how to make multi panneled chutes

[rocketsonly]

Hey all, I was wondering how you all make those multi panneled chutes. I either interested in making my own mylar or nylon chutes. Also, how would you attach the shroud lines?
-Matthew

 

[Micromeister]

Matthew:
awhile back I posted a number of full size gore patterns and the construction info. but I can't recall where I stuck it so I'll try to post the same here. the next 4 or 5 posts will be full size gore patterns for the 6 panel chutes I've been making. Each of the patterns includes 1/2" overlap seam margins that can and should be trimmed after the sewing is completed to reduce bulk. the top spill hole can be adjusted to your liking. Hope this helps.

here's how to layout your own gores.

 

[Micromeister]

I should have mentioned in the develpment diagram posted it's the upper left diagram that is the most helpful.

Heres some completed Hemi chutes, the lower left pic shows all the different size gore pattens hanging in the basement.. as you can see they do get large.

Next pic will show the seaming and spill hole stitching.

 

[Micromeister]

I've been using 70lb kevlar shroud lines in hemi-chutes 6" to 24".
Heavier 130lb kevlar or twisted nylon cord for 30" to 48" chutes. I like the kevlar better then the nylon but if it's all you can find the nylon works OK as long as the chute is well protected from the ejection gases.

 

[Micromeister]

Sheet size restricts the patterns I can load here full size here are the two smallest I normally make in rip-stop nylon, real silk, or even plastic with a monocoat sealing iron and a towel.
6" and 8" gores.

 

[Micromeister]

10" pattern

 

[Micromeister]

12" gore pattern

 

[Micromeister]

15" gore pattern.

This is the largest I can up load here. sorry. but with the development instrustions and seeing what the end product is you should be able to layout your own patten in any size you like within the constraints of your layout room and paper size.

One more note: Because a true Hemispherial parachute catches twice the air volumn of the best developed (inflated) Parasheet. you can decrease the diameter of the hemi-chute you are flying. I am flying a 3.1lb Brighthawk on a single 36" hemi, where I was told I needed a 42 or 48" flat nylon chute.
Hope this helps.

 

[hokkyokusei]

Couple of good links here:

https://www.cit.gu.edu.au/~anthony/kites/parafauna/chute_design/

https://members.aol.com/ricnakk/paracon.html

 

[cls]

I use SpaceCAD to print gore templates. it will print templates for any diameter, any number of gores, and any height hemisphere - pretty nifty!

the trick with ripstop nylon is to get a good hem. get a special "french hem" foot for your wife's sewing machine. this foot does the double-fold-over manuever which will keep your hems from unravelling.

 

[edwardw]

My parachutes I lay out the gores with a compass and a piece of paper. I draw the diameter of chute I want then go at it with the compass. Takes some practice to get the hemispherical ones - but I find it not that hard. As for sewing - ripstop frays in spite of you. A serger machine is nice as it keeps it from fraying.

Edward

 

[Ted Cochran]

Originally posted by rocketsonly
Hey all, I was wondering how you all make those multi panneled chutes. I either interested in making my own mylar or nylon chutes. Also, how would you attach the shroud lines?
-Matthew

Here's a sewing diagram:
https://www.ibiblio.org/pub/archives/rec.models.rockets/PLANS/chute.GIF

The lines for my nylon chutes are run through the tunnel formed by the seams. Over stitch them for an inch or so at the top hem and the bottom hem; it isn't necessary to stitch them all the way up. My suspension lines go over the top of the chute, and are sized so that the distance from the canopy skirt to the attachment point is about 120% of the canopy diameter.

Many of the gore patterns shown so far are hemispheres, which have a lot of extra fabric around the bottom that doesn't add much to drag. A shorter skirt--even a quarter sphere--is more efficient.

If you want to get _really_ fancy, cut each gore in half, hem it to make a gap, and rotate the top disk by one gore from the skirt, like the attached.


Cheers,

--tc