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Darthwader
06-19-2009, 08:56
What's the hazzards connected with home fill stations? I originally thought that all I needed to worry about was keeping the filter current, but after a little more reading I realized that there may be other issues (thanks to Gene's Post).
If I can pull this off, I think that the convinience will far out weigh the cost factor (I figure that this thing will never pay for itrself)

Recon
06-19-2009, 09:01
I was looking in to it, and thought about getting one of the "cheaper" models, you know the one, around 3k dollars. then I figured.. $3,000 / $5 per fill = 600 fills... so basically, it would take me about 4 years worth of diving to pay that off. Unless my wife starts diving, then it will be a different story, cause that would give me MORE dive time and I would have another diver to supply.

~Recon

Darthwader
06-19-2009, 09:10
I was looking in to it, and thought about getting one of the "cheaper" models, you know the one, around 3k dollars. then I figured.. $3,000 / $5 per fill = 600 fills... so basically, it would take me about 4 years worth of diving to pay that off. Unless my wife starts diving, then it will be a different story, cause that would give me MORE dive time and I would have another diver to supply.

~Recon
that's about the price I was looking at. and I talked myself out it because of the cost factor. However, My LDS is closed so my nearest rentals/fills have are now about an hour's drive away!
Now I'm more than willing to eat the cost in favor of the convinience

skdvr
06-19-2009, 10:05
Dont forget about yearly maintenance/upkeep, and bank tanks if you want banks. The cost will be high but if it is worth to you then do it...

Phil

navyhmc
06-19-2009, 11:09
Also consider the increase in your electirc bills if you hook it up to your meter. Depending on usage, it will increase your electric bill by about 10%. If you get a gas powered model, keep a close eye on your filters to ensure your CO levels stay low.

fire diver
06-19-2009, 11:17
Depending on the model, you need to keep the costs of synthetic oil in mind along with the costs of filter changes twice a year.

You need to consider things like moisture seperators between the stages and whether or not it has automated dumps. If not auto, you will have to manually open the dumps every 10-15 minutes. You have to keep an eye on compressor temp too. If you have oil model, it can creat it's own CO if it gets too hot.

ColdPass
06-19-2009, 11:28
Have you considered buying about 10 more tanks instead? Then just take your truck load of tanks down to your not-quite-local dive shop and be set up for a month or so. You might want to run the cost-benefit analysis just to see if it's an option.

navyhmc
06-19-2009, 11:33
Have you considered buying about 10 more tanks instead? Then just take your truck load of tanks down to your not-quite-local dive shop and be set up for a month or so. You might want to run the cost-benefit analysis just to see if it's an option.

But that has the added cost of the annual inspections @$20-$40 per year plus the pentannual (is that a real word) Hydro's @$40-$60 per test. Can get pricey fast. Not to mention the original cost of the tanks themselves.

But you know, when you get right down to it, no one ever got into diving to save money. It's all about the dives and they are going to cost no matter what, The convience of having your own compressor does have an appeal all to itself.:smiley20:

in_cavediver
06-19-2009, 11:58
I joined the volunteer fire dept and now have access to thier air for free. Then again, it has costs too.

Still, HP air isn't cheap no matter how you slice it. We have 19 tanks in our stable and I'd hate to think about filling those from a slow $3k compressor. Still, I'd like to one day have my own fill station with banks to handle nitrox/trimix. I figure its 5-6k for a 'middling' compressor with auto drains and larger filters + the cost of the bank tanks, manifolds, hoses and meters. Figure 10-12k all said and done with me making a lot of the parts.

That brings me back to how nice it is I am on the VFD and the township pays for the compressor/maintence/banks etc.

navyhmc
06-19-2009, 12:09
In_cavediver: You are THE man!!!

I can actually get fills from our local fire deptartment. They don't mind the 80's, but hate my doubles.

WaScubaDude
06-19-2009, 12:28
snip..
Still, HP air isn't cheap no matter how you slice it. We have 19 tanks in our stable and I'd hate to think about filling those from a slow $3k compressor. Still, I'd like to one day have my own fill station with banks to handle nitrox/trimix. I figure its 5-6k for a 'middling' compressor with auto drains and larger filters + the cost of the bank tanks, manifolds, hoses and meters. Figure 10-12k all said and done with me making a lot of the parts.
snip...

