My "first" high powered build (Binder Devistator) - advice needed

[zeotherm]

So, while I technically have my Lvl 1 certification, I did it with a well built large mid powered rocket (a Sirius Interrogator G). It flies great, but after a year away from the hobby (crappy life getting in the way) I want to step up to a "true" high powered rocket. I have a BinderDesign Devistator and it looks totally awesome, but I have a few questions and seek out advice from those who have gone before me

I am hoping to get this up and ready for a maiden flight at LDRS in a few months. For the beginning I am not going to do a dual deploy, just a simple single shot sans electronics. If all goes well in the beginning I think I might upgrade to dual deploy and go for my Lvl 2 cert later in the summer.

So my questions: where do you get/what do people like to use for fiber in epoxy to make a nice composite?

Second, Binder suggests in the instructions that for high speed flights, that I would want to reinforce the fins with carbon fiber or fiberglass. I have no idea how this is done and am hoping anyone can send me in the direction of a pointer or two.

Thanks for all the help. I'll post pics as I go along

 

[Steve Shannon]

Look at YouTube videos from tfish38, who also hangs out here as TFish. His name is Tony and he shows one of the best fin reinforcement methods there is with his tip to tip on a Kestrel rocket.

 

[MaxQ]

So, while I technically have my Lvl 1 certification, I did it with a well built large mid powered rocket (a Sirius Interrogator G). It flies great, but after a year away from the hobby (crappy life getting in the way) I want to step up to a "true" high powered rocket. I have a BinderDesign Devistator and it looks totally awesome, but I have a few questions and seek out advice from those who have gone before me
I am hoping to get this up and ready for a maiden flight at LDRS in a few months. For the beginning I am not going to do a dual deploy, just a simple single shot sans electronics. If all goes well in the beginning I think I might upgrade to dual deploy and go for my Lvl 2 cert later in the summer.
So my questions: where do you get/what do people like to use for fiber in epoxy to make a nice composite?
Second, Binder suggests in the instructions that for high speed flights, that I would want to reinforce the fins with carbon fiber or fiberglass. I have no idea how this is done and am hoping anyone can send me in the direction of a pointer or two.

Thanks for all the help. I'll post pics as I go along

There is probably a "how to" on tip to tip fin glassing on this forum, probably any number of build threads.
https://www.jcrocket.com/tttjig.shtml
tfish38 has a video on YouTube:
https://www.youtube.com/watch?v=PtYYsX3VEmc

I've used West Systems for fiber glassing, they have micro light filler that works well for fin filets.
The guys that use fiber can recommend something. Go to the fillers section here:
Their whole product line here:
https://www.westsystem.com/ss/the-105-system/

Carbon Fiber is nice stuff, but unless you are after weight reduction, fiberglass is cheaper.
I've been going over price lists of CF fabric at CST and Aerospace Composites.
Lots of choices out there.
Got a big roll of CF from Applied Vehicle Technology.
https://www.avtcomposites.com/products.php3
2X2 Twill Carbon Fiber
Came on rolls in the width I wanted, making layup on the larger airframe component easier.

I went looking for .005 thick mylar forCF layup, found that at Hobby Lobby.
Trade name is "Dura Lar" near the art and frame section.
The larger 36 "wide roll was only .003 thick so I had to settle for the smaller 20" wide roll.
CF will come out shiny smooth with a mylar over the layup while it cures.
You'll want to get a peel ply for a rough surface on a CF layup if you want to adhere something to it.

CST/The Composites Store : there are reasonable price rates available in 42 "wide rolls in 2.0 to 3.5 oz. and 5.7 oz. for minimum quantities (lengths).
LIGHT WEIGHT CARBON FIBER FABRIC, 3.5 oz./sq. yd., 42" wide 3.5 oz. Carbon Fiber Fabric - Plain Weave
24 X 24 Thread Count 0.007" Thick

https://www.cstsales.com/carbon_fabric.html

- Carbon Fiber 5.7oz 2x2 twill seems to be popular in other build threads.

