Gamma Lids

[cmxterra]

Just a heads up to anyone using lids made by #Gamma2inc that they seem to be prone to failure. Mine were kept in a temp controlled environment and not subjected to any heavy loads on them and they cracked right down the middle ruining the air sensitive stuff in them.

So if you are needing something air tight and to last longer than a year you might want to search elsewhere.

[Morning Sunshine]

weird.  I have had 2 fail in the 13 years I have had the 20 or so on my buckets.  I even have some of them stacked - very carefully with the 13-lb egg noodles or quick oats on top if it is a double stack of Gamma lids.

The first one was on a bucket I use in my kitchen, and my kids were always using it as a stool to reach the counter, so I was not surprised at that one.
The second was a bucket my son took outside and did - I have no idea what he did to that bucket, but he was a 13-yo boy with a plan, so I am also not surprised by that one.

I am not discounting your experience, I hope you know that and I am glad for the warning.

[mountainmoma]

Sorry to hear you had troubles. 

I also have been using these for years,  and the only times I have had breakage is from children standing on them, or stacking 3 high with heavy contents, and then it doesnt break in that area.

But, just a heads up, nothing in a plastic bucket with a lid is totally air tight.  You would need a mylar barrier in addition to be air tight.  There will always be a slow air exchange in the buckets.  SO, not for 20 years, but good for a couple years

[Redman]

Perhaps there has been some change in the plastic formulation. Those lids appear to have GAMMA PLASTICS COMPANY   SAN DIEGO, CA. on them as do mine. I don't remember if they had Gamma2 on the label.

I have a question though. Are all the cracked lids colors other than black. Mine are black and only about 3 years in use but it's a thought and very limited experience with plastics years ago make me think some colors of these lids may not perform as well as other colors, that is just conjecture. Also those cracked lids look thin, I don't know how thick they should be but they seem thin to me. Also they have an odd look like the flat surfaces may not be all flat. Some of that look may be caused by lighting but not all I think.

[cmxterra]

I have my speculation that it is a color problem. I have some white ones that are fine and all the colored (red and blue) ones have failed.  I contacted them and they are not concerned about replacing them since they are over a year old.

I too have seen them fail if you stand heavy things one them and this is nothing like that. I had these buckets stored away from climbing kids and had we not been doing some housekeeping I would not have discovered them.

[Redman]

It would be interesting to find out if there have been failures of white or black lids. BTW my buckets are not stacked but one of the has had a large bag of baking soda sitting on it for a couple years.

[fritz_monroe]

Sorry to hear that you've had issues.  I only have a half dozen or so in use.  I've kept 2 of them out in the carport for the past 2 years.  I also have several down in the controlled environment of the basement.  I don't stack more than 2 high.  Luckily I haven't had any failures.

The carport lids are black, I have a couple white ones, a yellow and an orange. 

[Stwood]

I've had one orange failure. It was the rim part, not the lid.
Cracked down the side after I got it on.
Contacted the amazon seller directly, and they said they've had a orange color problem. Cracking where they attack to the mold, a thin spot.
They replaced the rim only.

[Redman]

Looks like that's where cmx's lids are cracking, at the mold sprue attachment. Yeah they could possibly be thin there. Depends on how the break off.

[Morning Sunshine]

slightly related, but a tangent....

what does the color of the plastic have to do with the strength?  Does the dye weaken the material in some weird chemical reaction?

[Redman]

Apparently so. My limited experience also indicates to me that the Gamma lids and rings may be injection molded. I'm not at all experienced in other molding methods. A short article on an apparently complex subject.

https://www.manufacturingtomorrow.com/article/2018/05/how-colorants-affect-plastic-characteristics/11518/

[Stwood]

Wonder if it's also the mold. You know, run only all orange thru one, black through another.

My amazon seller (can't remember the name) said the sprue area was where they were cracking on their batch, and mainly orange.

[Redman]

Dedicated molds would be pretty expensive. I think if a problem in the sprue area related to thickness was identified that area would be easy to correct. Just looked at one of my black lids and it has a tit on the inside opposite the sprue. Also I see 5 places that look like they could be the knock-outs for the mold, one is in the center opposite the sprue so that would be an easy place to increase thickness. Just machine a concavity in the end of the knock-out pin and that seems to be what was done. I haven't looked at my rings close enough to determine whether the 4 equally space spots I see are sprue connections or knock-out impressions.