L3 Build Intimidator 4

Well time to start my build thread.

UPS Finally delivered it and boy was that box ****ed up when i got it. Way to go guys, you are the best.....not.

So anyways, here we go...

Bathtub....most parts took some out already.


Building the Motor Mount...




Attached Retainer, using Aeropack tailcone retainer, yes i measured it all out already. Used JB Weld and had to hammer it on to get it to fit, defiantly not coming off.


Will install it tonight and add my first fins.

Using an M1350W, see my other thread about that one for details on it.

Subscribed!!!

I run the Rocksim file for the WildMan Intimidator 4 in OpenRocket and was shock to see less then 4000 ft on an AMW 1350WW motor. Did I get something wrong? My 10lb 4" L2 rocket will top 6000 ft on a K motor. This is the same diameter and should be a few lbs lighter.

What altitude are you expecting on this? I would guess about +15K. That would certainly be a very cool L3 cert flight.

It may have set it to 0 for the delay time, need to manually change it to "None". Its showing 16k+ form an AMW 1350. I am using the new Aerotech M1350 Single-Use.

Yes it will be to around 15k and Mach 1.25. Will be fun.

Aerow said:

It may have set it to 0 for the delay time, need to manually change it to "None". Its showing 16k+ form an AMW 1350. I am using the new Aerotech M1350 Single-Use.

Yes it will be to around 15k and Mach 1.25. Will be fun.

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This would tell me the builder hasn't done his L3 TAP/L3CC paperwork yet. It used to be that you couldn't start builiding without a L3CC member or TAP member OK.

The builder actually should have the skill to guess at the altitude without OR or RS. That's a skill that almost any RSO (only a L2 needed) does have..

Why would you bother to try and guess altitudes? Rocket simulators are important tools. I don't try and guess other measurements.


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It has been approved by my L3CC, and i have already done my package. He has already approved it and I am starting the build.

I have done the Sims for it, will be right around 15,400 and Mach 1.25. I don't have a true weight for it yet, but that will be in the ball park.

Yes we can do guesstimates for altitude, but I trust the sims more then my faulty math. <<<coming from an Industrial Engineer>>>>> I really do hate math.

DizWolf said:

My 3" l2 is 11 pounds and hits 7k on Ks

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Yes but were you able to guess it before hand?

With a weight of 378 oz, rocksim gives me 12,766' and 872 MPH.

Thats with an unadjusted cd, and the stock file's weight.


Good luck on the flight, and it looks like you have everything under control... don't let jerks get you down.

grouch said:

Yes but were you able to guess it before hand?

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guess? hell no. Why guess when we have computers that do it much better?

Ok so using OpenRocket it gives 374 oz.

With the new Aerotech M1350W it is showing 15188 and 952 mph.

And I agree, why do math when we have programs that can be used on a laptop to get more accurate estimates.

Hal8472 said:

Why would you bother to try and guess altitudes? Rocket simulators are important tools. I don't try and guess other measurements.


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As an RSO (or in some clubs, the LSO), when you are handed a rocket and a flight card, you must be able to guess the altitude (one with an OR or RS page could be way wrong, and you need to catch it) That "waiver" thing. By the time you're going for L3, you should be pretty good at a guess holding the rocket and a flight card. That's mid level skills in HPR. It's NOT a badge, but a journey.... Don't miss the journey to get a badge!

DizWolf said:

guess? hell no. Why guess when we have computers that do it much better?

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Because, with RS or OP, it could be garbage in-garbage out. An experienced HPR flier can tell you if you are wrong, without a computer. Until you have that skill, you shouldn't be looking for a new "badge" but instead, going on with the journey!

Ok , this is a good group of people for the most part . Reco I have seen most of your posts . Negative for the most part . There is some guys that don't use SIM programs. Both of my taps don't use them much . But I scratch build and use them a lot . Most of the time a weight on the pad will change . Placement of a harness will change . Your way is your way . I can post a SIM and everyone on this thread can use that SIM and they all will be different . I have seen posts for the guys on this thread . And know it will work . You I have seen post comments and nothing else . Not saying your a bad builder . It's to be happy with the good flights and help with not so good ones . That is the journey. I have gotten some negative comments on a build from a few , I was new and took a big chance on my L2 . I had a ace in the hole . It worked and a perfect flight . if you put down everyone in every post you will not get far . Yes you May be an L3 but there is a lot of ways to do something .

And on the L3 paperwork it asks about the flight and how you got to your calculations . You can do it with the math or with a SIM program . Have a laptop with all my Sims so can change out motors ,wind direction of the wind and rail length .

DizWolf said:

Something has to be screwed on your rocksim handeman. My 3" l2 is 11 pounds and hits 7k on Ks

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Nothing to do with Open Rocket ( I don't have RockSim). That is actual flight data. Aerotech 54/1704 loads (K695R & K550W) put the 10.5 lb (minus motor) 4" rocket about 6,500 ft. A similar weight but only 3" should be about 7K ft. I don't see the discrepancy.

That is very close to my Dark Star Extreme flight on an M 2240.
It did 13,091 ft according to SL-100
If I remember correctly; it weighed in around 26 lbs loaded.

also see this thread for other related info:
https://www.rocketryforum.com/showthread.php?67520-SL-100-Velocity-accuracy

Once you get up around Mach you CD increases

JD

DizWolf said:

With a weight of 378 oz, rocksim gives me 12,766' and 872 MPH.

Thats with an unadjusted cd, and the stock file's weight.


Good luck on the flight, and it looks like you have everything under control... don't let jerks get you down.

