SkySailer Build. 3 Stage E - D rocket

[Orion14ed]

Orion here with a brand new build. I have been thinking about this design for some time, and finally got around to making it. The rocket is called SkySailer, and has a projected apogee of 3,400 ft. This is with 3 E-9 motors. For the first flight, I plan on using a combination of Ds and Es to increase the chance of getting her back. This is what it looks like.


Each stage is connected by a coupler, and the motor mount will be modified to help increase the chance of proper staging. Due to the projected altitude, it will use a streamer recovery rather than a parachute. If I did a parachute, I fear there would be no chance of me getting the final stage back. I will also find a way to cram a streamer into each stage, or on the outside of each stage, to find them more easily. The fins will be made of 3.32" balsa, and 4 will be on each stage. I have all the parts picked out, and am going to be purchasing them soon.

And I also have a question, I plan on purchasing the Estes Fin aligner to help build my smaller rockets. Is this a good idea?

[aditat2]

I have never used one. I have always just used a paper pattern ( like the one in the old Estes or Centauri publications). Always seem to turn out all-right. Just take your time when putting them on.

[JPVegh]

It's a cool design, multistage is a alot of fun and a real crowd pleaser when all works as it should. Everyone should build atleast one in their rocketry career. One thing to consider when staging is that the spent stages should tumble back to earth and not come in ballistic, you don't want to put a dent in someones car or head.

I have an Estes fin jig and it does work pretty well. Over the years I've managed to lose the motor mount pieces and had to make new ones. It's been a while since I've actually used it, I mostly eyeball my fin alignment now a days. As I and my eyes get older I may have to go back to using the jig. Paper patterns work well for finding correct spacing and they don't cost anything but a sheet of paper.

[StefanJ]

Following up on what Jeff said:

Consider making the booster fins trapezoidal rather than swept. Ideally, you want a booster stage whose CP and CG (with a spent motor) are together. This encourages a tumble rather than a ballistic trajectory.

[dwmzmm]

With that combination of engines, the chances of upper stage not being visible after burnout is pretty high. I launched a two staged, four engine cluster in each stage model (24 mm core and three 18 mm outboards) back in 2005 with an Astrocam as the payload and lost the model after burnout because it was so high we couldn't see it anymore, even though we heard four distinct pops of the ejection charges. The model was painted with high visibility colors and the parachute was a 20" nylon bright yellow. It was partially cloudy with blue sky. As suggested here, the fins of the booster stages were trapezoid. All four boosters were recovered close to the launch pad.

[Rocketbuilder]

I assume you meant E12's, since there aren't any E9 booster motors. Even with the E12's, I think you're close to the upper limit of the maximum liftoff weight. Just be sure to use a fairly long rod, and you should be fine.
Also, unless it's for looks, I would suggest making the stages a little shorter so the motors are closer together and more likely to stage properly.
Good luck! Should be a cool (and expensive ) flight!

[aditat2]

To get back to your question about fin alignment jigs - a useful little tool that you can make yourself, and very cheaply I might add, is to get a length of outside corner moulding at your local hdwr. store. You know the stuff that looks like angle iron. Place it on your trusty table saw and cut a slot in the point of the angle equal to the thickness of your fin stock. All you have to do is line it up to your fin lines, secure in place with a couple of rubber bands and glue your fin in place - being careful not to glue your guide to the bt. I haven't used this trick yet, but I plan on trying it soon.

[[POW]Eagle159]

I was thinking about something like this.... Just with smaller engines and a larger rocket! Low slow 3 stager with gap staging and a clustered first stage... Still designing though.

[Orion14ed]

That would be really cool. The launch would be awesome. I built this one for performance, rather than looks though. My next few builds will be for looks :3

[JimZNJ]

I like your ambitious projects. Having fun is what the hobby is all about.

I go through phases where high altitude is my goal. One real limiting factor on flying small rockets very high is being able to see them. I like to fly very reflective silver mylar streamers on the ones I send way way up there.

Last year for one of our local club launches I decided it would be fun to fly a scratch built two stage D12 to E9 minimum diameter rocket. To keep it really simple I designed it to be stable flying the motors CHAD staged. This way I didn't have to worry about tracking the booster too. The first flight on a C11-0 to C11-7 was so hard to visually track that I've never flown it on a more ambitious combination yet. One of these days though the conditions will be just right and I'll try it E12-0 to E9-8.

Good luck on your project.

Jim Z

[Orion14ed]

Thanks! I would say I am a dreamer, and I want to accomplish what I can while I can. I have tons of more designs that are more about testing concepts and experimenting with fins in the future. I just want to be able to say I have a 3 stage rocket in my collection. My next few i have planned I mess around with tubular fins, and strange fin designs.

EDIT: Cutting out some fins with my pa. 2nd stage fins are finished, and sanded. Only 8 more to go.... >.<

[Orion14ed]

Bump! Finished the fins. A total of 12, looking great!

[Rocketbuilder]

A total of 12...

That's the one thing I don't like about making three-stage rockets-- too many fins.
Then again, this is coming from someone who build a single-stage rocket with 19 fins...

[Orion14ed]

That seems... A bit up there lol.

