hello friends, i have bult my big dog. it comes with an d,e adapter. i installed the egine block. should i take a screwdriver and knock that out? in other words will i be screwed using f motors with it? i also have a estes motor retainer i could put on it. any ideas? i have put first coat os primer on her. shes a pretty bird.
big dog question
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I would take it out. I am not a big fan of the limiting that an engine block gives you.
JPVegh
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Yeah you'll be screwed using F motors in it. That thing is gonna disappear on an F motor.
Seriously though, the F32 is the same dimensions as the E9 so you should be good to go as built.
Seriously you'll lose it on an F.
Seriously though, the F32 is the same dimensions as the E9 so you should be good to go as built.
Seriously you'll lose it on an F.
i was reading through apogee's site. and they state there is no retainer to keep the e motors in. but it comes with an adapter. this rocket has me confused. i was planning on using e's on it. 3k feet is hard to see. im happy with half that and getting it back. will the darn e9 work in this bird? should i buy a 24mm retainer or just use the adapter? anybody with experience on this?
What is the downside of this rocket?
That's a smart question to ask. The big flaw (but fixable), is that the kit does not have a retention method to hold in 29mm motors, nor the 24mm adapter assembly.
Big Dog cloth parachute
To fix it, we recommend a motor retainer, such as the one from Aero Pack. That will hold the motor securely in place during flight without having to wrap tape around it to friction fit it into the tube.
The other thing we noticed is that the 24mm motor adapter can only be used with standard length motors that are 2.75 inches long (like the Estes D12, C11 or the Aerotech E15, E20, or E30). To use the longer 3.75 inch motors, like the Estes E9 or the Aerotech F32, you will have to completely replace it. If you already have a 24-to-29mm motor adapter in your rangebox, then you're probably all set anyway
replace what???
That's a smart question to ask. The big flaw (but fixable), is that the kit does not have a retention method to hold in 29mm motors, nor the 24mm adapter assembly.
Big Dog cloth parachute
To fix it, we recommend a motor retainer, such as the one from Aero Pack. That will hold the motor securely in place during flight without having to wrap tape around it to friction fit it into the tube.
The other thing we noticed is that the 24mm motor adapter can only be used with standard length motors that are 2.75 inches long (like the Estes D12, C11 or the Aerotech E15, E20, or E30). To use the longer 3.75 inch motors, like the Estes E9 or the Aerotech F32, you will have to completely replace it. If you already have a 24-to-29mm motor adapter in your rangebox, then you're probably all set anyway
replace what???
SacEsq
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I have one of these and I can comment on the following:
1. You will not lose it on a AT SU F motor. It flies great with that motor.
2. If you are using AT SU motors or a reloadable you should take out the block. While the SU motors fit just fine with the block (I know because I built mine with the block) you will not be able to use most reload casings. The only one I can use is the 29/60.
3. The block seems to be in place only if you use the D/E adapter and since I have no plans to use those I never built the adapter but did not realize I should have left out the block.
It is a fantastic rocket with arrow straight flight almost out of sight on the "F" SU motors I have put in there. It is one of our (me and my boys) favorite rockets in the collection. I recently bought the 29/60 case to start putting in reload and save a buck or two per launch.
Have fun.
1. You will not lose it on a AT SU F motor. It flies great with that motor.
2. If you are using AT SU motors or a reloadable you should take out the block. While the SU motors fit just fine with the block (I know because I built mine with the block) you will not be able to use most reload casings. The only one I can use is the 29/60.
3. The block seems to be in place only if you use the D/E adapter and since I have no plans to use those I never built the adapter but did not realize I should have left out the block.
It is a fantastic rocket with arrow straight flight almost out of sight on the "F" SU motors I have put in there. It is one of our (me and my boys) favorite rockets in the collection. I recently bought the 29/60 case to start putting in reload and save a buck or two per launch.
Have fun.
i measured the adapter block and the engine casing together they are 4.5 inches. i would assume you need the block because an e would go way to far in without being friction fitted
I have one of these and I can comment on the following:
1. You will not lose it on a AT SU F motor. It flies great with that motor.
2. If you are using AT SU motors or a reloadable you should take out the block. While the SU motors fit just fine with the block (I know because I built mine with the block) you will not be able to use most reload casings. The only one I can use is the 29/60.
3. The block seems to be in place only if you use the D/E adapter and since I have no plans to use those I never built the adapter but did not realize I should have left out the block.
It is a fantastic rocket with arrow straight flight almost out of sight on the "F" SU motors I have put in there. It is one of our (me and my boys) favorite rockets in the collection. I recently bought the 29/60 case to start putting in reload and save a buck or two per launch.
Have fun.
i built mine with the block because thats what the instructions says to do. i would like to fly it on an e for first flight or even a d just to see how high she goes. this rocket is light but built tough. but i would like to use an f later. so im guessing using the 29mm motor retainer wont do me any good unless i use AT SU f motor only?
