Wildman Mach 3

[ksaves2]

Very nice. I wouldn’t worry about the weave either and the paint is going to be ablated if it’s subjected to Mach 3 I expect. That will give you another chance at refinishing in another paint scheme if you desire. Only thing I’d be worried about is if the CF would start to delaminate off the leading edges of the fins. The paint certainly is going to go bye bye if the rocket remains at high speed for very long. I remember Robert DeHate had some pictures posted of a project that was above Mach 2 ish for nearly 30 seconds. Nearly everything was stripped off the airframe after recovery. Paint, stickers and the leading edges of the fins laminated covering was really chewed away. I think it was of conventional construction using G10 and laminated fiberglass as it was over 13 years ago I saw the pictures online. I suspect CF would resist aerodynamic heating better. Good luck and I hope you “don’t“ succeed at turning everything back to elemental carbon! Kurt Savegnago

 

[crossfire]

Justin look luck on the trip. You might need a tent.

 

[DAllen]

Can't wait to see this in person.

 

[rfjustin]

29,108', perfect flight other than long distance recovery to the east. Took an easterly dip off the rail, but nice clean burn. Airfest was a hoot.

Preston of Top Flight Recovery:

 

[ksaves2]

What did the after photo look like and what speed was it able to achieve! Kurt

 

[crossfire]

Is that black ring on the back end the motor closure? Just looks differant.

 

[rfjustin]

What did the after photo look like and what speed was it able to achieve! Kurt

Other than some dirt and smoke dust, nearly unscathed.

Is that black ring on the back end the motor closure? Just looks differant.

Nothing special, standard AT after closure, and medusa nozzle for the 685.

 

[rfjustin]

M-1850 next time... Hopefully will result in straighter boost.

 

[BF Rockets]

Maybe I missed it if you mentioned it, but was is the source of the carbon fiber tube in this build? It's not the typical filament wound type, obviously.

 

[rfjustin]

Maybe I missed it if you mentioned it, but was is the source of the carbon fiber tube in this build? It's not the typical filament wound type, obviously.

Wildman Rocketry

 

[Faroutspacenut]

M-1850 next time... Hopefully will result in straighter boost.

Nice flight! Any idea what caused the dip/wobble off the rail?

 

[rfjustin]

Nice flight! Any idea what caused the dip/wobble off the rail?

IMHO, it happens with small/light rockets with moon-burner cores/motors.

Another example in similar size/weight 75mm minimum diameter rocket:

 

[ether]

how did the flyaway rail fair after the launch?

 

[rfjustin]

how did the flyaway rail fair after the launch?

Perfect, no issues/concerns to speak of.

 

[BryRocket]

@rfjustin Couple of questions, what epoxy did you use for the carbon rocket filets. I’m unfamiliar with that color. Also, did you fly that as a 2 stage yet?

 

[rfjustin]

@rfjustin Couple of questions, what epoxy did you use for the carbon rocket filets. I’m unfamiliar with that color. Also, did you fly that as a 2 stage yet?

JB Weld.... and no, 2 stage got pushed to Airfest this year 2021.

 

[BryRocket]

JB Weld.... and no, 2 stage got pushed to Airfest this year 2021.

How is it working with the JB? Any other recommendations? I’ve been using Proline, which I like, but it can be a bit finicky. Like really runny early but then sets up quickly. I can manage with it but curious about other high temp options.

Thanks for the update re Airfest.

 

[rfjustin]

How is it working with the JB? Any other recommendations? I’ve been using Proline, which I like, but it can be a bit finicky. Like really runny early but then sets up quickly. I can manage with it but curious about other high temp options.

Thanks for the update re Airfest.

With JB, there can be a bit of a learning curve, practice on something else (not the real deal first).

Tape everything that you DONT want JB on get some throw away epoxy of plumbing flux brushes. The ones pictured I get from Menards for like 90 cents for (3).


Use the flux brush to "wet out" the fillet area, then start pooling JB small section at a time.

 

[rfjustin]

Then you end up with this, basically nightmare fuel...

 

[rfjustin]

Form your fillets with your round tool of choice, pull tape quickly, then clean up what little is left at the front and rear of the fillet.

 

[BryRocket]

Thanks! I’ll give it a try on something.

