Permatex

[Candybee]

I've been using the Surebonder brand of all purpose glue sticks for all temperatures. Once you glue a wick tab to the jar it sticks permanently. And I mean permanently! Its almost impossible to get it off. I have tried and only successfully got the wick unstuck after prying real hard with a knife and much sweat and swearing.

I got them at my local Ace hardware store.

[grama]

I use the multi-temp glue sticks from Wal Mart and have never had a problem with the wick coming loose. I put a good dollop on my wick tab and it is stuck!

[Candybee]

I use the multi-temp glue sticks from Wal Mart and have never had a problem with the wick coming loose. I put a good dollop on my wick tab and it is stuck!

Thats because the multi purpose also includes the high temps too. Plus once you apply the glue and stick your wick tab to the jar you can pour your candle immediately-- no waiting. I like that!

[lrbd]

Well just for the heck of it. The method I use does not require a waiting period and I have never had one wick come loose in over three years. I won't bother to tell it again but if you are interested....oh never mind.

you have me wondering......

[lrbd]

Nope. It sets up in an hour - two hours, max. :

Thanks Stella.... Were ya been?

[Candlebuddy]

I use 100% silicone ... DAP makes it, a tube costs about $3, you can pick it up at Home Depot (or Walmart). It takes about an hour or so to dry completely. I've never had a wick come loose, even when power burning.

[Stella1952]

The reason we use wick assemblies is twofold:

1. The stuck-down wicktab holds the wick in the center of the candle and keeps it there while the candle is poured and burned. The wick cannot fall over into the wax.

2. The wicktab causes the wick to self-extinguish when the fuel level goes below the top of the wicktab. When the wick cannot draw fuel from the sides or the bottom, it will extinguish because it has run out of fuel. This is important because, despite warning labels which direct customers to discontinue use when there is only 1/2" of wax in the bottom, many people ignore that instruction!

I think what is important here is that whatever adhesive you use, it needs to:

Not soften or release at high-end operating temps in container candles (tins OR glass). These can exceed 500°F, so make sure the adhesive you use is rated that high, regardless of whether you personally have experienced a wicktab loosening or leaking. The idea here is to protect our customers AND ourselves (product liability lawsuit!) from a wandering or leaking wicktab. One does not want the first time a wicktab turns loose to happen to a customer and start a home fire. *faint*

From what I have been reading, hot glues vary in their ability to remain hard at temps much above 200°F. When hot glue (or any adhesive) softens, it loses its holding strength.

Most hot melt adhesives solidify at temperatures below 180° F and become low viscosity fluids at temperatures above 180° F.

http://materials.globalspec.com/LearnMore/Materials_Chemicals/Adhesives/Hot_Melt_Adhesives

Because this glue does melt, it will soften well before it liquifies.

All it takes for a wicktab to fail is for the adhesive to soften, allowing liquid wax to be fed to the wick from underneath the wicktab until all the liquid fuel has been sucked up, allowing the container to become waaaay overheated.

Don't get me wrong - I LOVE easy!!! I would MUCH prefer to use stickums or hot glue. I think they're easier to apply and have a much shorter set-time than does silicone rubber. They're also a LOT easier to remove from used containers. Unfortunately, I HAVE had failures from stickums AND hot glue (See photo below), which is why I do not use stickums or hot glue for candles other than ones I am testing for wicking & hot throw. My customers get the foolproof silicone rubber stuff.

Note that the hot glue adhesive softened enough to allow the sustainer base (wicktab) to wander over to one side of this status jar. The movement begins because of heat convection currents in the liquid wax, the suction the wick creates when struggling to suck liquid wax and the fact that the bottom of the container is unlevel. The wick continues sucking up the liquid wax (see the clear area around the wicktab?) until it literally sucked dry before it ran out of fuel and extinguished! Note the ugly sooting on the side as a result of the wick becoming off center. The wick I tested in this jar was not too large for this container & wax - it is the correct size I use today; however, it became a torch because of the failure of the adhesive under the wicktab.