Have seen a few fill set ups from shops going out of business here as well as a couple nice looking fill set ups on CL. The asking prices seem high but in this economic climate, if you have cash I am sure it would speak loudly.

Maybe a fill co-op? Or time share fill station? lol

CompuDude
06-19-2009, 13:48
I suspect with VERY careful buying a pretty decent setup could be had for $4-5k, but it's far from hassle free.

I think about every once in a while, but $4k will buy a LOT of tanks, and a LOT of gas for trips back and forth, and keep them vis'd and hydro'd for some time as well. I'm not so sure it's actually less work to run your own fill station.

I'm just thankful I have many choices of places to get my tanks filled so it's not an issue for me! (Including some friends who have their own trimix fill station I can use anytime, just kick in for helium costs)

baywatch106
06-19-2009, 22:04
I would love to own a compressor. No more bringing tanks to the LDS to get filled and 3 days later you go to pick them up and they aren't even filled yet.

Recon
06-19-2009, 22:26
For me ST, is close to an hour drive, depending on traffic at that time of day could be more like 1.5 hours +. Once there, an air fill cost 5 bucks, and takes like 10 to 15 mins, which is a guess, as I am almost ALWAYS browsing for more stuff to buy so... could be less. So all in all, a fill station in my garage, would be fan-freaking-tastic, but I can not justify the cost, maybe if there was a warm body of water with a thermocline above 21 feet close to me, and I was diving 4 to 5 times per month, 3 dives or so per day... then yeah... but right now... unless I move back to clearwater, fl (which, I very greatly dislike florida for various reasons), I do not see me buying a compressor.

~Recon

CWSWine
06-19-2009, 22:34
We just put this one together in May 09 and run us about $6500.00. Takes about 40 minutes per stage bottle to bring it from 2500 psi to 4500 psi. Not a high volume but fits our needs...

http://forum.scubatoys.com/gallery/files/5/6/2/8/compressor.jpg

navyhmc
06-20-2009, 00:28
Sweet Dennis!!!

Wish I lived closer. Is that the shop in topeka?

Recon
06-20-2009, 00:33
I wish that was the shop in my garage lol

~Recon

WaScubaDude
06-20-2009, 10:57
Did you win the lotto?
Very nice set up.:smiley20::smiley20: That's two thumbs up.

scubajane
06-20-2009, 13:18
I know that diving will always empty my wallet. I know that an hour drive to get tanks filled is long. I like the idea of being self sufficient. I know that there are only so many hours in a day sooo i try to prioritize.
do I have the space to set up a SAFE fill station?? yes but first I have to get rid of other "stuff'.
do I have the time to invest in the care of a fill station?? yes and no...
when I count up the amount of time, electricity, supplies, repairs etc is it really what I want to do??
I like to keep contact with my lds and tank fills are a good way to keep in touch.

jbres1
06-20-2009, 14:27
A home fill station is a nice thing to have, but don't expect it to be cheap.
I have a small compressor , and a 6 bottle cascade system that holds 2,200 cu ft of air. This is more than enough for my needs, and cost alot more than I figured it would when I first started.
I like having my system for the normal reasons,
1) no need to go to the LDS that is a 30 min. drive to get fills.
2) no waiting in line or going back to get the tanks when full. And no hot fills that cool down and drop pressure.
3) can top off tanks rather than doing a short dive.
4) can be sure of the quality of the air. I know when the filter and oil was changed last.
5) can blend what ever nitrox I want.
6) Cheap nitrox fills vs. the dive shop.

Things I don't like about the fill system
1) Time and cost to set it up , lets just say its more than $5,000.00. You could have alot of tanks for that money.
2) space it takes up.
3) changing oil and filters.
4)need to be around when the compressor is running to drain down the water in the system.
5) cost of power to run the compressor.
6) annual cost of filters and oil. I change my main filter in the spring a oil and filter on the compressor every 25 hours of run time.

When it is all balanced out, a home compressor is nice to have. But don't do it to save money, do it because it saves you time and its something you enjoy having.

Jim Breslin

navyhmc
06-20-2009, 15:24
Which is why we dive to begin with. To have fun.