Aerospace Composites: Prices look higher here for lower quantities of comparable CF cloth, although the hybrid aramid/CF cloth looks interesting and less expensive:

https://www.acpsales.com/Carbon-Fiber-Woven-Fabrics.html
https://www.acpsales.com/Carbon-Aramid-Fabric.html

5.4 oz Carbon/Aramid Yellow Fabric: 50" Wide 2x2 Twill
"This Carbon Fiber/Aramid hybrid offers the stiffness of carbon fiber and the impact resistance of Aramid all in one material. It is manufactured with 3K Carbon and KEVLAR® fibers and the 2x2 twill weave allow for easy layup on compound curves.
The Aramid fibers are dyed with red, blue or yellow dyes for eye-catching color."

 

[MikeyDSlagle]

Mike Fisher (owner/operator of Binder Design) is great to direct questions to and he will more than likely chime in here. If you aren't going with electronics, simple level 1 flights or what not...I would venture to say you will not be needing the extra reinforcement mentioned in the instructions. High speed to Mike is probably well over Mach, probably even Mach 2 When you want to upgrade to dual deploy or when you are ready for those high speed flights, you will probably want another rocket anyway. Build the Devastator per instructions and enjoy the simplicity of it. Built per instructions it can probably handle 'K' motors no sweat.

Several of us recently had a brief discussion about adding chopped fiberglass to fillets and whether or not it was worth it. I am part of the "it is worth it" crowd.

Here is the thread for that.

As mentioned in that thread, I bought some woven fiberglass from Wal-Mart and cut me some fibers from it. An easy way to cut it is get a rotary cutter, looks like a small pizza cutter. Wal-Mart probably has one in either fabrics or crafts, if not, Hobby Lobby does. It doesn't take much at all. Since then I have tried with laminating epoxy and had horrible results. Haven't gone back to evaluate the process or what I did wrong.

You'll get lots of answers and help here. It wouldn't hurt to shoot Mike an email as well. He will answer any questions you may have.

Mikey D

 

[4kids49]

Are you using 38 mm or 54 mm motors? There are some pretty powerful 54 mm motors. If you are using 38 mm motors, you may not need to glass the fins. It all depends on how high of speed you are looking at. As other people have said, Mike Fisher would be a great person to ask.

 

[BDB]

I'm a huge Binder fan. I've built the Tyrannosaur and Terrordactyl, both without glassing the fins. (Though I should mention that I'm glassing one now to repair a crack after a hard landing--100% my fault.) Mike uses super-high quality plywood for these fins. I doubt you need to reinforce them.

Post lots of pictures as you progress. The Devastator is on my short list.

 

[OverTheTop]

I have a Binder Design Velociraptor that flew quite a flights on L motors, typically to just under Mach 1. No problems with fins or fillets with the standard cardboard airframe and plywood fins (no additional fiberglass layers). As BDB mentions, the ply is great quality. The Binder Design kits usually get peoples' attention

Go for the 54mm motor mount. You can always adapt down.

My build thread is here, but most of the earlier pics have disappeared due to the image hosting site. It does show the rebuild I did with fiberglass airframe after it sat in a field for 11 months. Great regular flier on L motors.
https://forum.ausrocketry.com/viewtopic.php?f=6&t=1782

 

[Binder Design]

No need for glassing fins on motors up to L class. It's our standard instruction template that has to cover all the bases. And we've upgraded to the highest quality aircraft plywood since the instructions were written.

You can use wood glue for all paper/wood bonds, but the milled fiber/epoxy does make for nice fillets. With the fin stiffeners the kit comes with, extra fillet material only adds additional weight.

Just build it stock, no need to build a flying boat.

 

[Nytrunner]

No need for glassing fins on motors up to L class. It's our standard instruction template that has to cover all the bases. And we've upgraded to the highest quality aircraft plywood since the instructions were written.

You can use wood glue for all paper/wood bonds, but the milled fiber/epoxy does make for nice fillets. With the fin stiffeners the kit comes with, extra fillet material only adds additional weight.

Just build it stock, no need to build a flying boat.

From a future High-power kit buyer: You say they're suitable up to L motors, does that include loads like V-max, Warp-9, and Super Thunder? Or is the high thrust short enough to be survivable.

 

[Binder Design]

From a future High-power kit buyer: You say they're suitable up to L motors, does that include loads like V-max, Warp-9, and Super Thunder? Or is the high thrust short enough to be survivable.

