What descent rate do you want? I generally go for a 10-12 fps because I like landing soft, especially on our prairie. I make a torodial chute that does very well for the size. On my L3 I used a 60" chute for a 15 pound rocket and got about 17 feet per second.
Edward
That is very interesting. What are you asking for one of your chutes?
Bear, Edward makes nice chute. Something I will point out though, Tripolicolorado.org has a list of vendors that support Colo Rocketry and there is a couple that are local. I am sure many are also on the NCR site. I shop these first and Alpha is on TC's list.
Sorry, I didn't read the 20-25 fps. That's screaming in! At 20 fps I get a 48" parachute with a 17.5 pound recovery weight and recovering at the North Site - 5500'. A 60" parachute gives you 16 fps and a 72" parachute gives you 13 fps.
I've made two different varieties of the parachutes - high performance 1.1 oz ripstop and every day 1.7 oz ripstop. Both perform the same, but the 1.1 oz packs tighter and is lighter. If you don't need to cram 10 pounds into a 5 pound sack, I use the 1.7 oz. I only have 2 1.1 oz chutes and both are for high performance minimum diameter rockets.
The 1.1oz chutes cost more than the 1.7oz because of materials cost and the labor involved in making them.
I don't make anything smaller than 60". 60", 1.1 oz, $105, 1.7oz, $90. 72" 1.1oz, $115, 1.7oz, $100.
My lead time is a bit - generally 3-4 weeks. I just sent back an order of fabric because they didn't get my instructions clearly. I don't sew hemispherical parachutes anymore - I figured if I'm sewing all those gores, I might as well make the most efficient shape that I can out of them. I will sew big flat circles if people want - those are easy to produce.
Also, on colors. I've done many colors of chutes. I've settled that I like pink/black the best. At this year's MHM I didn't know where my rocket had landed, just a general direction. From the 2nd windmill I spotted the pink parachute being backlit by the sun from 3 miles away. I don't think I would have seen any other color. There was just this iridescent flare of pink that caught my eye and led me to the rocket.
Anyway, enough rambling,
Edward
Edward, I had no idea you make chutes.
And they are really nice too!
And they are really nice too!
They're okay 😉
That one is a 96" chute toroidal profile. Let D1's L3 down nice and easy. I make about 10 a year for people - not a whole lot but keeps me busy.
I actually have a 60" you can try if you want to see how they work. It has quite a few feet on it - approaching 65,000'
Edward