Questions for my first High-Power rocket

[MattEx]

Ok, I have the parts for my first High-Power rocket in front of me...
I have a few questions that I really need answers for, and I thought well what better place to ask at than TRF?
The airframe is PML 54mm Phenolic. The idea is to fly 38mm motors in it at first then go to 54mm later by taking out the adapter, and this is the basis for one of my questions below.

Ok here are my problems:

How do I attach my parachute (Aerocon 36") to the rocket?
I have a PML ESH coupler kit thing and the idea was to attach the parachute to the top bulkhead in the ESH by means of a eyebolt, but then I realized that by doing that, it would take the altimeter (Gwiz LC) and electronics mount for a ride on the parachute and abandon the rest of the rocket to the drop awaiting it . The rocket is going to be split into two to aid setting up the altimeter and general accessibillity reasons, with the ESH as a coupler. No, this is *not* a dual-deployment project.

What material do I use for fins, and how should they be attached to the airframe?
Bearing in mind that the rocket will be used a with 54mm motor later down in the line (hint: minimum-diameter project ), what material do you recommend for me to use, and how do I attach the said fins to the airframe (fiberglass, hefty fillets, ?). I can't do a "through-the-wall" fin mount as I wouldn't be able to get the motor in (fins in the way) . I have some West Systems epoxy left over from my KN/Epoxy experiments, can I use this for adhesive purposes (i.e. gluing things together) as I hear it is used for fiberglassing (handy for attaching fins with fiberglass if this is how you do it I guess)?


Thanks for all your help guys,
Matt

 

[matt_taylor]

for attaching your parachute, get a small U Bolt, both burnings and mitre 10 have them, and to keep it in the airframe, you can use a series of bolts that Will hold it in. for the fins, the best would be to use fiberglass, you can buy a sheet from dick-smiths(but it does have copper on one side) and then make some fillets with a big of chopped kevlar or fiberglass , for the best strength , put a layer of either fiberglass or carbon fiber tip to tip over the fins after that you will have no problems with the fins, yea west systems is great for building rockets too.
BTW if you need come carbon fiber i know a place that sells it cheap

matt

 

[als57]

Originally posted by MattEx
Ok, I have the parts for my first High-Power rocket in front of me...
How do I attach my parachute (Aerocon 36") to the rocket?
I have a PML ESH coupler kit thing and the idea was to attach the parachute to the top bulkhead in the ESH by means of a eyebolt, but then I realized that by doing that, it would take the altimeter (Gwiz LC) and electronics mount for a ride on the parachute and abandon the rest of the rocket to the drop awaiting it . The rocket is going to be split into two to aid setting up the altimeter and general accessibillity reasons, with the ESH as a coupler. No, this is *not* a dual-deployment project.

What material do I use for fins, and how should they be attached to the airframe?
Bearing in mind that the rocket will be used a with 54mm motor later down in the line (hint: minimum-diameter project ), what material do you recommend for me to use, and how do I attach the said fins to the airframe (fiberglass, hefty fillets, ?). I can't do a "through-the-wall" fin mount as I wouldn't be able to get the motor in (fins in the way) . I have some West Systems epoxy left over from my KN/Epoxy experiments, can I use this for adhesive purposes (i.e. gluing things together) as I hear it is used for fiberglassing (handy for attaching fins with fiberglass if this is how you do it I guess)?


Thanks for all your help guys,
Matt

Matt:

The West System epoxy is good for most of the stuff you are comtemplating. You didn't mention what hardner you were using. I would suggest you get some of the West System sillica filler ( number is 406 or 407 ) to help thicken the material for fin fillets.

Fin material. Well if its going to stay sub-sonic ; G10 is nice but heavy. Fiberglass laminated plywood is nice and you can bond the cloth to the tube for extra strenght.

For parachute attachment you could put another cenerting ring above the motor mount to clear the longest motor you plan to use and put a u-bolt into it. Use a 29mm hole in the centering ring to give the u-bolt something to grip. Epoxy it in place using some of that filled West System epoxy. Then quick link from the u-bolt to the recovery harness.

Good luck with your project.

Al