Executioner x3

[SacEsq]

I am just about finished with my Estes Executioner build. As I have mentioned in previous posts I changed a few things. The first being a baffle and the second is the addition of a 3x24mm motor mount. All I have to do now is decide on a pain scheme which I am having some trouble with.

So ... what do you all think? Any problem with these three motors in there? :y:



Also ... think any nose weight is needed? One response I got on a previous post indicated that this kit was already over stable and did not need it with the addition of the 2 extra motors.

 

[astroimgur]

There absolutely must be a video when this is launched! :eyepop:

 

[Wayco]

The only problem I see is getting all three motors fired simultaneously. The copperhead that fits those small hobbyline reloads might give you some grief. We tried the new Estes pro igniters and they wouldn't light the E18's Sharon wanted to fly her Starburst 2X cluster on. The copperheads worked for her, but I was really sweating it. She put a lot of work into this discontinued LOC kit:

I painted my Executioner black with red fins and a spot of silver behind the decal so the "executioner" would show up. Went the other way with my MMT and did it in 29mm with the new Estes motor retainer:

 

[kelltym88]

One way to check for stability is to load all 3 motors and then hold the rocket at least 1 caliber forward of the CP. (I should say balance it, like on a finger). If it tilts back (motor end) add nose weight to level it out. BB's are really good for this.

 

[o1d_dude]

One of the easiest ways of adding ballast is to simply use a quick link or three to attach the shock cord to the nosecone.

Do locate the CG as described in the post above and then add quick links until it balances where you want it to. As a "general" rule on most rockets, the CP is just ahead of the fins. If you have sim data that definitively locates the CP, use that and add balance weight as needed to get the CG one body tube diameter (BT-80 = 2.6", etc.) forward of the CP.

 

[SacEsq]

The only problem I see is getting all three motors fired simultaneously. The copperhead that fits those small hobbyline reloads might give you some grief. We tried the new Estes pro igniters and they wouldn't light the E18's Sharon wanted to fly her Starburst 2X cluster on. The copperheads worked for her, but I was really sweating it. She put a lot of work into this discontinued LOC kit:

I painted my Executioner black with red fins and a spot of silver behind the decal so the "executioner" would show up. Went the other way with my MMT and did it in 29mm with the new Estes motor retainer:

I was thinking about the possibilty of simultaneous ignition. However, I do not use the copperheads but instead use the First Fire Jr. igniters and have had better luck. I too have noticed the new Estes igniters will not ignite the AT SU motors and sometimes not even the new Estes motors (weird). However, for the first flight I will most likey stick with 3 D12-5 motors.

BTW ... great paint on your Executioner.

 

[SacEsq]

One of the easiest ways of adding ballast is to simply use a quick link or three to attach the shock cord to the nosecone.

Do locate the CG as described in the post above and then add quick links until it balances where you want it to. As a "general" rule on most rockets, the CP is just ahead of the fins. If you have sim data that definitively locates the CP, use that and add balance weight as needed to get the CG one body tube diameter (BT-80 = 2.6", etc.) forward of the CP.

Thanks ... I believe someone gave me a link to a webpage with the specs for this (and many other kits) including CG/CP locations etc. I will check that out.

Also ... I plan on using epoxy and a small eybolt (and washers if needed for additional weight) in the NC and for attaching the shock cord to the NC.

Was bummed SARG launch was cancelled ... was gonna send this up first thing .... oh well next season

 

[El Cheapo]

When you do send it up, you may want to off set your ejection charges with two five second and one seven second.

 

[SacEsq]

When you do send it up, you may want to off set your ejection charges with two five second and one seven second.

Interesting ... why do you suggest that? Over pressure on ejection? Backup in case the 5 sec does not work?

 

[chadrog]

Interesting ... why do you suggest that? Over pressure on ejection? Backup in case the 5 sec does not work?

I think it was suggested more to prevent them all from popping at once, that would be a lot of boom.

 

[El Cheapo]

All of the above. In theory, I think its a decent idea and use it myself in three or four motor clusters. In reality none of them will fire at the same time but it can't hurt to utilize the option.

 

[SacEsq]

All of the above. In theory, I think its a decent idea and use it myself in three or four motor clusters. In reality none of them will fire at the same time but it can't hurt to utilize the option.

THANKS ... its a great idea.

 

[SacEsq]

I think it was suggested more to prevent them all from popping at once, that would be a lot of boom.

I suppose I could use one plugged (do they make those?) one at 5 and one 7 ...

 

[SacEsq]

Here is one pic ... not sure where the others went ...

The paint is Rustoleum Color Shift ... kinda prices, especially for such a big rocket, but it looks great. A pic of the full rocket coming soon.

 

[gpoehlein]

Unless you've changed something basic (nose cone, lengthened or shortened the body tube or changed the fins), the CP will be the same as on a stock Executioner. Check EMRR to see if there is a Rocksim file of it, or the rocket may be listed in the CP library. As long as the CG is at least 2-1/2" ahead of the CP, you'll be fine. Remember to check the CG with the heaviest unfired motors in it.

As for the motors, that thing will rock on either three E9s or the new E12 BP motors from Estes. And if you use Quest Q2G2 igniters, you're almost guaranteed to light all three. Just a thought.

 

[chadrog]

The only problem I see is getting all three motors fired simultaneously. The copperhead that fits those small hobbyline reloads might give you some grief. We tried the new Estes pro igniters and they wouldn't light the E18's Sharon wanted to fly her Starburst 2X cluster on. The copperheads worked for her, but I was really sweating it. She put a lot of work into this discontinued LOC kit:

I painted my Executioner black with red fins and a spot of silver behind the decal so the "executioner" would show up. Went the other way with my MMT and did it in 29mm with the new Estes motor retainer:

That looks really cool with the silver behind the graphic, awesome idea!

 

[SacEsq]

Finally finished this (it was silver in the posts above) and is now Rusto Color Shift Purple/Green. As you can see from the previous pictures I modified this one with the 3x24mm motor mount - the reason for the "Executioner D3" name. I also added a baffle. My son and I flew it twice at TCC Dairy-Aire. First flight only 2 of the D12 engines ignited but still flew well. Second attempt got all 3 motors to go and it was perfect. Very happy with my first cluster.

BIG THANKS to Mark at Stickershock for the great decals for this one.

 

[astroimgur]

But where is the video? op: Great looking rocket...Congrats on the success!

 

[SacEsq]

Sorry no video... I will do better this coming season