Desiccant bags for telescope, accessories etc

[Saturn488]

Any particular dessicant bag recommended to use or can I just buy a bulk pack off eBay?

Looking to put some in my telescope bag, camera cases, eyepieces, etc.

Thanks!

[Dave221 (David)]

I use these, they are able to be re-charged many times in the oven. They are a little pricey though.
‘Hydrosorbent Silica Gel Dehumidifier 40 grams’,
https://www.silicagel.com.au/categor...Dehumidifiers/

[RAJAH235]

Hi Chrys,
Just an idea here but many years ago I went looking for Silica Gel for my telescope & eye pieces.
Luckily, I worked for a Co. that serviced photo copiers, faxes & other office M/C's.
The crate/s that they were packed in all contained 1/2 lb packets of Silica Gel.
I grabbed quite a few of them, so maybe check out a Photo Copier Service/Business Machine shop or 2?.

The other place you may get smaller packets from is any shoe store.
Most, if not all shoes have a few packets of Silica Gel in each box.
Ask them nicely to save you some & you may end up with more than you require......eg; A shoe box full.

HTH.

[mental4astro (Alexander)]

Dave put me onto the stuff he suggested - blooming brilliant!

Can be used in many ways, in the scope case and inside the cap/lens cover by making a soft cotton bag with a Velcro opening so the saturated desiccant can be removed and recharged.

Alex.

[Saturn488]

I might get a few of those for my telescope bag and camera case but for my eyepiece and accessories something like this might do the trick.

https://rover.ebay.com/rover/0/0/0?m...2F312243017450

[Huey (Michael)]

Hello there,
have a look at this site :

http://www.silicagel.com.au/1-kg-blu...lf-indicating/.

They sell 500g for $19.50 and it is self indicating.
It changes from blue to pink when it needs to be reconstitute. This can be done in a microwave.

Hope this helps

Huey

[Stonius (Markus)]

Originally Posted by Huey

.
It changes from blue to pink when it needs to be reconstitute. This can be done in a microwave.

This needs to be done gently or else you end up with silica popcorn.

Use medium for a few minutes and check the colour. If using a standard oven, I believe about 130 Deg C is about right.

Others may chime in with their own recommendations, but what I'm saying is don;t blast it on high for 10 minutes, or stick it in an oven at 180, if you get my drift :-)

Markus

[Wavytone]

One thing to note - that supplier despatches via couriers - not Australia Post - which for me is basically a no-go.

[sharpiel]

Doesn’t Bintel sell the self indicating stuff? Sure I bought some there previously...

[Kaffine (Craig)]

Any bags should do, I use the ones I get in work merchandising kits, If you don't want to buy them go into any electronic store JB's, Harveys etc and ask there they may have some laying around from TV's etc.

Oh and if you put them in your scope to stop lens fungus don't forget to remove them before imaging. Don't ask how I know

[fornax (Phil)]

Originally Posted by sharpiel

Doesn’t Bintel sell the self indicating stuff? Sure I bought some there previously...

yes, the Farpoint Dessicant cap uses self-indicating silica gel packs. When I went to replace mine, ALL of the replacement bags were pink! Even though they were stored in airtight containers. I cut them open and put them in an small foil tray and baked them in the oven for 15 minutes and the gel turned dark blue. Then placed the whole lot in a small cotton bag and reused them that way.

[mental4astro (Alexander)]

DIY is another option. Same job, same desiccant, fraction of the cost.

Found a suitable plastic jar at a $2 shop (had glitter in it). Made holes in its bottom. Perforated a self-locking plastic bag and filled it with the desiccant - got the desiccant from Ebay, very inexpensive for 1/2kg or 1kg. Closed jar and popped into the back of the scope. Made several of these to fit in my various scopes and a few that sit in scope cases. All up cost me less than one single FarPoint plug for ALL my scopes and cases!

The last pic shows the indicating silica gel, blue being all ready to go, pink saturated with water. Easy to recharge in an oven.

[AstralTraveller (David)]

The blue/pink desiccant is supposedly banned in Aust because the indicator CoCl2 is considered carcinogenic. We got rid of it all over a decade ago. The orange stuff is what you want. I think it might go clear or perhaps green when it is wet. I never let it get worse than light orange so I've forgotten the end point. As it happens I've just re-dried a pile of it for some big desiccators that someone wants to use next week.


Note too that this type of desiccant 'only' removes moisture down to about 40% relative humidity. If you want really dry you need a chemical absorbent, maybe something like MgCl2. However, that is overkill and there are too many practical issues.

[Chapstick]

Thanks for the information - Im just about to buy some to refill my Farpoint caps.