Air-assist Compressor advice

[Riki Potter]

Hi guys, I've red through alot of older threads on this subject and they pointed me in the right direction.
The biggest factor for us is noise level, we have a flat upstairs that we don't want to torture to much.

Will this one be adequate for a laser?
http://www.gordonharris.co.nz/mini-compressor-asi8ki-pc-BRAC-100.html

They also stock a diaphragm compressor although the guy I spoke to recommended the piston type linked above. Here's the diaphragm one http://www.gordonharris.co.nz/well-made-mini-compressor-pc-HIW2814.html

Is there some type of blower that works for air-assist? By blower I mean something that doesn't compress air into a tank but just blows through the pipe when needed.

Thanks in advance :)

[Dan Hintz]

If you find the correct diaphragm type (as in, correct output pressure/flow), that's the easiest to go with... inexpensive, small, not very noisy, etc. Search on posts by Dee and compressor, I think she found something that fits the bill to a T for less than the one you listed above, designed for nail salons, so very quiet.

[Mark Sipes]

My laser came with a Medco Linear Air compressor. very quite with good airflow 1 moving part.

What voltage? 220 50 Hrzt Check AU Ebay ....... Aquaculture, Fish Tank, Fish Pond Aerator Pump

Industrial air pumps.......check local pond supply shops.

[Joe Pelonio]

As Dan said, I use a an airbrush pump from Airbrush City and it was only $39. has lasted 4 years so far with heavy use, and
quieter than my exhaust fan. I suppose the same model is double that now but still inexpensive. I also saw a similar one for $89 at harbor Freight.

[Gary Hair]

That Harbor Freight compressor is ok for occasional use but if you run it too long it will burn up. I had an acrylic job that I ran for almost 8 hours a day for 3 days - about halfway through the first day it was toast. I ended up getting an oil bath compressor from HF, it's louder than the airbrush compressor but way quieter than most others.

Gary

[Glen Monaghan]

I have a HF airbrush compressor and it got too hot to touch when left running for long jobs. I started putting a small fan next to it, blowing across the compressor's fins and around the main body, and that has kept it "just warm" during extended operation.

-Glen

[Riki Potter]

After searching a bit more and finding a few more guys who stock them here I've found the standard price to be ~$300 ($250USD). My boss is happy with paying that amount, we really want to get one from a store so we can check it out and everything first. I'm guessing it'll be very difficult to find the cheaper ones you guys are talking about over here, retailers don't get much demand for a large range of them so they stock the more expensive models only to make it worth it for them, it happens alot over here unfortunately.

Thanks for the input guys, I'll look into the options you brought up then go from there.

[John Noell]

Another option is the Gast diaphragm pump. On a rubber mat it is extremely quiet and can be run for long times. Epilog sells them.

[Mark Sipes]

I guess I will take my linear air pump and ball and go home.....

[Joe Pelonio]

I have a HF airbrush compressor and it got too hot to touch when left running for long jobs. I started putting a small fan next to it, blowing across the compressor's fins and around the main body, and that has kept it "just warm" during extended operation.

-Glen
OK, I guess the HF is one to stay away from. The one I got from Airbrush City has run as much as 20 hours without overheating. Before that I had a more expensive Badger, a little louder but didn't overheat, but after two years I wore out the bearings.

[Mark Sipes]

I have an Iwata Sprint that I bought from Dixie Art and have had it for 10 years. I run the compressor for 8-10 hours a day. It is used to power the spindles on the Newing-Hall Engravers. I mounted a computer box fan on the top for additional cooling and run the air through an old freon tank, that way when the system builds up to 50-60 psi. the compressor turns off until the system hit 40 psi. Cuts the compressor run time to 1/4.

[Eric Ucci]

Ricki,
I know its been a while since you posted. But, I wanted to check back in with my experience...
After reading this and other posts, I followed Dee's advice and purchased a TC-60 from http://www.tcpglobal.com. With a high end of 57 PSI it looked promising, however, at .6 CFM (@57 psi) it turned out not to be up to the task. We were looking to achieve a constant 30 psi in our air assist. With no CFM rating to go by it was a little trial and error.
So, after that didn't work, I looked further, using low DB rating as my next most important criteria. I ended up looking into the California Air Tools line of compressors. You can go on youtube and see many videos of sound comparisons. I was shocked at how quiet they are. See the video of the compressor I bought here: http://www.youtube.com/watch?v=t1gDSDsGod4
Here are the specs of what I bought....

California Air Tools Compressor
Model 6310
1 HP
120 V
6.3 GAL
3.8 CFM @ 40 PSI
2.35 CFM @ 90 PSI
60 DB

See full specs here
http://californiaairtools.com/ultra-quiet-oil-free-air-compressors/cat-6310/

229263

Purchased from Home Depot online for $225 (pricey, but worth it as far as I'm concerned)

After setting it up, I have to say it is quieter than in the video, the cfm output is more than enough and I couldn't be happier. Now we'll just have to see how long it lasts :)
Also, Its not as big as it looks from the photo (23"Lx21"Hx10"W)

Anyhoo....
Thats my 2 cents.

