T-Cup Folding Tutorial

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edwardw

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For some time I have wanted to get a tutorial up on how to fold the T-Cup parachute to the smallest dimension I have found yet.

Hope you all find this helpful.

First Step

Fold all the wings over on themselves neatly and make the top triangle as neat as possible. Also line up the edges.
 

edwardw

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Second Step

Fold the triangle on the top over onto the wings. Keep as flat as possible.
 

edwardw

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Third Step

Fold the parachute in half, lengthwise. Fold the sewn curved edges over toward the loose edges. Again, keep as flat as possible.
 

edwardw

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Fourth Step

Fold the parachute in half again, but this time shortwise. Keep the unsewn edges lined up and flat.
 

edwardw

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Fifth Step

Insert a dowel or other bar that won't tear the parachute in the fold. This will be used to pull the fabric tight against when rolling.
 

edwardw

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Sixth Step

Flip the parachute over with the bar in the fold still.
 

edwardw

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Seventh Step

At this juncture, I either employ another helper or two sturdy objects to put the dowel between so I can pull the fabric tight. A helper works great because they can pull it tighter and keep it even. Also, I have been keeping the shroud lines off to the side and out of the way this time. Make sure not to tangle them.

Take the bottom of the chute and fold under, pulling tight. Now fold it over again and start rolling, keeping an even tension until you get all the way to the other end. Once at the other end grasp with your hand around the chute and remove the dowel.
 

edwardw

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This is what it should look like after rolling and removing of the dowel.
 

edwardw

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Here is a 30" T-cup folded and rolled and put inside a 1.52" (38mm) airframe. This is a tight fit but just illustrates how small you can roll it. The night before my flights I usually roll the chute and put in the airframe. Then once at the field I unroll and shake it out. I think it helps to get the fold creases in there when folding in the field.
 

edwardw

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Here is the total length of a 30" T-Cup rolled. Around 8" long and 38 mm in diameter. Should fit really nicely in a 2" airframe with a nomex cloth around it for protection.



Edward
 

edwardw

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If you have any questions I would be happy to answer them for you. It takes a little bit but this is the best way I have found to get the smallest chute so far. Hope this helps!!!

Edward
 

teflonrocketry1

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Edward,

Can you post a picture of the canopy fully open?

Bruce S. Levison, NAR #69055
 

wwattles

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Edward, I know that your company makes those T-Cup chutes, but they aren't mentioned anywhere on the STL website. What are the smallest sizes you make, and are they all custom-order creations? Reason I ask is that I like using fun and different chutes (and can't stand cheap plastic Estes chutes), but I also usually fly LPR where cloth chutes need to be fairly small to fit my rockets. Can you give us an approximate pricing range?

WW
 

edwardw

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I don't have them on the site yet...I have not updated it in a while. I have been busy planning my wedding and such. I will try to this weekend.

To answer your questions, the smallest in the T-cup is a 12" one. That means the main triangle measures 12" on each side. They step up in 6" increments on the main triangle. The wings follow accordingly. I have some standard colors, but I do make them on an order by order basis. I try to give you as much of a choice on colors as possible. I think right now I have ten different colors of cloth in stock. As for a price range, they start at 12" for $15 (including shipping) and go up to a couple hundred dollars as they get bigger. I will post the price sheet and a picture of the canopy when I get back to my house.

Edward
 

edwardw

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Here is a picture of the canopy opened as best as possible. That is a 36" ruler at the bottom for scale.


Here is the price list:
12" $15
18" $20
24" $27
30" $35
36" $40
42" $47
48" $55
54" $60
60" $70

Edward
 

powderburner

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hi edwardw,

Can you explain what the advantage is for this 'chute design?
Is it easier to make, or more stable during descent, or what?
(Do you have any photos of one of these canopies inflated?)
 

edwardw

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The chute is just another design you can recover your rocket under. It is a little more fun and flashy than a regular chute. When I did my L1/L2 certs with a 48" parachute like this it didn't spin on me at all. Provided a nice descent rate. Even on my L2 cert when one of the shroud lines got tangled and was about 2 feet shorter because of the tangle it spun, but still landed safely. L1 descent was 10fps, and with the spinning on L2 it was about 12.5 fps.

Here is a picture of Eugenefl's Der Red Max on a 30" T-Cup.

That's the only good image, as my cert attempt it was windy and they drifted quite a ways.


Also, here is a thread about the T-Cup if you want more information.
https://www.rocketryforum.com/showthread.php?s=&threadid=8167

Edward
 

eugenefl

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Edit: LOL! Edward and I replied at the same exact time. I'm using the headphones to listen to the Tampa Bay Lightning battle the Flyers in Game 7. GO BOLTS!

Originally posted by powderburner
hi edwardw,

Can you explain what the advantage is for this 'chute design?
Is it easier to make, or more stable during descent, or what?
(Do you have any photos of one of these canopies inflated?)
It's cool!

It appears to be a much more stable decent. On my 4" Der Red Max, a standard LOC round 36" makes the nosecone twirl around the lines.

For a decent recovery photo, check this out: <a href="https://www.rocketryforum.com/attachment.php?s=&postid=86769">DRM Recovery</a>.

Full T-Cup review: <a href="https://www.rocketryforum.com/showthread.php?s=&threadid=8167">Full Review</a>
 

powderburner

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That is a cool-looking parachute, or T-cup, or whatever you call it.
I may just have to place an order . .
 

Johnnie

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Edward is still working the details, but the T-cup is on my list for a large L3 chute!

