Falcon 54 extreme minimum diameter build

Today I cut a hole in the top of the oven to put my other heater, and as soon as I plugged it in, it decided to short after 1 year of it working perfectly. Upon taking the casing apart I found that a flange of metal inside the heater is bent towards the wires and had cut through one of the wires insulation, causing it to short on the flange of metal.



I will probably buy another one of the same model specifically because the hole is cut for the exact size and shape of this heater, but I will just take the case off the side and bend that flange the other way. I think those wire nuts are some sort of resistor, so I don't think it would be the best idea to just cut the wires and solder them together. The green wire was attached but I just unscrewed it.

The one blower heater I have would only bring it to 180 degrees F.

Here is the product listing for it on amazon to show what the heater is:
https://www.amazon.com/gp/product/B00667DVB6/ref=ox_sc_act_title_3?smid=ATVPDKIKX0DER&psc=1


Update: Heater is ordered.

I think you will find the white things on the wires are just joiners, although it is a bit unusual to see them filled with something like they are. They normally have an internal screw thread so they are twisted onto the wires that are twisted together. Provides mechanical force and insulation for the joint.

OverTheTop said:

I think you will find the white things on the wires are just joiners, although it is a bit unusual to see them filled with something like they are. They normally have an internal screw thread so they are twisted onto the wires that are twisted together. Provides mechanical force and insulation for the joint.

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Ok. I thought they looked like wire nuts, but I had not seen the cap on the bottom before. I will try to cut them off and just solder it all. It might work if the carbon filament is okay, which it looks to be.

I don't have time to make a proper update, but I wanted to let you peeps know I have gotten the rocket laminated and I have a couple coats of west systems on it to fill the fibers to make it smooth. I have to sand it a bit more to get it smooth, but it is 90% there.

I have a second coat of JB weld on the NC tip for reinforcement and heat protection.

I have the Av-bay sled complete, I just epoxied the new bulkheads today. I need to install the threaded rods but that is all. A couple more late nights and I think I will be able to launch at High Skies in July on the 6th.

Okay, big update time.

Cutting the Carbon:


I used the cardboard as a template for the tape.

In the bag with the vacuum pulled:



Results:


After sanding off the excess and smoothing it out a bit, I layered on some west systems to sand and fill the fibers.

Before sanding the JB weld:

The nosecone is on it's second coat of JB weld. I am happy with the heat protection I have given it. It has 2 coats of Duralco 4460 (the epoxy used to laminate the fins) as well as two coats of JB weld over that on just the tip. I am curing in the oven on low temp the one coat of west systems epoxy I just painted over it all to make it smooth.

Nice build. What is the expected top speed?

OverTheTop said:

Nice build. What is the expected top speed?

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Mach 2.7 using the last builds mass. Hopefully this is roughly the same, I haven't weighed it yet. I am just working furiously to finish it in time, trying to get the paint on today.

The Falcon 54 Extreme is now complete.

Shots prior to painting, on the paint stand. All three fins are shown so you can inspect all my work. I have a lot to learn when it comes to laminating, but I am very happy with how it came out.





I am spraying Dimension acrylic enamels from Sherwin Williams Automotive with an Iwata RG3L spraygun. Technically it is just a very big airbrush because of its cone shaped spray pattern. I have a very under powered compressor for it, but it works if you just wait while the tank refills.






This is the complete rocket. It got one coat of ACME Finish 1 urethane clear coat, and then I went at it with 900 grit, then 1500 grit and then an orbital sander with microfiber cloth and cutting compound, then polish.


There is a gap there because of the recovery equipment. Once the shear pins are in it will hold it together.





Recovery setup. I have all the quick links on the shock cord as some nose weight. Without them it would have a stability margin of 0.82 cal, with them the margin is 1.23 cal.



Av-Bay setup. Big thanks to BryRocket for designing and printing the sled.



Mobius Mini and Additive Aerospace screw switch.




