Is this a Good Idea?

It is my first time doing any midpower rocketry. I ordered a package of estes E's, a 9" bt50 body tube, some balsa for fin, a nosecone, an engine block, and a parachute and shockcord. I don't see why this wouldn't work for estes E engines, as I have plenty of lowpower experience. However, would I be able to get a 24/40 rms kit and use aerotech d/e/f reloads in this rocket, or should I buy a kit? I know I will need another ignition system, and possibly a larger pad, but will the rocket work with the rms? What are the best/cheapest reloads for this kit. Also, should I buy this kit for use with an rms:https://www.valuerockets.com/product_details.aspx?pid=7&itemid=14. If I should, should I use the adaptor and use a 24/40, or should I splurge on a 29?
My budget is very limited. Thanks!

Splurge on a 29! Get the 29/40-120 Rousetech case from Redarrowhobbies.com $35.99


If you have to have the aerotech version, it's available for the same price at hobbylinc.com


Braden

UPscaler said:

Splurge on a 29! Get the 29/40-120 Rousetech case from Redarrowhobbies.com $35.99


If you have to have the aerotech version, it's available for the same price at hobbylinc.com


Braden

Click to expand...

Will the reloads be much more expensive? Do you have any advice for my first question about the non-kit rocket? Thanks!

If you can fly an Estes E, you can fly the RMS 24/40. The motor retention may be different depending on how you built the rocket. The RMS aft closure is the thrust ring that can't fit inside the BT. If you use a motor hook for Estes E motors, then the same spacer you would use to fly an Estes D will be needed to use the hook with an RMS case. Just cut a 1" long piece off the end of a used Estes E motor.

If you use the motor hook, I recommend wiring it to the RMS nozzle to ensure the hook doesn't open and you lose your motor case on ejection. See attached photo.


As for the cost of the reloads, buying 24/40 reloads through Hobbylinc or Winkies should cost less then Estes E's for D and E and slightly more for F loads.

I might go with a kit, because I would like a stepping stone into MPR, so that your rocket doesn't accidentally mess up, and lose your case or something. But YES. Definitely splurge on the 29/40-120. I have that and it is a very useful case, as it is so versatile.

eggplant said:

It is my first time doing any midpower rocketry. I ordered a package of estes E's, a 9" bt50 body tube, some balsa for fin, a nosecone, an engine block, and a parachute and shockcord. I don't see why this wouldn't work for estes E engines, as I have plenty of lowpower experience. However, would I be able to get a 24/40 rms kit and use aerotech d/e/f reloads in this rocket, or should I buy a kit? I know I will need another ignition system, and possibly a larger pad, but will the rocket work with the rms? What are the best/cheapest reloads for this kit. Also, should I buy this kit for use with an rms:https://www.valuerockets.com/product_details.aspx?pid=7&itemid=14. If I should, should I use the adaptor and use a 24/40, or should I splurge on a 29?
My budget is very limited. Thanks!

Click to expand...

I'm somewhat confused - are you talking about a 24mm minimum diameter rocket? From your description, it sounds like an Alpha (8.75" BT-50 tube, balsa fins and nose cone) with an E Motor mount. Rocsim says such a beast will do 3200 feet on an E9-8 so I'd be really surprised if you'd get it back. I sure wouldn't want to risk a reload casing in one of these.

Now, if you are talking about using that 9" BT-50 as a short stuffer tube in a larger (BT-60 or BT-80), that is a totally different animal. An E or F motor in something like a Maxi Alpha (Estes is bringing back the Maxi Alpha 3 this year) or a Big Daddy is great. I built a tube finned Big Daddy with 7 BT-80 tube fins and a 3x24mm motor mount - it totally rocks on three E9 motors (which equals a small G).

As far as support gear, you'll need a larger launch pad with a larger and longer rod (1/4" rod, minimum 4' long recommended) and a launch controller with a longer cord. You'll also need a larger launch field (gotta be further away from the pad with higher power).

UPscaler said:

Splurge on a 29! Get the 29/40-120 Rousetech case from Redarrowhobbies.com $35.99


If you have to have the aerotech version, it's available for the same price at hobbylinc.com


Braden

Click to expand...

gpoehlein said:

I'm somewhat confused - are you talking about a 24mm minimum diameter rocket? From your description, it sounds like an Alpha (8.75" BT-50 tube, balsa fins and nose cone) with an E Motor mount. Rocsim says such a beast will do 3200 feet on an E9-8 so I'd be really surprised if you'd get it back. I sure wouldn't want to risk a reload casing in one of these.

