Mega Red Max

I finished my Mega Der Red Max my wife and kids got me for Christmas. I have to say, its one on my favorite rockets and glad Estes came out with this mid power kit. It weighs in at 34oz without the chute and shock cord. An Aerotech G64 should send it up to 1000ft and a CTI G54 or G118 should send it to 1400 ft. I'll try it on a smaller H also.

I used west system epoxy for the build so no wood glue, the balsa fin sheets were laminated to the plywood with epoxy and weighed down until cured to prevent warping. I then fiber glassed the fins using 1.5 oz fiber glass cloth and release fabric to give a smooth strong surface. the body tube spirals were filled with glazing and spot putty.The external and internal fillets are west system epoxy with 406 Colloidal Silica for thickening and added strength. I used a ½” piece of PVC pipe to pull the fillets which left them smooth with very little sanding. An eye bolt, washer and nut were used on the top centering ring that holds the Kevlar shock cord. I used rail buttons instead of lugs since this is a big mid power Max.

The finishing took some time but I was happy the way it turned out. This rocket has quite a bit of area and takes a fair amount of rattle can paint to cover. I filled the nose cone seams with green squadron putty then primed and sanded twice before finishing with Rustolium Painters touch 2x Gloss Black. The body was primed and sanded twice then painted with Rustolium Painters Touch 2x Gloss Apple Red. Decals were applied and then Cleared and sanded before the final coat of clear was applied.

Photo of fin with fibreglass cloth and release fabric still on


Finished Mega Der Red Max


Rail Buttons


Family reunion photo of my Red Max's


Ken

These are sooo cool! Must be excellent to show up on three different pads with the same rocket. You should line these up for a 'perspective' shot...a real optical illusion to the "Max"! Very Nicely done!

WOW! Beautiful work. This is in my build que, just finishing up my mini.

Very nice work!!! Did you wet sand the finish and spray a clear on it? Looks fantastic!

Very nice! I just finished my yesterday. I replaced the bt with Blue Tube of the airframe and motormount and gave it a special paint job and Stickershock livery befitting a comment that was made last September. Once the surprise has been broken at Red Glare, I'll post pics.

Nice job. Im in the process of building mine as well. just ordered some glass for the fins last night. I really like how you did the fillets, looks great. will have to try that on mine when I get that far. I have flown my Mini Max on several occasions. I also have the Der Red Max to build next. I’m planning on changing the single 18mm motor to 3 18mm motor.

You might want to recheck those altitude predictions. A G80 single use will only put the Mega Max up 500 feet.

You've only added weight and you're more than doubling the projected altitude? Tell me your secret please!

Paul: the predictions seem to be in-line with sims. Our latest was heavily-built at 1111g, and sims are predicting 1,260 -ish on a the G-118. We went with rail buttons to get good liftoff speed: I feared with lugs and a 4' rod, it'd be too slow on lower-thrust motors. I'm guessing ours will find lower-mid H's quite palatable.


Later!

--Coop

Thanks guys for the comments, really appreciate it.

fyrwrxz, that's a cool idea to place all three on separate launch pads and fire them off the same time, hmmm I might just try that this spring, thanks.

Afterburner, After painting the red I did not sand it, I just put on the waterslide decals then cleared, after the clear cured I wet sanded with 600 wet/dry and then cleared again. I wanted to get the raised waterslide decal edges level with the rest of the rocket. Just have to be careful not to go down to far or you'll go into the decal.

PhlAsh, the blue tube sounds like a nice idea on this size of rocket, but give us a hint or part of the rocket picture to show us, since Red Glare is still almost a month away :smile: or send me a PM I promise i wont tell.

Paul, I went back to double check my file and I still come up with 1000 ft. Here is my .ork file, maybe I overlooked something.
View attachment Kens Mega Der Red Max.ork

Ken

I look forward to seeing this at Red Glare, if you're going. I'm the skinny guy with the two kids, 3 Maxes in Red, Blue and Pink, and the 4" Hornet.


Later!

--Coop

I've seen the same file.

However, I've also seen a completely stock Mega Der Red Max fly on a G64.....I think you are going to be pretty disappointed if you go to the field expecting 1000 feet. I'm not trying to rain on your parade or anything....I'm just saying this is a case of simulations not living up to real life.

