Wildman jr. Fast Build

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dlb

Sky Pyrate...
Joined
Jan 24, 2009
Messages
1,283
Reaction score
141
OK
I'm building a Wildman Jr. and so are alot of others.
I wanted to sqeeze everthing I could out of it and max it out a bit.

I started with the AV bay.
parts added:
2) 1 1/2" U-bolt
1) 8" piece of all-thread and nuts, things
1) electronic mounting board and 1/4" mounting tube

below is a couple of pic's

AV1.jpg
 
Next comes the Nose Cone
This time I needed a place to add a Tracker for those "J" flights.
I mean it's out of site on a J350.
so my answers was build an internal bay.

added parts:
1) 38mm bulkhead, 7 ply 1/4"
1) 54mm bulk head
1) 54mm coupler bulkhead
1) 10-32 all-thread and hareware
1) 1 1/2" U-bolt

plenty of room for most anything and Strong

pic's below

NC1.jpg

NC2.jpg

NC3.jpg
 
Next the Motor Mount
OK , here I just could not glue in the shock cord in the mount.
I know I do it all the time , but this build is different and I wanted something changable and strong. Hard to do so on a 1/4 wide CR. I think I got it pretty well.

added parts:
1) 16" long piece of Carline cable 3/16" and clamps

the front end is glued ( cable side) .but not the AFT (for later reasons )

and the Pic (worth a thousand words)

MM1.jpg
 
And now the lower airframe

I installed the motor mount, but a note here, I use 40 grit and ruff up all areas within the airframe ( nice deep cuts, good for a great hold area ). use the aft CR to help center it correctly, but after it cured remove it.
Epoxy used was US Composites and some milled fiber.

Next I tacked the fins on, with just a small amount of glue along the root edge doing one at a time and checking for proper positioning.
You can see the glue joints inside.

the pics

fins1.jpg

fins2.jpg
 
Ok, time for the outside fillets, yes I said outside first
Notice that the aft CR is removed.
After the outside fillets are done, then the internal fillets will be done.

I use a very slow epoxy and mixed in 5/16 long milled Fiberglass and made a small fillet to each fin. Letting cure after each( 24 hours) then on to the next fin.

Pic's below

fins3.jpg
 
Now here's the reason I did not glue in the aft CR.
Being it's a small space and harder, adding internal fillets is not that bad.
Using Milled Fiberglass and a slow cure epoxy in a small Dixie I pour in the mix on one fin at a time, faced the fin down to cure overnight. did that on all 3 fins. Now I just have to add the aft CR and motor retainer.

These fins are ROCK solid.

fins4.jpg
 
Looking good. Nice small fillets. Too bad more fliers don't realize small fillets=light weight = higher flights.

Like how you did the NC for trackers.
 
I am just finishing up mine as well. This is the first fiberglass kit I have built. I really like it!

I built mine as the instructions stated, and drilled holes along each side of the fin slots to allow the epoxy/milled carbon fiber to be injected from a syringe. It was a little messy, and I probably ended up using more epoxy than your approach, but it worked out fine. Once I injected the epoxy and wiped up any external mess, I just slapped some tape over the holes and let it cure. When I removed the tape the next day, it was like the holes were never there.
 
I'm just finishing up the internal fillets on mine, as well.

Followed the printed instructions, but drilled a few extra holes along each fin edge, to make sure to get good coverage (the epoxy mix was fairly thick). Used West System epoxy mixed with milled fiberglass for the internal fillets. Injected about 10CC of the mix along each fin, and it did a great job of self-sealing the injection holes. The recommended technique may use a bit more epoxy, but those fins are going to be SOLID. :cool:

Another change was to replace the stock aft centering ring with one I turned from a scrap of 3/4" birch plywood. I wanted the extra thickness for added support because the motor tube needed to be moved rearward by about 3/4" to accommodate my motor retainer (PML HAMR-38). Because I didn't want the retainer recessed up into the airframe, there would have been a ~3/8" unsupported section of MMT between the aft CR and the retainer otherwise.
 
Last edited:
Did you guys glue your motor mount into place before you injected the epoxy?

I did. But as soon as I slid it into place, I started installing the fins. That way, if I needed to shift the motor mount slightly forward or aft, it would still be able to move.

When putting the fins in, I also used a syringe through the fin slots to lay a bead of glue onto the motor tube where the fin edge would touch, in addition to applying it to the root edge of the fin as per the instructions. Put the 3 fins into place, make sure they are aligned, and let the glue gel. Then I started injecting the internal fillets to lock everything in place.
 
Like it said in the instructions ( better way's to build a Mouse trap, we all have them .)

I like the aft entry for added uniform internal fillet, you can see it and know it's good.

Next I added the aft CR, and then the Aeropac retainer to top it off. Mine is completely outside the aft end and easy to access.

boy this is not fast as state in the header, but stong!!!