Time for sim details. The predicted altitude is 31,171 feet with a top speed of 2553 fps (Mach 2.26). The mass of the rocket without the motor is 1622 grams.

All that is left to do is tap the shear pin holes and test the ejection. I think I will use three 4-40 shear pins instead of the three 2-56 to hold the rocket together in flight. I have to take a look at what I have, I might be out of 4-40 shear pin though, in which case I will just use 6 2-56 pins for the nose and body.

My plan is to fly around 1:00 so it is as hot as possible. It will suck for recovery, but the higher density altitude will reduce drag a lot, helping with altitude. There are roads I can drive to try and get closer, but that is limited. The launch site is in the Pawnee National Grasslands in Colorado. The land is run by the US forest service and we launch with a special use permit. They wont even allow us to use ATV's for fire safety, so I can't just go driving across the land.

I will update this on the day of the launch to let you guys know the results

-Matthew

No go on the launch today. The wind was too high and too much cloud cover for me to fly. Others were and I had a great time watching. I will fly tomorrow as the forecast os much better.

Bad news yet again. I got it on the pad, everything was prepped and ready, so I go to turn on the camera. I see that it is showing a red, yellow, and red light flashing in unison. I take it back to the flight line and get it out. It turns out the shutter switch had broken off. I have no idea how or when it happened, but I was pissed. I could have flown, but there would be no video from it. Since the whole premise of this flight is to get the on board footage and I don't have a spare $200 for another L935, I decided to scrub the launch, get a new camera and fly next month.

Everything is set up and installed, ready for August 10-11. We just need a green light from the forest service to fly.

The surface mount switches on the Mobius Mini are extremely weak I found while I was mounting the new board. I accidentally pushed on one while I was setting it in the mount and it broke one of it's solder locations. Luckily I was able to solder it back and checked everything was working. I added some extra solder to each switch to reinforce it. I am thinking I will drop a little west systems around the switches to make certain they will not come off. I have heard of people coating electronics in epoxy as water proofing, is this correct? I want to double check because I don't want to ruin my camera.

I think I might try to build a better launch tower than the one my club has. It is only 48" long and I need to have as straight of a boost as possible, so I might pick up some 8 ft aluminum tube and make a launch tower with threaded rod. I doubt will have time as I am struggling to catch up on math homework after taking some extensions on assignments to get this project done, along with me working 30 hours a week.

The club tower is assembled with bike wheels and threaded rod, so I might be able to just get longer rods to use with it.

mperegrinefalcon said:

I added some extra solder to each switch to reinforce it.

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Mechanical reinforcing may be better. Solder is not good mechanically.

mperegrinefalcon said:

I have heard of people coating electronics in epoxy as water proofing, is this correct?

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I have been known to conformally coat my avionics. I usually use Electrolube HPA or similar. It is relatively easy to remove if needed. Can get that sort of stuff from some electronics supply stores. Be careful to not get the coating in switches, buzzers, barometers and connectors. If you have a UV torch you can inspect where the coating has gone, since it fluoresces. I find application by brush works well and you are less inclined to get it where it is problematic. Spray into the cap and then apply the liquid with a brush.

Not sure about coating a camera. You would need to make sure the fumes as it cures don't degrade the optics or fog up the CID or other sensor. Tread carefully...

OverTheTop said:

Mechanical reinforcing may be better. Solder is not good mechanically.


I have been known to conformally coat my avionics. I usually use Electrolube HPA or similar. It is relatively easy to remove if needed. Can get that sort of stuff from some electronics supply stores. Be careful to not get the coating in switches, buzzers, barometers and connectors. If you have a UV torch you can inspect where the coating has gone, since it fluoresces. I find application by brush works well and you are less inclined to get it where it is problematic. Spray into the cap and then apply the liquid with a brush.

Not sure about coating a camera. You would need to make sure the fumes as it cures don't degrade the optics or fog up the CID or other sensor. Tread carefully...

