Winter Build Kits Have Arrived

[ckreef]

My two winter build kits have arrived. I am very excited and can't wait to get one flying :jaw:

The Gamma Star came with all the wood in prepackaged bags. Some other parts bags, instructions and full size plans. This build is going to take some time to complete as there is a lot of wood :y:

The Strato Blaster came NIB condition. The wing cores look good with no warps. The small parts bags came in unopened condition. The plywood looks good and not warped. I have not inspected all the balsa, will wait to inspect it when the build starts. I will build this kit first as it looks to be a much easier, quicker build.

I need to go back and carefully re-read Mr-Matt's F & G build thread.

I am also going to contact FlyingFoam and see if they can cut me an additional set of wing cores. There service is fairly cheap and that way I can leave the original cores intact.

I also need to explore the fiberglass fuselage idea. I have never done fiberglass molds before but I can definitely see the advantage.

If I can get replacement wing cores and fuselage I could buy all the rocket parts and cut my own wood (not a lot of wood to cut) leaving this kit in it's NIB condition. Something to consider anyway.

I do have an 11 day X-mas vacation coming up but I have promised to take my son down to my Mom's house for X-mas this year (7 days). Do I really need to keep my promise ??? Is it wrong for me to even think that way :eyepop:

 

[mmmdowning]

Those are really cool, are you going to show the build?

 

[ckreef]

Those are really cool, are you going to show the build?

Will do my best with a separate build thread for each kit. This may not start till after X-mas break as I am bleeding money for this and X-mas at a rapid rate. Also I need to buy some more items but my wallet really needs a rest.

 

[mr_matt_II]

The both are nice but the gamma star is a very well engineered kit with excellent plans and instructions.

Be careful with my stratoblaster mods, these were made to make sure it came out less than 500 grams (and fly big motors). Don't complicate the build if you don't have to.

How are you getting the airfoils for flyinfoam?

 

[ckreef]

How are you getting the airfoils for flyinfoam?

Well that has been a brain challenge. To do it right I had to take into account the LE cap, TE cap, TE/aileron stock and don't forget the sheeting thickness. Add all measurements up and submit the dimensions. Also had to supply the wing sweep measurement for the proper angle cut. Fortunately I have a really good set of original wing cores to measure by.

Earlier tonight I put in for a wing core quote (waiting for a reply). Taking measurements off the original airfoils they seem to be close to NACA2412 foils. Anyway will order one set and compare it to the originals. If it's close will use it, if not will tweak and order another set.

 

[ckreef]

I woke up this morning with the realization that my calculations were flawed. The NACA2412 has a max thickness of 12% of the cord which would produce a wing that would be about 3/16" too thick. I really need a thickness of about 8.77% to get a wing that will correctly fit in the cutout. So I'm going to send flying foam a revised quote using the RG15 airfoil which has a thickness of 8.92%. Not perfect but should be usable.

I do realize the only correct way to do this is to know the exact airfoil Estes used but I doubt that information is available.

 

[mr_matt_II]

I woke up this morning with the realization that my calculations were flawed. The NACA2412 has a max thickness of 12% of the cord which would produce a wing that would be about 3/16" too thick. I really need a thickness of about 8.77% to get a wing that will correctly fit in the cutout. So I'm going to send flying foam a revised quote using the RG15 airfoil which has a thickness of 8.92%. Not perfect but should be usable.

I do realize the only correct way to do this is to know the exact airfoil Estes used but I doubt that information is available.

Be careful. The finished airfoil is not the shape of the cutout. The cutout has a funny shape that let's you wedge the finished (joined) wing through the fuselage. There are gaps you have to fill between the wing and the fuse after the wing is installed.

Also the booms are cut to match the airfoil and Estes does not give you incidence angles to check against so you need to be careful that you revised airfoil won't mess the tail mounting up.

Why not just trace the outlines of the cores?

 

[ckreef]

Why not just trace the outlines of the cores?

Thank you mr_matt for the warnings.

