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Hi Steamchick and Balta, I've been selling air compressors for the best part of 45 years and have found that the small dental compressors sold by Bambi are the most reliable and quiet on the market. Unfortunately they have stopped making the oil lubricated units so the best option is to look on ebay or gumtree for something like a Bambi 75/80 or the 75/150 oil lubricated units. The only difference is the size of the receiver. The 80 has an 8 ltr receiver and the 150 has a 15 ltr receiver. both units give 54 ltr per min at 6 bar. These compressors run at a noise level of 55 dBa ay 1 mtr so to the human ear are virtually silent. The reason that they are no longer available from Bambi is that they can no longer get piston rings for the pumps, also most dental surgeries require oil free units which is fine for my company as it increases the service and maintenance costs. Hope that this helps, regards Graham T.
 
Thanks Graham, I recall the annual service of some Broome-Wade compressors (Huge beasts!) that were oil-free and required the carbon rings (3-piece stepped joints) for the 12" bores to be replaced after a year of running. But these huge compressors had to be oil free to operate the pneumatics in a paper mill - without contaminating the paper with oil mist from exhausted air. I assume the few lbs. of carbon dust got lost in the millions of tons of paper...
My dentist did some cleaning work on me a while back. I asked her if the compressor was in need of a service, as I could taste the machine oil from the air-drill.... But she said "sorry" - as she had just serviced the drill and over lubricated it...! I was bit surprised that it used machine oil - but very light -however she assured me that although oil should not be ingested, there was only a "tiny drop" so I should not be expected to die from it! - She was surprised I could identify the possible source - the compressor - or even identify the taste of machine oil!
Ho Hum...
K2
 
The air drill should be an air spindle, designed and originally produced by ABL of Ferndown, Dorset. This company has been taken over by a Chinese company. There is also another company called ABDev. And former was a client of mine and the latter is still a client of mine. Dental surgeries cannot have any oil in the air for the drill or blow gun as it will contaminate the drilled tooth and stop the filling bonding with the tooth. So if you can smell or taste oil when the dental surgeon is working on your tooth be aware that you are liable to have a problem with the filling.
I service around 50 dental compressors as well as around 200 screw, hydrovane and industrial air compressors. These compressors range in size from fractional horsepower up to over 100 HP where we open the side door and walk inside. We do have some fun at times, Try changing a set of electric motor bearings on a 100 HP electric motor. Please be aware that oil lubricated compressors are being phased out for dental work and replaced with oil free units. The filtration for oil lubed units is very critical and any taste or smell needs attention, urgently.
 
GrahamJTaylor49 - do you have any thoughts on the current batch of "quiet" compressors coming out of China? In the US a typical unit marketed by a company called California Air and they seem to have specs similar to the Bambi 75/80 you mentioned.
 
I havn't come across these Chinese "Quiet" air compressors yet but the reason that Bambi stopped producing them was because the couldn't get anyone to make the piston rings. They used to buy the compressor pumps in from a manufacturer in Sweden, strip them down and machine the pistons and fit a compression ring on the piston. Unfortunately, unless the ring manufacturer was going to supply the rings by the thousand they weren't interested in making them. Also, as the market for dental and medical compressors was turning towards oil free units it just wasn't an economic proposition to carry on marketing the high quality Bambi units. They still supply what they refer to as their Budget range of low noise oil lubricated compressors for such applications as roof vents and air brush work. I don't know what the quality of the Chinese compressors is like but I suspect that they leave a lot to be desired. I have found that their bench vices are made from cast iron rather than nodular steel and if too much load is put on the jaws they tend to snap the front off rather than bend the handle. You get what you pay for in this world and cheap is not necessarily the best value. I have found in the past large amounts of casting sand inside the webs of Chinese lathes and mills. Not the best for longevity of slideways and quills.
 
GrahamJTaylor49 - do you have any thoughts on the current batch of "quiet" compressors coming out of China? In the US a typical unit marketed by a company called California Air and they seem to have specs similar to the Bambi 75/80 you mentioned.
I've had one from Lowes in the shop for over a year. A small one, enough to blow things off, pump up tires, and run an airbrush. It will run an impact gun or air chisel for only a few seconds at real full power. These are very quiet, you can forget to turn one off and if the shop stereo is on you may not hear it cycle.

