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gerbs4me

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I have been working on this project for some time now, its made frome 4"PVC. It has a 38mm mmt, I was thinking of using a Pro38 H153. so far it weigh 3.5 lbs, since I've never made a L2 rocket I thought it was a good idea to glass the CR's to the motor tube and glass the fins to the motor tube as well(haven't done the fins yet) I did this so it will be sturdy, and could take a J motor. I pan on flying it for my L1 May1-2 or June 5-6. I was thinking of naming it either
-Lusty Corn Maiden
-I'm too sexy for my cert.
-Instant Karma


I am also building a X-mas candle rocket, I haven't started building on it yet, its gonna have a 29mm mmt , plexiglass fins, I give you more details once I start building on it.
 

LarryH

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Wow, a PVC bodytube? I'm kinda curious as to how that's gonna work out... I'd have thought it would add too much weight(but since we're talking L-2 not really much of a concern), be a little to brittle(but then, no where near as brittle as phenolic), and at the same time not really stiff enough(if you bend it without breaking it, it dont always return to it's original shape.... but I dont think you'll accordian it like you can with paper tubes), a 4" diameter section of it just might work out perfectly! Are you making a custom nosecone to fit it? Keep us up to date, and where's the PICS?????? :kill:
 

PunkRocketScience

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Hey Gerb-

The Pro38 2g is a great motor to cert on. Much easier to build for a cert. than the other guys....

I would vote for "I'm to sexy for my cert..."
 

Rocketmaniac

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Gerbs....... We need pics.......... I am interested to see how this project turns out......
 

doxiedog315

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How well ,does epoxy stick to PVC? Been wondering about that.
 

Manwithbeers

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"How well ,does epoxy stick to PVC? Been wondering about that."

I've been working on a HP PVC Project for some time now. 2 Stage in fact. It's common knowledge that Epoxy does not stick well to PVC and designing the thing has been a challenge.

TTW Fins at first seems to be a must have design element for fin strength. I built a roll yer own motor tube for my 38mm fincan so that I can have good bonding surfaces between materials. I'm using 4 inch light sewer pipe and plywood fins. Custom EPS Foam core nose cone with fiberglass on outside.

Latter on in the construction process I found a very good tidbit in a West Systems brochure. It saiys that West Systems does not stick to PVC any better than other Epoxy but if you first coat the bonding surface with PVC Glue and let the glue cure the epoxy will bond well to the glue!

My Second fincan now has surface mounted fins so that I can use a thrust plate and that allows me to switch between 38mm, 54mm and 75mm motors if I like. Right now I'm making Centering rings for 54mm motors in that fin can. (Not shown)
 

gerbs4me

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well I guess corn Maiden is out, so I'll name it I'm too sexy for my cert.:)
I turned a foam NC by hand, I'm trying not to rush this rocket, ya can't rush perfection,
 

edwardw

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I don't know if you have built with PVC before, but even thought it's a good material, it isn't exactly the best for rockets. I have used it cause it was cheap.

ABS is much more forgiving than PVC because it almost tears rather than cracks if it is stressed. I had a PVC rocket come in ballistic and it shattered to small pieces. This was a 2" diameter rocket that was 7' tall. The largest pieces were the size of a quarter.

I rebuilt it in ABS and had it come in hard also. The fin can was reusable but the payload section just plowed into the ground and looked like I peeled a banana with the ABS. ABS is also lighter.

I found it really hard to get couplers to fit tight so there was no slop. Also, fin attachement is kind of a pain. I have bolted, hot glued, and done a bunch. So far hot glue is the best, but not really a good glue overall.

Plexiglass fins are extremely brittle. If you get them a little cold and have a hard landing they tend to snap and go all over. I tried plexiglass then went to cardboard soaked in epoxy. Also, if you bolt the fins on don't tighten too much or you will create small stress cracks and then it will crack on a hard landing.

Also, on the Pro 38 website for the H110 2-grain ( I know the H 158 is a little more average thrust) it says that the max takeoff weight is 4.8 lbs. They don't have data for the H 153. I would guess maybe a max takeoff weight of 5.5 lbs.

I am also doing a L1/L2 scratch rocket and have decided to go with 3" mailing tubes for it since I have had bad experiences with PVC and ABS. Also lighter than both.

FWIW,

Edward
 
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