Scratch Building a Mega Red Max

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cjp

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I started my Mega Max yesterday,I received a gift certificate to LOC from my daughter and son-in-law for fathers day.I used it to get a 3.9 nose cone and slotted 27" tube.I'm right where I want to be with the height.I made my centering rings(3) out of 1/4" plywood with my wheel and circle cutter on my drillpress.Next I'll go to the hardware store and pick up a u-bolt and use the t-nuts I have on the top centering ring and aft ring for motor retention.I still have to get some 1/8" birch plywood for my fins.I'll get to try out my new Skil bandsaw that I got for Christmas.I'm off from work this coming week,I hope to get most of it built while I'm off.I'll post pictures as I go,Jim(Qquake2r)if your out there,I hope to use your ideas for this build.Your a great inspiration to me and a very good friend.Hope I do you proud.:wink:Mega Red Max Scratch Build 002.jpgMega Red Max Scratch Build 001.jpg
 
Hey Carl, this should be good! I've always loved the Red Max, and have considered upscaling it several times. Yes, you need to get that bandsaw unboxed and start using it. Once you do, you'll wonder what took you so long! I'd be lost without my bandsaw.

Is there a Michael's near you? Have you tried looking there for plywood? That's where I get most of my plywood. They carry 1/8", 1/4", 3/8", and 1/2". Be sure to go to their website and get a 40% off coupon.

https://weeklyad.michaels.com/coupons/

Are you going with 1/8" fins to save weight? I think it would look better with 1/4" fins, but they'd be heavier, and you might need nose weight with them. Do you have an Open Rocket file for your Mega Max?
 
Oh, and those centering rings look great! I've always wondered if you could simultaneously cut the OD and ID with one of those circle cutters.
 
The Estes kit uses 1/8" ply, over which balsa is laminated to achieve thick fins without weight penalty. I used 1/4" ply on my 38mm powered version, and they always looked a bit thin, though they held up without a problem. My question is what're you going to do for the nosecone?


Later!

--Coop
 
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I hadn't thought about sandwiching the fins with balsa. That's not a bad idea.
 
The Estes kit uses 1/8" ply, over which balsa is laminated to achieve thick fins without weight penalty. I used 1/4" ply on my 38mm powered version, and they always looked a bit thin, though they held up without a problem. My question is what're you going to do for the nosecone?


Later!

--Coop
I'm using a LOC nose cone,it may not be the exact size or shape but it's 5oz and with the 27" body tube come out at 40".I hope that answers your question.As for Jim's question on Michaels,yes that's the first place I went and it was sad as all the wood was warped.
 
Just for fun, I did a quick Open Rocket file. It's stable with 1/4" plywood fins and a G80.

My computer will not let me open your file,do you have the nose cone at 5oz.?As I stand now with the 3 centering rings,NC,bodytube at 19.5oz.Don't know what the added weight of the fins would be.I thought the 1/4" Birch plywood at Michaels was straight but the weight might be a problem.38mm is out of the question as I can't afford the Level1 certification or yearly NAR fees.A "G" motor is my limit.
 
Just for fun, I did a quick Open Rocket file. It's stable with 1/4" plywood fins and a G80.
With all the overbuilding I did with mine (40oz), it looks like the smallest mine will safely leave the pad on is a G80.
 
I did some more playing around in Open Rocket. With 1/8" plywood fins and centering rings, the weight is down to 24oz. It sims at 1300ft on a G64. I think it's doable.

View attachment Mega Max.ork

screenshot1.jpg

screenshot2.jpg
 
I did some more playing around in Open Rocket. With 1/8" plywood fins and centering rings, the weight is down to 24oz. It sims at 1300ft on a G64. I think it's doable.

The body tube(9.6oz) and nose cone(6.9oz), (3)1/4" centering rings(2.8oz) for a total of 19.3oz.The Nose cone on the LOC web store says it's 5oz.,so it's heavier than listed.I don't have the Birch Plywood 1/8" stock on hand to weigh,so don't know what it will add.I think based on how the stock kit is built,the balsa laminated my be the best choice.
 
I really like the idea of laminating balsa over the plywood. Now if you could just find some straight plywood!
 
Well had some progress on my build,cut out my fins,first with my jigsaw,and then finished up on my bandsaw.I added a 1/4" stainless eyebolt,will slice a third centering ring and add those to the CR to help me with my rail buttons.I cut a slice from a coupler and will add that to the aft end of the rocket after the CR.I did laminate one fin with 1/16" balsa to each side of the 1/8" birch plywood.Mega Red Max Scratch Build 015.jpgMega Red Max Scratch Build 003-001.jpgMega Red Max Scratch Build 004.jpgMega Red Max Scratch Build 007.jpgMega Red Max Scratch Build 011.jpgMega Red Max Scratch Build 016.jpg
 
It's looking great, Carl! I'm glad you're finally using that bandsaw! I really like the idea of laminating the fins with 1/16" balsa.
 