Click to expand...

Yeah, I won't risk that, and I don't need to waterproof it. I am just wondering if a drop of epoxy around the switches will harm them or short something. The West Systems without anything added shouldn't conduct electricity, correct?

Correct. WS should be fine in that situation. Just make sure it doesn't run into the switch mechanism .

Hey peeps,
We are go for launch!
I am packing up today and leaving around 3 or 4 ish. I like hanging out up there on the plains so I go early. It is a great break from the suburbs

Back from the launch.
Up part worked great.
Apogee callout.
Max altitude 27,320 feet
Max speed 2660 fps
Keeps accelerating.
Last packet was 3091 feet 803 fps.

The rocket landed 2.5 miles bearing 119 degrees from the launch site. Drive up the road that goes 1 mile south of the launch site then turn left on an east west road. It lawn darted into the ground about 500 feet from the road, in the middle of the yard of the only house for miles around. I **** you not. Only about 800 feet away from the landowners llama, whose name is Mac. I am very glad my rocket did not hit Mac, or especially this guys house. This could have killed either of them with ease or significantly damaged his property.

I saw the rocket flower sticking out of the ground from the road. I went up and knocked on this guys door and explained what had happened. Surprisingly he thought it was funny. He knows the club launches up there, and have been for 25 years. This is the first time anything had happened. The landowner reflected that he hear a loud pop earlier, which would have been the main parachute charge. The nosecone shot off and all the kevlar ripped and flew away. The parachute was not in site and assumed to be completely shredded.






Nothing except the nosecone on this rocket was recoverable. Motor case is bent, tailcone closure fused into the case. This is how I pulled the Av Bay out of the ground:

As you might be able to see, the fiberglass coupler and some body tube has been turned inside out, along with the 3/32" bolt being bent back in a U shape.

Closer look inside:


Bulkplate cracked in half.

The end that impacted the ground:



End of the rocket and some of the case damage:

Wow. Ouch. Anything recoverable from the camera?

Was an impressive launch! It left the tower kinda fast, at least I caught that pretty imax flame...

Sawed open the av-bay and:



The heat from the pressure melted the plastic into a new piece.

I will try to do some surgery to find the SD card, it is a minuscule chance, but maybe the thing survived.


I am very glad no property, people, or llamas were harmed by this rocket. I apologized profusely to the property owner, but he seemed fine about it. The chances that this landed where it did were minescule, but terrifying to think about what it COULD do if it hit.





I will build a new one better with what I have learned.

The list of things I want to do differently:
I will use thinner fins. I will make them out of 2mm thick 0/90 degree plate laminated with 3 consecutively larger layers of unidirectional carbon fiber so the fin tapers to the tip.

I can cut out the smoke grain on the new motor and drill through it and fill the hole with epoxy and a washer, and attach an eyebolt to it. I will friction fit the motor with tape, and anchor the shock cord to the aforementioned modification. This will reduce mass and I can cut 2" off the airframe.

I will ditch the switch band and only have the coupler and shear pins, or I will build a chute cannon in the nosecone and have the cone come off, then the chute cannon go off for the main. This is still subject to change of course. I want to try and have only one airframe seam.

I am thinking I will use a carbon fiber air frame with a fiberglass nosecone.

I am going down to 3/32" 700# kevlar with 15 feet for each, depending how I do it.

Build my own 6 foot tower.

This might be a little while off as I pretty much need to buy everything again and play around with configurations.

gfunk said:

Was an impressive launch! It left the tower kinda fast, at least I caught that pretty imax flame...

View attachment 389976
View attachment 389977

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Holy Crap, That is AMAZING!!!! I am so happy you managed to get that. I am working on getting the video uploaded.

This decelerated from 600+ mph to 0 in about 22" of rocket. How can I calculate the G force on landing?

mperegrinefalcon said:

Sawed open the av-bay and:
I will build a new one better with what I have learned.

