Welding Capri Sun Pouches

I'm a little miffed at Kraft for heavily marketing these things because they aren't recyclable.  So instead of doing something about it, they engaged in a distraction campaign with their Terracycle program.  But at least you can earn money for your kids school which is cool.

Unfortunately I can't get completely miffed about it because I love a couple of flavors of capri sun.  Plus it's handy as heck to pop them in the freezer then pop them in my lunch box cooler.  They serve a dual purpose here.  They keep things cool in the lunchbox cooler, and by the time lunch is around they have thawed out.

The other thing I love about these things is all the cool things I've seen people make with them.  Wallets, purses, bags, you name it.  Just do a google search for "capri sun projects" or "DIY capri sun".  You'll see what I mean

I have a bit higher aspirations than that.  I want to try making an umbrella or a tent out of them.  But the tent might be a bit ambitious.  Most people sew them together with thread, fishing line, or upholstery thread.   Or they will tape them together with Duct Tape or Gorilla Tape.  I wanted to weld them together.

At first I looked into how they do it industrially.  Apparently they either use microwaves or ultrasonic welding.  Do-able, but not for everyone.  Certainly not with parts I had laying around the house, and certainly not cheap.

In the end I found a soldering iron or wood burner works like a charm.

Step 1: The science...

So a little google-ing and I found what they are made out of...

What is CAPRI SUN packaging made from? Is it recyclable?
CAPRI SUN pouches are polyester-reverse side printed to aluminum then laminated to polyethylene (a plastic polymer). Unfortunately, this packaging is not recyclable.

So it looks like a laminate of aluminum foil and polyethylene.  Ok fine.  What is the melting temperature of polyethylene?   A quick trip over to Wikipedia and I had my answer.  I love Wikipedia, best invention ever.  The nobel prize should go to the guys that invented it.  They are certainly more deserving than a couple of the past winners.

From Wikipedia:

For common commercial grades of medium- and high-density polyethylene the melting point is typically in the range 120 to 130 °C (250 to 265 °F). The melting point for average, commercial, low-density polyethylene is typically 105 to 115 °C (220 to 240 °F).

Ok so the melting point is somwhere between 220°F (115°C) and 265°F (130°C).  Ok, that shouldn't be a big problem.  I think clothes irons only get up to about 200°F so I'm thinking an Iron wouldn't work.

Comments

[sculptur]

thanks awesome ible im going to try to make a back pack as soon as i get enough pouches :)

[DrPeper]

Thank you! I can NOT wait to see a backpack made from CapriSun pouches! How cool would that be???!

[Monkey1234]

Hi I work for a well known drinks co. In the uk and I have a lot of brand new unfilled and unsealed Capri sun pouches I had the idea of filling them with alcohol like vodka "" to make those expensive nights out a bit cheaper" lol I see ur quite interested in these pouches if u like I can send u a bunch through the post let mr know .. Ps not sure if ur aware but the unsealed packs have a strip of heat activated adhesive built-in at the top..

[CosmicBrambleclaw]

If you still have them I would love to get some :D

[RaisingAlexis]

I'd love to put your pouches to use - we are trying to collect them for our Girl Scout Troop to use for a charity project. If you are still interested in passing them on, please let me know! Thanks.

[DrPeper]

Well THANK YOU very much for the offer, but the wife is already mad at me for keeping the 20 or so I have for testing and experimentation. Once I get the bag welding down, then I'll need more bags to make things from them.

However you did give me a good idea. Perhaps putting some material that would act like solder flux between the bags before welding them would aid in the weld.

[Misstongshil]

hi~! this was pretty cool! just wanted to comment: i've seen tutorials for making DIY material out of plastic grocery bags by "welding" them together. the person would flatten out the bags on the fold/seam lines. take a ruler and draw a line straight across the top right where the handles attach and straight across the bottom almost right on the edge. then cut up one of the side seam/edges. now you'll have a flat long piece. do the same to about however many layers you want; the more the stronger. then the person setup their ironing board, wax paper, lined up the layers of prepped grocery bags, another layer of wax paper and ironed away. tada! and if there's a cool logo from a bag, cut it out and put it where you want it, once again sandwich with wax paper, iron, tada! :D - very sewable material in the end too. once made a messenger bag!~ :O :D

[DrPeper]

Yes, I have seen the projects of welding plastic together from sheets of plastic grocery bags. I've even tried it myself and was less than impressed with the end product. I found you need even heat and pressure in order to end up with a good end product and I was unable to achieve that with an iron. My end result had plenty of air bubbles in it that I felt detracted from the usability of the plastic.