Thanks Jim,your idea of using a blade for metal in my jigsaw really helped make clean cuts.Thanks my friend.
 
The finer the teeth, the finer the cut. Cutting 1/8" or 1/4" plywood with a metal blade in a jigsaw is easy. Thicker wood, though, might burn and dull the blade.
 
Nice project my man.....I love it !!

I bought the mega kit and it`s one of my new favorites ,just a great ,stable flier and does not spin at all on the way up.

I overbuilt mine (as usual) you know ,epoxy ,Kevlar ,a real shockcord and 36" X form chute and red and black rail buttons.

So far it`s flown on CTI G57s and G68s ,which are perfect on our smaller field.

I too plan on doing a scratch build ,going to stretch it and give it canard fins and tweek the aft fins a bit ,I want that Sidewinder look :)

Nice thread ,should be fun to watch !!

Cheers


Paul T
 
Thank you for the kind words.I'm only using epoxy on the eyehook and t-nut.The rest of the build I'm using Titebond II.The centering rings are 1/4" birch plywood,they to are over kill.I made three but will only use two and cut up the third for rail buttons blocks.This gives me 1/2" wood to drill holes for the buttons.I should be able to hit that!LOL.
 
The first rail buttons I ever used were on my LOC-IV. I didn't know about the block trick then. I hit one centering ring, but missed the other. Rail buttons were very frustrating for me until I heard about the block trick here on the forum. Now they're easy-peasy. I love this forum!
 
Have the Rail Button blocks glued on,and have one fin with Elmers Wood Filler on it.The other two are laminated and are flat with weight on them drying until tomorrow.After I get the other fin finished with Wood filler,I'll install the motor mount and fins.More in a couple days.
 
Have the Rail Button blocks glued on,and have one fin with Elmers Wood Filler on it.The other two are laminated and are flat with weight on them drying until tomorrow.After I get the other fin finished with Wood filler,I'll install the motor mount and fins.More in a couple days.

You're using wood filler to fill the grain in the balsa?
 
You're using wood filler to fill the grain in the balsa?
I wanted something to harden the balsa and sand smooth.The 1/16" is very soft,mybe there's a better choice.I put a lite coat of white glue on my Semroc Magnum Hornet's nose cone,sanded it and primered.When I painted it,it pitted the balsa.I almost did the same with my first Mega Max fin,that's when I thought Wood Filler would be a better choice for a smooth finish.I thought about CA glue,it would take a couple bottles to coat those large fins.
 
I wanted something to harden the balsa and sand smooth.The 1/16" is very soft,mybe there's a better choice.I put a lite coat of white glue on my Semroc Magnum Hornet's nose cone,sanded it and primered.When I painted it,it pitted the balsa.I almost did the same with my first Mega Max fin,that's when I thought Wood Filler would be a better choice for a smooth finish.I thought about CA glue,it would take a couple bottles to coat those large fins.

The filler is probably a better choice than white glue. It should be much more sandable.
 
More updates today,have the fins sealed and sanded and the motor mount installed.It's time to glue the first fin to the motor tube.Using wood glue(TitebondII)for the fillets inside and on the outside of the fin.The shockcord attached to the eyehook has 1000# kevlar the first 24" stopping short of the top of the tube and then 14' 550# paracord.It was the last remains on orange spool and I had wanted around 15',so that worked out great and at 10ct a foot I thought was a great deal.More updates as they happen.Mega Max build 001.jpgMega Max build 002.jpg
 
Your internal fillets sure turned out better than mine do!

Well,I have not done them yet,LOL,let's see after I'm done Jim.I did get all the fins on and thought I'd put my regular size Max next ti the fin can.It's a biggin!Mega Max build 004-002.jpg
 
Thanks Jim,I can't come close to yours but I'm happy with the results so far.I don't have a clue how I'm going to paint this.I always put some dowel rod in the engine tube and slide that into a wine bottle to hold the rocket up.I might need a wine barrel for this one!!!
 
I made some painting stands for bigger rockets. They've worked out very well. The clamp is to keep the stand from tipping from the weight of the rocket.

stands1.jpg

stands2.jpg

216_sanding_sealer.jpg

147_primer.jpg

256_primer.jpg
 
Thanks Jim,I'm going to have to make something like that up.Great idea my friend,do you have any problems with the body tube turning when the wind blows while your painting?I have not tried painting with the tube laying on it's side.Mine are always upright.
 
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