Cheap hack compressed air dryer

[rcx132]

Ok so it was user Awemawson's idea (on this forum) to use a water filter as housing to make a desiccant compressed air dryer, which he then modified.

But actually you can save yourself the trouble of modifying the housing, by installing a refillable cartridge, that you can fill with the desiccant.

Refillable universal 10" cartirifges, £8 on ebay, can be filled with anything:

They fit into a standard 10" water filter housing:

Further savings can be made by tearing apart nappies instead of buying silica gel

The units say they go upto 100 - 125psi but burst pressure is 360 psi. Can be bought with 1/4" or 1/2" or 3/4" ports.

Just ordered the whole things on Amazon for £25. And the silica gel is going for £5/kg at the moment on Amazon.

 

[Seadog]

I don't know which Amazon you're using, but my Amazon is £6-49/500g

 

[rcx132]

I don't know which Amazon you're using, but my Amazon is £6-49/500g

£11 delivered for 2kg and you get a pair of scuba diving balast bags for free
https://www.amazon.co.uk/gp/product/B00AZZB5UY/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

 

[Seadog]

OK, but it's not indicating silica gel is it? And the total weight does include the bags...

 

[Crater Creator]

It's not colour changing type, but if you've got a pets@home store nearby, you can get silica gel granules here:
http://www.petsathome.com/shop/en/pets/silica-gel-non-clumping-cat-litter--38ltr
3.8 litres for under a fiver but I don't know what that is in kilograms.
I use some in a cotton bag inside the MIG cover over winter to stop the wire corroding. I seem to remember I got the idea from someone on here.

 

[rcx132]

OK, but it's not indicating silica gel is it? And the total weight does include the bags...

You may be right on both counts. It does say "indicating" but on closer read it looks like it uses some other method to indicate when it's used up.

 

[optima21]

wonder if the silica crystals will work less efficiently if you use a refillable cartridge, as the air will be travelling much faster though the cartridge than if you use the housing on its own. the moisture can only be absorbed if it is in contact with the crystals, so if the air is moving slower, it spends more time in contact with the silica crystals, so more moisture will be absorbed.

 

[rcx132]

wonder if the silica crystals will work less efficiently if you use a refillable cartridge, as the air will be travelling much faster though the cartridge than if you use the housing on its own. the moisture can only be absorbed if it is in contact with the crystals, so if the air is moving slower, it spends more time in contact with the silica crystals, so more moisture will be absorbed.

The cartridge is still 10" long so it's got a fair but of silica to get through. There's also 20" versions available but the 20" cardridges don't come in a clear version.

 

[Maker]

You may be right on both counts. It does say "indicating" but on closer read it looks like it uses some other method to indicate when it's used up.

You could mix it up with a handfull of indicating crystals.

 

[optima21]

on my dryer using a water filter, you can see the crystals change colour, it starts at the top and goes down the filter housing and there is a distinct line between dry and wet crystals. the moisture does not appear to be distributed throughout the filter housing

 

[rcx132]

You could mix it up with a handfull of indicating crystals.

Top idea ツ

 

[rcx132]

That cheap Amazon desiccant has arrived and is, erm, cheap... it's 10% indicator beads and remainder is the clear stuff. I took some aside to test it in water, the 90% non indicator beads turned to mush.