They would be of marginal use in a shop using larger air tools to any extent, but are lovely for my needs most of the time and save you the jarring noise of an oil less compressor kicking on right while you're doing something fiddly. These days, if kitting a shop out I'd probably go for a battery powered impact gun and a quiet compressor rather than a large loud compressor.

I don't know anyone with a "large" quiet compressor, all the ones I've seen are out done on air delivery by my noisy 30+ year old Craftsman oil less. Infernal racket, but it's only used for framing nailers and large tools these days.
 
...
I don't know what the quality of the Chinese compressors is like but I suspect that they leave a lot to be desired. I have found that their bench vices are made from cast iron rather than nodular steel and if too much load is put on the jaws they tend to snap the front off rather than bend the handle. You get what you pay for in this world and cheap is not necessarily the best value. I have found in the past large amounts of casting sand inside the webs of Chinese lathes and mills. Not the best for longevity of slideways and quills.

Thanks for your thoughts. They are about what you'd expect for the price ($200-300), I think. I use one intermittently with a Tormach mill for a power drawbar and Fog Buster setup, and the drawbar needs enough pressure that the compressor runs at near maximum (120 psig). I find that it is pretty loud at that pressure, around 65 dB. In the 5 years I've owned one, parts have been replaced several times including one pressure switch and one pump unit. I keep thinking about replacing the CA unit in my basement with an Eastwood scroll compressor but that probably isn't significantly quieter and is also low end. At $2k it is also a lot more money.
 
Ok I’m in need of some boiler info. I’ve looked at some YouTube videos and they scarf me to death. I can’t believe some of the work published.
So I’ve studied se boiler tech already we need heat , need a tank end caps for horizontal boiler if it’s electric, need something for the unit to rest on he heater if using a stove top . Need air in with small blower. Now what are the stack of tubes for. I’m guessing additional surface area to heat the water . Then I assume the water Lee must be above the upper most layer ov these tubes , need a path for steam to the steam done where we tap into for supply line to engine engine exhaust can go into stack to help with circulation . Need various fitting bungs , whistle and safety valve. Stem on off valve for engine port for filling below height of water in boiler . Have to see where minimum level is and where max level is . Water pump needs to be able to it water in while steam is up . Temp gage , maybe low side and high side, pressure gage . What does the siphone line do?
Is there a start up proceedure for electric boilers Watlington makes Emmer’s ion heaters but I have not contacted them .
If I’m missing something feel free to educate me .

as I noted I can’t have a fuel boiler in the house so I’m stuck with electric PM has a kit but their sit doesn’t explain what what is in it.
byron
All boilers use heat. The design is based on where the heat is coming from. A startup procedure is based upon that design to drive air from the boiler and gradually heat the metals so it does not tear itself apart until its at operating temperature. You also want to have the water circulate so you do not uncover the heat transfer surface and send the local metal temperatures to failure. Because electric elements can be placed inside the vessel the design process changes for the heat transfer. However you still need to consider internal circulation and pressure vessel design. If you look at the new appliance Instant Pot which is basically a pressure cooker the heating element is located inside. What it does not have is a feedpump to maintain water level nor level controls, or a blowdown system to control build up from solids in the water. But it applies heat electrically and it is equipped with a vent valve. The extra design consideration is how to seal the electrical wires to the heating elements. Not a trivial design issue. Not an impossible one either. One issue I saw in some of the first electrical boilers was the generation of hydrogen because the heating elements were electrodes. I doubt electrodes are used anymore. But of course you can use a pressure cooker concept with a stove supplying the heat. It will be more difficult to control the heat input.

In general you will need:

A steam flow or pressure gage to control how much heat is being applied
You need a pressure relief valve capable of the full capacity of the heating element.
You need a water column to monitor the water level with a low water cutoff.
You need a design to give a reasonable steam velocity out of the boiler with if possible good quality steam.(no water all saturated or superheated)
You should have a pressure gage to monitor what is happening
The feedwater system usually uses a valve and a check valve working in conjunction with the water column .
Some of the old steam engines did use a thermal compressor simple but a little tricky to design.

Lots of ways to skin this cat as the saying goes. The main questions would be how big, and how do you really want it to work.
 
I'm looking at a compressor at Harbor F. Naturally I have my doubts as to whether or not I could find a comparable one from Lowes or Home D that would fit my needs. I am getting one of the small "stand up " type because I have limited space. I needs it for a plasma cutter, and the usual other things.

Does anyone have any suggestions over HF? Theirs is 300$.
 
Richard Hed,

Do you have a link to share on the HF compressor you're looking at?