Darthwader
06-21-2009, 08:45
For me, the whole argument comes down to convinience. is a home fill station a bane or a boon?

If I did this, Would I be like the kid with the only pool on the block?

I never considered cascading cylinders, I was just going to fill off the compressor. This is obviously something I don't want to flippantly jump into as my space, and time, are premium.

fire diver
06-21-2009, 09:45
While you CAN fill straight off the compressor, I would highly recommend buying several 300cf tanks to form a bank to fill off of.

navyhmc
06-21-2009, 17:04
For me, the whole argument comes down to convinience. is a home fill station a bane or a boon?

If I did this, Would I be like the kid with the only pool on the block?

I never considered cascading cylinders, I was just going to fill off the compressor. This is obviously something I don't want to flippantly jump into as my space, and time, are premium.

While you CAN fill straight off the compressor, I would highly recommend buying several 300cf tanks to form a bank to fill off of.

I agree with firediver. While the compressor at home in and of itself would be nice and even if you spent big bucks to get something with a high CFM, you will always have a hot fill, no matter what. Unless you have a very good in-line cooler, the air going into your tanks will be very hot, getting hotter as you fill the tank. This is considering that the first part of the fill might cool a little as it expanded when it got into the empty/nearempty tank.

If you had even a modest small bank of air, the bank will be at ambient temperature and you will be able to control the rate of fill so you won't get a hot fill. Granted, you can always top off later.

mitsuguy
06-21-2009, 17:47
Requirements for a compressor system:

At least some banked air in 4500 psi bottles (2 should get you 600 cf I believe), a compressor capable of 4500 psi fills, a regulator for the back side of the banked air system, Modified Grade E air quality (might require two or three filters), and a nitrox stik for continuous flow blending...

This would give you the best of all worlds... by filling the bank to 4500 psi, you can let the compressor run and give you extra capacity and the ability to fill off the back end at whatever speed you want to... Obviously a regulator so you can set a maximum pressure, with a good valve, so you can walk away while the tank is filling without worry of overfilling, or filling too fast... also, the system should be capable of filling nitrox cylinders (these would be a direct fill and bypass the bank) for continuous flow blending... a nitrox stik can be constructed relatively cheaply and easily... (granted, continuous flow doesn't require modified grade E air, but it would be nice to have the ability should you want to do a partial pressure blend)

jbres1
06-21-2009, 20:05
I have (1) 4500psi cylinder, it holds 440 cu ft of air at 4500, (2) 3600+ cylinders that hold 355 cu ft ea., and (3) 2400+ cylinders that hold 300 cu ft ea.. I partial pressure fill my cylinders, and mix what ever I need for a dive.
If you want to have a small bank, I would go with (1) 2400+(fill to 2640 psi) cylinder and (1) 4500 psi cylinder. This would give you over 700 cu ft of air to fill from. Most of the filling of your scuba tanks would be from the low pressure cylinder. And you would only need the 4500 psi cylinder for toping off. By doing this you wil be running your compressor to re-fill the low pressure cylinder more often than the high pressure cylinder. This would save wear and tear on the compressor.

Jim Breslin

Darthwader
06-24-2009, 20:26
I have (1) 4500psi cylinder, it holds 440 cu ft of air at 4500, (2) 3600+ cylinders that hold 355 cu ft ea., and (3) 2400+ cylinders that hold 300 cu ft ea.. I partial pressure fill my cylinders, and mix what ever I need for a dive.
If you want to have a small bank, I would go with (1) 2400+(fill to 2640 psi) cylinder and (1) 4500 psi cylinder. This would give you over 700 cu ft of air to fill from. Most of the filling of your scuba tanks would be from the low pressure cylinder. And you would only need the 4500 psi cylinder for toping off. By doing this you wil be running your compressor to re-fill the low pressure cylinder more often than the high pressure cylinder. This would save wear and tear on the compressor.

Jim Breslin

Thanks for that Jim. I can see now how Naive my question was to begin with. this is a hell of a lot more involved than I first thought. I never realized that filling straight from the compressor would give me a hot fill, likewise, I never figured how much more the *******sry costs would be. I'm still interested, but I've got a lot more homework in order to make sure I do this right!

