for the "4 inch" body. I also couldn't decide between anodized or aluminum. :)
 
spowers42 said:
The aft CR is one of the things I have to change to use the boat tail aeropack retainer though. Still going to be a strong build.
Click to expand...

Using the inner step in the aft CR as a guide, grind/sand off the outer lip of the ring. When you finish your inner fin fillets, apply epoxy to the motor tube OD close to, and on to the end of the fins and slide the ring over the motor tube and up against the back of the fins. This will add additional strength to the fins and leave you the perfect amount of space inside the air frame for your tail cone retainer to set.

Mike Crupe
MAC Performance Rocketry

FLY CANVAS!
 
woferry said:
I haven't been able to figure out how the Aero Pack tailcone retainers actually work. I'm familiar with their standard retainer which has the large threaded ring at the end that threads over the base part, and I've used Slimlines, both in the snap-ring variety and the one with the threaded ring that threads inside the retainer base's outer thread. What are the fixed and removable pieces in these tailcone retainers? Is the tailcone just a different form of the large threaded ring (perhaps even using the same base part?), or is there a ring that threads inside the tailcone part like the Slimlines, or is it something else? With the normal Aero Pack retainer there's a fairly thin metal lip on the base that you butt up against the motor mount and the casing's aft closure butts up against this, so the motor is only slightly farther back then if there was no retainer. It's not clear to me whether these tailcone retainers cause the aft closure to sit farther away from the motor mount end or if the motor just goes farther into the retainer than the standard one.

Aero Pack's website also mentions that "Cones Can Be Used On More Than One Rocket To Save Cost", which left me really confused as to what attaches to the rocket and what can be reused, before seeing that statement this weekend I had assumed the cone itself was the permanently-attached part and there was just a ring that threaded on the inside to capture the motor's aft closure. I had also assumed that using one of these retainers bought you another inch or so of motor length by shifting the end of the motor back to the end of the retainer (as with the standard retainer), but I'm now starting to doubt that this is the case?

I debated getting the 3.9"-to-75mm tailcone retainer for the Punisher 4 I ordered this weekend, but wanted to have a better understanding of how it works first, also wasn't totally sure it would be the right size for the "4 inch" body. I also couldn't decide between anodized or aluminum. :)
Click to expand...

The Slimline tailcones are single piece and are permanently attached to the aft airframe and motor mount. The Aeropack on the other hand is only permanently attached on the motor mount and the whole tailcone screws on/off to insert the motor. Both systems require the MMT positioned out the back end of the airframe.
 
mike2wander said:
Using the inner step in the aft CR as a guide, grind/sand off the outer lip of the ring. When you finish your inner fin fillets, apply epoxy to the motor tube OD close to, and on to the end of the fins and slide the ring over the motor tube and up against the back of the fins. This will add additional strength to the fins and leave you the perfect amount of space inside the air frame for your tail cone retainer to set.

Mike Crupe
MAC Performance Rocketry

FLY CANVAS!
Click to expand...

Exactly what I have planned.
 
I foamed the fin can of my Scorpion and enjoyed the experience. I think that rocket could free fall from 2000 feet and not dislocate a fin, not that I want to prove that. :grin: I also plan to foam the fin can of my Radial Flyer once I get it.
 
I'm anti-foam and pro heaping mounts of epoxy. But that's just a personal thing. I may foam the nose on mine, not sure yet.

With the aeropack tail cone you've got to be careful with spacing. Space it with a motor installed, it can be different with some snap ring cases. When you install the MMT, make sure to at least slide the retainer assembly on to check for a gap. When I did my darkstar I had everything on the MMT glued up and installed the unit as one. Won't work if you want to leave the rear cr off and get at the fins for internals.
 
My rocketpoxy showed up while I was away on a business trip, so it is now time for this project to start back up again. All of my simulations showed that I was fairly good without adding nose weight, and if I have to I can still add some inside the nose cone payload bay. So I am proceeding without adding any at the tip of the nose. Last I left off the nose was setup ready to go, with the locations for glue joints roughed up with sandpaper. Today I am going to attach the forward centering ring for the nose cone av bay. First step is to clean the nose with isopropyl alcohol. Following that the epoxy is mixed 1:1 by mass. I then inserted the centering ring in the nosecone sideways nearly as far as it could go. Once that was out of the way, I put a bead of epoxy just past the lip of the nose cone. Then I pulled the ring into position on that lip and held in place until it was fairly secure.
 
I finished the nose code the other day, with rocketpoxy for all of the joints connecting the av bay to the cone. It is different to work with than the other epoxies I have used, but in general I like it. The bay itself went together really well, and is a feature that I might add to future projects. The next step is to assemble the motor mount. The first part of this requires sanding down the aft centering ring so that it can be slid into the body instead of acting as a thrust plate on the rear of the rocket. The aeropack retainer I selected will perform that function instead.
SAM_0189.jpg
 
Motor mount assembly:
1: After sanding the aft centering ring I did some test fitting of the aeropack. I found that it is a bit tight in the aft of the rocket, so sanded a bit of that until it was possible to twist it, as will be required to install and remove for flights.
2: mark the rear of the motor mount tube at 0.74". Then test fit and adjust that mark so that the retainer seats fully.
3: mark the fin location using a drafting pencil, or measure from the mark created in 2 to the top extent of the fin slots.
4: assemble the forward centering ring using rocketpoxy per the instructions.
 
This project has been sitting around a bit due to a hecktic schedule, but last night I spent some time working on assembling the AV Bay. During my initial prep when I received the kit I marked the tube using the fin mounts to have evenly spaced guides. After sanding around the center of the coupler and the inside of the av bay ring I found the center point of the coupler and marked around it using the small ring as a guide. From that point I measured the size of the ring and marked half that distance from the center in both directions. I marked around the coupler at those locations. On one side I also wrapped a layer of blue tape to prevent epoxy from getting squizzed out onto the the rest of the coupler. The center band/ring was affixed using a generous spread of rocketpoxy on the coupler tube.

Once that set up 3 holes were drilled using a 5/32" bit. I then used a 1/2" bit to debur the holes.
 
I haven't done a great job keeping up with posting stuff, but I am getting near the completion. I should be ready to fly by the next CMASS launch. I have completed airframe assembly, mounted a MissleWorks RRC3 altimeter, built an Eggfinder tracker, and started on the paint job. My intent is to do the first flight on an I motor, using dual deployment but keeping the motor ejection as a backup for the drogue. The chutes are on order, with a 48" spherachute for the main.

I will post pictures later today, but any advice on a first DD flight would be much appreciated.
 
Bat-mite said:
What kind of advice are you looking for?
Click to expand...
I guess stuff to double check. Also, for loading the charges that is done at the pad generally right?
Also I might do my level 2 at the same launch. Is it better to go back to single deployment if the field is large enough? I am running tracking as well, so that should help with finding it.
 
spowers42 said:
I guess stuff to double check. Also, for loading the charges that is done at the pad generally right?
Also I might do my level 2 at the same launch. Is it better to go back to single deployment if the field is large enough? I am running tracking as well, so that should help with finding it.
Click to expand...

No, not at the pad.

Here's what I do.
  1. Test and install your batteries.
  2. Test and install your e-matches.
  3. Slide the sled into the coupler, attach leads, tighten bulkheads. (Actually, leave the wingnuts a little loose until the bay is in the tubes. This helps align the bulkheads. Then remove one end and tighten.)
  4. Turn on alt(s) and listen for battery voltage and continuity beeps. Turn off.
  5. Load BP in wells, stuff with dog barf, masking tape over everything.
At the pad, all you do is turn on the alt(s), after the rocket is on the pad and vertical, but before putting in the igniter.
 
Today I printed a sled for the nose cone av-bay, that will hold a 250mah lipo and Eggfinder GPS tracker. SAM_0208.jpg

I also installed 4 plastic rivets to join the av-bay to the forward/payload tube. Additionally I have installed 3 shear pins between the av-bay and lower section, and between the upper section and nose cone.

I decided to use terminal blocks for connecting the ejection charges. I went back and forth on this for a while, but considering I intend to do many flights on this airframe, I figured it would be worth it to have things more convenient. It is another point of failure however.

Does anyone have opinions on using a deployment bag? I picked one up thinking it might be nice to have a more gentle and controlled deployment of the main, but I wonder a bit if it is just adding too many new things to the situation.
 
SAM_0210.jpgSAM_0211.jpgSAM_0213.jpgSAM_0214.jpg

Ready for its big day. Have to double check CG with the actual motor and make sure I don't need to add nose weight.
 

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    SAM_0212.jpg
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spowers42 said:
View attachment 290829
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Is that Dupli-Color Effex, or something else? I've planned to paint a rocket in Effex, but was just starting to wonder if it actually has metal in it and if it might block/attenuate the tracker's RF signal (and or GPS signal). I had test-painted a tube that an AT DMS motor came in, guess I need to stick my Eggfinder in it and do some range testing. :)
 
woferry said:
Is that Dupli-Color Effex, or something else? I've planned to paint a rocket in Effex, but was just starting to wonder if it actually has metal in it and if it might block/attenuate the tracker's RF signal (and or GPS signal). I had test-painted a tube that an AT DMS motor came in, guess I need to stick my Eggfinder in it and do some range testing. :)
Click to expand...

It is Spaz Stix holographic. I don't actually know if it has any metal in it. While I have a tracker in there it is more to learn to use one than necessity at this point. Let me know what your findings are though, could be important.
 
Checked the weight on everything and it is coming in at ~2.5kg. Seems a tad heavy to me, but maybe someone with more experience will correct me. The lower section (booster) itself with recovery stuff is about 850g. I may have been heavy handed with the rocketpoxy.

I used 1/4" quicklinks to attach recovery harnesses, is that overkill on this build? Maybe there is a link to some force calculations for recovery devices, I am more use to the world of dynamic load in KN from climbing. Thus I tend to overdo it with these things rated for static load working limits. I am running the 20' long harnesses from Mac Performance. Again, maybe overkill.
 
Big learning experience in this build is that the nose cone is probably best saved for last. I double checked all my simulations with motors I am likely to run next weekend, and determined that a good bit of nose weight was a good idea. I had drilled a hole in the top of the nose cone av-bay so that the antenna of my egg finder could fit through. So I was able to get a bunch of lead pellets through there. Luckily I had some syringes and PML expandable foam around, and was able to get enough through the hole plus some drops of water to seat everything in place. In no way is this an ideal situation, but I would rather be a bit more stable than accidentally fly something unstable.
 

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