MR1.jpg
 
The external fillets on mine are finished (used West System 105/205 mixed with phenolic microspheres), and man is this thing SOLID! :) I guess this is how Wildman manages to give a lifetime guarantee on these kits.

How did the other builders handle the front fillet on the forward CR? I ended up drilling a hole just forward of the CR (opposite of the shock cord anchor point), and injecting ~5CC of epoxy, then taping over the hole until it set. The translucent airframe tube shows that it flowed out very well, and wicked down between the CR and the airframe in a few spots that the initial gluing seemed to have missed. This motor mount certainly isn't coming loose anytime soon. :)

Has anyone else weighed their booster section yet? Mine ended up at 1.75 lbs with the retainer and all the shock cord, prior to finish sanding. I probably used more epoxy than I really needed to, but I'm looking for strength/durability rather than every foot of altitude with this build. Planning to use it for my L1 cert, then convert it to carry my downlink video system.

What are other builders planning for launch lugs/rail buttons?
 
Last edited:
just weight it, a woping 662 grams or about 1.45 lb's.

:D
 
So, I guess red is the color for the booster section then Don? You DID remember to cut me a set too, right?<wink><wink>nudge, nudge...;)

My booster section weighs in at 1lb 11.3oz with the HAMR I found in my 'box of stuff' here in the rocket dungeon from Hades..lol....Picked up a really nice 48" flare chute off E-Bay for $0.99 that should do a good job as the main ;)

Need to do some work on it, but job lately has been sapping my energy/motivation..Hope to get some work done on it this week-knock on wood and wish me 'luck'..lol
 
How did the other builders handle the front fillet on the forward CR? I ended up drilling a hole just forward of the CR (opposite of the shock cord anchor point), and injecting ~5CC of epoxy, then taping over the hole until it set. The translucent airframe tube shows that it flowed out very well, and wicked down between the CR and the airframe in a few spots that the initial gluing seemed to have missed. This motor mount certainly isn't coming loose anytime soon. :)

I did exactly the same thing for my forward CR.


Has anyone else weighed their booster section yet? Mine ended up at 1.75 lbs with the retainer and all the shock cord, prior to finish sanding. I probably used more epoxy than I really needed to, but I'm looking for strength/durability rather than every foot of altitude with this build.

Sounds like we had similar builds. Mine is exactly the same weight with an Aero Pack retainer.

I really like this kit.
 
The translucent airframe tube shows that it flowed out very well, and wicked down between the CR and the airframe in a few spots that the initial gluing seemed to have missed.

One other thing... I used a bright LED flashlight in the motor tube occasionally. It really helps shows the internal fillets if you are using the syringe injection method.
 
Sweet decals Don
I hope you guys enjoy this kit as much as I have
I flew mine last week on a g skid and then a J350 in single deploy mode with a 9x90 streamer
Tim
 
Thanks Tim, there about 3 versions now, hahahahaha, one for Crazy Jim's 4" Wildman

here's a day light look at the fin can area, you can see the fillets on the CR's and Fins thru the fiberglass. Like I said Rock Solid, no J570 scares here.

Great Kit you got there!!!

then one total picture before Painting

MR2.jpg

RFP.jpg
 
After drilling the Rail Button mounting holes and a light sanding, it was time to Prime the booster section. I use Dupli-color gray filling/primer ( very sandable )

and also a picture of my High Tech Paint booth area.:eek: and it's portable!( bugs may be included)

fc1.jpg

Prime_lower.jpg
 
Last edited:
After drilling the Rail Button mounting holes and a light sanding, it was time to Prime the booster section. I use Dupli-color gray filling/primer ( very sandable )

and also a picture of my High Tech Paint booth area.:eek: and it's portable!( bugs may be included)

Where did you put your second railbutton I put mine into the centering rings?
 
Where did you put your second railbutton I put mine into the centering rings?

That is where I am going to put mine..One on the aft ring and the other on the front ring..Yeah, they are only like 4" apart but they will do the job..;)

Have attached the RS file(again)..lol..Originally I posted it in MY Wildman Jr build thread:eek:..I need to get to work on mine..soon..This weekend..:rolleyes:
Of course the normal disclaimer for the rocksim file; It was a hastily put together/measured and weighed approximation..You will need to adjust with the 'mass override' option for your OWN rocket in regards to the weight and CG location for accurate simulations...

View attachment Wildman Jr.rkt
 
Where did you put your second railbutton I put mine into the centering rings?

I opted to move the Rail button forward by 5.5" and add extra mounting by using a ground down Nut on the inside of the airframe.
this will be shown soon, after painting is complete and I mount them.
 
First layer of Black Paint.
then sanded with 600 grit

and a Close up about the second rail button, look close, if the hole appears to be threaded, it is.

P1.jpg

P2.jpg

p3.jpg
 
Back
Top