L2 Binder Design Velociraptor Build

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fyrfytr310

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If you have seen this thread, then you know I have returned to the hobby after some years. Fortunately, my L1 certification was through NAR so I am G2G for moving on up. I will be spending this summer working on some relatively quick MP and L1 HP projects but the coup de grâce will be my Binder Design Velociraptor for L2.

I am going to take my time with this build as I would like it to become my best finished product ever. I want to try a small number of new things on this but overall, I am going for the uncomplicated design/mostly stock concept. My initial thought is to put it up on a K550 but I need to see where it sims to make sure the fields I have access to are feasible. I am on the fence with glassing and it is somewhat unnecessary with Binder kits but I might go ahead just for the experience (anyone using the Easy-Glas Sock from Giant Leap?).

Anyway, I ordered the rocket and altimeter (RRC2+) last night so this post is serving mostly as a placeholder until I can get to the unboxing. In the mean time, for those that have done this kit, or anyone wishing to opine regardless, feel free to send some advice along.
 
I am on the fence with glassing and it is somewhat unnecessary with Binder kits but I might go ahead just for the experience (anyone using the Easy-Glas Sock from Giant Leap?).

Congratulations on getting your Velociraptor. Build it whatever way makes you happy. One of the cool things about Binder (and LOC) kits, are that they don't need glassing. There are so many fiberglass and thin walled fiberglass kits out there. It is nice having a light rocket that you can put a small motor in and not think about much. Looks like the Velociraptor can handle a K550 with no problem. Anyway, good luck with your build.
 
. I am on the fence with glassing and it is somewhat unnecessary with Binder kits but I might go ahead just for the experience (anyone using the Easy-Glas Sock from Giant Leap?).

.

Yes I have on several rockets, before I went to fiberglass cloth, it's a good way to learn, but has it's own learning curve. I did it for the same reason....learn how to glass rocket. Be aware though, you will have a bit of a lip where NC meets tube due to "thickening tube OD "with the wrap of glassed sock or fiberglass for that matter.
Not hard to deal with...but be aware it will happen, just part of it.
Some type of re-enforcement is always a good thing for larger projects. Not really needed unless you are pushing it flying, but more so for preventing damage during travel & storage. Most of my rocket mishaps happen then.

I was glad I used it on my "Galaxy" from Binder... I really loved that rocket. Got my L-2 with it.
First the sock is not fiberglass, but some type of polyester fabric, yet it does a nice job of protecting /stiffening airframes. Be sure to stretch it snugly over the airframe and use ties on each end after pulling and twisting the ends to hold in place. This will prevent movement of fabric when brushing/rolling on the laminating epoxy.

Do NOT try to fill the weave with epoxy. Do that later with light weight filler. You only want enough resin to saturate the cloth and bond it to the tubes. Easy to tell, the cloth will be translucent when saturated correctly, white where dry or not enough resin.

I put CR's in each end of tube.....ran PVC or broom handles through them. Then stretched the sock over tube and pipe, used wire ties to hold to pipe. [Kinda like when you twist up the bread bag and wire tie it.] Hang the tube and pipe from saw horse's or similar to ease working on them and being able to turn while applying resin.

You'll get more help if you decide to do it . No point in wasting words yet.lol
That's the gist of it. Not hard at all if you have some epoxy experience. A steep learning curve if you don't, I would recommend finding a mentor to show you, if you fall into this category.

I have taught several guys with no experience in just a couple hours, hands on is simple. Trying to learn by reading can be daunting, but not impossible. Things like saying....thin epoxy a bit, when applying to tube first, about 5-10 %. If you see me do it, you can "feel" the difference when brushing it, and know exactly how to replicate.

There are several good you tube video's on glass work that can be used to figure out putting a sock on your tube.
I'm sure the link's will be supplied soon for you.

Good luck & enjoy your journey!

By the way I only added 6-7oz to my weight when I did mine...not including filler & paint
 
I have used the glass sock and the Kevlar sock, and I can say for sure, there will be lippage at the cone. I swapped to 6oz glass that you can get at automotive stores, usually packaged by the yard, before finally finding a role with about 15 - 20 yards on it at a work yard sale event. 6oz is a large & heavy weave that soaks epoxy well, but it leaves a weave pattern when cured. To fix this I veil the 6oz with a smaller light weight glass to cover the weave pattern. Very strong, and lighter than the sock... and the lip at the cone is quite manageable.
 
The "Easy Glass Sock" isn't really fiberglass but, a polyester fabric.
On 4" cardboard tubes; I also use 6 oz or equivalent. 1 to 2 layers is fine in most instances.
To finish it off, the top layer is: 2.3 oz fine weave satin cloth.


