[chas350]

Anybody ever try an old hlvp turbine for a supplied air pump? I have a Fuji that is maybe 12-15 years old that I don't use anymore for spraying.
I was thinking if I wired in a reostat to the turbine I could turn the flow down a bit with out it over heating the air, and then run it thru 100' of hose to cool it down and purchase a supplied air hood from Hobby Air or SAS.
I wonder if the hood setup comes with any sort of filter? Or would I have to buy one separate?
Any ideas or thoughts on this guys?
Pros?
Cons?

 

[dinger]

Moving this to the garage/tools section.

 

[jaguarxk120]

I think with any supplied air system the air should be filtered. Remember your breathing the supplied air! It won't matter where the turbine is some one close by can create a dust cloud and it could be sucked into the inlet.

 

[milo]

The bigger the I.D. of the hose the easier it is to move air through it. So a 12 volt computer icu type fan can actuallly put enough positive pressure in a hose that you can draw air from if you use a check-valve type mask at the end :welcome:

Of course use some common sence and if you don't have that just hold your breath.. :evil:

 

[jaguarxk120]

Alarger I.D. hose is a very good way to go as it will lower the air pressure's required for supplying air. However you set it up you always want a flow of filtered air into the mask. You don't want to be sucking air in from the supply system.

As long as the supply air can keep the mask flushed out the any outside fumes can't get in, other wise you could suck in something you do not want to breathe into your lungs.

 

[oldred]

Two things to consider, well three actually, one is that you also want to filter the air AFTER it leaves the flow device because the air could very well be contaminated with particles of all kinds of crap from the motor/turbine, look it over good. Another thing to consider is that you need to make absolutely sure that there is no way the pressure could rise to more than a couple of PSI inside the hood or you could seriously hurt yourself. Third, if you overlook something or simply make a mistake with this thing you could very well kill yourself, you will be betting your very life that you have it right! An economy supplied air system does not cost all that much and when you subtract what you will have in a home made system it will not cost much at all, it would be quite cheap for the assurance and peace of mind it would bring when you are surrounded by those VERY toxic paint fumes.

 

[jaguarxk120]

Red glad you pointed that put about filtering the discharge of the air supply pump. If you look at SAS Safety systems you will find the pump has a intake filter to take care of the big stuff, and a very large discharge filter on the supplied air side.
The pump they use is a vane type and a large filter insures the air is very clean.

 

[hemi43]

I made one years ago, and it works perfectly !!
I used a Gast vacuum pump, which BTW is exactly what the high-end fresh air systems use. The pumps were made by the thousands, and can be picked up for next to nothing.
The vanes inside are made from ceramic, so there's no oil anywhere in the system. I plumbed the the vacuum side through some 3/4 black and mounted the intake outside, so that the air going in is fresh and cool. I also put a small filter on it to keep bugs and/or bird crap out.
There's also a filter at the pump in case anything gets by.
On the outlet side of the pump, I run a 3/8 hose parallel to my pressure hose that goes to my gun.
This hose then goes up to a modified half face mask.
If you're interested, I'll take some pictures and post them.
Dan

www.dantechfabricating.com

Here's a link to the same type of pump I used
http://cgi.ebay.com/Gast-Compressor...umps?hash=item335003b573&_trksid=p3286.c0.m14

 

[jaguarxk120]

Please do post some pictures. I have the SAS compressor, but a full face mask. Kind of hard to see with glasses on. Thanks.

 

[Jon]

Yes, pics please.

And if there's a significant difference in price between the homemade version and a comparable commercially-available version, I'd be interested in putting this in the wiki.

 

[jaguarxk120]

The SAS Safety unit for one person runs about $1000.

 

[hemi43]

It cost me less than $100 to build mine.
I'll take some pictures and post them in a few hours.
Dan

 

[hemi43]

OK ! Here's the pictures.


Pic 1- this is the air inlet in behind my shop. It's located just above and to the right of the window. it's actually a small silencer that's used for air tools, but I'm using it as a primary filter.

Pic 2- this is the vacuum pump located just outside my spray booth. the air is plumbed through black flexible water pipe. The filter was on the pump when I bought it. I only paid $50 for the pump !!

Pic 3- I added this picture to show that US Safety uses the exact same pump. They want well over $1000 for the pump !!