Shenhui SH-1490 150w reci
Shenhui SH-690 60w

[Dee Gallo]

Eric,

I am wondering why you need such high air pressure. Does the laser you have require that much? Or do you just feel like you want more pressure? Epilog specifies only 10 psi needed, which is hardly anything, which is why the airbrush compressors work so well.

curious, dee

[john banks]

Kerls font cut through 1/4" hardwood at say 1/2" height. With high air velocity it comes out with no further work to be done. Without lots of air this sort of cutting just chars beyond redemption, too delicate to sand aggressively or to use masking tape.

[Michael Hunter]

The little Gast compressor which came with my Epilog allows me to cut 6mm hardwood cleanly, giving a "polished" light brown edge.

I'm wondering whether the efficiency of the air jet is as (or possibly more) important than the pressure and the airflow?

[john banks]

When I narrow the nozzle to 2mm instead of 4mm the small compressor behaves like the big compressor in terms of results with short focal length lenses, but unless I modify the cone I cannot do this with longer focal length lenses which work better with thicker wood because the laser so far above its focal point when it exits the cone has too wide a beam. Hence our upgrade to a 3kW compressor which has been hassle in terms of power supply, cable and pipe routing between buildings, fittings, air preparation from a bigger oily compressor, control etc.

How wide is your nozzle and what pressure and flow do you get from your Gast? Our Epilog demo showed much more charring than I was happy with, but I don't know what spec of compressor was used, and feel that the demo was not representative of the machine but more the setup and knowledge of the rep.

[Eric Ucci]

Eric,

I am wondering why you need such high air pressure. Does the laser you have require that much? Or do you just feel like you want more pressure? Epilog specifies only 10 psi needed, which is hardly anything, which is why the airbrush compressors work so well.

curious, dee

Dee,
I'd say pretty much what John Banks already said regarding higher flow rates w longer focal length lenses on wood. We've been cutting 10mm BB ply. Results are dramatically improved when you use 30 psi vs 10 psi. I'm not familiar with the epilogue air assist. With the Shenhui, the opening in the end of the nozzle is 4.5mm dia. and I couldn't get the airbrush compressor to maintain 10 psi. It didn't have sufficient CFM.
With a 63.5mm lens, the higher rate of air helps quite a bit. I'll be testing out some longer focal lengths once I get them but I'm assuming the higher air flow will be invaluable with a 100mm lens. I've been able to cut 3/4" solid hardwoods (w 63.5mm lens) with edges that are too charred to be passable. I'll give it another shot when i get the 100mm lens. I don't expect that cutting 3/4" would make sense for production runs, but we like to tinker...

Shenhui SH-1490 150w reci
Shenhui SH-690 60w

[Tim Walters]

Hi All,

I use a CPAP machine (the kind used for sleep apnea) for my air assist.

It's VERY quiet, made for long hours of operation, has good airflow, and it's made to push into a fairly long hose.

You can also adjust the flow rate.

You might find one on Craigslist.

Tim

[Adrian Hernandez]

The goog thing about using the airbrush compressor is if you found the compressor to be too noisy you can build a silencer box and installed inside just like the parablaster company does.


Eric,

I am wondering why you need such high air pressure. Does the laser you have require that much? Or do you just feel like you want more pressure? Epilog specifies only 10 psi needed, which is hardly anything, which is why the airbrush compressors work so well.

curious, dee

[Dee Gallo]

Our Epilog demo showed much more charring than I was happy with, but I don't know what spec of compressor was used, and feel that the demo was not representative of the machine but more the setup and knowledge of the rep.

I spoke to an Epilog tech about the charring issue and he said it is more about the power you have than the air assist. The lower powers require more burn time which equals more char, plain and simple. Since I have a low powered laser, the amount of char I have is only controlled by the frequency and maximizing the settings for max power at max speed which will do the job. The quality and type of the substrate makes a big difference.

[john banks]

We've been running the 3HP compressor (typo when I said 3kW above) for a few weeks and it is has given a massive improvement in our hardwood cutting (we use 2 bar or 29 PSI and see great improvements between 0.5 bar and 1.5 bar, and a little more to 2 bar, with no further benefit in our application beyond that). We turn down to 0.5 bar for everything except hardwood cutting. We're awaiting a cone extension so we can get the cone nearer to the work when using longer focal length lenses which should be useful.

[Riki Potter]

Thanks for all the replies lately guys. I'll have a look at the CPAP machines, I'm pretty sure my step-dad uses one so he may have an old one somewhere if I'm lucky.

I went to the big petshop here and got their biggest air pump, unfortunately it was still only made for large fish tanks and didn't have nearly the amount of flow we need. I contacted our laser supplier at the other end of the country and he had a search around and sent us the specs for a silent compressor minus the tank, for $1500!!! No thanks at that price.

I'm still to find a working solution but I also haven't had alot of time lately to look for one but hopefully soon. At this point my first choice would be a big fish pond pump then maybe the CPAP then an airbrush compressor.

[Phil Horne]

Just a though, but I have heard that some people have had good results using nitrogen to control flaming. you can get a T-bottle of nitrogen from your local welding supply place and the regulators aren't to expensive. That might be something to look at for jobs that charring is an issue on.

Phil

[Riki Potter]

Thanks Phil, it sounds intriguing. I would assume it would work better than air due to the nitrogen starving the flame?

I'm still undecided on whether we would actually benefit much from air-assist, would it allow me to cut thicker materials? Or does it just nicen up the end result?