I thought about just tracing the outlines of the cores but that increases the cost of the replacement cores. Using a std. airfoil will keep the cost down. I think I have a foil that should be really similar to original and I will compare it to the original before I continue with the build.

Any other suggestions are welcomed, especially in order to keep the weight at the bare minimum.

I agree with you that the original way of linking the ailerons sucks. Once you link up the ailerons and then epoxy the engine mount you can no longer access the aileron linkage. That won't do. I've been considering a slightly revised version of your method. I also have been toying with the idea of a single Aileron servo but with adjustable linkages that you can actually access. (The idea is forming in my head as I type

I'm good at building and kit bashing so this project is right up my alley.

 

[Aero B]

Nice kits!
I have been flying RC almost as long as rockets.
It's about time to mix the arts I think!

 

[mr_matt_II]

I thought about just tracing the outlines of the cores but that increases the cost of the replacement cores. Using a std. airfoil will keep the cost down. I think I have a foil that should be really similar to original and I will compare it to the original before I continue with the build.

TLAR (That Looks About Right) should be fine in this case! I was a little stumped why flyingfoam would charge more as there are no templates for them to make (they use CNC cutters), then I looked at their site again. They charge for digitizing the airfoil, so if you do that yourself they would not charge you (you would have to use Illustrator, or Corel Draw. I think Compufoil would let you do this as well.)

Any other suggestions are welcomed, especially in order to keep the weight at the bare minimum.

Well the basic issue is a design suitable for 20 year old radios. These newer servos are maybe 1/2 as heavy as the older servos. Combine this with lighter modern batteries and receivers and now the plane is tail heavy. Then you end up having to use ballast. After I all went through, I still had to add 17 grams of noseweight. You might end up with much more than that, it all depends on where you mount the elevator servo.

You are using the 24/40 RMS, IIRC? That is pretty light.

I agree with you that the original way of linking the ailerons sucks. Once you link up the ailerons and then epoxy the engine mount you can no longer access the aileron linkage. That won't do. I've been considering a slightly revised version of your method. I also have been toying with the idea of a single Aileron servo but with adjustable linkages that you can actually access. (The idea is forming in my head as I type

.

Well I don't know how you can get a single aileron servo in there, but my motor mount is even bigger (32mm) so maybe I just can't picture it. Servos in the wing is not too hard to do and it lets you run flaps or crow if you want, helpful for spot landings.

The biggest thing you will need to decide is where to put the elevator servo. I think where I put it is best for a slop free linkage, but can make it easier to flutter the whole tail (because of the large mass right in the middle of the elevator). I would likely put it somewhere else if I did it again, or just don't run G motors!

My second option was to put the servo in a widened boom with a shorter linkage. I don't like the idea of cutting the wing skin to rout the snake....for that matter I don't like the idea of running a snake on the elevator at all.

 

[ckreef]

TLAR (That Looks About Right) should be fine in this case!

TLAR was what I was thinking. I would say this is "NOT Rocket Science" but then again it sort of is :lol:

You are using the 24/40 RMS, IIRC? That is pretty light.

Yes Aerotech 24/40 RMS is what I am planning

Servos in the wing is not too hard to do and it lets you run flaps or crow if you want, helpful for spot landings.

This is how I like to do my planes so I guess this is what I need to do. Looking at how you did it has inspired me. I have a slightly modified idea where I might be able to shave 1 or 2 grams off a 12G servo.

The biggest thing you will need to decide is where to put the elevator servo.

Will get back to this at a later date.

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Matt, your help and help from others like Ari might just allow me to be successful in re-kiting the Strato Blaster. Stay tuned as I have many more questions coming up :jaw:

Will order the wing cores in the next few days. They will either be close or a waste of money --- I think they will be close (if I did my measurements/calculations correctly)

 

[ckreef]

I got my quote back from FlyingFoam today. Will order a set of wing cores tomorrow. In the meantime I am getting cut templates scanned into the computer so I can reproduce all the Balsa/Ply without issue. Strato Blaster Re-Kit is moving forward

 

[ckreef]

Ordered my wing cores on Friday. In about 7 business days they will go into that days cut queue. They will wait and charge my credit card once they get put into the cut queue. Finishing up on my parts cut templates and getting my other parts ordered.

