Silica Gel Packs for Moisture

The little ones supplied with lenses etc don't have much capacity to absorb water & fall apart if you try regenerating them. You can get larger packs that can be stuck in an ordinary oven at 120°C to dry them out.

I got mine from work brought for an instrument we no longer use - but I'm sure others can be found on the likes of Amazon. Just make sure you get regenerative desiccant.

YnotMe wrote:

Thank-you. They seem to be sold/advertised in grams, 3, 5, 10. What size would be sufficient if still putting in different pockets throughout my bag?

It depends on where you are, how big the bag/pocket is, how well sealed it is & how often you regenerate.

I think the packs I have hold 25g.

I've always steered clear of making my own packs _ they'd need to have free circulation of air but hold in the silica. Despite it's name Silica gel is a hard grainy material that could scratch lenses. We have a wide variety of mesh sizes at work ranging from about 5mm to fine dust.

petrochemist wrote:

YnotMe wrote:

Thank-you. They seem to be sold/advertised in grams, 3, 5, 10. What size would be sufficient if still putting in different pockets throughout my bag?

It depends on where you are, how big the bag/pocket is, how well sealed it is & how often you regenerate.

I think the packs I have hold 25g.

I've always steered clear of making my own packs _ they'd need to have free circulation of air but hold in the silica. Despite it's name Silica gel is a hard grainy material that could scratch lenses. We have a wide variety of mesh sizes at work ranging from about 5mm to fine dust.

I did make my own pack from a piece of strong fabric on the sewing machine of my wife. A strip of velcro to close the bag. It holds a paper-like bag with 60 gram silica gel. It is not real paper and it gets wet while regenerating (at 120 C in the kitchen oven) but does not fall apart. But it feels fragile and when it rips you have the silicagel all over your equipment. So thats why i made a stronger bag.

On the photo you see the silicagel bag at the right and the self made bag at the left. The silica bag only gets out when it is time for regenerating.

zoeker wrote:

petrochemist wrote:

YnotMe wrote:

Thank-you. They seem to be sold/advertised in grams, 3, 5, 10. What size would be sufficient if still putting in different pockets throughout my bag?

It depends on where you are, how big the bag/pocket is, how well sealed it is & how often you regenerate.

I think the packs I have hold 25g.

I've always steered clear of making my own packs _ they'd need to have free circulation of air but hold in the silica. Despite it's name Silica gel is a hard grainy material that could scratch lenses. We have a wide variety of mesh sizes at work ranging from about 5mm to fine dust.

I did make my own pack from a piece of strong fabric on the sewing machine of my wife. A strip of velcro to close the bag. It holds a paper-like bag with 60 gram silica gel. It is not real paper and it gets wet while regenerating (at 120 C in the kitchen oven) but does not fall apart. But it feels fragile and when it rips you have the silicagel all over your equipment. So thats why i made a stronger bag.

On the photo you see the silicagel bag at the right and the self made bag at the left. The silica bag only gets out when it is time for regenerating.

Looks good.

The packs I have are in metal canisters so could scratch paintwork etc. if I get careless. I guess fabric bags would be a better option.

Is there a way to recycle the bags you get with new gear? I would prefer not tossing them in the landfill.

HRC2016 wrote:

Is there a way to recycle the bags you get with new gear? I would prefer not tossing them in the landfill.

You can dry them out if you have a vacuum oven, but I'd rather doubt you do. The one in our lab cost over £1000, without the vacuum pump...

I suppose you could cut them open & repackage them in sown fabric, of perhaps just sow the seams of the packages as they are - so you can heat them to about 120C in a normal oven, but I suspect the amount of silica gel in them isn't enough to be worth the effort. The usual packs only have 1 - 2 g in them which would get saturated very quickly in anything you open often.

The contents are a silicon oxide not dissimilar to sand. Water insoluble & fairly unreactive. AFAIK the only hazard is a s a fine powder in the air where it can cause silicosis if breathed in..

I have used Silica Gel for cats. 5 kg  bag is cheap and lasts looong...