They've flown on every commercial K that is currently manufactured.

 

[Nick@JET]

Forget the fiber filling epoxy and just buy Rocketpoxy. If your going to mix CF with your epoxy I like the longer fibers - just a pinch, mix thoroughly and it becomes like rebar for your epoxy.

I would agree with Mike himself - especially if your not going dual deploy then your not going to punch it out of site or you would just build DD from the start.

Certainly nothing wrong with wanting to learn a tip to tip technique though but the rocket will take what you can throw at it without doing or if you multi Mach buster, likely build another rocket specifically for that.

 

[zeotherm]

Thanks for all the advice so far everyone! It is really appreciated. I've worked on prepping the body tubes, filling and sanding and dry fitting things. I have a few more questions.

1.) I had a question about epoxy, but from this thread it seems that most recommend RocketPoxy. I was just wondering if BSi's 30 min epoxy would be okay to use for putting together the motor mount and the heat it would be exposed too?

2.) Does anyone have any recommendations as to a good 54mm to 38mm adapter for an engine? I don't have time to get stuff together for my Lvl 2 before LDRS where I want to fly this, so I am going to stick to an I motor for the first flight

3.) The directions say the MMT is built for Aerotech and Dr. Rocket cases. Can it also work with CTI engines/cases as well? I simply don't have any experience with Aerotech's stuff (not that it matters, since I don't have any 38 OR 54 mm cases, but I was just wondering).

Thanks all!

 

[BDB]

Are you using an Aeropack retainer? If so, use one of their adapters. If you're planning to use the Binder retainer, Mike can make a simple adapter for you for cheap.

You could use RocketPoxy for the whole build, but BSI 30 min, or even wood glue, will be fine for everything besides the filets.

I fly both CTI (54 and 38 mm) and Loki (38 mm) motors in my Tyrannosaur using the Binder retainer and adapter. You friction fit the 38 mm case in the adapter and the retainer holds the adapter. It's not as sexy as an Aeropack retainer, but It's a simple, cheap and effective system.

 

[chris m]

This is my input to this . as your title said your first high power build . if you plan to fly 38mm and the rocket can fly 54mm build it that way and you can adapt down . wish i did when i started

 

[OverTheTop]

I had a question about epoxy, but from this thread it seems that most recommend RocketPoxy. I was just wondering if BSi's 30 min epoxy would be okay to use for putting together the motor mount and the heat it would be exposed too?

I used JB weld for the motor mount tube and aluminium motor retainer, and West System 105/206 everywhere else. No problems have been seen with what I used. The cardboard tubes do a remarkable job of insulating the heat from the motor I think.

 

[Binder Design]

3.) The directions say the MMT is built for Aerotech and Dr. Rocket cases. Can it also work with CTI engines/cases as well?

Yes. We need to update the instructions. They were written before CTI came onto the scene. JB Weld on the retainer, wood glue or epoxy on all wood/paper bonds otherwise.

 

[zeotherm]

After a few nights of false starts, I got to finally get going in earnest on this rocket the other night. Not a whole lot of progress, filled and sanded the body tubes, and started on the assembly of the motor mount tube, but given how life has been the past two years it was great to be building again Here are some shots of the progress (as it is) so far.


Also, big thanks to Mike from Binder, and the folks at GiantLeap Rocketry for helping me procure the parts for 54-38mm adapter.

(I have no idea why those are rotated... >:| )

 

[mpitfield]

View attachment 312855

Also, big thanks to Mike from Binder

First off I want to acknowledge Mike Fisher from Binder as well. Mike and I had a minor miscommunication which he called me to discuss. Not only was he professional, but we worked through the miscommunication and he shipped out my part right away. He also took it one step further and cut the slots N/C...now that is a guy who goes above and beyond, and that is the epitome of excellent customer service.

Secondly re. the Devastator retainer in the pic. Before I assembled the retainer on my retro Devastator, I put a thin coat of JB Weld over the ply-ring. It gives a nice black colour to it, which I think looks great, and it should be easier to clean and provide a bit more thermal protection from the exhaust.

Nice build!

