Replies

1. 
   forestgirl | Nov 10, 2004 09:52am | #1

   You talking about the basic hot-melt stuff that the little guns are for?  You can get those sticks at any craft or hardware store.  The high-temp would be what you'd use for this purpose (low-temp is for fabrics and paper, other light stuff).  'course you need a high-temp or dual-temp gun.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
   Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

1. 
   Manchild | Nov 10, 2004 05:21pm | #2

   Forestgirl, Thanks for the heads up. I have a low temp gun I think. My wife and kids use it for crafts around the house.

   Polyethylene is the softer slippery plastic they make some water bottles out of. It's never clear but sometimes they make them frosty so you can see the liquid in them.

   I need the right glue stick or it won't work. What are the sticks at the hardware store made of? I understand that I need high temp glue. Beyond that it's a mystery??????

   I'll go to the hardware store today and see what they have. The problem I have is that they aren't specific at the consumer level. The package won't say it's for polyethylene. It won't even say what the glue sticks are made of. Just be a good consumer and buy it on faith I guess.

   I went back and the description is for Tuf-Tac high performance glue sticks and price shipped is $ 49. I have one bottle to do at this time.

   I e-mailed them again with my concerns. I'll look around some more for info and smaller quantities.

   Edited 11/10/2004 9:33 am ET by david

2. 
   JohnWW | Nov 10, 2004 05:54pm | #3

   Polyethylene plastic is just about impossible to glue, that's why they make glue bottles out of it.  In manufacturing, poly components that have to be joined are welded together by melting. 

   You may be able to find some exotic glue that will bond at least weakly with poly, but I'm not aware of any hot melt that will form a good bond.

   John W.

1. 
   Manchild | Nov 10, 2004 07:15pm | #4

   Hi John, How hot do you think it would have to be in order to be considered welded? Do you think perhaps that a high temp glue gun could achieve those temps?

   Say a glue stick was made out of polyethylene, was melted into a liquid, and applied to a polyethylene substate. Would that be considered welding?

1. 
   JohnWW | Nov 10, 2004 08:11pm | #5

   I doubt that the hot melt glues get up to the temperature needed to melt polyethylene.  The few times I've tack welded poly I've used a soldering iron that probably runs a couple of hundred degrees hotter than a hot melt gun.

   The simplest way to test the temperature of hot melt would be to just run an experiment with a standard adhesive in the gun.  Allow the gun enough time to reach full temperature, then waste a little bit of the glue in the gun's tip to make sure you are getting the hottest glue from further back in the gun, and run a bead of glue on a piece of poly.  Once the glue has cooled try to peel it off.  If the glue truly bonded, the bead should be hard to remove and leave a scar on the surface of the plastic.

   John W.

    

1. 
   Manchild | Nov 10, 2004 08:51pm | #6

   Thanks John! That's an excelent idea. I was thinking that since it is a bead I'm after, I could lay the tip of the gun on the substrate while the bead comes out of the nozzle so the bead would be laid on melted plastic.

   I think it is time to get busy and try it.

1. 
   Len | Nov 10, 2004 09:05pm | #7

   There are a number of different types of hot melt adhesives available. And your right it's not regularly available to consumers.

   I use a 3M gun and have tried almost all the types at one time or another. Check http://tinyurl.com/3ksjk It will give you a good list on what's available.

   Gluing polyethylene is tough. I have had success with this product. http://tinyurl.com/6mkhp

   Hope this helps.Hi, I'm Len and I'm a Toolaholic...

2. 
   BenM | Nov 10, 2004 09:07pm | #8

   What are you trying to accomplish?  Maybe there is another way to do it.  I don't think there is a glue that will work.

3. 
   Manchild | Nov 11, 2004 12:19am | #9

   If I tell I'm afraid I will get ridiculed. It's best not to broach the subject. Let's just say I have hoby that is way overboard by most peoples standards.

   I can tell you I'm trying to put a small bead around a water bottle. Here's a pic of my first attempt. I cut a band from another bottle, ground a groove in it where the band sits, and used thin double sided tape under it.

   
4. 
   BenM | Nov 11, 2004 03:58pm | #10

     I'm afraid I will get ridiculed.

   It can't be more ridiculous than woodworking where one buys $5,000 worth of equipment to build $500 worth of furniture. :)

   It looks like you want to attach the bottle to a bike frame? Or something like it?  Maybe you can just use a cable tie (the plastic thingee to secure wires etc) around the bottle. Or how about a thick, hefty rubber band?

   Edited 11/11/2004 8:09 am ET by BenM

2. 
   AlbionWood | Nov 11, 2004 08:34pm | #11

   High-density polyethylene (HDPE) is usually fusion-welded at around 400 F. I think HDPE bead-welding guns run a little hotter than that. Low-density PE might be welded at lower temps, I'm not as familiar with that stuff.

   To get a good bond, both the substrate and the glue need to be near the melting temperature, so the molecules will crosslink. If the substrate is cold, then the bond will be poor or nonexistent. You can use a high-temp glue gun and use the nozzle to preheat the substrate as you lay down the bead."Everything should be made as simple as possible, but no simpler."  A. Einstein

   http://www.albionworks.net

1. 
   Manchild | Nov 11, 2004 09:13pm | #12

   Thanks for the info everybody. As usual you came through with flying colors.

   I have a cheap gun that might get the job done. I'm going to put the tip of my cheap soldering gun behind the tip of the glue gun to up the temp of the glue and nozzle. hopefully this will get the job done.

   I went to the hardware store and they had dual temp sticks. I bought a couple.

   Now to find my glasses?????

3. 
   OneofmanyBobs | Nov 12, 2004 08:56pm | #13

   There are special (and fairly expensive) flexible cyanoacrylates that will bond to poly.  Most everything else will not.  The super glue is about $10 for a tenth of an ounce if you can find it.  Last stuff I found was black.  Melting it will bond it to another piece of poly.   Might be the best way.  A soldering iron will work if you're careful.  Not very pretty, though.  There are special "welding" tools for poly.  I don't think hot glue will do it.  Maybe a PUR (polyurethane reactive) hotmelt would.  Not a consumer item.  Special gun.  Expensive.