[Orion14ed]

Ordered parts for SkySailer, along with 3 E12-0s. Should be here on the 1st.

[Orion14ed]

Got the parts! It looks simple enough, cant wait to start to build! May take me a while, busy for the next few days. Here are some pics I snapped with my horrible camera >.<

[awseiger]

ohhhh boy goodies!

I can't wait to see this one completed. The moment I heard about E12-0's I wanted to see a multi-stager built off of them.

[Orion14ed]

This should be great fun! I had to mod the design a bit to make the build slightly easier. The first stage body tube is only 3.5", one inch is for the coupler (2 inchs) to be inserted to. The coupler when inserted hits the centering ring that is placed 1inch from the foward end of the mount. This will alow for the motor to be very close to the 2nd stage, encouraging safe staging. (3 1/2 inchs. Motor hang is about 1/2 inch, and the forward ring is 1 inch in, allowing it to fit in such a small tube, considering 1.5 inchs is not inside of the tube.) The 2nd stage has the body tube at 5 inchs. (due to the fact it must now be enclosed) An inch at the bottom will let the 2nd half of the coupler attach, while the motor hook is about 1 inch, letting the hook pass through the coupler, so that is directly next to the 1st stage motor. Then, the first cent ring is places 2" into the 2nd body tube. Then like the 1st stage, the 2nd ring is placed 1 inch from the forward end of the tube. The coupler then slides in against the ring. This is one inch of space for the 2nd stage coupler, with the hook in this space, and then one inch of space forward for the 2nd stage coupler. (I may not be explaining this well) The 3rd stage will be much more simple. 1 inch of room for the coupler (again, with the hook ending inside of this coupler), and the 1st cent ring 1 inch back. I drew a 1:1 scale of it. It seems to work just fine... (My rule of thumb with this seems to be that the coupler is placed at the forward cent ring. This lets 1inch of motor mount go into the coupler. The length of a hook from the motor mount is about 1". This 1" is then placed so that it is to, inside the coupler. This lets the motor mount and next engine be close for proper staging. If I do have issues, or a mistake, I have an extra 18" of body tube to work with. I feel pretty good with this design. (and btw, the couplers fit a little too tight. Sand them down?)

[awseiger]

This should be great fun! I had to mod the design a bit to make the build slightly easier. The first stage body tube is only 3.5", one inch is for the coupler (2 inchs) to be inserted to. The coupler when inserted hits the centering ring that is placed 1inch from the foward end of the mount. This will alow for the motor to be very close to the 2nd stage, encouraging safe staging. (3 1/2 inchs. Motor hang is about 1/2 inch, and the forward ring is 1 inch in, allowing it to fit in such a small tube, considering 1.5 inchs is not inside of the tube.) The 2nd stage has the body tube at 5 inchs. (due to the fact it must now be enclosed) An inch at the bottom will let the 2nd half of the coupler attach, while the motor hook is about 1 inch, letting the hook pass through the coupler, so that is directly next to the 1st stage motor. Then, the first cent ring is places 2" into the 2nd body tube. Then like the 1st stage, the 2nd ring is placed 1 inch from the forward end of the tube. The coupler then slides in against the ring. This is one inch of space for the 2nd stage coupler, with the hook in this space, and then one inch of space forward for the 2nd stage coupler. (I may not be explaining this well) The 3rd stage will be much more simple. 1 inch of room for the coupler (again, with the hook ending inside of this coupler), and the 1st cent ring 1 inch back. I drew a 1:1 scale of it. It seems to work just fine... (My rule of thumb with this seems to be that the coupler is placed at the forward cent ring. This lets 1inch of motor mount go into the coupler. The length of a hook from the motor mount is about 1". This 1" is then placed so that it is to, inside the coupler. This lets the motor mount and next engine be close for proper staging. If I do have issues, or a mistake, I have an extra 18" of body tube to work with. I feel pretty good with this design. (and btw, the couplers fit a little too tight. Sand them down?)

Pictures! Pictures! But I get what you're saying.

Coat your couplers in CA, then sand them down. You'll have less fuzzies that way.

Also, when using hooks and staging, I'd personally use the "basic" hooks, with only a little bit of metal at the end, instead of the "thumb safe" hooks that estes and quest use. This allows the motors to sit closer.

[hornet driver]

A very cool project--get a lot of pics out of the build----a silver mylar streamer is a great idea but i might add one thing--cut up some mylar strips of varing sizes and stuff them in there too. The result is a larger target in the sky to see! once you find it you can pick out the faster falling rocket---maybe---worked for me in the past-- also a low sun---morning or late afternoon helps!

[Orion14ed]

Will be doing, having my grandfather over in a few days. He started me in it, and this is sorta my last build with him helping (passing it down to say?). The engine hooks will be trimmed down to get that little notch off, this measures them about an inch from the body tube (exactly what I need). I am sure I have made some few miscalculations, but they would be very small, and nothing that cant be fixed with my supplies atm. I was thinking of adding some cut up aluminium foil in there, to give it that extra help it needs. (I may have some very reflective tape around here..) Dont worry, pictures will be taken. Cant wait!

