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brywisco
19th March 2010, 06:24 PM
Please bear with my complete newby-ness to this hobby.

I would like to build and fly a rocket with my 8 year old son and at this point I have one main question. We live on a large lake and I was thinking it would be easy to launch and recover on the water vs having to travel to a large field. Is it feasible to build a 'waterproof' rocket that would float?

I was looking at the Edmonds Aerospace CiCi. I like the idea of a boosted glider. Could I just waterproof this baby with brightly colored paint etc.?

Thanks for your advice...

skycopp
19th March 2010, 06:33 PM
Unfortunately, I don't think it is possible to completely waterproof a rocket because of the amount of cardboard that goes into building one. But if you made one completely from plastic, maybe that would work.

RoyAtl
19th March 2010, 06:33 PM
Paint on most gliders is problematic. It adds a significant amount of mass, which means it probably won't glide as well. That said, if you paint it thoroughly, it should float and not be damaged by the water. The pod, however, is another story. Any rocket that ejects a recovery system, or has a black powder rocket motor (with clay nozzle and paper casing), is going to be very hard to waterproof.

brywisco
19th March 2010, 07:21 PM
Thanks for the replies!

The CiCi glider does not (I believe) have a pod. It looks to be a single unit made from balsa. I was thinking I could use a thin coating of polyurethane or maybe some thinned CA on it? Ideas anyone?
Are there any plastic rocket kits or plans available that you know of?

NjCo
19th March 2010, 08:08 PM
Thanks for the replies!

The CiCi glider does not (I believe) have a pod. It looks to be a single unit made from balsa. I was thinking I could use a thin coating of polyurethane or maybe some thinned CA on it? Ideas anyone?
Are there any plastic rocket kits or plans available that you know of?

I've never heard of anyone doing this but I like the idea of lake recovery as long as you have a boat standing by to make a quick recovery and you test the idea to see how well a rocket would actually float. You might need to add a flotation device to your recovery system to make sure you don't lose the rocket.

Instead of paint you might try waxing the glider. That might be lighter than paint. Adding a lot of weight to boost gliders can be problematic to say the least. You could also paint the outside of a boost pod and then apply a coat of Future acrylic floor wax to the outside and inside. That might seal the cardboard enough that little or no harm would be done before you could recover the rocket - which I would try to do as quickly as possible. Still, I'm not sure this will work so you might test it with a cardboard tube and see how it goes.

One thing you will have to worry about is the engine casing. Those are wrapped paper and you likely wouldn't be able to seal the entire thing and still get it into the engine mount. But I would at a minimum seal the ends of the engine. I'd also try to get the casing out of the rocket after launch as quickly as possible. If it swells in the water you might not get it out of the engine mount without ruining your rocket.

Sounds like an interesting problem that might just be doable.

NjCo
19th March 2010, 08:16 PM
Are there any plastic rocket kits or plans available that you know of?

I'm not sure there are any full plastic kits available anymore but there used to be a few many years ago. The closest thing would be the Estes RTF (ready to fly) and E2X lines (almost ready to fly). These I believe have cardboard body tubes but plastic nose cones and one piece plastic fins/engine mount units. Probably the closest you'll get and at least all you'd have to worry about would be the body tube. If you don't seal it all the way it would be fairly easy to replace.

brywisco
19th March 2010, 08:19 PM
Is the engine casing integral to the engine or is it a part of the rocket's body?
Again, I am a newbie to this, so forgive my ignorance here.
I think you are saying the engine itself could soak up water and swell inside the rocket. Is that accurate?

Could I build a standard (non-glider) rocket from plastic?

dedleytedley
19th March 2010, 09:15 PM
I had an unintended water recovery of my Saturn V:y:. I launch in areas of new construction and it drifted into a drainage pond. I stripped to my skivvies and went after it immediately so it only spent about five minutes in the water. I removed as much water as I could and left it to dry in the sun. I didn't build it so I can't say what coatings might be on it but it survived unscathed. If you don't leave a paper rocket in the water for very long it should be okay. Perhaps you could spray the inside of it with a waterproofing compound(silicone spray,etc.). The motor casing is separate from the motor tube and is a very tightly wrapped paper. It will soak with long immersion but not much over a short period. It's the motor tube, rings and inside of the body tube that will saturate fairly quickly if left untreated. A plastic rocket may melt or even burn from the ejection charge depending on what you use. Ted

BEC
19th March 2010, 09:33 PM
Some good basic info on the parts and how they fit together here: http://www.estesrockets.com/images/uploads/Rocketry101.pdf

Setting something up for water landings would be a bit challenging. I think an Estes E2X that has an integral motor mount/fin can assembly and which you could waterproof the body tube both inside and out with Future might work.... one that looks suitable is this one: http://www.estesrockets.com/store/rockets/kits/e2x/002181-chrome-domestm.html

The reason I suggest this one is that there is no motor mount tube and paper spacers as in a number of the E2X and ready to fly kits, which would be harder to waterproof than just the body tube as in the Chrome Domes. Also, the way the motor is retained would be less problematical for removing a water-swelled spent engine casing than the more traditional arrangement. I see the Dragonite, Metalizer and some other large E2X rockets also have the plastic motor mount setup.

On that basis stay away from all the 0.98 (BT-50) diameter RTFs or E2Xs as they have the thick paper rings/paper tube motor mount assembly (a "traditional" style motor mount) such as the Rascal/HiJinks/Athena RTFs or the Alpha III E2X kit.

Sounds like an interesting problem to solve.

brywisco
19th March 2010, 09:58 PM
Cool info...that helps alot.
It makes sense for my son and I to buy one of these E2X kits and then try to waterproof it. We would be launcing from our dock then could paddle out pretty quickly to retrieve.

ScrapDaddy
19th March 2010, 11:54 PM
One itty bitty problem on estes engines remember what it says if you want to destry them? And the paper casing will absorb the water and become near impossible to remove and the nozel will allow water to flood inti the rocket almost sinking it..... I would give you a recovery time of 10 secs tops

BEC
20th March 2010, 12:08 AM
Which is why I suggested the particular kits I did....they retain the motor in a different way that will be MUCH less susceptible to not being able to get a wet motor out of than a regular motor mount tube.

ScrapDaddy
20th March 2010, 12:26 AM
You know if that's the problem maybe they should switch to a composite motor like the D10 or D21

ben_ullman
20th March 2010, 12:59 AM
You know if that's the problem maybe they should switch to a composite motor like the D10 or D21

they also let water into the casing. But it wouldnt hurt the case.

Ben

Bone Daddy
20th March 2010, 01:33 AM
I too had an accidental water recovery. Fortunately it was more of a very large puddle than a lake, so it never was 100% submerged. It was however extremely cool looking even as I looked on with horror. The splash just felt right. The rocket was Dremel 1 which I posted under scratch built.

Anyway, the rocket came out fine after I shook the water out and dried it. The problem, as alluded to above, came when I did not remove the motor immediately on retrieval. When I got home and tried to remove it, the motor had swelled to the point it could not be removed. I ended up having to remove the whole motor mount.

With that said, I've been considering a planned water landing, with no intention of retrieving it. The rocket would either be a newly built throw away, or one that is ready for the scrap heap anyway.

ScrapDaddy
20th March 2010, 03:05 AM
they also let water into the casing. But it wouldnt hurt the case.

Ben

Exactly phelenic doesn't react to water and the tube would be flooded with the parachute opening

MarkII
20th March 2010, 03:11 AM
I'm wondering if a large saucer would work. Make it out of foam core and seal all of the surfaces. Insure that the seams are water-tight, and use a plastic launch lug (such as a Bic Stic pen barrel) inserted through the upper and lower shrouds. Make sure that all seams are water-tight. Make the motor tube out of something waterproof instead of using one made out of kraft paper (fiberglass, maybe?), and make it a bit larger than the diameter of the rocket motor. Make sure that all of the seams are water-tight. Then retain the motor via friction-fitting, using a good amount of tape. The saucer design will float naturally (make sure that all of the seams are water-tight) and there will be no recovery device to complicate things. Because the motor is retained by a thick layer of tape, if (when) it soaks up the water and swells, it will still be possible to remove it. If it is flown on an Aerotech single use motor, a water-logged, swollen motor case won't be an issue. (I'm not sure about Road Runner motors because I have never seen any, but I think that they would probably have that advantage, too.)

Oh, and don't forget to make sure that all of the seams are water-tight.

An Art Applewhite Delta Saucer or Cinco, for instance, could be make sea-worthy, especially if some of the parts are re-fabricated out of water-proof (or water-proofable) materials. Properly sealed, both designs would no doubt float well.

Mark K.

ScrapDaddy
20th March 2010, 03:22 AM
I Think The OOP Estes Snitch might fit the bill but im not sure what its made of

NjCo
20th March 2010, 03:25 AM
A FlisKits Decaffeinator, Espresso or a UFFO would also work since they are all made of foam drinking cups.

http://www.fliskits.com/products/01prod_fs.htm

BEC
20th March 2010, 03:40 AM
Building on what Mark II wrote - fanfold foam or Depron saucer makes lots of sense. With no paper layer there'd be no need to worry about sealing seams.

I'm sitting here trying to think of what sort of readily available tubing could be used as a motor mount - particularly if one could create one that wouln't have the stuck motor case problem......I'm sure there's something.

There were four Estes Snitches at my club launch a week ago - they look as if they're molded from polypropylene. One would just have to make sure it floats before trying it....

ScrapDaddy
20th March 2010, 03:42 AM
A FlisKits Decaffeinator, Espresso or a UFFO would also work since they are all made of foam drinking cups.

http://www.fliskits.com/products/01prod_fs.htm

dont forget about the Expresso ;)

Handeman
20th March 2010, 04:38 AM
You might want to contact the guys in Lakeshore Area Rocketry Society in Manitowoc WI. IIRC they do a launch from the pier every year where all rockets land in Lake Michigan. I'm sure they can give you lots of tips on waterproofing a rocket.

I had one of mine land in a creek. It was a PML Callisto. The only part that wasn't water proof was the motor tube but it was fine.

If you get a PML kit with the plastic quantum tubing and replace the MMT with a fiberglass tube you should be golden. Use Hobbyline RMS motors. The air space between the fins and CRs acts as flotation and if you seal the nose cone so it will float too, you should be able to do water landing all day. The only problem you might have is the wet parachute and shock cords.

digitalastro
20th March 2010, 05:11 AM
I am amazed that nobody has pointed out that you can also fly during the winter!

When I was younger, my family had a house on a lake. Beyond the lake, were woods, and there were very few areas cleared of trees. I made many sacrifices to the rocket eating trees during the summertime trying to fly out of the small clearings that were available. When winter rolled around, and the lake froze over, I had a 2 mile wide, by 5 mile long treeless launch area! I would prep my rockets in the garage and load up the snowmobile with launch supplies. The snowmobile battery supplied the power for launching, and it also doubled as a rocket recovery vehicle. There were many parawad recoveries, because the plastic parachute froze and wouldn't open. But, a thick cover of snow made for soft landings.
One lesson I learned early on was to wait until there was a cover of snow on the ice. The bare ice surface is very hard, and not friendly to rocket landings. I can still remember that unique twang the ice would make as a rocket would come in ballistic and hit the ice.

MarkII
20th March 2010, 05:32 AM
I am amazed that nobody has pointed out that you can also fly during the winter! Of course you can, but I don't think that is an answer to the OP's real question. Otherwise, it's a good point, and one that is available to some of us. It really helps to have an ATV or a snowmobile available, though, for help in hauling everything out to the middle of the lake and for recoveries. And to find a day when there isn't a howling wind blowing across the ice.

Your description of the launch site quality of your youth sounds like where I live. Add mountains and you have the complete picture.

Snow-covered ice can often be slushy underneath, though, and not really firm and supportive.

Mark K.

brywisco
20th March 2010, 02:32 PM
Wow, I am overwhelmed at the quantity and quality of the responses.
You have given me alot to research and consider which is what I find fun about all of my hobbies.

It is funny that digitalastro pointed out winter launching. I live on lake Winnebago in Wisconsin and it freezes nicely during winter. It is also large...10 miles X 30 miles which should be enough room don't ya think?
I like the saucer made from fanfold foam. I have scratch-built RC planes from that stuff.

My son will have to be consulted here. He may have his heart set on a good old traditional rocket with a recovery chute and everything.

Again, thanks for helping me along here. The lake is thawing as I type....

Pantherjon
20th March 2010, 05:11 PM
You might want to contact the guys in Lakeshore Area Rocketry Society in Manitowoc WI. IIRC they do a launch from the pier every year where all rockets land in Lake Michigan. I'm sure they can give you lots of tips on waterproofing a rocket.
<snip>

They don't do anything to 'waterproof' the rockets..They have a Coast Guard boat in the vicinity of the 'splash down' zone and are able to have the rocket out of the water in under a minute..Now that I think about it tho, from conversations with Blackjack(he has been up there a couple times to help prep the team rockets) the rockets are all fiberglass using composite motors IIRC..

ScrapDaddy
21st March 2010, 12:51 AM
I am not really sure about this idea but say you explect the rocket to go 1200feet then attatch 1400ft of fishing line to the rocket and a fishing pole and reel in after deploy ment. I am not sure if this is against the NAR code but I would check:)

luke strawwalker
21st March 2010, 01:04 AM
Three words:

Estes' "The Dude"... :D OL JR :)

rcktnut
21st March 2010, 01:55 AM
Three words:

Estes' "The Dude"... :D OL JR :)

An excellent choice for water landings!! I am a Lakeshore Area Rocketry Society (LARS) member, we do not launch our rockets into Lake Michigan, but several LARS members have Rockets for Schools teams that do. It is Rockets for Schools that launch their rockets into the lake.

The demonstration models, the ones that can be handled by spectators etc. are made of fiberglass. The ones that actually fly into the lake are specially made kits by LOC, and are cardboard body tubes/plywood fins. Other than exterior paint nothing is done to waterproof them.

They are rapidly recoverd by boats, Coast Gaurd etc., and the teams will allow them to dry off awhile before putting them back together. In 13 years never seen one come apart due to water damage.

As far as floatation, the air space between the aft and forward centering rings in the booster section is sufficient to keep them afloat. No foam needed.

brywisco, if you are intrested in a place to launch, We, LARS have a field in Silica we launch out of, about 25 miles from you. If interested PM me.

Neutron95
21st March 2010, 07:25 PM
DART San Diego flies on an island, and every launch, we usually have a rocket or two land in the water, and we usually recover them with a kayak, and the rockets usually survive.

TheAviator
22nd March 2010, 05:29 AM
I was thinking: if you have experience with composites, get some lightweight fiberglass (.6-1.5 oz/yd^2) and use a tube coupler as a mandrel to roll your own tube. Use a plastic Estes nosecone and you are golden. One or at most two wraps of fiberglass should be plenty to stand up to model rocket stresses. Seal the fins well or use waferglass for them and then the motor and recovery system are your only worries.

ScrapDaddy
23rd March 2010, 05:38 AM
If you have some extra cash, a madcow ALL fiberglass honest John would be a great investment as it is all fiberglass and is waterproof, the problem is getting it to float..... It is 230grams w/o motor..........

brywisco
23rd March 2010, 08:20 PM
Wow those madcow rockets look really nice but are a bit much for where I am in this endeavor. I think my best bet is to buy an estes starter set with the plastic tail and nose and try to seal up the airframe tube the best I can.

I will also look at the saucer idea though that would take more effort to build initially.

The EGE
23rd March 2010, 10:52 PM
I have an Estes Jinx. It's unfortunately OOP (out of production), but it's an all-plastic 13mm rocket. With a kevlar shock cord and one of my nylon streamers, it is completely waterproof.

RimfireJim
23rd March 2010, 11:18 PM
DART San Diego flies on an island, and every launch, we usually have a rocket or two land in the water, and we usually recover them with a kayak, and the rockets usually survive.
Been there, done that - literally! Certainly not the best thing for the airframe, and salt water to boot. Worst thing is the swelling of the paper motor casing.

Micromeister
25th March 2010, 02:06 PM
Been there a couple times myself. several rivers, ponds and lake Anne LOL! Not good for standard build Cardboard & wood models. but most have servived if gotten out quickly and the spent motor casing removed before they swell.

To build a model specifically for water recovery wouldn't be all that hard, One of the Maryland funny meet events was floatation duration several years ago. Most folks used some sort of Plastic drink bottle as the fuselage to float the model with the motor mount above the waterline, as long as the fins are will sealed and painted some time in the water really doesn't hurt them, or sheet styrene could be used but that's a bit heavier;)

GrossApproximator
28th March 2010, 02:39 AM
I wonder if one of Art Applewhite's rockets would work. It looks like some of the designs (or some variant of the designs) use aerobrake recovery and, with perhaps a little extra balast in the nose, could be stable in the water. A good coating of primer, paint, and clearcoat could be waterproof (and if that fails, polyurethane coating).

MarkII
28th March 2010, 02:49 AM
I wonder if one of Art Applewhite's rockets would work. It looks like some of the designs (or some variant of the designs) use aerobrake recovery and, with perhaps a little extra balast in the nose, could be stable in the water. A good coating of primer, paint, and clearcoat could be waterproof (and if that fails, polyurethane coating).Yeah.... I kind of like that idea (http://www.rocketryforum.com/showpost.php?p=85158&postcount=17).

Mark K.

GrossApproximator
28th March 2010, 03:10 AM
Yeah.... I kind of like that idea (http://www.rocketryforum.com/showpost.php?p=85158&postcount=17).

Mark K.

:roll: Sorry. I didn't see that.

MarkII
28th March 2010, 03:13 AM
:roll: Sorry. I didn't see that.No, no - your post was good! It presented a more detailed explanation of the same idea that I had. Great minds think alike, you know. :D

Mark K.

ScrapDaddy
28th March 2010, 03:14 AM
:roll: Sorry. I didn't see that.
you just had a scrapdaddy moment :)

MarkII
28th March 2010, 03:17 AM
you just had a scrapdaddy moment :)Be thankful that it was only for a moment. For its namesake, on the other hand.... :rolleyes:

Mark K.