BTW...try using 7 second delays instead of 10....

paul.nortness said:

I've seen the same file.

However, I've also seen a completely stock Mega Der Red Max fly on a G64.....I think you are going to be pretty disappointed if you go to the field expecting 1000 feet. I'm not trying to rain on your parade or anything....I'm just saying this is a case of simulations not living up to real life.

BTW...try using 7 second delays instead of 10....

Click to expand...

My apologies on the delay times in my file, I wanted to see what the max altitudes were for each motor and didn't set the proper delay yet.

I just took a look at the Aerotech Sumo, about the same size as the Mega Red Max. Maximum altitude with a G64 is about 1000 ft using a 4 second delay.
I think you might be right by the sim not being correct in that the Mega Red Max has more drag with the large fins, even though its the same height and diameter as the Sumo.

Thanks Paul :handshake:

Has anyone else flown there mega Red Max on a G64? would be interesting to know what altitudes it has gone to and delay times used.

I think a big reason the sim is off is it can't properly reconstruct the fins....with the plywood core and the balsa laminate. And like you said, there is a large amount of drag with those thick fins.

Personally....I would love to get this monster a little higher in the air. I nearly balked on picking one up just because of the low altitude...I got into MPR cause I wanted to go higher...but it's just such a cool addition to the fleet I couldn't resist. I recently upscaled the regular Max to 2.6 so I could add a 24mm RMS to the Max family as well

I did some searching on the web and found this page that might show a bit more accuracy on altitude with a good choice of motors and delay times for this rocket. The altitudes in the chart are lower than what Open Rocket tells us but from what you mentioned Paul this chart might be close to what your getting.
Let me know what you think
https://www.thrustcurve.org/motorguide.jsp?rocket=2617

Ken

I've been trying to figure out how to get open rocket to simulate the Mega Red Max close to real time altitudes with given motors. I posted a question here ( mega der red max pic ) asking if some one had some altimeter readings.

I tried adding weight to the open rocket simulation, almost 12oz! to get some close to real altitudes that G-Dog posted using 3 different motors and at least 2 recordings of each, but on the lower impulse motors the added weight didn't calculate properly. So I tried an app for my iphone called Rocket Calculator which I saw Advertised here on TRF, and its close to what G-Dogs altitudes were using a Jolly Logic Altimeter Two and the ones posted on here (thrustcurve.org). Here are a few calculations from Rocket Calculator App.


Altitude Prediction
Cesaroni G106

Total Motor Mass: 6.60 (oz)
Propellant Mass: 2.86 (oz)
Rocket Mass Without Motor: 35.00 (oz)
Average Thrust: 100.93 (N)
Burn Time: 1.36 (s)
Drag Coefficient: 0.75
Frontal Area: 12.57 (in²)
Number of Motors: 1
--------------------
Motor Class: 85.8% G
Burnout Velocity: 93.19 (m/s)
Burnout Altitude: 222.64 (ft)
Peak Altitude: 901.35 (ft) G-Dogs recorded altitude 878, 833 (ft)
Coast Time: 5.79 (s)

-------------------------------------------------------------------------------------------------------
Altitude Prediction
Cesaroni G125

Total Motor Mass: 6.86 (oz)
Propellant Mass: 2.89 (oz)
Rocket Mass Without Motor: 35.00 (oz)
Average Thrust: 124.00 (N)
Burn Time: 1.29 (s)
Drag Coefficient: 0.75
Frontal Area: 12.57 (in²)
Number of Motors: 1
--------------------
Motor Class: 100.0% G
Burnout Velocity: 108.75 (m/s)
Burnout Altitude: 248.19 (ft)
Peak Altitude: 1047.81 (ft) G-Dogs recorded altitude 1034,917,965,979 (ft)
Coast Time: 6.16 (s)

--------------------------------------------------------------------------------------------------------
Altitude Prediction
Cesaroni G88

Total Motor Mass: 5.36 (oz)
Propellant Mass: 2.26 (oz)
Rocket Mass Without Motor: 35.00 (oz)
Average Thrust: 83.95 (N)
Burn Time: 1.00 (s)
Drag Coefficient: 0.75
Frontal Area: 12.57 (in²)
Number of Motors: 1
--------------------
Motor Class: 52.5% G
Burnout Velocity: 61.35 (m/s)
Burnout Altitude: 104.09 (ft)
Peak Altitude: 508.46 (ft) G-Dogs recorded altitude 505, 534 (ft)
Coast Time: 4.68 (s)