I have seen only 1 chute oscillate like a Jelly fish as it descends...as I understand it, the T-cup does this as well. This sold me right away.

I'm also a big fan of the "X" chute...very unique as not many fliers fly them...But I do.

I will remember this thread and technique when it comes time to stuff that "T" in a 5.5" dia X 18" long payload section...
 

edwardw

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Good to know I have 18" long and 5.5 inches to stuff the chute into :) I'll be keeping that in mind as I build it. So far it's going to be pretty big. I'll try to keep yours in a 4.5" tube so you can nomex it. Weight - I'm guessing almost 3 lbs for the chute with all the nylon strapping re-enforcing.

Edward
 

DPatell

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This may have already been discussed, but are your prices comparable to Skyangle and Rocketman? I may be in the market soon for a chute for my Magnum clone...should be 20-30 pounds.
 

edwardw

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A Skyangle Cert III Large drops 16 to 35 lbs and costs roughly $130.

A Rocketman R14C drops 20 to 35 lbs and costs about $135.

On each of these the 35 lbs is at 20fps. I'm not comfortable really with 20fps, I stray toward the 10-15 fps group.

In the long run, these companies will make more off their chutes than me, why? They can buy large quantities of raw material. They probably can get it done faster because they have more people.

Me, I'm a guy with a great sewing machine who really enjoys making parachutes and seeing people use them. I really like it. If you factor in labor, I probably only make about $2 to $3 an per hour. I always will cover my materials, but not always my time. That's okay with me for now, but if I want to develop the company more, I'll have to get better at making these. Hard because each one is hand cut, hand sewn on the machine and pre-tested for your weight. I do this because I want to make sure you will get your rocket back if the parachute comes out and opens. I'm big on you getting exactly what you want with the parachute. I want you to feel that this chute was made for your rocket and you chose what you wanted. I don't want you to think you got an off the shelf this looks like it will work parachute. Just my way of doing business. I'm an old fashioned handshake seals the deal for me kind of guy.


Edward


To answer your question, yes, I could probably do a parachute for around the prices of these other dealers. Don't quote me but I would need more specifics.
 

OKTurbo

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Hey Edward,

How about a pictorial, how to properly fold up a X-Form chute?

John
 

Fore Check

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LOL, I just found this thread -

Me thinks the chute used in this tutorial is on it's way to me right now for my USS Atlantis upscale.... :cool:

I'm glad I can roll it to 8" long - it should fit nicely.

I normally use regular old wadding, though - I'll probably put about 5 or 6 sheets in each of the stuffer tubes to conserve space. I've got about 12" of airframe above the stuffers for the parachute and shock cord (this 12" is minus the nose cone shoulder; 13 5/8" overall above the stuffers.


The color combo we went with sure looks nice! Should match the rocket very well.



----

One final question on the tutorial: What to do with the shroud lines? Wrap them around the 'chute? Stuff them in the airframe on top of the chute?
 

edwardw

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Shroud lines, I typically use small rubber bands from the hair care section of Wal*Mart. They are black and cost $.99 for a bag of 250. I just gather the lines up in a z-fold fashion then put one rubber band on each end, about 1/2" from the end. When it deploys it pulls right off.

Edward
 

Fore Check

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Got the chute today, Edward! Great job!

I took the time to mess around with it a bit.

Folding it per the tutorial was a breeze, except that omitted the part about inserting a dowel and pulling it tight while rolling it up.

It fits beautifully in my BT70, plenty of extra room around the sides between the chute and tube. And it's just about right as far as being compact from top to bottom. With wadding in there, it should be a nice package right up to the nose cone shoulder.

----

But here's the question. In order to get things to fit vertically within the airframe, I'd feel a *LOT* more comfortable wrapping the shroud lines around the rolled up chute.

Do you see a problem with this? I did some "fake" deployments in the front yard by rolling up the chute and then wrapping the shroud lines around it. Then, holding the attachment loop, giving it a slight flip into the stiff breeze we have here today so that the wind would pull it out and unfurl it.

Seemed to work just fine on a couple of attempts, expect that the shroud lines were twisted about 2/3 of their length from the chute to the attachment loop (which I suppose gives a "reefing" effect.)

I didn't have a swivel attached to the loop yet, so I am not certain if this is an acceptable situation that will correct itself upon descent. Or, if those twists remain, will it significantly hamper the performance of the chute?

I tried the Z fold method, and kept getting the dad-gummed lines tangled....

On the Z fold, do you fold the entire shroud lines into three equal lengths and that's it? Or is it more of an accordian fold with many more equal lengths?
 

edwardw

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If you feel comfortable wrapping, then that is good. If it deploys smooth and doesn't tangle then go for it :) But one solution to the twisting is instead of wrapping the lines around the parachute - roll the parachute and have the lines feed and wrap around it :) It's an easy fix. Also, when I z-fold, I should have clarified, I make it about 6" long and then just keep folding to match that 6". Then I rubber band it.

The twist should not effect performance significantly, except you might get some spin. My chute did just fine with one line tangled and 2 feet shorter. It just spun.

HTH and feel free to ask more questions,

Edward
 

Fore Check

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Gotcha. Roll, don't wrap.

I really am please how well it fits in the allotted space in the airframe. :D I was worried. ;)
 

edwardw

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It's truly amazing how much fabric will fit into a small space. The 24" one would have left a *lot* of room. But this one will bring that rocket down nice and sloooooow. :cool: Be sure to have those walking shoes for recovery. Something tells me it might want to travel a little.


Edward
 
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