Metal cutting - oxyfuel cutting, plasma cutting, machining, grinding, and other preparatory work.
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Just received this today. Hoping it's all it's cracked up to be. Supposed to obviously help consumable life, but also maximize cutting power, as humid air robs the arc of available energy that would otherwise be directed into the material being cut.

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tweake
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big thing with that setup is you will probably "use up" the desiccant quite fast.
i highly recommend getting the air as dry as you can before it gets to that setup which will extend the "life" of the desiccant.
tweak it until it breaks
sbaker56
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I'm curious if you notice any improvement in cut quality, which I often hear mentioned as one of the benefits to having air dry as possible, post cut grinding sucks and the cost of abrasives add up over time too.
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Yea, my air supply runs through two of these (in parallel)

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...to remove as much moisture as possible. Also the air line is 100ft of quadruple 1/2" hoses from my air compressor into the garage, so the air does get to cool a good amount before it even gets to those parallel filters. I've never seen so much as the slightest condensation at the small filter/separator that comes stock at the back of the plasma cutter. So the air should be pretty dry before it even gets to this new dryer.
sbaker56 wrote:I'm curious if you notice any improvement in cut quality, which I often hear mentioned as one of the benefits to having air dry as possible, post cut grinding sucks and the cost of abrasives add up over time too.
I'm definitely counting on it.
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tweake
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Oscar wrote:Yea, my air supply runs through two of these (in parallel)

...to remove as much moisture as possible. Also the air line is 100ft of quadruple 1/2" hoses from my air compressor into the garage, so the air does get to cool a good amount before it even gets to those parallel filters. I've never seen so much as the slightest condensation at the small filter/separator that comes stock at the back of the plasma cutter. So the air should be pretty dry before it even gets to this new dryer.
sorry to bust your balls a bit here,
but the compressed air is still 100% full of moisture. this is something that most people do not get their head around. moisture is a gas while water is a liquid. the traps/filter catch water, not moisture. moisture goes straight through.
you need something to turn the moisture into water or something that can actually catch moisture.

the most common ways is to use a refrigerated drier. but even then that only gets it down to 2c/35f dew point at best.
a desiccant drier will get it down to around -30 dew point.
there is a few other methods but they are rare for home use.

the catch with desiccant is having to swap out for a new lot and recharge the old lot.
my cheap version would be lucky to last a day with all out usage. it didn't take long before i had to change it out.
yours is a big bigger so i expect a bit longer run time, but i suspect you would do more cutting than i ever do.
this is why you really want something like a refrigerated drier before the desiccant.
tweak it until it breaks
BugHunter
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Typically you can bake the desiccant in the oven and re juvenate it.

Refrigerated setups are really the ticket but they cost more than a compressor and they cost more to run than a compressor. You have to really have a need for dry air to justify the cost because they are not cheap. At least not for the amount of air I use at work.
tweake
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BugHunter wrote:Typically you can bake the desiccant in the oven and re juvenate it.

Refrigerated setups are really the ticket but they cost more than a compressor and they cost more to run than a compressor. You have to really have a need for dry air to justify the cost because they are not cheap. At least not for the amount of air I use at work.
yes you bake it to rejuvenate it. tho leaving it in a hot place for a long time seams to work well to (eg hot water cupboard).
it just takes time to do.

usa usually has some cheap refrigerated driers, tho some are crap. usually not worth more than a compressor if its commercial. certain can be expensive if you have a small hobby compressor.
they certainly do not cost more to run. they are really low powered compared to a compressor.
i think at work i was looking at a 1/4hp drier which would handle up to a 10 hp compressor. drier is worth about a 1/3 of what the compressor is worth (and its a cheap commercial compressor).
if its costing more to run than the compressor, something is very very wrong with the setup.
tweak it until it breaks
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tweake wrote:
Oscar wrote:Yea, my air supply runs through two of these (in parallel)

