Green Jello's Level 1 Build - Wildman Jr. Kit - "Certify With Us" program

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Green Jello

Green Jello

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Hello all! Yesterday I was fortunate enough to be chosen for the TRF/CTI "Certify With Us" program to get my HPR Level 1. Thank you so much to troj and Jeroen for choosing me. I have two kids and this hobby is hard enough on the wallet. This will help a great deal.


The Project:
After endless debate with myself, I ended up choosing the Wildman "Wildman Jr." for my kit. I chose it because it's a bulletproof all fiberglass model that can take a beating in the hard Nevada desert where I launch. I am very well experienced with LPR builds and techniques, but this will be my first fiberglass HPR kit, so it will be quite a learning process. I plan on doing the kit as a dual deploy setup and will most likely purchase the Adept 22 as my first DD controller.


The Build Plan:
I live in the high desert of Northern Nevada. It has been in the single digit temps for nearly 2 weeks now. As a result, my building area (the garage) is quite cold. So this may go a little slower than I'd like, but working with paint and epoxy just doesn't work in these kinds of temps. I hope to use this problem as a positive though. I can do the build slowly over the Winter and early Spring using all of you here at TRF for my endless noob questions.


The Launch Plan:
I will be attending LDRS in July out at Black Rock. This will be my second national launch after I went to XPRS last September. I hope to do the L1 certification flight there. To keep things simple, I will probably do the cert flight with the rocket in "short mode" and just use motor eject. Combining my first HPR and DD flights all in one doesn't sound like a very good idea :) I'm not 100% sure of what reload I will be using for the flight yet. That will be one of the many things you guys can help me decide.


Open Build Questions:
I'll just keep an updated list here of all the open issues I currently have and need help with.
  • What 38mm CTI reload should I use?
  • What shock cord and lengths should I use?
  • What parachute sizes?
  • Paint scheme?
  • Where to put the top rail button?
  • How to bevel the fins?

Special Thanks:
There are so many of you here at TRF who have helped me with all my questions and gotten me to this point and I thank you all. But there are a couple of people who have really gone above and beyond and I wanted to call them out:

  • Jeroen - Jeroen Louwers - For sponsoring this great program.
  • Fdog - James Flenner - For being my local Reno encyclopedia of endless knowledge
  • blackjack2564 - Crazy Jim Hendricksen - For his Black Pearl thread
  • Worsaer - Bill - For his kind donation of fiberglass and epoxy syringes
  • luke strawwalker - For answering so many of my questions with his 5000 word essays
  • WILDMANRS - Tim Lehr - For making awesome kits and providing great customer service
  • troj - Kevin Trojanowski - For choosing me for this program and moderating this awesome place

Well...that about does it. On with the build I guess.....
 
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Here is the first picture I have. All the parts laid out after their bath. My 4 year old asked me why the rockets get to take a bath and he has to take showers.

IMG_3537.jpg
 
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Congrats on the selection into the program, David! I know you'll make us proud here in Reno.

All the best, James
 
Congratulations on being chosen for the CTI "Certify with us" program! Since I just finished my DS Jr., I hope I can help you with some of your questions. I just weighed my Jr. and it's still just under 5 lbs. with only a few tweaks to the avbay and the decals before it's finished. In "short" mode it's about 3 lbs. I like your idea of flying it with motor ejection for your cert. flight, less preparation and less weight. The best way I have found to select motors for a rocket is with "Thrustcurve.com". You can just input the data and weight for your rocket and it will calculate what motors will work and tell you some of the performance characteristics for each motor. I have flown the Pro 38 H120 Red lightning several times with my Nuke Pro Max and really like it's performance and looks.When you get your Jr. finished and weighed, you can use Thrustcurve to help you make your motor choice. I used CJ's stock Blackstar build for a lot of answers to my build questions, and Wildman Tim is also a great resource for help and easy to talk to on the phone.
Good luck and I hope that I can be there at LDRS to watch your cert. flight.
 