 

[BDB]

View attachment 312852View attachment 312853View attachment 312854View attachment 312855

This looks great, but can you explain what is going on with the motor mount, nozzle and retainer? I'm not quite seeing how this all is fitting together. (And I really want to know because, like I said in a previous post, this thing is on my wish list.)

 

[BDB]

And I used to have the sideways-picture-thing happen all the time. It's annoying but pretty easy to fix. Open the image file on your computer in whatever basic editor you have. Rotate it a couple times, and save it again in the correct orientation. For some unknown reason, the pic will then stay upright when you upload it to TRF.

 

[zeotherm]

This looks great, but can you explain what is going on with the motor mount, nozzle and retainer? I'm not quite seeing how this all is fitting together. (And I really want to know because, like I said in a previous post, this thing is on my wish list.)

The MMT in the 1st picture has the end cap that Binder shipped with it. There is a groove in it that allows a snap ring to be set in that will hold a 54 mm motor in place. There is also an aluminum bell nozzle that relay just sort of sits on top of that retainer as a decorative piece. In between the two is a wooden O-ring with a beveled outer edge so it can sit flat against both the motor retainer on the inside and the angled decorative nozzle on the outside.

The smaller MMT is just an adapter for fitting 38mm engines in the Devistator. It is a 38mm MMT with rings from Mike at Binder and a slimline retainer epoxied to one end. I'll post an "all together picture tonight"

 

[zeotherm]

Secondly re. the Devastator retainer in the pic. Before I assembled the retainer on my retro Devastator, I put a thin coat of JB Weld over the ply-ring. It gives a nice black colour to it, which I think looks great, and it should be easier to clean and provide a bit more thermal protection from the exhaust.

Nice build!

Did that last night, just didn't get a picture! And thanks!

 

[Binder Design]

First off I want to acknowledge Mike Fisher from Binder as well.

Thanks for the kind words! Looks like you're coming along nicely.

 

[Binder Design]

can you explain what is going on with the motor mount, nozzle and retainer?

Our nozzle is a three piece system. It consists of our motor collar retainer, (which is the same retainer on the Velociraptor) the aluminum nozzle shroud, and a plywood ring to center the retainer in the shroud. It's our way of providing a nice decorative bell nozzle without having to machine it from solid billet which would exceed the cost of the kit. Once it is all bonded together, it is quite strong.

 

[Binder Design]

like I said in a previous post, this thing is on my wish list.)

Just a heads up. We will be discontinuing this kit very soon. Our cost for the large amount of plywood it takes is a deal breaker. When we first released it, the fin stiffeners were made from double tempered masonite but people complained. So we bit the bullet.

I don't want to raise the price so without a major redesign, it is unprofitable to continue it.

 

[MikeyDSlagle]

Is there a new kit in the works to take it's place?

 

[Binder Design]

Is there a new kit in the works to take it's place?

We're kicking around a few ideas.

 

[MikeyDSlagle]

:headbang:

Finally got a shot of primer on my Tyrannosaur today. Well part of it anyway. Jackhammer on my short list. I'll be watching!

 

[zeotherm]

Okay, after life getting in the way, and a virus tearing through my house, I finally got some time this morning to do a bit more work! I had gotten the fins beveled a bit a few weeks ago, and they are shown here.



I then fitted the MMT in the body tube and marked it so I could apply a thin layer of Titebond II to the MMT to make good surface for the fins to bond too when I glue them in. (bringing my LPR techniques into the HPR realm, we'll see if this is a good idea later )



Some dry fitting showed that the slots for the fins were about 1/16 of a inch too short, so I opened them up and widened the slots a hair (maybe a few mils) to make for an easier fit. Now, I have everything ready to go to start securing things to the fincan and moving on!

 

[zeotherm]

Okay, I *think* Satan's cold has finally worked its way through my body and my family... And the "blizzard" has come and gone. Finally time to do some building!

Got the fins tacked on and the fin can out. Epoxied the front centering ring in place and added some small epoxy fillets to the fins near the centering rings since I skimped out and used TiteBond II to tack the fins to the MMT.

Here's what I've gotten so far:







A little sloppier than I'd like, but I had made quiet a mess by this point