Where is a few good places to buy rocket building supplies (motor tubes, adapter rings, etc...) ???

What does everyone think about Balsa USA and their quality of wood ???

 

[ckreef]

My wing cores from Flying Foam arrived today and I couldn't be happier :smile:

I guess I did my measurements and calculations correctly because they are really close to perfect. The airfoil is a smige fatter (I knew it would be) but that shouldn't pose any issues. The only thing I will need to do is cut my TE off but when I account for the wood and make the cut that should come out just right.

Pictured below is a comparison of the wing cores. The one on the right is the original and the one on the left is the core from Flying Foam still needing it's TE cut off.

 

[mr_matt_II]

My wing cores from Flying Foam arrived today and I couldn't be happier :smile:

I guess I did my measurements and calculations correctly because they are really close to perfect. The airfoil is a smige fatter (I knew it would be) but that shouldn't pose any issues. The only thing I will need to do is cut my TE off but when I account for the wood and make the cut that should come out just right.

Pictured below is a comparison of the wing cores. The one on the right is the original and the one on the left is the core from Flying Foam still needing it's TE cut off.

View attachment 107941

Looks great, they do good work.

I would not under any circumstances cut off the TE but sheet the wing with the TE on and then cut the ailerons out of the wing. Follow the instructions for the Phoenix if you want but it would not be hard. Shaping that TE material that they have in the kit is a true nightmare.

https://www.aerotech-rocketry.com/c...tructions/Kit_Instructions/phoenix_manual.pdf

 

[ckreef]

Looks great, they do good work.

I would not under any circumstances cut off the TE but sheet the wing with the TE on and then cut the ailerons out of the wing. Follow the instructions for the Phoenix if you want but it would not be hard. Shaping that TE material that they have in the kit is a true nightmare.

https://www.aerotech-rocketry.com/c...tructions/Kit_Instructions/phoenix_manual.pdf

Good call on that. Should not be a problem. Also thank you for the link. Looks like a few good ideas in that. Will read all the appropriate sections.

Going on vacation for X-mas so it will be shortly after X-mas before I can order a few more items and really start to work on this.

 

[mr_matt_II]

I had 5 more flights on mine this last Sunday, probably 12 flights in the last month. I have it pretty dialed in now on all of the 32 mm Aerotech motors

Only danger is the G-12 (8.5 second burn). You have to keep it going vertical, if you let it go horizontal it picks up too much speed. With the other motors you can maneuver a bit under boost and not overstress the airframe.

It should fly great on the Aerotech F-12 to F-24 24mm motors as well.

 

[ckreef]

Moving on with the project --- I just now ordered the following:

AT 24/40 RMS hardware
Aft wrench
extra ignitors
copperhead clip
E reload kit for rocket (see below) --- I have some Estes D motors to play with

12v controller
Maverick rocket (to play/test RMS system with)

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This weekend I still need to order:

Servos,
extension wires,
vacuum bagging supplies,
balsa,
and a few other items I haven't thought of yet

 

[ckreef]

Since I have never launched a RMS before I wanted to try it in a rocket first so I got a little distracted. I bought a rocket kit and when I opened the kit it was a big disappointment. So I loaded the parts into Openrocket and did some tweaking. When I had something I liked I did a quick build on it and a crappy paint job. I came up with a 2.6" x 21.5" rocket at 10oz launch weight.

Today I took it to my local rc field (small for rockets). The wind was about 8 - 10 mph but not to let that stand in the way of progress I angled the rod about 2 degrees into the wind and blasted it off anyway. I first used a Estes D12-3 just to make sure it was air worthy. I then did 2 more flights on a AT 24/40 E18-4W.

Below is a short video of my first RMS launch. Since this was successful I can now get back to working on this project

[YOUTUBE]PyATZbeuosI[/YOUTUBE]