Green Jello said:
I will be attending LDRS in July out at Black Rock. This will be my second national launch after I went to XPRS last September. I hope to do the L1 certification flight there. To keep things simple, I will probably do the cert flight with the rocket in "short mode" and just use motor eject. Combining my first HPR and DD flights all in one doesn't sound like a very good idea :) I'm not 100% sure of what reload I will be using for the flight yet. That will be one of the many things you guys can help me decide.
Click to expand...

I would recommend that after the L1 flight you do a DD flight either on a HPR motor or on an MPR motor that you could not fly prior to getting your L1 - say a G185? Fly the DD attempt with your main in the drogue position and nothing in the main position other than a small chute protector or something like it - then you can see if the deployment sequence works without any risk. Fly motor backup on the main with your motor ejection set to be a second or two after the electronics.

Green Jello said:
I'll just keep an updated list here of all the open issues I currently have and need help with.

  • What 38mm CTI reload should I use?
  • What shock cord and lengths should I use?
  • What parachute sizes?
  • Paint scheme?
Click to expand...

Color scheme, conditions and personal preference are going to influence your motor choice. Personally all of the options are good but Smokey Sam, Skidmarks, and White Thunder all make good L1 choices due to the dense smoke and easy tracking in the sky.

Shock cord type/length etc will be dictated by what you like and use more than anything else. Kevlar is popular for at least the anchor but fishing lead lines also work. I'm partial to really small bulltape Kevlar but a lot of people hate the stuff. Loads of people love nylon.

Length - depends on what you can cram in there - the smaller the cord the longer I'd go just because you can. I like to use 20-30' in between each section when I can, but practicality sometimes intervenes and I use whatever seems appropriate.

Parachute size will depend on space available and weight of the finished product and what you are willing to buy or make. I like very soft very thin material that packs tightly and opens quickly - some people like really heavy bulletproof chutes that are much harder to pack but could open behind a Ferrari and not shred.

Good luck!
 
Green Jello said:
Special Thanks:
There are so many of you here at TRF who have helped me with all my questions and gotten me to this point and I thank you all. But there are a couple of people who have really gone above and beyond and I wanted to call them out:
Click to expand...

Let's not forget Jeroen Louwers at CTI, without whom this program wouldn't exist!

-Kevin
 
green jello, should fly a green certification motor, alls im sayin is all... I would go with a full I motor.
 
Subscribed....looking forward to learning from your build and the advice you get. I have a DS jr that has had a bath but nothing beyond that: waiting for a free afternoon/evening.

Reading the instructions, it looks pretty straightforward. One thing I'm worried about us getting the CRs in the right spots to snugly fit against the fins. It seems that whenever I measure something like that, there's always some error/play.
 
Sully said:
Subscribed....looking forward to learning from your build and the advice you get. I have a DS jr that has had a bath but nothing beyond that: waiting for a free afternoon/evening.

Reading the instructions, it looks pretty straightforward. One thing I'm worried about us getting the CRs in the right spots to snugly fit against the fins. It seems that whenever I measure something like that, there's always some error/play.
Click to expand...

If you go back to CJ's build thread, he covers CR's pretty good about post #145. Tim does a pretty good job in the instructions, but it was a little confusing to me until I went back over CJ's thread. CJ sets the rear CR in place and uses the fins to set the gaps going forward. No measuring, just set the fins in place and tack the CR's with ca glue. I think the old plywood CR's were easier to work with, but if you sand out the fiberglass rings and keep them snug to the MMT, it works pretty good. This is only necessary if you plan to inject your internal fillets, which is the way I did mine, and they are hella stout!
 
troj said:
Let's not forget Jeroen Louwers at CTI, without whom this program wouldn't exist!

-Kevin
Click to expand...

Oh of course. I just didn't think he used these forums. Is there a way I can contact him to thank him personally?
 
Oh I already have all the chutes I'll need. I have nylon stuff from Fruity, Rocketchutes.com and Top Flight ranging in every size from 12" to 48". Later on when I get the final weight, all I have to do it choose the size.
 
Congrats David!!!

I wish you the best of luck and know your gonna do just fine!!

My kids are a bit older, 7 and 15...

David
 
I vote for an I800 VMax. Although if you want to actually SEE the cert flight, this is probably a poor choice. :dark:

Congrats, and have fun with it!
 