TommyB
06-24-2009, 21:43
Good book to have around when doing your own fills O/2 Trimix

Vance Harlow's OXYGEN HACKER'S COMPANION From AIrspeed Press (http://www.airspeedpress.com/newoxyhacker.html)

CWSWine
06-24-2009, 21:56
Sweet Dennis!!!

Wish I lived closer. Is that the shop in topeka?

Sure is and if you up in the area stop by and check it out.

jbres1
06-24-2009, 21:58
Here is a really good link for anybody who is thinking about a home system.
You will need to sign on to the Deco stop to view the thread, but well worth it. It can be found in the compressor section of the site.
Background (http://pontificatingnobody.com/Denton-FillStation/)


go to the bottom of the page and click on the go to page areas.

Very good reading for those who are thinking. It may get you going, or it may turn you off to the idea real quick.

Jim Breslin

navyhmc
06-24-2009, 22:53
I have (1) 4500psi cylinder, it holds 440 cu ft of air at 4500, (2) 3600+ cylinders that hold 355 cu ft ea., and (3) 2400+ cylinders that hold 300 cu ft ea.. I partial pressure fill my cylinders, and mix what ever I need for a dive.
If you want to have a small bank, I would go with (1) 2400+(fill to 2640 psi) cylinder and (1) 4500 psi cylinder. This would give you over 700 cu ft of air to fill from. Most of the filling of your scuba tanks would be from the low pressure cylinder. And you would only need the 4500 psi cylinder for toping off. By doing this you wil be running your compressor to re-fill the low pressure cylinder more often than the high pressure cylinder. This would save wear and tear on the compressor.

Jim Breslin

Thanks for that Jim. I can see now how Naive my question was to begin with. this is a hell of a lot more involved than I first thought. I never realized that filling straight from the compressor would give me a hot fill, likewise, I never figured how much more the *******sry costs would be. I'm still interested, but I've got a lot more homework in order to make sure I do this right!

It's still a noble project. The best thing to do is find and make friends with your favorite LDS and pick their brains. It's a lot to learn but worth it in the end.

navyhmc
06-24-2009, 22:55
Here is a really good link for anybody who is thinking about a home system.
You will need to sign on to the Deco stop to view the thread, but well worth it. It can be found in the compressor section of the site.
Background (http://pontificatingnobody.com/Denton-FillStation/)


go to the bottom of the page and click on the go to page areas.

Very good reading for those who are thinking. It may get you going, or it may turn you off to the idea real quick.

Jim Breslin
Excellent link! Thanks for posting!!!:smiley20:

Darthwader
06-25-2009, 21:32
I have (1) 4500psi cylinder, it holds 440 cu ft of air at 4500, (2) 3600+ cylinders that hold 355 cu ft ea., and (3) 2400+ cylinders that hold 300 cu ft ea.. I partial pressure fill my cylinders, and mix what ever I need for a dive.
If you want to have a small bank, I would go with (1) 2400+(fill to 2640 psi) cylinder and (1) 4500 psi cylinder. This would give you over 700 cu ft of air to fill from. Most of the filling of your scuba tanks would be from the low pressure cylinder. And you would only need the 4500 psi cylinder for toping off. By doing this you wil be running your compressor to re-fill the low pressure cylinder more often than the high pressure cylinder. This would save wear and tear on the compressor.

Jim Breslin

Thanks for that Jim. I can see now how Naive my question was to begin with. this is a hell of a lot more involved than I first thought. I never realized that filling straight from the compressor would give me a hot fill, likewise, I never figured how much more the *******sry costs would be. I'm still interested, but I've got a lot more homework in order to make sure I do this right!

It's still a noble project. The best thing to do is find and make friends with your favorite LDS and pick their brains. It's a lot to learn but worth it in the end.
I thought about that. I'd even volunteer just for the opportunity to gain experience!

captain
06-28-2009, 11:19
I haven't bought air from an LDS since the 1970's and the only reason then was I had not yet switched to a a portable gas compressor. I have had a personal compressor since 1967. I would have quit diving long ago if I had to put up with the hassle and inconvenience of air from an LDS. If you feel diving will be a lifetime endeavor buy a compressor and never look back. I prefer a portable gas compressor, it goes where I go.

chinacat46
06-28-2009, 12:43
I haven't bought air from an LDS since the 1970's and the only reason then was I had not yet switched to a a portable gas compressor. I have had a personal compressor since 1967. I would have quit diving long ago if I had to put up with the hassle and inconvenience of air from an LDS. If you feel diving will be a lifetime endeavor buy a compressor and never look back. I prefer a portable gas compressor, it goes where I go.