Now, if you are talking about using that 9" BT-50 as a short stuffer tube in a larger (BT-60 or BT-80), that is a totally different animal. An E or F motor in something like a Maxi Alpha (Estes is bringing back the Maxi Alpha 3 this year) or a Big Daddy is great. I built a tube finned Big Daddy with 7 BT-80 tube fins and a 3x24mm motor mount - it totally rocks on three E9 motors (which equals a small G).

As far as support gear, you'll need a larger launch pad with a larger and longer rod (1/4" rod, minimum 4' long recommended) and a launch controller with a longer cord. You'll also need a larger launch field (gotta be further away from the pad with higher power).

Click to expand...

Wow! What # of and shape fins did you use? OpenRocket said it would go around 1500-1750 feet on an Estes E9-6. I am going to use the casing in the bigger one with the kit. However, if I did use the casing in the smaller one, and used a D15, or even lower, could I recover it? Also, which 29mm reloads should I use in the larger rocket for the best deal?

eggplant said:

Also, should I buy this kit for use with an rms:https://www.valuerockets.com/product_details.aspx?pid=7&itemid=14.

Click to expand...

The launcher by itself is $111.99 on the Aerotech website The rocket is a Cheetah without the decals. Aerotech sells the Cheetah for $54.99 with the decals. Personally, I think it's a good deal.

Egg: Put a 29mm MMT in it, you can always adapt down to a 24...
masking tape works mostly...
(how you adapt should be another thread)

29/40-120 is great hardware, reloads are easy to come by, and not mostly expensive, 12 to 16.00 per flight i imagine...
i have one , havent flown it in some time and went to the 29mm easy acess..
cti makes low power 29mm(but is hazmat so local retailers wont have it, and then i would only buy from onsite dealer-but i wont fly cti and thats another story)
the 24/40 i believe are 10-15 bucks for 3 flights
SO the cost is exponentially cheaper.. (less power tho)

BUT, build your rocket to be able to put a bigger motor in it if you want to...
even if you mostly adapt it down to fly it..
(this is a hint all HPR flyers learn) a 4" rocket with a 38mm, can never fly a 54mm motor.. but all the 54mm rockets out there can fly a 38mm.
3"mmt would be optimal, but i on my last 4" put a 54mm in it because i doubt i will fly a coke-can 3" motor, and it wont survive a mach flight (quantum tube).

An addage you hear handed down, is you can adapt down, you cant adapt up!, put the biggest pipe in you can fit...
(mininum diameter is another thing)
So if you can fit a 29mm in it that is what i suggest, even if you fly 24mm motors.

eggplant said:

Wow! What # of and shape fins did you use? OpenRocket said it would go around 1500-1750 feet on an Estes E9-6. I am going to use the casing in the bigger one with the kit. However, if I did use the casing in the smaller one, and used a D15, or even lower, could I recover it? Also, which 29mm reloads should I use in the larger rocket for the best deal?

Click to expand...

I took the standard Rocsim file of the Estes Alpha from EMRR, took the 18mm motor mount out, used the front centering ring as a motor block and simmed it with an E9-8. But, again, the Alpha is a BT-50 model, so would be a minimum diameter model for a 24mm motor. Is that what you are simming or are you simming a rocket with a larger body tube and a 24mm motor mount. Given that you are also talking about using a 29mm reload, I am assuming the latter, but you aren't giving any particulars about your design. You sure won't be able to fit a 29mm motor in an Alpha. What size (diameter and length) is your main body tube?

gpoehlein said:

I took the standard Rocsim file of the Estes Alpha from EMRR, took the 18mm motor mount out, used the front centering ring as a motor block and simmed it with an E9-8. But, again, the Alpha is a BT-50 model, so would be a minimum diameter model for a 24mm motor. Is that what you are simming or are you simming a rocket with a larger body tube and a 24mm motor mount. Given that you are also talking about using a 29mm reload, I am assuming the latter, but you aren't giving any particulars about your design. You sure won't be able to fit a 29mm motor in an Alpha. What size (diameter and length) is your main body tube?

Click to expand...

I was using a bt50 9'' in the rocket I am scratchbuilding.

That's kind of what I thought - a 29mm motor will not fit in that rocket - it is too large. Rocsim may be overly optimistic on the altitude, but I still don't think I'd risk a reload casing in it. Too much chance it won't come home.

Many people have upgraded 24mm Estes-type kits for AP reloads (I'm also hoping to try MPR this year).

Search EMRR for Executioner, Interceptor-E, Big Bertha, (and you'll find other models). See what upgrades they made (OK, some of them way overdo it).

Apogee Components online newsletter is pure gold for scratchbuilding. Look at this issue on papering fins -- a cheap way to fly balsa at higher speeds.

https://www.apogeerockets.com/education/downloads/Newsletter250.pdf