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Handeman said:

Nothing to do with Open Rocket ( I don't have RockSim). That is actual flight data. Aerotech 54/1704 loads (K695R & K550W) put the 10.5 lb (minus motor) 4" rocket about 6,500 ft. A similar weight but only 3" should be about 7K ft. I don't see the discrepancy.

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I was agreeing with you.... not questioning your flight data. The intimidator 4 on an M1350 should go well above 4K

chris m said:

And on the L3 paperwork it asks about the flight and how you got to your calculations . You can do it with the math or with a SIM program . Have a laptop with all my Sims so can change out motors ,wind direction of the wind and rail length .

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When I got my L3, you had to have the design approved before you built. This was a good thing, as sometimes people propose a design that won't work, and before a minutes is spent on construction, the candidate can be corrected.

While some people dispute my "an RSO should be able to take an (educated) guess given a flight card and a rocket, I did play around in RS a bit today, using a rocket I knew well.. Using the same .rkt file, I could change the "simulated flights" altitudes +/-30%, without a change to the design, materials, or specific motor. RS and OR are at best a guess. An experienced flier will KNOW, (within reason) given a rocket in one hand and a flight card in the other. Experience allows fliers to know when the have to adjust one the the RS/OR parameters. Inexperience means you trust exactly what RS/OR tells you, even if you got the wrong checkbox checked....

Not required in TRA. Just has to be approved before flight. Of course he's mentioned he's NAR and it was already approved, so what's your point?

At any rate, we should stop polluting his build thread with this discussion.

I just pruned the crap out of this thread. Keep it civil and on topic, guys. A lot of people like to use TRF build threads as part of their L3 documentation. As a TAP, I like this approach, and to that end, constructive criticism is absolutely encouraged. But I would NOT like to waste my time reading through a nasty off-topic argument. Please respect the OP and let him document his build.

Thank you.

--david
TRA 5590 TAP / Moderator
and other stuff I guess

Sorry for my posts....

DizWolf said:

Not required in TRA. Just has to be approved before flight. Of course he's mentioned he's NAR and it was already approved, so what's your point?

At any rate, we should stop polluting his build thread with this discussion.

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Doesn't the design include the motor and expected altitude?

Consider the case where you're planning for L3, and you have the rocket designed, and ordered/bought stuff for the motor. The waiver at your site is for 7500' AGL.

When would you want to know that your motor was a "waiver buster" but you didn't catch it for a bad setting in RS/OR? During initial talks with your TAP/L3CC person, or the day you want to fly it?

Sorry, work has been hell, um got MMT in place and secured in place with some Rocketpoxy.

Yes you can inject with the stuff, just need to be quick, like less than 10 min before it sets up too thick.

Forogt the picture, butI took the mmt adn put it in place, then used a syringe to put epoxy on the bottom of the middle centering ring, waited till it thickened then fliped it over and did the top of the bottom one. Then drilled a 1/4 inch hole and injected into the space between the top adn middle centering rings. Should create a nice bond. I did sand the entire area inside the body tube before inserting it.

Next I tacked in the fins with some more epoxy and lined them up. Drilled 3 holes on each side of the fins and injected Epoxy to form internal fillets along the mmt and fin. Tilted it back and forth to spread it around.



Started my external fillets as well, poured on last night and did one this morning at like 2am before i left for work. Will do the last one tonight. This is just some extra epoxy, I made them look better, but my camera died before i could take a final photo.


Started working on my Av-Bay, using an RRC3+ and RRC2+, both have been flown multiple times and are very reliable.

Bulkheads are aluminum which was fun to drill out, I recommend a vice if you have one, or you may come out missing parts of your body. <<<< Hit my leg, ouch.

And I built my Eggfinder Tx and Rx yesterday, both work great, dropped the Tx down the road and drove ~2 miles away and still had some packets coming in. So I feel pretty good about it, its usually pretty clear up in Northern CO, and if i launch right at the beginning of the day I shouldn't have to deal with wind, *Fingers Crossed*.

Will take more pictures tonight, I am going to TN for a buisness trip so not much work will be done over the next week. After the fin can all that will be left is to finish up the Av-bay, and nosecone bay for the tracker, and to attach the recovery system.

Going to be using a 24" Cert 3 Drogue and a Fruity Chutes 60" Iris Ultra.

I am off the week of the launch, so I will get it all completed in time.

Ignore my bad spelling, I am very tired atm.

Remember that either OR or Rocksim will likely give you a slightly optimistic altitude. Likely, it will be 5-10% lower.

I am working on my L3, which is a Wildman Extreme- similar in many respects. What parachute you planning on?


Mark Koelsch
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I'm going with a 60" Iris Ultra, should bring it down right around 20ft/sec. Open prarie so i don't need to worry about hard landings, just the wind if i launch too late in the day. But then the land is so open I will just be in for a long hike, no vehicles are allowed off the road.

One guy hiked like 6 miles the last time i was there, but it was pretty windy, If i launch right at 9AM when the range opens there shouldn't be hardly any wind if any.

I think you might find the drogue a little large, but that is just an opinion.

I am going with a 60" Skyangle, but if I did not already have it I might well have gone the same route you are.


Mark Koelsch
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I've been liking drogueless lately. Brings it down like a rock.

DizWolf said:

I've been liking drogueless lately. Brings it down like a rock.

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That is all I have done minus one flight. I am thinking of changing that though after a buddy got some really great pictures of one of my rockets getting tangled up while descending drogue less.




Mark Koelsch
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