Whats the TSA's take on it? Do the airlines charge you for it?

captain
06-28-2009, 13:43
I haven't bought air from an LDS since the 1970's and the only reason then was I had not yet switched to a a portable gas compressor. I have had a personal compressor since 1967. I would have quit diving long ago if I had to put up with the hassle and inconvenience of air from an LDS. If you feel diving will be a lifetime endeavor buy a compressor and never look back. I prefer a portable gas compressor, it goes where I go.

Whats the TSA's take on it? Do the airlines charge you for it?

If I fly out of the US then the tanks are rentals not my own. If it is in the US it goes with me in the Suburban with the rest of my gear.

Darthwader
06-28-2009, 21:46
I haven't bought air from an LDS since the 1970's and the only reason then was I had not yet switched to a a portable gas compressor. I have had a personal compressor since 1967. I would have quit diving long ago if I had to put up with the hassle and inconvenience of air from an LDS. If you feel diving will be a lifetime endeavor buy a compressor and never look back. I prefer a portable gas compressor, it goes where I go.

Whats the TSA's take on it? Do the airlines charge you for it?

If I fly out of the US then the tanks are rentals not my own. If it is in the US it goes with me in the Suburban with the rest of my gear.

It's definately an option I want for myself. I don't like the idea of being hamstrung by distance. I don't need a gas compressor, but I would like a well thought out electric compressor. unless things change in the next year or two, I'll probably get a small system for the garage.
I used to want a "man cave" but now it's turned into a Dive locker!

jugglematt
06-29-2009, 01:45
depending on the amount of filling you intend on doing , a small Bauer Junior or equivelent would probally be enough, i did not buy a compresor to start a shop or to fill everyones tanks , all i wanted to do was fill my tanks and who ever my dive buddy was for the day . one positive of buying a small system is you can say to the 10 new friends who turn up with tanks that you compressor is for personal filling only , and is not set up for commercial quantities

dont stress about banks , ect ect ect , just buy a new or very good 2nd hand compressor that has a local dealer who can supply parts and aftersales service . then as time goes buy and you learn you MAY want to add banks, and other stuff.

i have a had a small dive compressor for about 4 years now .the unit i purchaced was a L&w 100 which is German made and very good quality , the benifit of this system is it is rated to allow you to do Partial pressure filling of nitrox if i want to later on

of all the toys /projects and things i have purchaced my compressor it the best thing i have purchaced .

if you do a lot of diving and are concerned about the air fills your getting its worth while , i dive most weekends and live in a coastal holiday community , getting my car into the dive shop during peak season is madness and i was lucky if i could get a fill within 1 hour so the time savings are great , then add the expense of running my car to and from the dive shop . also the fact that i can fill my tanks to the pressure i require , no low fills now .

i think my compressor payed for itself in about 3 years ,

i dont use Banks , i just fill direct from the compressor.

a great investment , the cost saving is not the main benefit , the convienence is the main benefit for me ,
Regards
Matt

Darthwader
06-29-2009, 06:28
depending on the amount of filling you intend on doing , a small Bauer Junior or equivelent would probally be enough, i did not buy a compresor to start a shop or to fill everyones tanks , all i wanted to do was fill my tanks and who ever my dive buddy was for the day . one positive of buying a small system is you can say to the 10 new friends who turn up with tanks that you compressor is for personal filling only , and is not set up for commercial quantities

dont stress about banks , ect ect ect , just buy a new or very good 2nd hand compressor that has a local dealer who can supply parts and aftersales service . then as time goes buy and you learn you MAY want to add banks, and other stuff.

i have a had a small dive compressor for about 4 years now .the unit i purchaced was a L&w 100 which is German made and very good quality , the benifit of this system is it is rated to allow you to do Partial pressure filling of nitrox if i want to later on

of all the toys /projects and things i have purchaced my compressor it the best thing i have purchaced .

