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Which do you prefer?

  • Performance and Altitude

  • Looks

  • Don't know/care

  • Performance and Altitude

  • Looks

  • Don't know/care


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Neil

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First, a note the the moderators.... I dont know exactly where to put this. It could go in MPR because its a MPR capable rocket, but its also HPR capable, but its also a kit I might release soon, so I am very confused. im just putting it here cause I think its my best bet. Feel free to move it to its correct spot if you feel like. Thanks.:)



OK.... I have been playing with the Rocsim design for the kit I am in the process of kitting. I havent cut out the fins yet, so I can still change the design if I feel like it. I was wondering what would be more apealing to you guys... a 3 finned version with triangular fins, or a 4 finned version with fins similar to the LOC Forte. I like both pretty much equally, so I guess your guy's (and gals) oppinions are what will make up my mind. Ill post rocsim imports of both designs in a sec, so you might not want to vote untill you see em. Thanks!
 
Heres the 3 finned version.

BTW, this rocket is 2" diameter, pre glassed (or will be), and has a sandman-made nosecone:cool:
 
I actually kinda like the 3 fins better.... The 4 fins are kinda bulky.:(
 
for a 2" rocket i think three is better.... four is just to much:rolleyes:
a 38mm mmt, i assume? thats what i looks like. i like to cone too... what kind of wood? and, lastly, how much do you think it'll weigh in the end (finished)?
looks good so far, tho;)
 
Yep... 38MM. So those lucky people who live near Black Rock can fly it on J:D ;)

I really dunno yet.... It gonna be glassed, thatll add weight. Well see when I build my boiler plate version.

The cone is wicked durn hard balsa. Very, very hard, and reasonably light. The instructions might call for you to put some epoxy on it if you want to fly it on really big (relatively) motors.

I like the 3 also... Well see what other people think, but Im pretty sure I want to go with 3.:rolleyes:
 
Originally posted by Neil
Im pretty sure I want to go with 3.:rolleyes:
lets see the pros of 3:
-better looks (thats personal prefrence tho)
-lighter
-cheaper
if there are any real pros to the 4 i'm not aware of them:D :rolleyes:
cone sounds sweet... have you gotten any of them yet? (did you even order them?), if so i wana see!!
 
I voted for 3 fins simply becouse 3 = 1/4 less work. I'd go with the Forte style fins though just becouse I think they look cool. They are also less prone to damage.
 
In what way?I think the triangular ones would be safer.:confused: Ill try it out with 3 forte style fins, though.... Ill post a Rsim export in a sec...:D
 
I really dont like it with 3 forte... But thats just me.

I think the 3 triangular ones are better, though...:rolleyes:
 
Originally posted by rocketkid88
lets see the pros of 3:
-better looks (thats personal prefrence tho)
-lighter
-cheaper
if there are any real pros to the 4 i'm not aware of them:D :rolleyes:
cone sounds sweet... have you gotten any of them yet? (did you even order them?), if so i wana see!!

stability
 
Prone to less damage with Forte style becouse if you have it come in on it's side it will hit a long flat fin end rather than a small pointy one. It's not really that important though. The triangular ones the way you have them are fairly tough anyway. I still like the look of the Forte style though!
 
Yes, I have them all. I have a pic somewhere. Ill try and find it for ya.

Yes, stability comes into play... I have to figure out how much noseweight will be neccesary.:rolleyes:

OK. I think I found it. Well see if its the right one.
 
Yep. Thats the right one. Note the thermometer in the middle of the pic...:eek: :kill:
 
Didnt see yer post...


Thats true, but this 1/8" plywood is tough stuff. It would have to land on hard cement with a tangled parachute to dent it....:eek: :eek:
 
So you can choose by style alone then. I've gone with three fins on all my latest non-scale designs. I had a 3" come in flat on it's side with no parachute and didn't get a scratch. A four fin might have done as well but it would have been 1/4 less likely. And like Ryan said, cheaper, lighter, maybe looks better and definatly less work.
 