JD
 
Its here! The Velociraptor was delivered to my office this afternoon and it awaits my inspection right after my daughter's swimming lesson! Standby for in boxing pics!
 
Let the un-boxing begin!

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Glorious!

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Baffle system and drogue.

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E-bay components.

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Airframes, nose, transition and MMT.

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Upside down decals :). Still on the fence if I will use them. Nothing wrong with them it's just that I suck at getting decals right.

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A little suspenseful reading for the evening.

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54/1706 for the future K550!

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Electronics!

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And the obligatory dry-fit!

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So sick looking. I love the way that kit looks. I'd personally recommend not glassing it. Keep it light and you keep you options open.
 
Some minor updates today. I did a dry fit of all the tail cone assembly. I started by identifying and lying out all the necessary components.

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Then I found the CR for the tail. This is somewhat lesser in diameter than the only other CR provided so it couldn't be mistaken. I inserted it into the tail and pulled it up to the formed shoulder. Good fit inside the cone.

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Next I marked the MMT for the retainer.

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It seems like a lot of space between the end of the MMT and the inside edge of the retainer. Any opinions on this? Since I am not planning on using motor ejection, I'm not overly concerned with the retainer coming off but I want to make sure there is enough bonded surface area.

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Next, I inserted the MMT until the retainer was against the tail cone.

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Next, I marked the forward CR for eyebolt mounting. Since I am not planning on motor ejection for this, ever, I may not install this eyebolt but since I am a free man, I'll keep my options open for the moment. I test fit this CR on the forward end of the MMT. The fit was not good initially but after a couple of passes with the old knife we were in business.

ImageUploadedByRocketry Forum1438215374.389465.jpg

I also started messing around with my 54mm tapped closure. I had a 5/16-18 bent eyebolt handy so I threw her on for fun.

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Two things here. I do not want to use bent eyebolts so I plan to replace this with a shouldered forged version. Second, my stupid self put a steel split washer against an aluminum part. When I loosened the nut, this was the result:

ImageUploadedByRocketry Forum1438215410.434986.jpg

Anywho, this is where are for now.

ImageUploadedByRocketry Forum1438215476.055875.jpg

Also, along with my decision to use shouldered forged eyebolts, I will be replacing the supplied e-bay eyebolts with u-bolts for force distribution.

I am trying to think of a creative way to do internal fin fillets on this build but short of drilling holes in the tail, I am at a loss. Because I want to fly on the thrusty K550, I really think good internal fillets are mandatory.

Now I just need to make up my mind on epoxy and I'll be off and running.
 
When using a lock washer, always use a flat washer. That lock was probably only doing half its job of locking; So besides chewing up the end of the bulkhead, it could also spin loose after deployment... I know, as I lost a 38mm hybrid to just such an issue; booster spun itself right off the end of the eyebolt. Booster and motor never to be found again (by me anyway).

The build has started! That is excellent, as this is one beautiful rocket ship!
 
It seems like a lot of space between the end of the MMT and the inside edge of the retainer. Any opinions on this? Since I am not planning on using motor ejection, I'm not overly concerned with the retainer coming off but I want to make sure there is enough bonded surface area.

IF YOU INSERT A MOTOR, YOU WILL FIND THE CLOSURE TAKES UP THAT SPACE.


Two things here. I do not want to use bent eyebolts so I plan to replace this with a shouldered forged version. Second, my stupid self put a steel split washer against an aluminum part. When I loosened the nut, this was the result:

AS MENTIONED ALWAYS USE A WASHER BETWEEN ALUMINUM & A SPLIT-WASHER.

I am trying to think of a creative way to do internal fin fillets on this build but short of drilling holes in the tail, I am at a loss. Because I want to fly on the thrusty K550, I really think good internal fillets are mandatory.

GLUE MOTOR RETAINER/REAR CR IN PLACE WITH MOTOR MOUNT TUBE, JUST FIT TOP CR ON WITHOUT GLUE. [the one that goes on top of back fins]
TACK YOUR FINS ON THROUGH SLOTS, WHEN EPOXY CURED.....REMOVE THE TOP CR AND NOW YOU HAVE ACCESS FOR INTERNAL FILLETS. BE SURE TO PUT A SCREW OR 2 INTO THE CR, SO YOU HAVE '"HANDLES" FOR REMOVAL. IF THERE IS NO MIDDLE CR, JUST INSERT/REMOVE FROM AIRFRAME AFTER TACKING REAR FINS IN PLACE....FOAM THE BOTTOM SET & CONTINUE FROM THERE.