if you do a lot of diving and are concerned about the air fills your getting its worth while , i dive most weekends and live in a coastal holiday community , getting my car into the dive shop during peak season is madness and i was lucky if i could get a fill within 1 hour so the time savings are great , then add the expense of running my car to and from the dive shop . also the fact that i can fill my tanks to the pressure i require , no low fills now .

i think my compressor payed for itself in about 3 years ,

i dont use Banks , i just fill direct from the compressor.

a great investment , the cost saving is not the main benefit , the convienence is the main benefit for me ,
Regards
Matt
thanks Matt. one of the reasons I started thinking about a home compressor was how busy one of the dive shops was. I was in Green Bay and the place was absolutely overrun! between all the student needs and the rentals, air was cylinders were nonexistant for the weekend and fill were way behind schedule (they were busy filling student tanks).

I first decided that what I needed was several tanks so I could rotate 'em in for filling, but the more I thought about it the more I wanted a compressor. at the time though, My LDS was still open and cost was the biggest factor in not getting one. now that's changed and it about convinience and growth (Filling, mixing, Cylinder maintence, etc.) anything that will add to my knowledge base I figure is a good trhing.

CompuDude
06-30-2009, 15:40
Small compressors are cheap, but they take a loooong time to fill a tank. Do some checking before making any decisions on that score... if you have 2-3 tanks you need to fill, you'd better plan on having plenty of time to get the job done. You won't be doing multiple dive days unless you own multiple tanks.

The Great Kazoo
06-30-2009, 15:57
"If you feel diving will be a lifetime endeavor buy a compressor and never look back."

I feel the same way. I will be buying another boat soon, and this time will be looking at 54 footer sea rays. I will want to be out for a three day weekend and cant or wont come in for fills. I dont need, but want my own. To me convenience out weighs cost. I would also like to have one for my garage.
Endeavor to Persevere

fire diver
06-30-2009, 16:28
" I will be buying another boat soon, and this time will be looking at 54 footer sea rays. I will want to be out for a three day weekend and cant or wont come in for fills. I dont need, but want my own. To me convenience out weighs cost. I would also like to have one for my garage.
Endeavor to Persevere

Will you adopt me? :smiley31:

I can only afford a 25 foot 'toon, but at least it will be new.

mike_s
06-30-2009, 16:34
I was looking in to it, and thought about getting one of the "cheaper" models, you know the one, around 3k dollars. then I figured.. $3,000 / $5 per fill = 600 fills... so basically, it would take me about 4 years worth of diving to pay that off. n


that just pays off the initial purchase price of the compressor.

you'll want to add in

shipping costs for compressor, etc.
Installation costs, such as additional wiring/plugs
fill hoses/lines that aren't always included with the compressor.
electrical usage per compressor hour. Easy to figure out. just get the usuage off the compressor spec and multiple it by your kW/h rate.
filters
compressor oil
compressor rebuilt at X hours.
other required maintenance.
Soon aftewards you'll want to add a few banks and the piping required for them. And maybe a fill panel.

Pretty soon, you'll want to fill nitrox, most likely Partial Pressure filling. Vance's book is great to start with.

But then that'll require you to have everything o2 clean and even more filtration.

it's a never ending cycle that will push the limits of your wallet. but still lots of fun.

The Great Kazoo
06-30-2009, 16:35
A 25ft Pontoon IS a FUN boat. I used to have a 24 footer.

bennerman
06-30-2009, 17:03
Lol, my "L"DS is 45 minutes away, so this may become the only option for me... once I get a job, that is,

captain
06-30-2009, 22:19
Small compressors are cheap, but they take a loooong time to fill a tank. Do some checking before making any decisions on that score... if you have 2-3 tanks you need to fill, you'd better plan on having plenty of time to get the job done. You won't be doing multiple dive days unless you own multiple tanks.

What do you consider a loooong time. Mine pumps 3 to 3.5 cfm depending on weather conditions and takes 20 to 25 minutes to fill my 72's from 500 to 2600. Owing multiple tanks is even more reason to have a compressor.
I guess if you are filling 4 sets of double 120's it could be a looong time.
I have 10 72's so I can fill a few every day and be ready for a weekend of diving.