The list of things I want to do differently:
I will use thinner fins. I will make them out of 2mm thick 0/90 degree plate laminated with 3 consecutively larger layers of unidirectional carbon fiber so the fin tapers to the tip.

I can cut out the smoke grain on the new motor and drill through it and fill the hole with epoxy and a washer, and attach an eyebolt to it. I will friction fit the motor with tape, and anchor the shock cord to the aforementioned modification. This will reduce mass and I can cut 2" off the airframe.

I will ditch the switch band and only have the coupler and shear pins, or I will build a chute cannon in the nosecone and have the cone come off, then the chute cannon go off for the main. This is still subject to change of course. I want to try and have only one airframe seam.

I am thinking I will use a carbon fiber air frame with a fiberglass nosecone.

I am going down to 3/32" 700# kevlar with 15 feet for each, depending how I do it.

This might be a little while off as I pretty much need to buy everything again and play around with configurations.

Click to expand...

And figure out why nothing deployed at apogee!

Tony

tfish said:

And figure out why nothing deployed at apogee!

Tony

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I don't think I will ever be able to figure that out. I am going for a looser fit, and a smaller shock cord. I am going to drop down to 3/32" cord to make room for everything and reduce weight. I don't need 1/4" for this. I put the igniter at the top of the powder, packed in some dog barf on it, then wrapped it with 3 layers of masking tape. It was a 1.2 gram charge in 4" length of 54mm tube, with 3 4-40 pins. I tested with 1 gram and it worked great, so I added a 20% margin of safety so in case it didn't all go off. I always do a pull test too. It must have been the altimeter I am thinking. I will probably go for adding a raven with the telemetrum. I will also change to a magnetic switch from Featherweight to reduce the number of holes.

mperegrinefalcon said:

I don't think I will ever be able to figure that out. I am going for a looser fit, and a smaller shock cord. I am going to drop down to 3/32" cord to make room for everything and reduce weight. I don't need 1/4" for this. I put the igniter at the top of the powder, packed in some dog barf on it, then wrapped it with 3 layers of masking tape. It was a 1.2 gram charge in 4" length of 54mm tube, with 3 4-40 pins. I tested with 1 gram and it worked great, so I added a 20% margin of safety so in case it didn't all go off. I always do a pull test too. It must have been the altimeter I am thinking. I will probably go for adding a raven with the telemetrum. I will also change to a magnetic switch from Featherweight to reduce the number of holes.

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Sorry about the down part, it's never nice to lose a vehicle. With regards to your deployment issues, considering you were still receiving telemetry from your TeleMetrum on the way down I don't think it would be the root cause for your failed apogee deployment. What did you use to contain your apogee charge?

For what it's worth I think you probably had a combination of issues around your BP charge not fully igniting due to the altitude you reached combined with too many shear pins that were also too big. My last MD L935 flight used one 2-56 nylon screw and worked a treat. granted it was single break but it went over Mach 2.6 and the head of the shear pin actually melted during boost and yet it still held the airframe and nose cone together. I also used an aluminum "cannon" to house my apogee charge.

YMMV but if I were a betting man that's where I'd put my money.

That coupler extended pretty far into the airframe. I am not sure what others get away with, but as a piston, unless the vent hole was plenty big, and if the charge was not at full power, that much length would create a bit of vacuum which would cause resistance to the separation.


That is a sinking feeling, walking up to a newly built bird sticking in the ground like that.

plugger said:

Sorry about the down part, it's never nice to lose a vehicle. With regards to your deployment issues, considering you were still receiving telemetry from your TeleMetrum on the way down I don't think it would be the root cause for your failed apogee deployment. What did you use to contain your apogee charge?

For what it's worth I think you probably had a combination of issues around your BP charge not fully igniting due to the altitude you reached combined with too many shear pins that were also too big. My last MD L935 flight used one 2-56 nylon screw and worked a treat. granted it was single break but it went over Mach 2.6 and the head of the shear pin actually melted during boost and yet it still held the airframe and nose cone together. I also used an aluminum "cannon" to house my apogee charge.

