spool build guidance

I kind of want to build a spool, but have no idea what I am doing. Probably 38mm motors and in the 1-3 foot size, but not sure yet.

I found a build thread or two that I could half way follow, but no guide more comprehensive than that. Anyone know of such a resource?

I've never seen a guide per se...just the build threads.

1. Find spool (about 12" dia by 10" tall is a good one)
2. Figure out how to put a 38mm motor mount up the center
3. Insert a Loki I110 moon burner
4. Place on pad
5. Hit button
6. Wipe S**T eating grin off your face.

Seriously, don't over-think a spool, just fly it.

Oh, are most flown without parachutes?

I didn't think any high power rocket could be flown without active recovery.

H_Rocket said:

1. Find spool (about 12" dia by 10" tall is a good one)
2. Figure out how to put a 38mm motor mount up the center
3. Insert a Loki I110 moon burner
4. Place on pad
5. Hit button
6. Wipe S**T eating grin off your face.

Seriously, don't over-think a spool, just fly it.

Click to expand...

oint:oint:oint:

That's about how I did mine. Since mine was plastic, I added a ply ring on the butt end to act as a thrust ring. The shock tether is run through the top plate and tied around the core. I use a small chute that is stuffed in the tube with no cap. Lots of fun...needs a very short delay as these tend to stop quickly after the thrust runs out.

watermelonman said:

Oh, are most flown without parachutes?

Click to expand...

Low power, yes (such as those made from CDs). High power needs a 'chute. Mid power...you gotta judge for yourself.

A couple of months ago I managed to pick up a wire spool.
The center hole is perfect for a 29mm motor.
I am going to cut the tube with a 6grain in mind, and will leave another 4" of motor tube over that. Stuff parachute in motor tube above the ejection charge.
Set ejection charge for only 2-3 seconds.

rstaff3 said:

Low power, yes (such as those made from CDs). High power needs a 'chute. Mid power...you gotta judge for yourself.

Click to expand...

I'm unaware of any rule that specifically requires parachutes. You need a safe descent rate. How you achieve that is up to you. Larger spools are unsafe without chutes, too high area loading. Many other types of drags rockets are perfectly safe with aerobrake recovery if designed for it.

You do need an "active recovery device" for certification flights. I understand that OP is not looking to use this spool for certification.

Ari.

I was not referring to any rule for certing or otherwise. I've made several and seen many and they all tumble on the way down, unlike most saucers, pyramids, etc. ie they don't aerobrake. So, in my book an HPR spool needs a 'chute.

Be safe and use a chute. If a spool that size hits someone, car, building it won't be good.

The easiest spool I have done was with the spools from Atwoods, in their cable/rope department. The ones I have spoken to, throw the spools away, when they are empty, so I got them free. They have caps on the ends that are screw on, but may be glued, or have a rivet to drill out first. When you take the end cap out, I drilled it out to 38mm size, however as it is all plastic I put a 29mm adapter in it, to keep the motor heat off of the plastic. Looped some kevlar through a hole I drilled in the tube at the top end, and attached a 24mm nylon parachute. Used a wire at the motor end as a motor retainer, and drilled matching holes for the launch rod, int the top and bottom ends. To load, just unscrew the end, insert motor, and screw end back on.

To add to what rstaff3 posted I've flown MMX to D12 powered (8" diameter x 9" long) Spools. All back tumble (rapidly) after burnout. Micro and up to C6 powered 4" diameter CD size spools recovery OK on grass, but the D12 has broken a least one disc every single flight. So it now has a small chute stuffed in the forward end.
Anything Larger would (SHOULD) have a Chute to slow it down. ALL motor size and disc size Spools rockets from 1" to 8" fall very fast.

I have a LOC "Cool Spool" which uses 29mm F & G motors. I'll provide the dimensions so you can use as a rough guide for upscaling to 38mm if you want to go that route. Note that it has parachute recovery (I heard it was a requirement under NAR and/or Tripoli rules for this size spool).

Width of discs = 65mm
Height = 222mm
Main outer body tube = 45mm
Chute = 18"

I know the only place you can still get the LOC Cool Spool...

cbrarick said:

I know the only place you can still get the LOC Cool Spool...

Click to expand...

I know you have one less Rick!

yah :> but when I bought out the remainder of the spools, they came in two very large boxes! Still have plenty!

KenECoyote said:

I have a LOC "Cool Spool" which uses 29mm F & G motors. I'll provide the dimensions so you can use as a rough guide for upscaling to 38mm if you want to go that route. Note that it has parachute recovery (I heard it was a requirement under NAR and/or Tripoli rules for this size spool).

Width of discs = 65mm
Height = 222mm
Main outer body tube = 45mm
Chute = 18"

Click to expand...

Thanks a ton! I am going to give this a shot at some point.