CompuDude
07-01-2009, 02:34
Small compressors are cheap, but they take a loooong time to fill a tank. Do some checking before making any decisions on that score... if you have 2-3 tanks you need to fill, you'd better plan on having plenty of time to get the job done. You won't be doing multiple dive days unless you own multiple tanks.

What do you consider a loooong time. Mine pumps 3 to 3.5 cfm depending on weather conditions and takes 20 to 25 minutes to fill my 72's from 500 to 2600. Owing multiple tanks is even more reason to have a compressor.
I guess if you are filling 4 sets of double 120's it could be a looong time.
I have 10 72's so I can fill a few every day and be ready for a weekend of diving.

20 to 25 minutes to fill an old lp 72 cf tank is not selling me on it. On an average dive day where I don't have access to fills, I'm usually diving hp130s, hp119s, or hp100s (at the smallest). If there are only two people waiting for a tank fill between dives, that's going to be one long surface interval.

If you have many tanks, I agree, most people who aren't daily divers will have all week to fill them. But if you only have 2-3 tanks, max, that fill time is going to take a toll.

jugglematt
07-01-2009, 03:53
i use a L&W 100e which delivers 100litres of air per min. when i go out for the day i come home and fill my days tanks usually 2 or 4 tanks.

first thing i do when i get home is put a tank on the compressor filling , then start washing the dive gear, camera and boat , swapping tanks over every 25mins ( i now have a countdown timer with alarm that i hang around my neck so i don't get sidetracked )

i own 4 tanks so if i want i dont have to fill every day , i could just fill at the end of the weekend , but filling each day is no big deal.

my tanks are usually finished filling not long after the dive gear is rinsed out. if your thinking you will be filling multiple tanks for a club or for all your friends shure get a bigger unit , set up banks ect ect ect . but why make things more complicated and expensive than they need to be .
simple , small compressor , plug into socket ,fill your tanks . thats it

some basic regular maintence ,
replace the prepacked air filter about every 20 hours of operation ( easy as changing the oil filter on your car)

drop the compressor oil out yearly , ( no more difficult than changing the oil on your car )

install an hour meter, and keep a log of your fills
dead easy ,

Matty

navyhmc
07-01-2009, 04:27
You are correct JM, it's not rocket science, but you do need ot know what you're doing. I like the count down timer.

skdvr
07-01-2009, 08:10
You are correct JM, it's not rocket science,

Unless you screw it up:smiley2:

Phil

navyhmc
07-01-2009, 08:29
You are correct JM, it's not rocket science,

Unless you screw it up:smiley2:

Phil

Nah, then it's sort of like auto mechanincs...with a twist.

Now booster pumps, those are rocket science!!!! invented at the Houston Space Center for Skylab.

Rcontrera
07-06-2009, 19:41
A home air system can be as easy or as complicated as you want it to be. For a basic NEW system you will need:
Compressor (gas or electric) - $3000+
Filter cartridges ($40+)
Compressor oil ($13+ per change)Then, figuring only the cost of fuel or electricity, maintenance supplies/expendable and service items, the cost of a fill is around $2-3 per standard 80. If you count in the base cost of the compressor, then we have to add in another $1 to $2 per fill.

Overall, you really don't save much over the cost of many dive shops. The big advantages are 1) you get air when you want ... no matter what time or holiday it might be. And the biggest is 2) you know the quality of the air you are putting in the tank.

The reason I pump my own air instead of taking advantage of the "free" air that has been offered me by local shops is that I am the only Me I get and I don't like breathing dirty, oily or wet air. And with times as tough as they are now, some shops are cutting back on maintenance money and filter life is being stretched a little more than they really should be.

Now ... all that said ... if you don't have the discipline to do regular oil and filter changes as well keeping the machine itself wiped down and clean, just keep making the drive to the dive shop.

Darthwader
07-13-2009, 20:03
A home air system can be as easy or as complicated as you want it to be. For a basic NEW system you will need:

Compressor (gas or electric) - $3000+
Filter cartridges ($40+)
Compressor oil ($13+ per change)Then, figuring only the cost of fuel or electricity, maintenance supplies/expendable and service items, the cost of a fill is around $2-3 per standard 80. If you count in the base cost of the compressor, then we have to add in another $1 to $2 per fill.