What pressure and CFM output are you looking for?

What kind of current draw and voltage can you allot to your compressor?

I think I know that humidity is a concern in your area: Is this a concern for you?

--

I have a large air compressor, but I got a small "hotdog" compressor from HF for inflating tires and blowing away dust when I didn't want to start up the big one. It runs erratically and the brush-type motor burned up a set of brushes after a low number of hours run time. I made a set of brushes from generic ones and keep it going so far. It works for what I use it for, but I would not want to depend on it. "Your Mileage may vary" with the model you are looking at.

--ShopShoe
 
Richard Hed,

Do you have a link to share on the HF compressor you're looking at?

What pressure and CFM output are you looking for?

What kind of current draw and voltage can you allot to your compressor?

I think I know that humidity is a concern in your area: Is this a concern for you?

--

I have a large air compressor, but I got a small "hotdog" compressor from HF for inflating tires and blowing away dust when I didn't want to start up the big one. It runs erratically and the brush-type motor burned up a set of brushes after a low number of hours run time. I made a set of brushes from generic ones and keep it going so far. It works for what I use it for, but I would not want to depend on it. "Your Mileage may vary" with the model you are looking at.

--ShopShoe
https://harborfreight.com/air-tools...i-oil-free-vertical-air-compressor-64858.html
I want at least 125 lbs pressure, and CFM, not sure, but the plasma cutter I have uses 70 Lbs pressure and the use I put it to is always interrupted, (otherwords, not 100% of time). I don't believe there is an issue on that.

I went down to HF yesterday to look at that particular compressor, a small standup type (issues of space in my shop) and the motor/compressor was very small and cheezy looking. For 300$, I thimpfks I would rather buy from someone else. My wife bought me a small walmart fal-apart about 15 years ago. It lasted bout 18 months then fell apart (surprized?) but it was the thot, and I was very happy for it while it lasted. I really didn't use it that much--the amount I used it, it should have lasted 8-10 years.

I can hook up 240V if necessary, my lathe runs off that and when I get the mill hookt up, it will be that also, but I'd rather have a 120 compressor just for being able to use it someplace else once in every couple years.

I live in a "desert" area, east of the Cascade Mountains in the Soviet of Washington, it is not ALL THAT dry for a desert. When I had a compressor that workt properly, I did indeed have water issues, needed a dryer and even then had some water issues. If it rained, forget using the plasma cutter.

We have those issues: walmart fal-apart, harbor freight not worth the weight.
 
Richard,

Thank You for sending the link. I have also had the experience of finding something from HF that I might use, then seeing it in the store and deciding maybe not what I really wanted. However, sometimes HF does provide a product that fits a need at the price and one goes with it anyway.

I have been through many compressors over the years and what I end up buying is a middle-range unit that should fit a hobbiest user. The thing that kills them for me is eventual detioration of the tank, in spite of draining, maintenance, and all the stuff that should be done. Mr Pete has a few videos about his experience with compressors, including one where he puts a small camera inside the tank and decides to condemn that compressor.

The other thing that I can mention is that whatever the design, they are usually top-heavy and an attempt to move one other than a little bit can easily get scary: The unit you show would seem to be easily tip-able.

There is a possible solution to your space issue in the use of additional tanks plumbed into a distribution system you might build. The other side of that is that suitable industrial tanks are pricy. You also need to size piping to allow for airflow at a fast enough rate to keep the auxiliary tank full. In a past life, I had a 2-HP compressor in a remote boiler room feeding a 30-gal tank in the ceiling above the work area. That part of the system was at the pressure that the compressor could produce and the output of the aux. tank had a regulator and filter right before the user's connection.

I think the capacity of the unit you show maybe just barely meets your actual needs. I am not sure that 1.5HP can keep going at 4CFM: perhaps that is a best-case peak rating. With the tank shown and bursts of use it might work OK.

Back to Shopping: Is there an industrial or servicing dealer for compressors in your area? I have a source near me that sells industrial units, but can also sell me parts for brands bought elsewhere: The counter guy can be very helpful on a slow day and sometimes smaller units are on sale if I can pick one up with my truck at his store: they don't do delivery or support to homeowners but will sell if you know what you want.