WHEN DOING TAILCONES...I USE 2-PRT FOAM INTEAD OF GLUE. JUST FILL THE SPACE BETWEEN FINS & IT WILL LOCK THEM IN PLACE. REALLY HARD TO GET TO BOTTOM WHEN DOING FILLETS, THAT AREA IS JUST SO TIGHT IN THERE. CAN BE DONE--FOAM IS JUST EASIER & JUST AS ADHESIVE AS EPOXY IN THIS CASE.

Have fun with this build, Mike makes REALLY nice kits & this is one of his"showcases".

Take your time & enjoy the journey!

PS By the way..... don't the instructions cover the internal fillet issue? You can also for-go drilling holes to inject, and just use round file...insert in slot...file half hole on each side of slot, inject through these, then fillet will cover them. One half hole filed on each slot will suffice, having done this myself.
 
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Have fun with this build, Mike makes REALLY nice kits & this is one of his"showcases".

Take your time & enjoy the journey!

PS By the way..... don't the instructions cover the internal fillet issue? You can also for-go drilling holes to inject, and just use round file...insert in slot...file half hole on each side of slot, inject through these, then fillet will cover them. One half hole filed on each slot will suffice, having done this myself.

I've read the instructions, and talked to Mike Fisher about the internal fillets, and was told that they are not needed. If you analyse how it's built, you'll find that it's not possible w/o drilling (due to the length of the motor tube).
 
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That said, if you were to go out of sequence with the assembly, and notch the centering rings, you could build and fillet the aft fins, then glue the boat tail to the back of the fin can, then glue the main fins (and fillet them too) before sealing the forward-most centering ring's notches.

Another thing to keep in mind, the fins will not likely undergo much stress when landing. They are well above the back of the rocket, and the main "hit" will be on the motor retainer. What's more, the way that the Vraptor "breaks" for the drogue (or main deployment) much of the airframe ahead of the fincan is removed, thus reducing landing stresses even more.
 
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You can internal fillet by drilling a few strategic holes in the boat-tail ring, or inject expanding foam. Or just follow the directions which proves a method of self filleting by coating the root and seating it against the motor tube several times. This makes a complete bridge and squeezes out the excess which flow into fillets.

The Velociraptor has flown on 54mm L motors with that method, no glass needed. For your motor mount tube, here's a trick I've never seen mentioned: You can also take the gloss off of the motor tube by dampening a cloth in water and wiping the glassine then let fully dry. This allows the epoxy to stick better without peeling the glassine off which changes the tube dimensions.
 
When using a lock washer, always use a flat washer. That lock was probably only doing half its job of locking; So besides chewing up the end of the bulkhead, it could also spin loose after deployment... I know, as I lost a 38mm hybrid to just such an issue; booster spun itself right off the end of the eyebolt. Booster and motor never to be found again (by me anyway).

The build has started! That is excellent, as this is one beautiful rocket ship!

This was an ultimate :facepalm: for me as I have years of construction experience. Total rookie mistake.
 
You can internal fillet by drilling a few strategic holes in the boat-tail ring, or inject expanding foam. Or just follow the directions which proves a method of self filleting by coating the root and seating it against the motor tube several times. This makes a complete bridge and squeezes out the excess which flow into fillets.

The Velociraptor has flown on 54mm L motors with that method, no glass needed. For your motor mount tube, here's a trick I've never seen mentioned: You can also take the gloss off of the motor tube by dampening a cloth in water and wiping the glassine then let fully dry. This allows the epoxy to stick better without peeling the glassine off which changes the tube dimensions.

Thanks! I'll give that a shot.

You don't happen to have any flight data from an L flight do you? I'd be interested to read them.
 
You can internal fillet by drilling a few strategic holes in the boat-tail ring, or inject expanding foam. Or just follow the directions which proves a method of self filleting by coating the root and seating it against the motor tube several times. This makes a complete bridge and squeezes out the excess which flow into fillets.

The Velociraptor has flown on 54mm L motors with that method, no glass needed. For your motor mount tube, here's a trick I've never seen mentioned: You can also take the gloss off of the motor tube by dampening a cloth in water and wiping the glassine then let fully dry. This allows the epoxy to stick better without peeling the glassine off which changes the tube dimensions.

I must try this when I build the raptor this winter... peeling the glassine is a pain sometimes.

This was an ultimate :facepalm: for me as I have years of construction experience. Total rookie mistake.

Yep, I know what you mean, one of "I Hate When That Happens..." especially when it is me that it happens to.
 
I wonder if I could score a Velociraptor if I set up a "Go Fund Me" account :wink: Man I love this rocket.
 
Mike, could you share the finishing tips on the nose cone and the tail cone?

I sand with a random orbital 120 grit till fuzzy, hit with a layer of primer, sand the fuzz off with 220, rinse and repeat until smooth, then paint.
 
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