I have one of these and I can comment on the following:
1. You will not lose it on a AT SU F motor. It flies great with that motor.
2. If you are using AT SU motors or a reloadable you should take out the block. While the SU motors fit just fine with the block (I know because I built mine with the block) you will not be able to use most reload casings. The only one I can use is the 29/60.
3. The block seems to be in place only if you use the D/E adapter and since I have no plans to use those I never built the adapter but did not realize I should have left out the block.
It is a fantastic rocket with arrow straight flight almost out of sight on the "F" SU motors I have put in there. It is one of our (me and my boys) favorite rockets in the collection. I recently bought the 29/60 case to start putting in reload and save a buck or two per launch.
Have fun.
Sac what motors do you use exactly?
SacEsq
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Yeah I built mine with the block because the instructions said to do so ... I did not realize it would limit the motors (reloadable) that I could use. If you use a 29/60 case or just want to use the SU motors having the block in there will be fine. It will also let you use the adapter so you can use the D/E motors you want as well.
The only motors I have used are F20-7W AT SU.
The only motors I have used are F20-7W AT SU.
i have a ten year old for fetching lol. may i ask what at 24 rms means? btw i will post some pics of my fleet when i have her done with my big daddy. i am also working on a clone of a super big bertha. but the balsa fins i think i will keep that as a hanging model and use 1/8 ply and start a new one.
how high does she go with that motor? how did you retain the motor?
SacEsq
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Motor retention is with an Estes screw on 29mm retainer. Like this one: https://www.estesrockets.com/rocket...ies/002950-pro-series-ii-29mm-motor-retainers
Not sure how high. Didn't SIM it nor did I have an altimeter. But it went almost out of sight
JPVegh
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Yeah I remember the days of having young ones to chase for me, that was nice.
RMS=Reloadable Motor System, AeroTech sells two reloadable motors in 24mm diameter cases, the 24/40 and the 24/60. Saves you a little bit of money per launch.
The Super Big Bertha is a real favorite of mine. In fact Big Bertha in any scale never fails to make me smile. She flies great as designed but the fins are a weak point. A through the wall plywood finned Bertha handles G power pretty well but when you strengthen the fins the stress of landing is transfered to the body, I've experienced some crimpping because of this. Extending the motor tube to act as a stuffer adds some strength to the airframe but I still had some minor crimpping just above the fins. If I ever build another one I will use the thick walled BT-80H.
gpoehlein
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I don't have the Big Dog, but I built the High Q, which is similar. I did not put the motor block in. Ipushed an Estes 29mm motor retainer on the HQ and it works great. I also made an adapter that works very well with the Estes retainer. My adapter is 4" BT-50 with two 24 to 29mm centering rings from BMS at the front and in the center. I installed a 24mm motor block inside at the front because it will only be used with BP motors. I made a retainer ring for the back from 1/4" wide strips of 110# cardstock (you could use strips if index cards if you wanted, or even strips of computer paper). Finally, I use an Estes CR-2055 cardboard centering ring to hold the 24mm motor in. E9 motors fit flush in the adapter and I use one of the Estes orange motor spacer when flying with D12 motors. I flew it once on an E9-4 and the flight was great!
Motor retention is with an Estes screw on 29mm retainer. Like this one: https://www.estesrockets.com/rocket...ies/002950-pro-series-ii-29mm-motor-retainers
Not sure how high. Didn't SIM it nor did I have an altimeter. But it went almost out of sight
i have some of those. i guess i will install one. can you use the RMS e powered with that installed?
that sounds great, but man i cant picture what you made to save my life. i wanted to be able to fly it with e9's and possibly the f series.
Motor retention is with an Estes screw on 29mm retainer. Like this one: https://www.estesrockets.com/rocket...ies/002950-pro-series-ii-29mm-motor-retainers
Not sure how high. Didn't SIM it nor did I have an altimeter. But it went almost out of sight
you still need the motor block with that retainer too dont you? it only seems to keep the motor from coming out not being pushed in. am i correct?
SacEsq
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No you do not need the motor block. The SU motors from AT have a lip on the end which prevents them from going up into the rocket upon thrust. The reloadable cases have the same "lip" which prevents the motor from going up into the rocket. The retainer keeps it from ejecting the motor instead of ejecting your NC and recovery system.
the re-loadable e powered motors
gpoehlein
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I posted a PDF file with plans for the adapter in this thread:
https://www.rocketryforum.com/showthread.php?36033-estes-29mm-motor-retainer&highlight=Retainer
As I noted in a followup post, don't bother with the adapter ring in the file - use a CR-2055 adapter ring instead - the outside diameter of the one in th file turnsout to be too small and the BT-55 centering ring fits better. And, yes, it will hold up for at least a few flights. If you want something more durable, you could trace it onto a piece of sheet brass from K&S.
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