This photo is also a good argument for never selling candles in used containers. This container was cleaned after the photo was taken and is still one of my testing jars. Doesn't appear any different than the brand-new jars! However, it has been subjected to extremely high temps in excess of its specifications. It would be a good candidate for stress cracking.

Hey! I just thought of a really easy test to see if one's adhesive is suitable:

Get a tin and put a stickum or dollop of hot glue or high-temp silicone rubber sealant (or whatever you are using as an adhesive) in the middle of the bottom of the tin. Allow it to set up or cure or whatever for 24 hours. The next day, put the tin in the oven preheated to 500°F. Allow it to remain there for 15-20 minutes, then remove and poke the adhesive material with a skewer to see if it has softened or if you can move or remove it. If it softens or moves, it isn't suitable for candlemaking.

Think that would work?

[lrbd]

I know you are correct about the hot glue. I remove them myself all the time when testing . All I do is wait until there is 1/2 inch of liquid left and out it comes. No doub about it . That's why I picked up the Permatex. I am so glad I don't have to wait 24 hours though.

[charmcandleco]

I don't know if you have a hobby lobby around your area. But I found a product that is called Dimensional Silicone. It is awesome it is heat resistant, it also says its perfect for glass, and it has no odor at all. It says to wait 24 hours as well. But every time I have used it I only wait 1 to 2 hours and it sets up fine. Oh and the maker is Decorator's Solution. Another good thing about it is all you have to do to remove it is just scrap it with your nails then stick it in the dish washer.

Edited September 9, 2009 by charmcandleco

[ArizonaScents]

Permatex vs Silicone

This might actually solve a problem I have.

We use a very unique metal container with a diameter of about 2in for some of our candles and the issue I am having is that the containers are seamed along one side and the bottom and occassionally the seams aren't quite tight (sealed) and the seams weep (leak) a small amount of wax.

I've performed test burns and so far have not encountered any issues with the containers when actually burning them as long as I set them on a small plate or other surface; however I'm concerned that a customer might not follow the directions included with each container and I'll end up with a liability problem.

Is Permatex non-flammable or does is the burn temp high enough that the candle flame from a small diameter container will not ignite it? I've read that the flash point of silicone is 750c well above any temp a soy candle should get and it's fairy easy to apply.

Thanks in advance for any input.

Edited September 26, 2009 by ArizonaScents

[Stella1952]

First, let's all understand:

Permatex IS a silicone rubber sealant. Permatex is a brand name (like Dow-Corning or GE). The Permatex product line recommended was developed for use in making self-sealing gaskets for automotive engines. The temp range and specs were given by Chuck in post #3 of this thread for your review.

Please understand what "flash point" means:

The flash point of a flammable liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed.

http://en.wikipedia.org/wiki/Flash_point

The "flash point" you read about would have to be referring to silicone rubber in its LIQUID state, or the information is inaccurate. Solids don't have flash points. Silicone rubber changes form - from a liquid to a solid - due to a chemical reaction as it cures. It does not soften or return to its initial high viscosity liquid state the way hot glue does.

Silicone rubber sealants can be engineered for use in high temperature applications, but I do not know if the material is considered inflammable. Check the MSDS for the brand(s) you are considering.

The actual flash point of NatureWax C3 listed on its MSDS is "greater than 600°F." This value is different for each brand/formula of wax, so check the specific MSDS for YOUR wax.

You may want to verify the type of metal in your containers and seal the seams with a metal type sealant. If the material is tin, zinc, copper or brass, the seam can be resoldered.

Personally, I would try to find a container that is manufactured better, especially for use with candles. If it leaks and you have to spend time & materials repairing it, it isn't a well-made product to begin with and this means that the end product - your candles!- could not be considered well-manufactured either because of the faulty container.

[ArizonaScents]

Thanks for the input.

I've been trying to find an alternate provider but so far have been unsuccessful.

I failed to mention that this particular container is only made by special order and is usually used as decoration for special events (weddings etc) and it is not in any of our standard sales material - in part becuase of the issues stated above.