...to remove as much moisture as possible. Also the air line is 100ft of quadruple 1/2" hoses from my air compressor into the garage, so the air does get to cool a good amount before it even gets to those parallel filters. I've never seen so much as the slightest condensation at the small filter/separator that comes stock at the back of the plasma cutter. So the air should be pretty dry before it even gets to this new dryer.
sorry to bust your balls a bit here,
but the compressed air is still 100% full of moisture. this is something that most people do not get their head around. moisture is a gas while water is a liquid. the traps/filter catch water, not moisture. moisture goes straight through.
you need something to turn the moisture into water or something that can actually catch moisture.

the most common ways is to use a refrigerated drier. but even then that only gets it down to 2c/35f dew point at best.
a desiccant drier will get it down to around -30 dew point.
there is a few other methods but they are rare for home use.

the catch with desiccant is having to swap out for a new lot and recharge the old lot.
my cheap version would be lucky to last a day with all out usage. it didn't take long before i had to change it out.
yours is a big bigger so i expect a bit longer run time, but i suspect you would do more cutting than i ever do.
this is why you really want something like a refrigerated drier before the desiccant.
Yea, you're right, I was being overly optimistic. :D. The way I see it, It can't be worse than before when I didn't have it. Previously I had thought about making a ginormous desiccant tank out of some 6" sch40 pipe, but I'm not sure how to properly channel the internal volume so the air doesn't take a straight shot to the exit and not make it's way through the actual desiccant.
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Poland308
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Large commercial ones have the air coming in the bottom, and then there is just perforated screen that keeps the media from coming out top or bottom. There’s enough room between the screens that the media has room to move. It relies on the fluid effect that , grains of desiccant take on when air is flowing through them. I’ve cut open a big one that came off of a medical air setup so I could see what they were doing. The theory was actually discussed in a mythbusters about quick sand.

They also do something very similar inside large coal fired boilers. The bottom is lined with sand and air is blown up through the sand. It keeps the bottom of the boiler from melting. And the burning coal more or less floats on top.
I have more questions than answers

Josh
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I see. I do have some 6" pipe but I'd need some heavy duty caps as the only ones I have are sch 10 I think, about 1/8" thick. I'd probably also need some large NPT plugs to make the inlets/outlets out of. Or I'm just over thinking it altogether and this dryer will work fine for a good long time.
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Poland308
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Sch 10 is enough for 150 psi steam.
I have more questions than answers

Josh
tweake
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Poland308 wrote:Large commercial ones have the air coming in the bottom,......... .
even with the cheap ones the incoming air goes down a pipe in the centre of the unit to the bottom and air flow up through the desiccant.

large commercial ones run a bit different and often use purge air and/or heaters to dry the media. their pipe layout is a bit more complex.
tweak it until it breaks
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I see. Let's see how this system works as-is. I have some scrap from previous trial-and-error that I should cut up to throw away. If I find the desiccant starting to change color then that will be indicative that it is indeed catching a good amount of moisture.
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tweake
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Oscar wrote:I see. I do have some 6" pipe but I'd need some heavy duty caps as the only ones I have are sch 10 I think, about 1/8" thick. I'd probably also need some large NPT plugs to make the inlets/outlets out of. Or I'm just over thinking it altogether and this dryer will work fine for a good long time.
over thinking it.
the dryer will work fine apart from probably saturating the desiccant fairly quickly depending on use.

some setups i've seen use 20" long units that take big quick change bags of desiccant.

if you want to get fancy, if your using the drier for air tools as well, fit a dry tank after the drier. just a small storage tank. driers work better with constant air flow rather than on/off pulses.
tweak it until it breaks
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No this is plumbed right before the plasma cutter, I won't be using it for air tools what so ever. Let's see how this pans out. Like I said, it will surely be better for the plasma cutter than before when it wasn't there.
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tweake
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Oscar wrote:No this is plumbed right before the plasma cutter, I won't be using it for air tools what so ever. Let's see how this pans out. Like I said, it will surely be better for the plasma cutter than before when it wasn't there.
cool, see how it goes.
see if it drives you nuts swapping desiccant out.
tweak it until it breaks
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