YMMV but if I were a betting man that's where I'd put my money.

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That is a good point on the altimeter, after all the main charge worked to fire off the nosecone.

I used a 1/2" PVC endcap with a hole drilled in its side and attached with a length of 1/8" kevlar tied to it. I fill the hole with CA glue to also hold the Kevlar. I usually get them back and I have done all my DD flights with these kinds of charges.They just rest in the tube. I have done a 40 gee launch with these kinds of charges before, and this only simmed to roughly 30 gees. I will drop down to 2/56 pins, and maybe build in a ring on the bottom to support it the av-bay. I want to ditch the switch band, but I have to think about the acceleration and deceleration. Or I can just have a chute cannon in the nose. Getting that packed would be a pain and I don't know if everything would fit through. Hmmm...

https://compositeenvisions.com/carb...-directional-hexcel-im2-intermediate-modulus/

Have any of you used this company before? What about this material?

I am thinking I will use either this plate:
https://www.clearwatercomposites.com/products/carbon-fiber-plates/std-mod-carbon-fiber-plates/

This is 2mm plate. I would do the 3 layers of the unidirectional fibers layed up horizontally on this.

Or this plate: https://www.rockwestcomposites.com/...-fiber-plate/carbon-fiber-uni-plate/103-group

The second one is only 1.4mm and I would make sure that the fins are cut so the direction of fibers align with the rocket body as it is uni-directional to provide rotational stiffness, then the lamination would be 4 layers of unidirectional fibers going horizontally.

Either way I do it, I will layer the carbon with smaller pieces underneath and then build it up so that I get fins that taper to the tip. I will only do one layer that is entirely tip to tip over everything else.

mperegrinefalcon said:

That is a good point on the altimeter, after all the main charge worked to fire off the nosecone.

I used a 1/2" PVC endcap with a hole drilled in its side and attached with a length of 1/8" kevlar tied to it. I fill the hole with CA glue to also hold the Kevlar. I usually get them back and I have done all my DD flights with these kinds of charges.They just rest in the tube. I have done a 40 gee launch with these kinds of charges before, and this only simmed to roughly 30 gees. I will drop down to 2/56 pins, and maybe build in a ring on the bottom to support it the av-bay. I want to ditch the switch band, but I have to think about the acceleration and deceleration. Or I can just have a chute cannon in the nose. Getting that packed would be a pain and I don't know if everything would fit through. Hmmm...

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Given you can't easily dump the eeprom file from your flight off your Telemetrum your best bet is to perform quite a granular analysis of the telem file from your phone. So email yourself the telem file stored on your phone and then replay the flight in AltOS on your computer. I normally only ever deal with TeleGPS from a telemetry perspective but I expect you can "see" the Apogee and Main charge status in the flight replay. Given your issue was with your apogee charge not separating the rocket (?) you should be able to see the charge lose continuity in the replay just past apogee.

Also, to confirm, your apogee charge fired but didn't separate the AV bay/NC from the airframe? And yet you still had NC sep with the main charge while coming in ballistic? That definitely sounds like an apogee charge issue that you can most likely eliminate as altimeter based if you replay the flight. It would also eliminate any suspicion regarding gees causing your apogee charge to lose continuity as I expect if that was an issue it would have occurred during boost.

Finally, maybe next time change the call sign on your TeleMetrum? When you leave the settings as default you're opening yourself up to overlap if someone else is also operating with the same call sign and channel. Years ago we had a guy frantically running up and down the flight line yelling at people who owned TeleMetrums to turn theirs off as he was racked up ready to launch and his base station kept reporting the rocket had landed. Come to find our another club member was leaving in an RV with their TeleMetrum still chirping away post flight. It was quite the funny scene.