Originally posted by Ryan S.
stability
there is a slight increase in stability, but with three fins there is also slightly less weather cocking. i guess for every pro there is a con:rolleyes:

Zippy has a point, but i think that you don't really have to wory much unless your launching on a hard surface with a small 'cute

Neil (and Sandman!)- those cones look great! and does that thermometer say its 70.5 outside, or inside:D i see it also says 0.7, may i assume thats the outside temp?? ;) we haven't got it 'quite' so cold here:p
 
Originally posted by Zippy
And like Ryan said, cheaper, lighter, maybe looks better and definatly less work.
errrr... i believe i said that:D he was promoting a four fin design;) j/k
 
Sorry RocketKidd, I guess I creditted the wrong person. It gets very confusing for old folks like me reading all the quotes.
 
Originally posted by Neil
Yes, I have them all. I have a pic somewhere. Ill try and find it for ya.

Yes, stability comes into play... I have to figure out how much noseweight will be neccesary.:rolleyes:

OK. I think I found it. Well see if its the right one.

how are you going to put noseweight in those cones. And if you do, you should definantly glass them because the extra weight will cause them to his harder.

1/8" plywood does seem tough but I really dont think it is that tough, any landing on cement is gonna dent it, with a tangled chute it is probably gonna get dented unless it lands in mud or the chute isnt very tangled
 
well, in a larger fin I might be worried a little, but these fins are pretty small, nomatter which kind I decide to make...:rolleyes: But I doubt the chute will tange. I put extra-long shrouds on em so even if it does tange, it usually opens.:rolleyes:

Yep. .7 degrees outside, 70 inside. And I considerd that slightly warm at the time! It was getting to 20 degrees below without windchill then...:eek: :kill: Insta-frostbite...:eek: :mad:
 
no prob zippy!!! :D :) ;)

so far as nose weight goes, i think that you shouldn't need any for most engines. if you do need some for larger engiens then you should just leave it up to whoever is building the rocket. they can decide if they want to glass it or not and how they want to add weight. Personally i'd just drill two wholes in the NC 180º apart, and melt some lead and poor it in (depends on how much i'd need). but, you can do it however you want (dur!):cool:
 
True true true... Though Sandman ran out of supah-hard (and semi-heavy) balsa, and only had normal hard balsa for the last two... little or no difference in strenth, but quite a bit of difference weight wise.:eek:

I suppose me&my beta tester could take the light ones and put the weight in em, and the hard hard ones would be in the "real" thing.:rolleyes: I havent decided yet....

Either way, there will only be 6 kits in the first batch.:( So that means you cant buy em from yer local hobby shop...;) Only thru me...:cool: ;)

And the pricing.... What would *you* say would be a good price for a pre-glassed, 3fnc 38MM motor mount model? Im thinking about $50 at most, but I am not sure... BTW, the shock cord is braided Kevlar and the chute is 25" ripstop nylon.:cool:
 
i would pay 30.

why dont you use hardwood? Balsa really seems to suck for high power rockets and in a rocket you are going to use for mid and high power I would use hardwood. If you use the hardwood, you wont have to glass them AND you wont need to add as much noseweight because the nose will be heavier and if you do it is less likly to damage your nose
 
Neil, I just want to say that if you actually get these kits out there for sale then "Your a better man than I Gunga Din".
I'm still sitting on 20 plastic BT-50 nosecones for my first kit effort. Now I have a stack of decal paper to go with them so maybe some day...
 
Well, I just toataled up all the parts, and how much they cost. The toatal is about $28. each kit will take between 2 and a half to 4 hours to make (just what I am guessing. I really dont know), so thats $15 at minimum wage, assuming it takes me 2 and a half hours to make. So how does $40-$45 sound? Yank 2" kits cost about that, and those dont come glassed.

If I charged $30, I would make a profit of... Drumrolll..... TWO BUCKS!:eek: ;) :p :rolleyes: :mad: :kill: Not gonna happen. sorry.


