Estes Big Daddy - stock or modifications?

Hi Folks,

First post, here! I'm working with my daughter's introduction to rocketry, and we're having a great time with it. She gave me a Big Daddy by Estes as a gift, and I'm excited to fly it!

I haven't started the build, yet, and started with research on it - searching for it here on these forums and elsewhere. I have seen mentions of it becoming a "lawn dart," as well as arcing when under-powered. So, I have a few questions if anyone is up for answers!

-I plan to build it stock, but one person noted that even too much paint might impact its flight dynamics. Should I be adding weight to the nosecone? I plan to fly it with a D12-3, as I was also gifted a dozen of those.

-Suggestions for the rod diameter and length?

-I have a nylon parachute, but it's larger than the included 24" plastic one at 30". Will that be an issue to use? Too heavy? Cut a hole in it?

Any advice at all regarding a straightforward build to the newcomers would be great - thank you!

-Chris

Mod the nosecone... get rid of the ramp that vents the ejection charge... prevent yourself from having a Big Lawndart Daddy.

If built stock for recommended motors no additional nose weight is needed. If you build for bigger motors then nose weight may be necessary. To often it seems many builders are adding nose weight just because th ey think its needed. As for the nose cone mod that really is a good idea, Big Daddy's are well known for failing to eject the nose cone fully.

Welcome to the forum!

A super helpful tool for building and designing rockets is OpenRocket. (free)

Here's a link to a compiled easy installer Neil_w's Openrocket installer

It's really easy to learn (youtube tutorials), and you can always ask around here in the Electronics and Software section of the forum. (where 5 people will chime in with 7 different answers, at least 3 of which will directly contradict )

Good choice. I built mine stock in 2006 as my return to flight BAR model. It came in at just about an ounce over the catalog weight, .8 or .9 as I recall. It is a great flyer on D12's and E12's, E9's not so much. Sometimes you get a decently straight boost with that one and sometimes you get a horizontal cruise missile.




Cutting off the sloped part of the nose cone shoulder is a very common mod, maybe if I'd joined the forum before I built mine I would have done it. :blush: My solution was to sand the shoulder to a very loose fit and check and re-sand after every flight as needed. As far as the parachute goes mine has drifted quite far on the stock size; I'd be afraid of losing it on a 30 inch. Rather than cut nylon parachute I would reef the shroudlines to prevent the canopy from opening all the way. Tape the lines together somewhere between a third or halfway up from the ends. I would also recommend getting a nomex parachute protector for this model since you don't have a lot of room for wadding let alone shock cord and recovery device.
One issue I don't believe has been corrected since I built mine is that fin slots in the airframe are cut a bit longer than the tabs on the fins. Not to bad, maybe 3/16 or 1/4 inch. I installed the fins with tabs butting against the aft end of the slot and used some pieces of index card glued to the inside of the airframe at the forward end to cover gaps. The normal glue fillets covered any sins on the outside. Hope this helps.

[edit] The TRFers love this rocket and some have done some insane, or insanely great, modifications. You be the judge. Click on the Advanced Search, type big daddy, click the drop-down box and select Search Titles Only. Then click Search Now and enjoy.

[another edit] Welcome to the forum !


Almost forgot, it does benefit from using a longer launch rod; 4 feet is good.

a nice 'mod' used for launching a big daddy, 5' - 6' of 1/4" stainless steel rod
Rex

the fin slots are holdovers from the BD's patriot days.
Rex

I built mine 100% stock and it flies great on D12-3s and Aerotech 24/40 reloads (fun as heck on an F24!). My kit was before they changed the motor mount length to fit E motors, but I'm sure the new one is fun on 24/60s. E9s are a bad idea unless built light on a windless day (I've seen them on other BDs). It's a light kit, so a 24" chute will drift a ton. Go with 18", reef the lines, or invest in a Chute Release.

Never had the partial nose cone deployment issue, but I've heard of it. I've since:
1) Sealed off the hole in the bottom of the nose cone (reduces volume that must be pressurized)
2) Kept the nose cone fit pretty loose. If you do have to tighten it, add tape only to the top end of the NC shoulder - that way the "tight" part of the cone is guaranteed to be out before the sloped shoulder can be an issue.

K'Tesh said:

Mod the nosecone... get rid of the ramp that vents the ejection charge... prevent yourself from having a Big Lawndart Daddy.

Click to expand...

Thank you, this advice recurs below, too! I'm just not sure HOW that process would go - getting rid of it would leave a shorter neck on the NC, and also a wide-open nosecone. Is that what I want? Is this action to let the nosecone pop out during ejection a little easier?

Rex R said:

a nice 'mod' used for launching a big daddy, 5' - 6' of 1/4" stainless steel rod
Rex

Click to expand...

Thank you! So a longer, stiff rod works well with it?

Oberon said:

I built mine 100% stock and it flies great on D12-3s and Aerotech 24/40 reloads (fun as heck on an F24!). My kit was before they changed the motor mount length to fit E motors, but I'm sure the new one is fun on 24/60s. E9s are a bad idea unless built light on a windless day (I've seen them on other BDs). It's a light kit, so a 24" chute will drift a ton. Go with 18", reef the lines, or invest in a Chute Release.