Overall, you really don't save much over the cost of many dive shops. The big advantages are 1) you get air when you want ... no matter what time or holiday it might be. And the biggest is 2) you know the quality of the air you are putting in the tank.

The reason I pump my own air instead of taking advantage of the "free" air that has been offered me by local shops is that I am the only Me I get and I don't like breathing dirty, oily or wet air. And with times as tough as they are now, some shops are cutting back on maintenance money and filter life is being stretched a little more than they really should be.

Now ... all that said ... if you don't have the discipline to do regular oil and filter changes as well keeping the machine itself wiped down and clean, just keep making the drive to the dive shop.

those are all very valid points, you need to have the Discipline to keep a regular maintenence schedule. that was one of my concerns, the other being knowqledge. what could wrong with a compressor that may jeapardize my air quality?
Mony never figured into it since I'd never dive enough to make a home station pay. this is all about convinience, self-sufficiency and general growth as a diver.

Rcontrera
07-13-2009, 20:29
what could wrong with a compressor that may jeapardize my air quality?
OK ... this is kind of an open ended question. I could cop out and say nothing can go wrong if you do your preventive maintenance. However, this is machinery. And there is no such thing as a "perfect" machine.

As far as what "generally" happens to lower the quality of air, the following are the most common mistakes made by compressor operators.
Failure to change filter media in a timely manner (obvious - allows oil/water to pass the filtration system)
Failure to change oil (causes mechanical damage to the compressor and can cause oil leakage past rings)
Not blowing down condensate properly (can prematurely saturate the filter chemicals)
Overheating the compressor (will "cook" oil and in some cases will create Carbon Monoxide. As a bare minimum will destroy the lubricating qualities of the oil way faster than just normal running.)I am sure that others will chime in here with their horror stories. But this just covers my limited experience (I have only been working with HP air compressors since the 70s).

fire diver
07-13-2009, 20:33
what could go wrong? Your auto-dump could fail, overloading your filters resulting in large amounts of water going into your tanks. Your oil pump could fail, sending large amounts of oil into the filters / tanks. Your compressor could overheat, causing combustion in the compressor and sending CO into your tanks. If you have a gas engine to drive the compressor, you could get exhaust into the intake. depending on the compressor location, you could get vehicle exhaust in the intake.

I'm sure there are other problems I'm missing.

Darthwader
07-13-2009, 20:49
what could go wrong? Your auto-dump could fail, overloading your filters resulting in large amounts of water going into your tanks. Your oil pump could fail, sending large amounts of oil into the filters / tanks. Your compressor could overheat, causing combustion in the compressor and sending CO into your tanks. If you have a gas engine to drive the compressor, you could get exhaust into the intake. depending on the compressor location, you could get vehicle exhaust in the intake.

I'm sure there are other problems I'm missing.
That's exactly why I posted the question. I forgot what post triggered my concern, but I was taken aback. I naively thought that all I had to do was just keep a regular filter rotatrion and everything would be fine. I realize that, As navy pointed out, this isn't rocket science, but I do need to understand the nuances of HP compressors. I just wish there were a shop close enough to allow me to volunteer. unfortunately I can't reach the former shop owner for advice.

Rcontrera
07-13-2009, 21:08
That's exactly why I posted the question. I forgot what post triggered my concern, but I was taken aback. I naively thought that all I had to do was just keep a regular filter rotatrion and everything would be fine. I realize that, As navy pointed out, this isn't rocket science, but I do need to understand the nuances of HP compressors. I just wish there were a shop close enough to allow me to volunteer. unfortunately I can't reach the former shop owner for advice.

I wouldn't worry too much about a home system. The more basic you have, the less there is to break. In all honestly, I have customers that have thousands of hours on their little compressors and have never done anything but change oil, filters and valves.

Then again, I have a couple that break everything they touch. Take a look at your shop tools right now. If you are good with your equipment and everything is cleaned, oiled and stored in a safe clean place, then you will have no problem with a compressor. If your power tools are piled up in a cardboard box in the corner, are covered with oily sawdust and cobwebs then just make the drive to the shop.:smiley2: