Building the Painkiller Max

[Rrwjr]

It’s been a while since I decided to do a build thread. I’m not sure what exactly made me decide to want to do one as I have seen that some people are rather harsh in their comments. Sometimes as a community we don't treat one another with the respect one deserves. I guess the last 6 months of trials and tribulations that I’ve been thru in my personal life have made me a stronger person and made me more sensitive to how I treat people.


I look forward to hearing any comments positive and even the not so positive. Believe me there are many ways that one could do this build and how I’m doing certainly isn’t the only way. The other thing I'll mention is that I really try to capture a lot of detail-even the simple steps as there was a time not too long ago when I was looking for some of the details that we take for granted but as someone newer to the hobby I didn’t know. So if some feel like I’m moving slowly, its OK take a breath and appreciate the things around you. You never know when those things may disappear.

The last thing I'll mention before getting started is that I usually try to do something different in each build and there are some things I do because I’ve done them before and I feel comfortable with it.

So the first thing I try to determine on a build or even buying a kit is what Ill plan on the uses for a particular rocket to be. This one was pretty easy for me. The looks of the kit on the BlastCap rocketry page just screamed sexy, it’s a 4.5 diameter kit something I don’t have and will fly on my current level 2 motors just fine at our normal field and as I get my L3 cert, I can air it out at some further away fields.

So with the introduction out of the way let’s get going on this thing.:clap:

I failed to take any pictures of the box and the way it was packed. It was top notch. Nose cone was wrapped in paper and set into the airframe so it didn’t get stuck, the fins and rings, and bulk plates were also nicely wrapped.

I laid everything out on my bench to inspect and was very impressed. Note- the Aeropak doesn’t come with the kit.



The next thing I do is actually take an accurate weight of each component and measure the ID and OD as well as length to tweak my roc-sim file. Ill mention here that Gary provided a nicely detailed roc-sim file to start with.




Next it was time to do some dry fitment on the rocket. I’ve bought and built quite a few kits. This kit went together easily for dry fitment, probably one of the best fitting kit I’ve seen right out of the box. Very nice quality.



I couldn’t help but start to imagine how this kit looked next to his little brother, so I had to do a quick dry assembly of it for a picture. Then I started thinking about 6 grain motors and I set a 6 grain case next to each one. That just looked cool. With that thought in mind I decided to move on to the next step.

 

[Rrwjr]

For this build I decided I would make (2) ½ thick birch ply centering rings. One for the front of the motor mount and one for the rear for motor retention. I started out in my trusty drill press with a single point circle cutter. After I got the center area cut out, it was off to the sander to tweak the fit to fit the motor mount.



After cutting the outside out I used the centering ring that came with the kit as a guide and adjusted the OD on the disc sander. This was possible since the centering rings that came with the kit were so nicely fit to the motor mount and airframe.



A final fit check and to the motor mount and airframe went well. So I had to make a second one for the back of motor mount.

 

[Rrwjr]

Next was a dry assembly to make sure everything was going to line up the way I wanted it to.



A quick double check to make sure I could easily grip the motor retention cap and it was time to go on to the next step

 

[Blastcap Rocketry]

Russ,
Looking forward to your build and thanks again for your purchase. In regards to the first part of your post, there is most definitely more than one way to build a rocket, this thread happens to be YOUR way, I would hope anyone reading it will respect that. Whether you've been building rockets for 10 years or 10 days, there is always something to be learned from one another.

 

[Rrwjr]

So here is a question for those following, should I use foam for the fins, internal fillet ejection, or reach in the back and put epoxy in the put rear centering ring on?

While we ponder how we will deal with attaching fins, we can sand centering rings and get some sub-assemblies started. We put some thick CA on the wood centering ring and attached the fiberglass ring to it. We added some clamps and set it aside to dry.



While that was drying it was time to insert the nose cone coupler and AV-bay into the back of the airframe to transfer some lines to add screws later on in the build.

 

[Rrwjr]

Now the centering rings are dry, we can now attach the 2 U-bolts we wanted to use for shock cord attachment. We needed to do a bit of grinding on the inside and outside of the metal base plate to keep the fit we needed on the motor mount tube.( I Need One Bad Hawk to recover to get some harnesses ordered).:grin:



Next I marked where the rings would need to be going- these areas were then sanded for epoxy adhesion.



I then tacked the middle centering ring into place with a bit of CA. I used the 4 boards ( all the same height) to hold the ring parallel to the bottom of the motor mount tube.

 

[Rrwjr]

After the ring was tacked I got my epoxy ready. I use West systems for internal items as well as chopped carbon fiber. This is how the epoxy looks when mixed up without the Chopped Carbon.





I mixed in the chopped carbon and here is how mine looks along with a syringe for applying.



I put a nice bead around the top ring and the top of the middle ring. Time to let them dry.

 

[Sevian]

Just curious, what grit of sandpaper do you use to sand?

 

[Rrwjr]

Just curious, what grit of sandpaper do you use to sand?

I use 60 or 80 grit paper for roughing up the areas i will be epoxying. Sometimes the pictures seem to show more sheen than is really there. If you follow the rest of the build thread as i complete it, you will see areas where I use a dremel and engrave "x"'s for better adhesion.

 

[Kehoes23]

Yes this kit is nice, looking forward to your build thread, I got the Painkiller 3 kit, on e of the first ones Gary put out, it's not done yet but I did start to paint it.

 

[Sevian]

I use 60 or 80 grit paper for roughing up the areas i will be epoxying. Sometimes the pictures seem to show more sheen than is really there. If you follow the rest of the build thread as i complete it, you will see areas where I use a dremel and engrave "x"'s for better adhesion.

Awesome! Can't wait to see how this turns out!

 

[Rrwjr]

OK back at it. With my sons sports, work, and other obligations, its been tough to find a large amount of time to just build. Thats ok, it gives me time to ponder all kinds if ideas.

Up next is the back centering ring which we will be attaching to the motor retainer. Again time to check fits. I started with just sliding the wooden center ring onto the back of the motor mount. I then use a 75mm 2 grain case and I slide it into retainer and then drop case and retainer into motor mount and bring the back centering ring flush to the back of the motor mount.



Once I saw everything was going to fit well, I then transferred holes from retainer to centering ring. (Sorry no picture of that). I then went over to my drill press and drilled 7/32 holes for the self-threading 6-32 screw inserts.



After all the holes were drilled, I tried threading in one of the inserts with a hex key. No problem, screwed right in. So I installed all of the inserts and then I drilled holes thru the fiberglass centering ring as the inserts were a touch thicker than my birch ply centering ring.

 

[Rrwjr]

As I inserted the screw, I had an idea. If I use a little bit longer of a screw I can then thread a nut on to the back of the fiberglass centering ring which then basically acts like a safety if the threaded inserts moved or loosened in the ply ring. Note in 3 areas I didn’t do this these are areas where fins and fin slots might come into play. Yes I know what some of you are thinking- over- engineered but I’m OK with it.



Side view shows the motor retainer cap on, the screws holding the retainer to ply ring and the nuts threaded onto the screws holding the fiberglass ring on



I then re-installed the motor mount into lower airframe and made sure nothing was protruding by fin slots and I used my scriber to scratch lines on the 3 fin slots, so I know where to sand and aligh motor mount when it is glued in.



After that step was completed I put another bead of epoxy with chopped fiber on it on the inside of the front ring where my U-bolts are at. Time to let that dry.

 

[Rrwjr]

Well normally i would mount my motor mount. I was hoping for some feedback on whether to use injected fillets, foam filled fin can, or pull back ring off and epoxy from back, Anyone have any thoughts? I haven't foamed a fin can for a while and i definitely haven't foamed something that will see large L motors as well as M motors.

 

[blackjack2564]

Inject....you should be a "pro" at it by now...LOL!


...... save the foam for speed builds.

 

[jeff2space]

Russ, just saw your thread tonight. Glad I did, great looking rocket. As far as as internal fillets on this model I would remove rear centering ring and do fillets. Injecting would be my second choice. I have never foamed, yet. Great build so far.

 

[Rrwjr]

Inject....you should be a "pro" at it by now...LOL!


...... save the foam for speed builds.

"Pro" - I'm not so sure about that. Although I have gotten better. With the green tubing it makes it easier to see when doing injecting.

 

[Rrwjr]

Russ, just saw your thread tonight. Glad I did, great looking rocket. As far as as internal fillets on this model I would remove rear centering ring and do fillets. Injecting would be my second choice. I have never foamed, yet. Great build so far.

Yes it is a cool looking kit- I couldn't resist. I havent come up with a color combo for painting it yet, but I still have a bit of time before im ready for that.

 

[Rrwjr]

Well I'm gonna go with injecting. I don’t have much time tonight but let’s see what we can get done. First I will scuff up the end of the motor mount tube and grind “x”s around the perimeter. I believe that helps with adhesion.



I then sanded down the body tube where the fins make contact with the motor mount. I like to do this versus just sanding the whole motor mount. I guess I’m a bit lazy.



I then did one last double check to see that my measurements were right and the fins fit snug in between the centering rings.



Everything looks good so it was time to epoxy on the motor retainer and I also put epoxy in the front of the retainer making sure to miss the areas where the fins will be attached.

 

[Rrwjr]

While the epoxy dries, I sanded the inside of the airframe with 80 grit paper. Hard to get a picture of your arm in the tube. After some sanding I had some nice grooves and roughed up area for epoxy to adhere to. Hopefully I will get motor mount in airframe tomorrow.

 

[ECayemberg]

Russ,

Doing great! It's looking really nice so far; hope to see it fly at Bong later this season!

Keep up the good work; I'm enjoying the build!

-Eric-

 

[Rrwjr]

Russ,

Doing great! It's looking really nice so far; hope to see it fly at Bong later this season!

Keep up the good work; I'm enjoying the build!

-Eric-

Thanks Eric. That means a lot coming from an accomplished builder such as yourself. I am hoping it may fly naked at Mini Midwest Power, just depends on the time I get to work on it.

 

[Rrwjr]

As happens with many of us in this hobby, life at times gets in the way. Such was the case for me on this build and thread but I’m glad to say that I finally was able to find time to get back to this kit. As `I left the thread I was getting ready to insert the Motor mount. I used West Systems epoxy with chopped carbon- this might be considered overkill by some but I do plan on flying this with a 6 grain XL 75mm once I have my level 3. One makes me wonder why I didn’t make this my L3 rocket



As the motor mount dries, it’s time to lay out a number of items on the airframe, Rail buttons, Av bay vents, airframe vents, 2-56 screw holes for shear pins, 4-40 screw holes to keep coupler attached to upper air frame. Once I have everything laid out on the airframes and coupler, it’s time for the next step.

 

[Rrwjr]

Making my fin guide. As most people do I got my layout from payloadbay.com. After printing it out I glues it onto a used sheet of plywood. I drew out my outer shape, I like many use the triangle. I then cut out my outside shape using my table saw. I decided I would try out my new drill press with a single point fly cutter to rough the center hole. It worked pretty well, so I thought for practice I would try to size out the center hole. It worked out quite well. Now how should I do the slots? Oh that’s right I have access to a full machine shop of tools with my job. So off to the mill I go to mill the slots. After I milled the slots, I decided to do a test fit. With everything fitting and looking good, it was on to my next step.

 

[Onebadhawk]

Wow,,
I didn't see this before Russell,,
You slipped this one by me...lol...
Absolutely smokin build man..
I told Gary T what a fantastic shape he has on his hands with the Painkiller line..
This is coming out fantastic already,,,
That whole I've got a machine shop at my disposal thing was a cheap shot man..
When I blew up the pic of you machining out a perfect fin slot I drooled all over my keyboard.. lol..
Talk about precision work..
I'm really jealous Russ...

I don't see why you wouldn't do your level 3 cert flight on this build Russ...

I sure hope I get to see this bird fly....

Teddy

 

[Rrwjr]

Since I was going to do internal fillets for my fins, I decided I would create some areas for my syringe to get a good flow going. I decided on 3 areas per fin slot.









I then drilled other holes I would be needing in my airframe, a 3/16 diameter vent hole in the lower air frame (below where the AV bay is) and above where AV-bay is. I drilled the rail button holes as well as the 2-56 shear pins holes thru the airframe and coupler. Even on a precision machine I still drill, tap, and set in a screw so I don’t lose alignment.












I also drilled a hole in the middle of the space that was between the forward centering ring and middle center ring to get additional epoxy on the center-rings.



As I dis-assemble the AV Bay from the lower airframe, I take time to enlarge the 2-56 tapped holes to a slip fit for the screws so I am only screwing thru the upper air frame.

 

[Rrwjr]

Before I tack the fins, in I must prep them. I find which fins fit in the slots best and number them. I then take a marker and marker a line along the fin so I know where to rough up the smooth surface of the fins. After that I grind grooves in them to help epoxy hold on to them. I then roughed up the outside of the airframe. Now its time to tack the fins in.

 

[Rrwjr]

I mixed up some Wests 5 minute epoxy for tacking the fins, I applied the epoxy –stuck them in the slots and brought my fin guide down over them. Time to let them dry.

 

[Rrwjr]

Wow,,
I didn't see this before Russell,,
You slipped this one by me...lol...
Absolutely smokin build man..
I told Gary T what a fantastic shape he has on his hands with the Painkiller line..
This is coming out fantastic already,,,
That whole I've got a machine shop at my disposal thing was a cheap shot man..
When I blew up the pic of you machining out a perfect fin slot I drooled all over my keyboard.. lol..
Talk about precision work..
I'm really jealous Russ...

I don't see why you wouldn't do your level 3 cert flight on this build Russ...

I sure hope I get to see this bird fly....

Teddy

Thanks for the kind words Teddy. I agree this kit has some real appeal. We just got a CNC lazer Engraver. I'm looking forward to how I can incorporate that into some future builds. I guess that's one of the benefits to being in manufacturing. Since I'm not on the floor anymore ( doing Technical sales/ program management) I still enjoy using the equipment when I can.

 

[jeff2space]

Hey Russ. Do you know what rail buttons you plan to use on the Painkiller Micro, regular 1010 or mini? I grabbed myself a micro. We'll need to drag race when they're both done.