[thebigguy62]

I checked out this instructable, very cool. Girlfriend wanted to go to the beauty supply store yesterday, wandered in after her, on the way out I noticed a pile of flat irons, the type folks use to straighten their hair with. The cost was way too much for me to consider experimenting with, $50 to $100, but some of them have variable temperature controls, from 200 to 400 degrees. Seems to me it'd be well suited for what y'all are trying to do. If I should stumble upon one in a thrift shop, I'll go mug a kid for their drinks and try it out.

Chris

[DrPeper]

Oh you know I hadn't thought of those. I just happened to be in Goodwill yesterday but didn't see any with variable temperature controls. I suppose I could hook it up to a potentiometer and manually measure the heat. But I'd rather find one with the heat controls built in. I'll keep my eyes open for one from now on. Thanks!

[sclausson]

I have a Mini Iron made by Clover Needlecraft, Inc. Its ironing surface measures 1" x 1 3/8" . It is used for quilting and appliqueing. It has a 9" handle. I am going to test it on some Capri Sun and other foil lined packaging.

[kroekele]

I've seen a miniature iron used in quilting and craft work at JoAnn's that might work. It looks reminiscent of a soldering iron, but has various tips at least 2 of which might work. You can find it listed as "Clover® Mini Iron II & Assortment Tips". They sell for about $60, but JoAnn's offers coupons each week, or if luck is with you, perhaps find one at a yard sale. Nice job on the instructable. I'm going to try it.

[DrPeper]

Now that mini iron thing is an interesting little thing. I'm looking into it because it might be useful for other projects as well. I've found it's a combination of pressure and heat. So I'm thinking that I need something that gets hot, is rigid enough to clamp two pouches together, and can cool down. So my latest thought is to use a piece of copper pipe to clamp the two pouches together tightly. Then use something like an clothes iron to heat the pipe up. Thank you for the info and comment!

[heathbar64]

 I too was inspired by that ible where he used a soldering iron to make pouches out of freezer bag. I didn't have much success with the soldering iron, so I tried using my Seal a Meal heat sealer(Yardsale find) it was a little too hot for the ziploc bags, but I had success when I plugged it into a heat controller for a soldering iron. the heat controllers are sold for use with leaded glass work, and I found mine where else but a yard sale. 

[DrPeper]

I remember seeing heat controllers for soldering irons. Haven't seen one in years but that is an interesting idea to use it with the seal-a-meal. If I can pick one up cheap somewhere I want to try your idea. Thanks for the info!

[kill-a-watt]

I've used an iron before.

Of course, I've been resealing MRE pouches, potato chip bags, and the like for forever. It's great to seal up stuff like cigarette lighters so they stay waterproof while hiking

I remember having to adjust the heat down slightly from the top of the range. I also put some newspaper down so I don't accidental seal it to the ironing board.

try google/youtube with seal mylar iron

[DrPeper]

Well I guess I'll have to take another look at trying an iron.  There's certain logistical problems with an iron because ideally you just want a 1/4" seal in the middle so maybe I could put some kind of metal bar down then use the iron to heat the bar and provide pressure for the seal.

Thank you for your contribution!

[kill-a-watt]

one of the vids on youtube had someone using a cheap aluminium level as the "anvil" below the bag. I suppose something made of the same thing and not as wide would work. I've got some scrap 3/16 plate aluminium around but it's not exactly an everyday object.

[DrPeper]

I saw that video, but it didn't occur to be that I might be able to adapt it for this purpose until you brought it up in your comment.  I'm wondering if I might be able to use 1/2" copper piping, mostly because it's easy to get at the hardware store and I have some laying around that I could use.

[roadlet_411]

I actually work with machines that fill pouches very similar to this.  We fill them with a powder, not a liquid, but the method for sealing has to be the same.  All that seals the pouches is a heated surface not much different from your method, just a larger contact area to seal one entire side with each contact of the heater.  Depending on the general thickness of the stock, I seal bags in the range of 280*F to 310*F.  Heating long enough is just as important as heating too long or too hot.  You don't want delamination to occur at your seams, as this will cause the laminate to pull away from the foil and make a potentially weak and leaky seal.  Hope that's useful for you.

[DrPeper]

Yes!  Thank you for your contribution!  The soldering iron is tricky at best.  I tried welding 4 pouches together but one of them pulled apart from the the rest.  The other 3 were welded just fine.  I'll be updating my instructable in the next day or so.  I think the problem is pressure, so I'm thinking of using a bar to press down on the seal then using the soldering iron to heat the bar.  I think I'm back to making a bar welding clamp with some small pipes and some nichrome wire.  I also want to return back to the Eurosealer with more voltage, and I think I'll have to try the clothing iron per the comments from "kill-a-watt".

[Zaphod Beeblebrox]

join my group!

[CameronSS]

Umm...Spam much?

[Zaphod Beeblebrox]

well lok at his name just trying to get members............do u like dr. pepper?