 

[Conway Stevens]

Justin, Do you always use the Jb on your minimum diameter stuff? Anything else you like to use?

 

[rfjustin]

Justin, Do you always use the Jb on your minimum diameter stuff? Anything else you like to use?

I've used Loctite Hysol E 120-HP, but has not been flight tested (by me) quite yet....

https://www.rocketryforum.com/threa...se-cone-and-4-fins.162266/page-6#post-2078112

 

[Conway Stevens]

I've got a couple of different min diameter projects going including a Mach3 from wildman hadn't decided on an expoxy yet. Thank you!

 

[Rocketman_dan]

@rfjustin Thanks for the post about the jb weld fillets it helped me a lot. I just got done with the fillets on my wildman mach 2 and I still want some more durability with tip to tip. I found a few tutorials on the subject and it doesn't seem too difficult, however, I see that the method you use looks to have good results. I have a few questions though:
1. What weight fiberglass would you recommend for the mach 2? I was thinking something like 2 oz.
2. Do you add a breather cloth and release film on top of the peel ply with weight or do you just use peel ply alone.
3. I was thinking of using fibre glast 2000 epoxy as recommended in a sport rocketry magazine as it has a room temp cure and has a higher temp tolerance than west systems. Is this a good option as I will be using either a k480 or k375 or both so idk if the motor cases will get hot enough for the 2000 epoxy to get soft or even melty. I do not have a curing oven so I don't think I could use aeropoxy.

Thanks for this thread I learned a lot from it!

 

[Conway Stevens]

@rfjustin Thanks for the post about the jb weld fillets it helped me a lot. I just got done with the fillets on my wildman mach 2 and I still want some more durability with tip to tip. I found a few tutorials on the subject and it doesn't seem too difficult, however, I see that the method you use looks to have good results. I have a few questions though:
1. What weight fiberglass would you recommend for the mach 2? I was thinking something like 2 oz.
2. Do you add a breather cloth and release film on top of the peel ply with weight or do you just use peel ply alone.
3. I was thinking of using fibre glast 2000 epoxy as recommended in a sport rocketry magazine as it has a room temp cure and has a higher temp tolerance than west systems. Is this a good option as I will be using either a k480 or k375 or both so idk if the motor cases will get hot enough for the 2000 epoxy to get soft or even melty. I do not have a curing oven so I don't think I could use aeropoxy.

Thanks for this thread I learned a lot from it!

The wont create enough heat to be an issue. Motor exterior temps have to be certified 200f or less. Let alone the heat difference between the fins and the body will drop significantly. In extreme supersonic flights you can get alot of heat increase across the fins as air flows around. This would potentially be a higher heat issue then heat from the motor. You look to be using slower burning motors so you may not end up that fast.

 

[Rocketman_dan]

The wont create enough heat to be an issue. Motor exterior temps have to be certified 200f or less. Let alone the heat difference between the fins and the body will drop significantly. In extreme supersonic flights you can get alot of heat increase across the fins as air flows around. This would potentially be a higher heat issue then heat from the motor. You look to be using slower burning motors so you may not end up that fast.

Ya I just read a thread on that and it does seem that the temp of it going supersonic could be a tiny bit greater than the motor case temp. I think that the fibre glast 2000 epoxy resin will be fine but I am now just deciding on if I should go with 4oz or 2oz. Also do I have to put a weight of some sorts on the layup while it is curing or can I just leave it with peel ply?

 

[Conway Stevens]

4oz is what I use in 3 layers staggered lengths just past the fillets, 1/2 way up the fins, 3/4 to full length across the fins. I do not use peel ply as ive understood the potential for microfractures in the epoxy can occur.

 

[Rocketman_dan]

4oz is what I use in 3 layers staggered lengths just past the fillets, 1/2 way up the fins, 3/4 to full length across the fins. I do not use peel ply as ive understood the potential for microfractures in the epoxy can occur.

Ok I was thinking that even for a 54 min. dia. rocket 2oz is a little thin. So do you just wet out the airframe and fins, lay the glass on, brush the epoxy in, and call it good? If the finish is decent I will probably go with that.

 

[Conway Stevens]

I use the same method Tony does. Id use 4oz.
I wet out the cloth then lay it on. Minus the tape . Justin may use a different method. This being his thread.