Whaddaya mean, "Your a better man than I, gunga jin"? I dont know many quotes. Bear with me, im young.:p gimme time, Ill learn a lot of quotes. Usually from you guys!:p
 
Not to discourage you but those estimates seem mighty low.
A good way to do buisness is to make a fair guess at time and materials and then triple it. If you come in less then you can pass on savings to your customers. Forget about preglassing, that worth $45 alone. You will be very hard pressed to beat Yank's prices especially from large dealers. Remember also part of the attraction to a person who might buy one of your kits is WHO kitted it, particularly true here in the forum.

Gunga Din is in reference to an old movie from an even older book. It's just a phrase I use occaisionaly that I stole from the movie, possibly the book wich I haven't actually read.
 
Liar liar pants on fire!:D ;) I have already bought most of the materials:

Shock cords: braided kevlar. braided by me:D $3 per. 10' long.
BTs: $2, no glass
Glass: $4 per kit
Nose cones: $12 each.
Parachute: $6 each to make. The actual price would be more if I was buying them from myself, but whats the point in that?
Fins/CRs: $5, give or take. I got the plywood in big sheets, but I dont know how much each set of fins will take up.:confused: I have plenty, just in case:cool:
Launch lugs: I forget, but not that much.
MMT:$1
Paper for instructions: $.00000000000000000000000000000001 ;)
Thats all I can think of... I dont see where your getting the higher figure...:confused:

Didnt social studies class tell ya nothin!? Child labors cheap, man!;) :p :D LOL... Couldent resist that one...

The launch lugs are 1/4" LOC, BTW.
 
Wow Neil, child labor must be like free then. Their must be countless hours in all that. More power to ya if you can sell them that cheap though. But don't sell yourself short.
I don't want to argue point by point but how do you get $4 for glassing? It would take me an hour or more just to set up/clean up and another hour or so working time on that wet glass, then its got to sit around 24 hours curing and the like. I assume you allready have the resin and cloth and simply are giving that away free or is the $4 for material and your giving your labor away for free? Either way it's a good deal for the customer. It just seems like your giving alot away like your labor on the 'chutes. I know this doesn't exactly apply to you but it's like a fellow who I highly respected said about his buisness (a bakery although he wasn't a baker) "One part for flour, one part for the baker, one part for me and one for Uncle Sam". He didn't triple cost, he quadroupled it. Anyway it's all light hearted I hope and sign me up for one when your done with them, especially if your signature and Sandman's (nose cone) are both on there. That way I get a 2fer in collectabillity. :)

EDIT: I forgot to mention.. I want the glassed version! :D
 
Those prices were just for the MATERIALS. Im not charging $4 per glassed tube, dont worry:D ;)

So you think $45-$50 is better?

it only takes me half an hour to make a 25" chute... making the shock cord takes longer.... I bought 300' of kevlar from Giant Leap, cut it into 10' sections, and braided it. It took a long time, but it gave me a big sense of accomplishment.

What do YOU think I should sell these for?:confused: Theres a 3" diameter pre-glassed rocket from Skunkworks for $90. That has a fiberglass nosecone, though. So I think that $50 really isnt that bad... but thats just me. Whats your oppinion?

I already have the glass and resin. I was just saying what the glass and resin cost. I will add my labor in later, dont worry;)

Heres my time estimates:

Shockcord: one hour
Parachute: half an hour
Making fins, CRs: I dunno. Im guessing about half an hour, though.
Glassing tube: No idea. 2-3 hours at most, im guessing. my first glassing attemt took about an hour.


so thats about 4 or 5 hours per kit. OUCH. But its still fun... And I get a big sense of accomplishment every time I finish, say, a shockcord, which takes me a lonnnnggg time to make.

Ive already finished all the shockcords, I have teh nosecones, the BTs (ready to glass), the glass, the MMTs, the plywood for the CRs and fins, and I have all but 2 of the chutes sewn.:D In other words, its comin along...

Assuming we can figure out what to charge for em, they will be ready this summer of fall. I dont know. Im halfway through the instructions.:eek: The instructions are a lot more work than I thought they would be.... NOW I know why it takes Jim a while to release kits....:eek: ;) Making ONE kit is hard... I dont know HOW jim manages to make all that he does....:eek:
 
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