DISCLAIMER:

The following build thread is a log of the steps I took to build my Wildman Jr. kit. It should be taken purely as a documentary of the process I took, and NOT as high level expertise on how to build a HPR fiberglass rocket.

Thank you.....​
 
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PROJECT START

Parts Involved:
- All Fiberglass Kit Parts

Other Supplies:
- Sandpaper 220 Grit
- Sandpaper 100-150 Grit
- Dish Soap

Step 1 – Wash the Parts: After opening the shipment and making sure all the parts were there, the first step was to give everything a bath. I was really surprised at how much fiberglass dust comes on the kits and how irritating it can be on the skin. Also if you try to stick parts together while this dust is on them, they don’t fit well and can get stuck. The wife found it very strange that I was giving my new toy a bath in her Jacuzzi tub, but she left me to it. I just did some light scrubbing with dish soap and a kitchen sponge on all parts.


Step 2 – Sand Down Major Imperfections: The cuts from the manufacturer leave a lot of rough edges and burrs. So I sanded these all down with some 150 grit sandpaper until smooth. I was able to do most of it just by rubbing the ends on the sandpaper in a circular motion on a hard flat surface.


Step 3 – Total Body Sanding: As per the Wildman instructions I next sanded the entire kit lightly with 220 grit sandpaper.

Step 4 – Bath 2.0: After doing all that sanding, I had to pretty much do all the washing all over again. I wish I had thought of that beforehand. :mad:

Step 5 – Dry Fit All Parts: Once everything was clean and dry again, I dry fitted all the parts to make sure everything fit well. It was at this point I really could tell how nice fiberglass was going to be to work with and the overall quality of Wildman kits.​
 
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NOSE CONE ASSEMBLY

Parts Involved:
- 1x Fiberglass Nosecone with Aluminum Tip (Kit)
- 1x Fiberglass Shoulder (Kit)
- 1x Small Coupler Bulkhead (Kit)
- 1x 1/4-20 Threaded Rod (Hardware store)
- 1x 1/4" Flat Washer (Hardware store)
- 1x 1/4-20 Hex Nut (Hardware store)
- 1x 1/4-20 Lifting Eye Nut (Fix Find via eBay)

Other Supplies:
- 60 Grit Sandpaper
- 150 Grit Sandpaper
- Xacto Knife
- Long #3 Phillips screwdriver
- 7/16” Open End Wrench
- 5 Min Epoxy
- 2x 1/4-20 Hex Nuts
- 1/4-20 Wing Nut

I really liked the way Jim did his glueless nosecone for the Black Pearl. It accomplishes quite a few things. You can open up the nose cone and use it as an electronics bay for things like GPS trackers. You can always take the aluminum tip off whenever you want this way, and it also seems to be a stronger way to mount the eye. This way the pulling force on the eye is transferred up to the tip and not just pulling on the bulk plate. On top of all this, the extra hardware adds a small amount of nose weight if that is something you want. I didn't feel like taking the time to order another airframe bulkplate, so I just decided to make that end permanent and just make it so the shoulder was glueless and can be removed.

Step 1 - Remove the Aluminum Tip: Simply grab your large Phillips or slot headed screwdriver and loosen the screw holding the tip in place and take it off. The tiny fiberglass centering ring, may or may not be wedged in there. Save the screw from the tip as it becomes useful later.


Step 2 - Attach the Threaded Rod: Screw the 1/4-20 threaded rod into the nosecone tip. If need be, you can use some pliers on the middle threads to get it tight because they won't ever be used if you damage them. There has been discussion on whether or not some threadlock would be a good idea here. I didn't bother.


Step 3 - Sand and Prep Shoulder / Bulkplate: Next I took some medium grit sandpaper and smoothed the edges of one of the small bulkheads until it fit perfectly snug in the nosecone shoulder. I attached the screw I removed from the aluminum tip with a hex nut to give it a handle while working with it. Once it fit inside the shoulder perfectly, I roughed up all the surfaces that would be epoxied with the 60 grit sandpaper. After that I used an Xacto knife to score deep lines into them to get an even better surface.


