Boyce Maxi Brute Pershing.

[jazzviper1]

WOW! I just finished assembling this kit and just got it balanced. Over a pound of clay and lead in the nose. She had to balance one inch back from the nose shoulder with a "G" installed. Total weight is just over 2 pounds without motor. It is a great kit I was just stunned by the weight. Can't wait to get painted.

 

[dpower]

Boyce says: "Once assembled, this impressive kit measures 40.9 inches and weighs just 17.6 ounces." Is there a lot of weight aft to need so much NW? The Estes kit only had an ounce or two of NW, IIRC, though mine weighs 17 oz now with various repairs.

Post pics when painted!

 

[James Duffy]

The Pershing design has an immense nose cone, perhaps 40%+ of the total length of the rocket. Further, it has tiny fins, and three of them are in the wrong place. So, nose weight is the cure.

For the Boyce version I will speculate that the additional nose weight is to compensate for the added mass of the recommended G motor.

'Tis cool, though.

 

[jazzviper1]

The Pershing design has an immense nose cone, perhaps 40%+ of the total length of the rocket. Further, it has tiny fins, and three of them are in the wrong place. So, nose weight is the cure.

For the Boyce version I will speculate that the additional nose weight is to compensate for the added mass of the recommended G motor.

'Tis cool, though.

View attachment 565937

You are correct in your reasoning, but I was still shocked. Quite frankly I was amazed that it only weighed in at just over 2 pounds, it feels more like 8 pounds.
She is going to get a 4 foot chute, RockKSim says 44 inches for 15 fps so a four footer should have a good safety margin. Looking at around 900 ft with a G-40-7.

 

[burkefj]

You are correct in your reasoning, but I was still shocked. Quite frankly I was amazed that it only weighed in at just over 2 pounds, it feels more like 8 pounds.
She is going to get a 4 foot chute, RockKSim says 44 inches for 15 fps so a four footer should have a good safety margin. Looking at around 900 ft with a G-40-7.

Mine is at 35.6 oz with a single 36" nylon chute and balasted with a G74 rtf. Using a G-80 or G77/78/79/64 are slightly heavier and will need more weight of course but 48 oz is a bit heavy handed..

 

[jazzviper1]

Mine is at 35.6 oz with a single 36" nylon chute and balasted with a G74 rtf. Using a G-80 or G77/78/79/64 are slightly heavier and will need more weight of course but 48 oz is a bit heavy handed..

The instructions call for 2 36 inch chutes, 35.6 ounces is over 2 pounds. It must drop like a stone with only a single 36 inch chute.
Edit: just checked, that is 18 feet per second. That is the equivalent of throwing it off of an 8 foot high wall. Ouch.

 

[burkefj]

The instructions call for 2 36 inch chutes, 35.6 ounces is over 2 pounds. It must drop like a stone with only a single 36 inch chute.
Edit: just checked, that is 18 feet per second. That is the equivalent of throwing it off of an 8 foot high wall. Ouch.

No you're incorrect 35 is just over 2 lb and when you count the burnt propellant the recovery weight is right at 2 lb and a 36 inch chute is just fine. Plus those fins are pretty small at the bottom and they're pretty sturdy unless you're landing on something really hard. I think they spec two chutes to try to keep the two heavy pieces away from each other but I use a really really long Kevlar shock cord and I haven't had any problem with them banging into each other and the single chute is less prone to failure than a pair of chutes in my experience. Mine should actually be an ounce or so lighter but I didn't have a single piece of BT 101 so I had to use two pieces with a coupler.

 

[jazzviper1]

No you're incorrect 35 is just over 2 lb and when you count the burnt propellant the recovery weight is right at 2 lb and a 36 Oz chute is just fine. Plus those fins are pretty small at the bottom and they're pretty sturdy unless you're landing on something really hard. I think they spec two chutes to try to keep the two heavy pieces away from each other but I use a really really long Kevlar shock cord and I haven't had any problem with them banging into each other and the single chute is less prone to failure than a pair of chutes in my experience. Mine should actually be an ounce or so lighter but I didn't have a single piece of BT 101 so I had to use two pieces with a coupler.

What is a 36 Oz chute?

 

[burkefj]

What is a 36 Oz chute?

That was a typo I meant 36-in

 

[jazzviper1]

She is finished! Altogether a great kit. Only drawback is the water slide decals are printed on clear with out any white underneath. They don't show up well on the O.D. paint. I would suggest Tango PaPa or Sticker Shock (I went with these).

 

[dpower]

Looks great!

 

[sriegel]

Any flight pics? Just came across the thread. Looks gorgeous.

 

[Daddyisabar]

Golly, I sure don't like all that stinking, no good, performance robbing nose weight weighing down my birds and sucking up all that lovely thrust from awesome, yet expensive motors. Why, why so much required? Never could figure it out. Rocket science is hard.

Why do tiny fins on the bottom and big fins up front look so cool?

Why do all the old dudes love that paint scheme so much while the Scout Moms privately tell me they think it's rather ugly? Clashing orange and green horizontal stripes are a surefire fashion fopaux.

So many Pershing 1A questions!