[pick1e]

Looks cool! I too love staged rockets. I just flew my Comanche-3 with all three stages for the first time last Saturday at NARAM. It went plenty high on a C11/B6/A8-5 and got some accolade. I think if I loaded it up with D12/C6/C6 I would never see it again. You might be able to do that if you flew in the desert I will be building a BT-55 upscale so it's easier to see at altitude- it will be very similar to yours.

I modified my Comanche-3 from the original design in that I lengthened the boosters 3/8" to allow for motor retainer clips and gap staging. Unfortunately the added length made the second stage stable so I had to rebuild it with the fins moved forward 3/4 inch which seemed to help. Otherwise I ended up with this:



And on not so soft ground, this:



I would highly recommend you do TTW fins. I did this after the fins broke off the first build of the second stage upon hitting the ground (that stage is on its 3rd incarnation now). I haven't had a problem with that one since. Unfortunately the first booster stage is minimum diameter, so I couldn't do TTW fins and thus had a fin break off the first time I used it. That's another reason I want to do the upscale, so I can get TTW fins on every stage. The spent 24mm casing is pretty heavy and it hits the ground quite hard.

Another thing I did was fly a series of every motor configuration, each time increasing by A impulse. Started with B6/A3, then B6/B6, then C6/A3, C6/B6, and finally C11/B6/A8. This gave me a really good feel for how the motor weight distribution affected the flight. Make sure with that load of motors that you'll be getting 40ft/s off the rod and verify with the recommended max liftoff weight for the boosters.

Another big thing is make sure you sand the couplers in some sort of fashion where you keep the sandpaper parallel to the center axis of the tube, for example with the sandpaper wrapped around a spare coupler. Otherwise you will round over the coupler. This makes for some play in the connection, which isn't a huge deal for a two stage rocket, but with three stages any play in the first connection is amplified to the second connection so that your first booster can flop around like a universal joint.

Hope this helps, looking forward to seeing your progress! I see you're from Michigan, where do you fly?

[Orion14ed]

That looks like a nice rocket... After you modded it and all. I would like to have been able to have a lower level E engine, but the issue is there are no -0 delay engines at any store around me. Then I have to order them... And it costs a good bit more. It was cheaper to go and buy a set of E12-0 then a set of E12s and E9s. (If they even have those anymore >.<) If more people made staged rockets then we wouldn't have this issue lol. This is my first real attempt at a staged rocket, and after this I plan on having one more build then to go to HPR and try to get my jr cert. (HPR will be a kit... I am not messing around with that stuff xD) As for through the wall, I did consider it, but I think that with a strong enough glue or epoxy, I believe they should be fine. Adding a coat of epoxy on the outsides may help....

And as to my location... its a secret.... shhhhh
But I am looking at clubs, and I think I have found one that isnt too far from here. Should be joining a club in the next few months.

[blackbrandt]

Yes, they have E9's at Hobby Lobby, if that is what you're asking about.

[Orion14ed]

I have a sad. I went for a few weeks looking for them, found nothing. I guess that I could get one of those fancy 40% coupons and buy me a set with a D motor pack. In fact, that is what I will do. I dont see me getting completely finished for a few weeks. (You know, paint can take a while >.<)

[blackbrandt]

I have a sad.

What do you mean? Is this a typo?

[blackbrandt]

Ever thought about payloadbay.com's fin alignment jigs? You just print them off, and then you are set.

[pick1e]

but I think that with a strong enough glue or epoxy, I believe they should be fine. Adding a coat of epoxy on the outsides may help....

That's what I thought I put on some huge epoxy fillets but what happened is it just peeled away the top layer of the body tube. It wasn't the glue joint that failed.

And as to my location... its a secret.... shhhhh

I'm just saying- if you are in the Tri-Cities area, PM me. I know there are a handful of us around here and we really should start up a club.

PS That booster fell from an estimated 75ft according to my sim with a spent D motor casing.

[Orion14ed]

@Blackbrant I have a fin alignment jig, its pretty nice, and will let me mark exactly where I need my fins, its simple, and can be reused.

[Orion14ed]

Pictures! After a long day, I have a few concerns... Currently the fins are on the body tubes... but we made a HUGE mistake and painted before we glued. The glue is setting, and the fin alignment looks about okay, but the issue is at high speeds I am concerned about the fins getting blown off. The glue is about is labeled "very-strong" and is used for permanent adhesive. (Not that great I can imagine.) So my plan is to cut out the extra glue along the fins that has piled up. Once this is done, I will then epoxy it, hopefully adding more strength. Will it work? I dont feel like re cutting and re-doing everything. ( You can see the glue on the side of the fins in the images, replace that with epoxy fillets?) The motor mounts are not in, and my messurements I have found to be correct. Each part will fit nicely into the next. I just have to get it all together. My concern is the fins. Should I scrap it (really dont want to), or find a way to add epoxy around it to glue it to the actual body? Advise would be great. If I must scrap it, I have the resources... (Cant upload images now... I must go, and they are in HD so I need to edit them, dont have time...) https://www.dropbox.com/s/w8hpt8qcyfx6vd2/new%20028.JPG That may work. May not :\