Never had the partial nose cone deployment issue, but I've heard of it. I've since:
1) Sealed off the hole in the bottom of the nose cone (reduces volume that must be pressurized)
.

Click to expand...

Thanks! You're suggesting I not cut off the NC neck at the ramp, and just seal the hole to get the back pressure for deployment? I'll be using D12s...

Nytrunner said:

Welcome to the forum!

A super helpful tool for building and designing rockets is OpenRocket. (free)

Here's a link to a compiled easy installer Neil_w's Openrocket installer

It's really easy to learn (youtube tutorials), and you can always ask around here in the Electronics and Software section of the forum. (where 5 people will chime in with 7 different answers, at least 3 of which will directly contradict )

Click to expand...

Downloaded! Thank you!

I haven't build mine yet, but I plan to place a disk at the bottom of the nosecone to act as a piston & prevent the lawn dart syndrome.

T-Rex said:

I haven't build mine yet, but I plan to place a disk at the bottom of the nosecone to act as a piston & prevent the lawn dart syndrome.

Click to expand...

So by "lawn dart syndrome" we're talking about the failure of the nose cone to pop off and the chute deploy? I have sheet styrene - is that something one might use? Any images around of a similar modification? Thanks!

cappy227 said:

So by "lawn dart syndrome" we're talking about the failure of the nose cone to pop off and the chute deploy? I have sheet styrene - is that something one might use? Any images around of a similar modification? Thanks!

Click to expand...

Yes, the nose not popping off due to depressurization when the 'ramp' section is exposed resulting in 'nose in the dirt like a lawn dart' landing .
Sheet sytrene might work if thick enough to not bend out of the way. My plan was 1/8 plywood. Really anything that you can attach to the bottom of the nose should work. Just fit it to the body tube like the nose cone shoulder so it slides out, but 'seals'.

If you go the 'cut it off' route, you can glue a disk up in the nose cone that will minimize the volume that needs to pressurize (an gives a place to attach the shock cord).

longer stiffer launch guide (rail or rod) gives a higher speed off the pad and reduces weathercocking (the tendency to fly into the wind). you will be wanting something fairly stiff to make a disk out of, 1/16" aircraft ply should suffice.
Rex

bunch of info and links here; https://www.rocketryforum.com/showthread.php?130943-Big-Daddy-nosecone-Mod-question
Rex

Rex R said:

bunch of info and links here; https://www.rocketryforum.com/showthread.php?130943-Big-Daddy-nosecone-Mod-question
Rex

Click to expand...

+1 Check out that thread for the best ways to mod the nosecone. The only other "mod" I would suggest is looking into Aerotech 24 mm composite motors. The E20, E30, F32 and F44 single use motors are the gateway drug to high power rocketry! https://www.buyrocketmotors.com/24-mm/

Lots of great advice here but from my experience, if you build a Big Daddy per directions and paint it any way you like, you will have a good performing rocket on a D12-3

If you deviate from the directions (my favorite thing to do) then you need to look into getting the model back into sync with CG and CP.
good luck and keep up posted

Just add the "Seal disk" at the bottom of the cone as suggested above. I used 1/8" basswood for mine. It also helps with the balance as the weight is on the "good" side of the stock CG. I've had 7-8 perfect flights on mine so far. D12-3 is the minimum I'd fly on. The E12-6 is a great motor.

I chopped off the shoulder just above the "ramp" and put in a bulkplate above the step. Then add an eye-bolt to the plate. Gives more interior room for laundry and adds a little weight up top. Regular flyer on AT E20Ws single use and still flys on the D12-3 in my front yard. I eventually upgraded shock chord to kevlar, a nylon chute (thin mil works best), and use a Nomex blanket.

My next one may be glassed with a nose cone bay.

Any rocket will arc badly or go cruise missile if under powered.

I built my first one completely stock and flew it over twenty times in the stock configuration using D12 3's 5' and E9 4's. Even used an E9 6 for some excitement in good weather. Had to replace the stock rubber shock cord after flight eight because of the low mounting point eventually suffers heat damage, even with dog barf. Replaced it with high quality underwear elastic. The Big Daddy is a great rocket that will teach you many things about how to fly model rockets. The stock chute is fine in calm or low wind situations, reef or replace with smaller one if some wind is present. If wind is present it likes to weather cock, so if that is happening what do you do? Bigger motor? Longer or shorter delay? Check nose cone tightness? Make the wrong choice in wind and you just increased your likely hood of the dreaded lawn dart. The Big Daddy is short and fat so if you get him going nose down over apogee a lot of pressure builds up on that cone. Sometimes Estes motors have shot gun ejection charges, sometimes they are weak; nose down with weak charge is bad combo. The stock internal nose cone shape can be a contributing factor. So to can be too much wadding, a tight parachute pack, a tight nose cone from dirt, soot, temperature or humidity.

