Project Hurricane is a go. L2 Re-Attempt. Mac Performance Firestick XL. 100% Composite Materials. (Build Thread)

[Orien]

Turn. Up. To. Eleven.

Most people only go up to ten.

 

[Sandy H.]

Most people only go up to ten.

 

[Orien]

I've seen this at least 500 times and it never fails to crack me up. Dude is so earnest, yet so stupid.

Back to the build in next post. I promise.

 

[Orien]

Sanding sucks, "filler primer" doesn't fill s**t, spot putty stinks - both figuratively and literally, and I hate my life right now. That is all.

 

[Neutronium95]

I'm definitely thinking J motor for cert/maiden flight. The plan is to get a 5-grain CTI case and two spacers. I have a new found respect for the forces involved with full K motors now after this disaster.

Are you going to let a little shred hold you back? Get yourself an L1000 for the cert flight.

 

[Orien]

Are you going to let a little shred hold you back? Get yourself an L1000 for the cert flight.

Please subscribe me to your newsletter, sir.

 

[Banzai88]

Sanding sucks, "filler primer" doesn't fill s**t, spot putty stinks - both figuratively and literally, and I hate my life right now. That is all.

You were warned in post 3

 

[Orien]

I got tired of doing this...


...so I went to my corner hardware store (I love these places WAY more than the big box behemoths) to look for something that would make for good charge cups. Found these:


A little drilling and screwing and I think it should work fine. I arranged them so that there is room for the terminal blocks (not here yet). Am I missing anything?

 

[Orien]

You were warned in post 3

Well, you were right. I used almost a whole can just on the nosecone.

 

[Orien]

Sand and fill and primer and sand and fill and primer and sand and fill and primer...

I'm obviously getting something wrong here. Any suggestions?

 

[tsmith1315]

I'd use glazing putty to fill those pits. Use a Bondo spreader to apply it in very thin layers, a credit card or such will work. The tool should force it into the pits.

Put on a very thin layer, it'll dry very quickly. Then sand it with 320, taking most all of the glazing putty off, only leaving what's in the pits. Use a sanding block on the flat surfaces. I'd use my finger to do the fillets unless you have something that fits the fillet shape very well. Repeat until there's nothing much but sanding marks left to fill. Then use your primer to fill that.

Anything that takes more than a couple coats of primer to fill needs more than primer to fill it, IMHO.

 

[SkyFire]

This is a good video on flllets;
I use Hysol 9462 for the fillets so I can do them all at once (thixotropic epoxy).
Bondo Glazing and Spot Putty dries really fast. Sometimes I put it in a cup and thin it by adding a small amount of lacquer thinner. Works well for filling the small holes.

 

[Orien]

I'd use glazing putty to fill those pits. Use a Bondo spreader to apply it in very thin layers, a credit card or such will work. The tool should force it into the pits.

Put on a very thin layer, it'll dry very quickly. Then sand it with 320, taking most all of the glazing putty off, only leaving what's in the pits. Use a sanding block on the flat surfaces. I'd use my finger to do the fillets unless you have something that fits the fillet shape very well. Repeat until there's nothing much but sanding marks left to fill. Then use your primer to fill that.

Anything that takes more than a couple coats of primer to fill needs more than primer to fill it, IMHO.

The airframe and fin surfaces are no problem. It's the transitions where the fillets are. I'm just done with it. I just did another fill/sand/primer session. Moving on before I get any more demoralized.

 

[tsmith1315]

I'm just done with it. I just did another fill/sand/primer session.

Absolutely, keep going and don't sweat it!

 

[Orien]

I wanted to see some paint on her. Did a little night session.




Here we go again.

 

[Orien]

Getting all this sorted out looks daunting, but it’s really just two simple linear set-ups.

 

[Orien]

I mounted the terminal blocks (had to get a little creative with the forward end so the wing nuts cleared) and wired them up. Things are tight, but accessible.

 

[Chris_H]

Sand and fill and primer and sand and fill and primer and sand and fill and primer...

I'm obviously getting something wrong here. Any suggestions?

At every stage, it is important to understand what 'fully sanded' and 'dead flat' mean. You missed at the 'rough sanding the fillets' stage. A filler primer is not going to fill voids like that.

 

[Orien]

At every stage, it is important to understand what 'fully sanded' and 'dead flat' mean. You missed at the 'rough sanding the fillets' stage. A filler primer is not going to fill voids like that.

Good to know thanks. I really didn’t sand those fillets much. I thought I could just feather them in with the filler.

 

[Chris_H]

Good to know thanks. I really didn’t sand those fillets much. I thought I could just feather them in with the filler.

I like to get things as 'flat' as possible, as soon as possible. It makes the rest of the process so much easier, IMO. Polished finishes are quite tricky, and come with a steep learning curve.

 

[Orien]

Fuggedaboutit


She's got a whole can of 2K clear coat on her. Just needs a little polishing.

 

[Chris_H]

Yep. That is what the common folk do.

 

[Orien]

After a quick hand polish with some cutting compound:

 

[3stoogesrocketry]

Maybe I missed it , but how are you going to be launching this rocket ? I do not see rail buttons or lugs on it . Also you should start drilling your vent holes / attachment points before you paint your rocket.

 

[Orien]

Maybe I missed it , but how are you going to be launching this rocket ? I do not see rail buttons or lugs on it . Also you should start drilling your vent holes / attachment points before you paint your rocket.

Rail buttons are installed, vent holes drilled. But they don't make for the best photos when showing off the paint job.

 

[3stoogesrocketry]

Rail buttons are installed, vent holes drilled. But they don't make for the best photos when showing off the paint job.

Perfect . I was worried that step was missed during construction.

 

[Orien]

Last one, I promise.

 

[Orien]

 

[Orien]

Final form achieved.

Three 11/64” vent holes in booster compartment.
Three 5/32” vent holes in switch band (as recommended by Missileworks).
Two 11/64” vent holes in forward compartment.
Four shear pin holes each at nosecone and airframe break.

Fully loaded, no motor: 120 oz (7.5 lbs.)

 

[Orien]

I got the weights and CG right in Open Rocket, so the sims should be pretty accurate. Our club's launch site coordinates and a 15 mph wind were factored in.
Considering the CTI J355 Redline or the CTI J295 Classic. Red would look awesome, but that 4+ second burn on the 295 would make for some nice onboard video.