Step 4 - Epoxy Bulkplate to Shoulder: Mix up some of the epoxy of your choice and attach the bulkplate to the shoulder. I applied a thin layer to the inside of the shoulder and then once the plate was in, I used the rest to make an internal fillet. Since this will never be seen, looks don't really matter as much as strength. Wait until the epoxy is fully cured the next day.


Step 5 - Assemble Nosecone: Once the epoxy is cured, you can tighten up the hardware to complete the assembly. I chose a larger fender washer, but I'm not sure if it adds anything over a standard one. I found that a wingnut was handy to hold things together while you are playing around with things. The final thing to do is cut the threaded rod to length. A common hacksaw will work, but a Dremel tool with a cutoff wheel makes a nice clean cut. I cut it twice. Once to get it close to the length and then a second time once I could put the eye nut on and get it exact.




Optional:
- One easy way to add a small amount of nose weight is adding a bunch of hex nuts to the threaded rod

- If you want the nosecone to be completely glueless, you will need to acquire or make an airframe bulkplate just like the ones you will assemble for the payload bay endcaps.
​
 
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First off-congratulations on being selected in the Certify With Us program!:clap:

Nice choice in rocket! I really like my Wildman Jr, one of my most flown rockets in the short time I have had it! Just a couple of thoughts and how I did mine:

Shockcords: I use 1/4" tubular nylon, 15' for the drogue and 10' for the main. Made a 'Y' harness and attached to sides of motor tube.
Main chute size: I usually use a 36" for the main, I go drogueless..

Oh,and no need for nose weight. Even in the short configuration. Have flown mine in the shorty mode on an H with no nose weight. Went straight as an arrow!

Continue on with the most excellent build!
 
Green Jello said:
Step 4 – Bath 2.0:After doing all that sanding, I had to pretty much do all the washing all over again. I wish I had thought of that beforehand.
Click to expand...

Trust me, you want to do it in the order you did -- the dust on them from manufacturing will make you itch something fierce. For days. From the bag to the tub, then do what you have to, then wash it again.

-Kevin
 
Pantherjon said:
Shockcords: I use 1/4" tubular nylon, 15' for the drogue and 10' for the main. Made a 'Y' harness and attached to sides of motor tube.
Main chute size: I usually use a 36" for the main, I go drogueless..
Click to expand...

Where do you find 1/4 tubular nylon? It seems like everywhere only goes down to 9/16".
 
I found some 1/2" tubular nylon at Sports Chalet and used it extensively in my Coppertop and DS Junior. 29 cents a foot and (theoretically) rated to 2000 lbs. No markings on the spool that held it, so I did a search on 1/2" TN and found info there. REI also carries an assortment of the stuff, but you are right, nothing under 9/16". I did a google search and found this site:
https://www.strapworks.com/Flat_Nylon_Webbing_p/fnw12.htm
They carry 1/2" and 3/8" webbing, but I have no experience with this company.

edit: OK, seems we are on the same page here.....

another edit: I also found some at the Rocketry Warehouse:
https://rocketrywarehouse.com/index.php?cPath=33_41&&page=1



 
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Here's a question for you owners of the Wildman Jr. (or similar). What did you do with the beveling of the fins? I was thinking of airfoil.

Or should they have the leading and trailing edges the same like the Darkstar?
View attachment 113107
Image courtesy of Jim Hendricksen
 
Green Jello said:
Here's a question for you owners of the Wildman Jr. (or similar). What did you do with the beveling of the fins? I was thinking of airfoil.

Or should they have the leading and trailing edges the same like the Darkstar?
View attachment 113107
Image courtesy of Jim Hendricksen
Click to expand...

i would use 1/4" kevlar for shock cord, because it packs nicely. (less bulky than nylon.) its what my son and I use on our darkstar. its cheap, and that means after a dozen flights, you can replace it for 4.00.
For the fin beveling, use a dremel with a sanding drum and make a 10degree(ish) bevel. bevel the LE and TE for drag reduction. the 3/32 fin thickness has a few layers of glass, so you can use that to make sure your bevel is consitant.
a router with jig also works but use a lubricant on the G10 so the carbide doesnt burn up in .01 seconds....

If you use wet sand paper, wetting the fiberglass, makes sanding much more pleasant.
 

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