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Here are a few other samples that I used

Altitude Prediction
Aerotech G64

Total Motor Mass: 5.33 (oz)
Propellant Mass: 2.20 (oz)
Rocket Mass Without Motor: 35.00 (oz)
Average Thrust: 56.84 (N)
Burn Time: 2.09 (s)
Drag Coefficient: 0.75
Frontal Area: 12.57 (in²)
Number of Motors: 1
--------------------
Motor Class: 74.2% G
Burnout Velocity: 72.59 (m/s)
Burnout Altitude: 270.76 (ft)
Peak Altitude: 774.41 (ft)
Coast Time: 5.13 (s)

------------------------------------------------------------------------------------------------------
Altitude Prediction
Aerotech G80

Total Motor Mass: 4.52 (oz)
Propellant Mass: 2.20 (oz)
Rocket Mass Without Motor: 35.00 (oz)
Average Thrust: 77.60 (N)
Burn Time: 1.70 (s)
Drag Coefficient: 0.75
Frontal Area: 12.57 (in²)
Number of Motors: 1
--------------------
Motor Class: 82.4% G
Burnout Velocity: 87.77 (m/s)
Burnout Altitude: 266.37 (ft)
Peak Altitude: 891.14 (ft)
Coast Time: 5.58 (s)

For me these seem to be close enough to figure out what I can expect for altitudes on a given motor I choose.
Just wanted to post this if it can help anyone else.

Ken

Managed to get some video of today's launch. 2 flights, one on a G64-5W and the second on a CTI G106-7 Skidmark. Both flights and recoveries were successful. I didn't like the cuffing of the Aerotech G-64W but once it got going it flew great.

[video=youtube;0mq0Ofp7ftc]https://www.youtube.com/watch?v=0mq0Ofp7ftc&feature=youtu.be[/video]

Another video of the flight that someone else took.

[video=youtube;wynZ3uEiftk]https://www.youtube.com/watch?feature=player_embedded&v=wynZ3uEiftk[/video]

Nice videos Ken, and very nice work on the rocket... I have one that is in my winter build pile....
will start after I finish a couple paint jobs and maybe even get to fly a few this fall.
TimE

Nice flights Ken, so far mine has flown on an Estes G80, and 2x on a CTI G80SK, this coming weekend its going on a CTI G125RL built a little on the heavy side should give it a nice ride to about 1100ft. I'll attach my Altimter2 and post the results.

Thanks guys for the kind reply's.
Tim, I think you will enjoy the build and flying it is just as much fun. It loves G motors.
Dave, please post some pictures or a video clip if you manage to get one. I have a G125RL sitting here also itching to hitch a ride in Max, I hope to use in a couple weekends.

Nice work Ken, and great flights, especially the G106. It'll easily handle an H, and even a small I, if you have the field for it.

qquake2k said:

I love that Skidmark roar!

Click to expand...

Jim, my same thoughts on skidmark's. My wife's parents are visiting from the east coast and never seen a model rocket fly, so I left the G106 as a finale. They loved it but my father in law was a bit nervous and asked if he should move back behind me a ways :lol:

dpower said:

Nice work Ken, and great flights, especially the G106. It'll easily handle an H, and even a small I, if you have the field for it.

Click to expand...

Thanks Paul for the kind words. Yes I agree that this Max is ready to move up a notch. Looking at what I have, an H180 Skidmark or an H200 Blue streak should work. I'll need to decide which one in 2 weeks at "Fall Fire" high power rocket event.

I'll be loading an I180SK (38mm) in my Patriot possibly this weekend, if not definitely at Red Glare next month, Cant wait to hear that one!

As a comparison, here are a couple still photos of My Max on the G106 Skidmark next to a couple photos from a K???? skidmark that one of the guys launched from this past winters Fire and Ice event. Any skidmark is a WOW, but that K was insane. I'm sure it woke anything hibernating from miles around, luckily no bears in the area :wink:

Jim, if my father-in-law would have seen that K skidmark I'm not sure I would let him in my car without a change of cloths:lol:.

Paul, your I180SK will be impressive! Let us know how it went and make sure you get some photos or video if your able.