Pic 4 is a picture of my mask. I use a standard half face mask, but removed one of the filters. I machined an adaptor that screws in it's place so that I could attach the 3/8 surgical tubing. I wear the orange belt which has a canister with a couple of filters, but it's really not needed. At the end is a quick change standard foster fitting. I removed the one way valve so that there would be less restriction

Pic 5- this is my pressure regulator on the booth wall. The fitting to the right is the outlet for the fresh air which goes to my mask.


This setup has worked great without any problems for well over 12 years. Make sure you use 1/4 hp or higher. Smaller pump will not have enough air volume. If you have any questions, just PM me or send me a message at www.dantechfabricating.com
I

Dan

 

[jaguarxk120]

I got my pump at a flea market for $20, the guy didn't know what he had. Same pump.

 

[hemi43]

Everytime I see one cheap, I grab it !!
They are also great for vacuum bagging when making laminated parts.

 

[oldred]

I think the hobbyair start out at about $390 for the outfit with a half-mask, this is for the complete ready to use system. When you consider this is less than the cost of a quality spray gun and even less than a gallon of high end paint for a properly engineered system it is not expensive at all.

 

[hemi43]

still four times what I paid !!

 

[chas350]

Two things to consider, well three actually, one is that you also want to filter the air AFTER it leaves the flow device because the air could very well be contaminated with particles of all kinds of crap from the motor/turbine, look it over good. Another thing to consider is that you need to make absolutely sure that there is no way the pressure could rise to more than a couple of PSI inside the hood or you could seriously hurt yourself. Third, if you overlook something or simply make a mistake with this thing you could very well kill yourself, you will be betting your very life that you have it right! An economy supplied air system does not cost all that much and when you subtract what you will have in a home made system it will not cost much at all, it would be quite cheap for the assurance and peace of mind it would bring when you are surrounded by those VERY toxic paint fumes.

Good point Red, I am sure my turbine vanes are full of crap from spraying.
I would use a good filter on the discharge side though, but I wonder how the air would smell? After all, this was used to spray paint and has sucked in over spray every time I used it.

 

[oldred]

still four times what I paid !!

But for an extra $290 you have a new, clean, professionally engineered system that is ready to use and will work and work properly, for instance do you know how much positive pressure you have in your mask? Do you have any idea how much pressure is safe? Excess positive pressure can be harmful over time. You say it is the same pump and maybe it is OR maybe it is the same external case with parts made of different materials inside meant for a different purpose, I have no idea if it is the same but do you? I am not trying to say your system is dangerous but I think the questions I ask are legitimate when you consider how much is at stake here and for the price of a gallon of paint a person can have a real engineered and ready-to-use system rather than a collection of parts that look as if they probably will work, they very well might but? Again I am not trying to argue that your system is no good but the facts are that you are using a pump that was built for a different purpose and there is more assumption here than engineering that the collective parts are going to perform properly. Anyone considering trying to build their own system should consider the real possibilities of unforeseen problems rather than just glowing reports of a cheaper home built system that may or may not be working as good as the owner thinks, anyone considering doing this needs to ask "am I willing to bet $290 on my health and maybe my life that I will get it right"? Remember if any of the system is built using the wrong parts or materials any particles, chemicals or lubricants that enter will be pumped directly into the user's lungs, add to that the possibilities of overly high, or too low, positive mask pressure and $290 becomes a real bargain.

 

[hemi43]

First of all, you don't have to be a rocket scientist to design a positive pressure face mask. I am not a scientist , but I am a professional in my trade.
(tool maker for what it's worth )
You obviously don't have full compressor pressure going to the mask !! Clean air basically flows by your face at a constant rate, and you breathe in what you need. Any excess air or pressure, is expelled by the one way valve in front of the mask.
If what you're saying is true, then I guess riding down the road with the wind blowing in your face is very hazardous !!
As far as breathing particles ?? You're in a BODY SHOP environment !! You'll breathe in more particles in the thirty seconds it takes putting on your fresh air system on than the whole time wearing it.
These pumps are oil less, so the chances of breathing in oil are nil !!
You'll get more oil in your system firing up that old Chev than you would painting fifteen cars.
Sometimes common sense can save you lots of money, but if you have lots of it, go ahead and waste it on some gadget that will most likely be made and engineered in China and will be of inferior quality.
Having said that, I would not go out and design an SRS system (air bags ) for my car !!
Dan

www.dantechfabricating.com