So after twenty some flights I eventually crashed my Big Daddy, lawn dart, core sample. It was due to the only time in 2,000 BP motors I have flown over the years where the ejection charge was missing, leaving the top clay cap completely in tact. Repaired and flew many times again with a new paint job. Then built another one with aftermarket Der Grosse Vatti decals. Flew it many times. Crashed it bad in max wind on an E9 4 because you will eventually get complacent. Cut off the fin can and inserted a coupler from a salvaged bit of body tube, stuck the old original on top and tried to fly two stage on a D12-0 D12-5 combo. That never worked real well and resulted in some long recovery walks and even more damage. Now it sets on the shelf of honor.

Long stiff rod always good! Paper fins good. Good flying conditions - good. Heavy mods and flying with wicked motors - crazy good if you know what you are doing.

cappy227 said:

So by "lawn dart syndrome" we're talking about the failure of the nose cone to pop off and the chute deploy? I have sheet styrene - is that something one might use? Any images around of a similar modification? Thanks!

Click to expand...

Personally, I don't have a Big Daddy built. I'm mostly interested in the original livery (I'm not the best with fading paint jobs), and the last one that came up on eBay sold for more than I had to offer.




I've thought about it a lot, and one idea I had was to cut the ramp away, stick in a bulkhead, and then fill the hole with sheet styrene. I'd get a larger recovery bay that way (yet still smaller than having that hole in the bottom of the nosecone to add volume needed to be pressurized), and a secure mounting location in the deal. A previous idea I had was to glue some foam to the ramp, and shape that to fit inside the body tube, but that wouldn't decrease the overall volume by much.

My .ork file for the stock BD can be found here.

Wow you guys are all great - thank you! I'll combine most above advice. I'll saw off the ramp and epoxy in a disk with an eyelet, go with a smaller chute and get a 5' stiff rod for Launch#1. This will take a while to get together having to order some stuff, but will update when it's altogether!

FINALLY - launch success! Thanks so much to everyone and their suggestions! The only thing that could have gone better was the Top Flight chute protector - the D-12-3 burned a hole straight through it.
[video]https://youtu.be/tYv_RPMR0XQ[/video]

:clap:

I flew my Big Daddy Saturday on a D12-5. Thin-mil nylon chute, DinoChutes chute protector and a JLCR. It popped just a second or so before the JLCR did it's thing. The extra weight of the JLCR caused it to arc more than usual and it drifted to the edge of my property and landed in a tree. Shotgun/machete recovery and all is well. It was mostly a test flight for the JLCR.

-Hijack in progress-
I had some help getting it to the pad.



She couldn't stand it that she couldn't help with the recovery. LOL.

Nice, Mickey! I'm sure you saw my little elf come running in at the end, too So I looked up a DinoChutes protector. Recc? I am stunned the chute protector I used had a hole burned through it on the one launch? Is that normal?

MikeyDSlagle said:

:clap:

I flew my Big Daddy Saturday on a D12-5. Thin-mil nylon chute, DinoChutes chute protector and a JLCR. It popped just a second or so before the JLCR did it's thing. The extra weight of the JLCR caused it to arc more than usual and it drifted to the edge of my property and landed in a tree. Shotgun/machete recovery and all is well. It was mostly a test flight for the JLCR.

-Hijack in progress-
I had some help getting it to the pad.

View attachment 345467

She couldn't stand it that she couldn't help with the recovery. LOL.

Click to expand...

Love the outfit!

cappy227 said:

Nice, Mickey! I'm sure you saw my little elf come running in at the end, too So I looked up a DinoChutes protector. Recc? I am stunned the chute protector I used had a hole burned through it on the one launch? Is that normal?

Click to expand...

Yep saw that. Like mine, couldn't wait for it to hit.

No, burn through after one flight is not normal. I have many flights with Topflight chute protectors with no burn through. I've flown Topflight, DinoChutes, and Recon (Wildman). I have one from MAC but haven't flown it yet. The Dino's are more flexible and seem thinner than the others but have held up fine. They are made with a ripstop looking fabric, so is MAC and Recon, but not as stiff as those two.
They did have free shipping for Memorial Day, not sure if that still going. Check the yard sale section for a few deals. Pat is easy to work with and fast shipping. They are geared mostly toward LPR/MPR. I've been going to try their deployment bags but haven't done so.

https://www.dinochutes.com/Parachute-protectors_c4.htm

Bat-mite said:

Love the outfit!

Click to expand...

She was apathetic in the matter. Lol

For future flights, as for "arcing over when underpowered" the solution is simple: don't underpower it. A few people have mentioned E9's but it is a bit underpowered for speed off the rail. It's also notorious for CATOs. I'd stay away from it and stick with E12 an D12.

For your second BD, which quite a few people end up building.

1. I didn't sweat the overlength fin slots on my two; the root edge of the fin beyond the tab covers it with just the thinest lines open on either side, the normal fillets seal those up, and you're good to go.

2. A 29 mm motor mount is a crazy popular mod. It's pretty easy if you don't make the tube much longer in the process. (Somewhat longer is easy enough. I went lots longer, but you don't have to.) That'll get you beyond E and into F and G motors, and you'll have to start a new thread in the Mid-power section.

Oh, and, congrats on the successful flight. May you have many more.