The last time I bought a compressor for my garage/shop, I looked at Ingersoll-Rand at Northern, Quincy online, Dewalt at Home Depot, and Craftsman all over (Now that Sears is gone, you can buy that brand everywhere.) That was pre-pandemic, at least 4 years back. I ended up with a Sanborn 3.xx HP, 60-gal 220V unit on sale with a hefty rebate at a Menard's store. I chose that unit because I am now old enough that I think it may be the last large compressor I buy and I don't restore cars any more so I don't think I'll be pushing it hard. As I said previously, I have the HF hotdog compressor when I need to blow dust or inflate tires and that one is portable.

My wife and I are contemplating an eventual downsize, and if I continue hobby shop operations, I may be looking at one of the "quiet" compressors.

--ShopShoe
 
I'm looking at a compressor at Harbor F. Naturally I have my doubts as to whether or not I could find a comparable one from Lowes or Home D that would fit my needs. I am getting one of the small "stand up " type because I have limited space. I needs it for a plasma cutter, and the usual other things.

Does anyone have any suggestions over HF? Theirs is 300$.
I bought an 80 gallon Ingersol Rand about 10 years ago. Runs on 240v ac. I put it on a two hour timer because I forget to turn it off sometime. I paid $500 for it from my old boss. It was used as backup to the large screw compressors. Only used about two times.
 

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Thanx guys,
After all the looking, advice, and heart burn, I'm thimpfking that the HF is the only thing I can afford. My projection is it will last at least 18 months. So the next best price for a better machine is 500$ which probably would last at least 5 years. (I really don't use them much.) And so, year for year, the price is quite equivalent. In a year and a half, if I need, and who knows, I might have more moolah by then, I can get another piece of crap.

Mr. Shoe, I've never had a tank go bad on me. Where I live, it is relativley dry. Moist where u live?
 
Mr. Shoe, I've never had a tank go bad on me. Where I live, it is relativley dry. Moist where u live?

If your compressor is in a business environment a state inspector will show up one day and do some ultra sound tests and then condemn your tank. They always find a thin spot. My boat shop had its tank condemned 7 times in twenty years.

The first time I was working down in a bilge when the air stopped. Crawled out to find some greasy old fart messing with my compressor. Asked him what he thought he was doing and he claimed to be a state inspector. I asked for ID and he showed me a dirty old business card (he only had the one). I looked out the window to see he had arrived in an old rusty clunker. So I bent his arm behind his back, escorted him to the door and threw him out. The next day he was back with a search warrant and a cop.

Mark T
 
Richard,

In the Midwest, it is not unusually moist, but summertime humidity can get high. I work more in the summer, so it is not surprising that the tanks took more of a beating than if I used them all year. What got me is that this is despite draining the tanks when not in use, although in later years I got lax in that practice. Perhaps an automatic tank drain would have helped, but there is a budget involved. I had the compressors attached to an air plumbing system around my shop and installed following most of the conventions to minimize moisture and did not suffer from "wet" air at the hose-end. I can say that most of my paint jobs turned out well without moisure problems.

It seems that you have a plan to match a product to your budget and a plan to deal with failure of your purchase, so...Good Plan and Good Luck. (I think you may get more than 18 months, too.)

--ShopShoe
 
Richard,

In the Midwest, it is not unusually moist, but summertime humidity can get high. I work more in the summer, so it is not surprising that the tanks took more of a beating than if I used them all year. What got me is that this is despite draining the tanks when not in use, although in later years I got lax in that practice. Perhaps an automatic tank drain would have helped, but there is a budget involved. I had the compressors attached to an air plumbing system around my shop and installed following most of the conventions to minimize moisture and did not suffer from "wet" air at the hose-end. I can say that most of my paint jobs turned out well without moisure problems.

It seems that you have a plan to match a product to your budget and a plan to deal with failure of your purchase, so...Good Plan and Good Luck. (I think you may get more than 18 months, too.)

--ShopShoe
There are automatic drains that have timers that are adjustable for interval and duration, I got mine off AliExpress and it works great with a 1 second drain every 45 minutes and it's wired into the main switch so that when you turn on the compressor there is an immediate drain and then every 45 minutes after.
 
There are automatic drains that have timers that are adjustable for interval and duration, I got mine off AliExpress and it works great with a 1 second drain every 45 minutes and it's wired into the main switch so that when you turn on the compressor there is an immediate drain and then every 45 minutes after.

Have you got a link for the auto drain it sounds good
 
In "South Central" Pennsylvania in can get pretty damp (not like the Gulf Coast, but my air conditioning puts out plenty of condensate five months of the year). I seldom use my compressors, but when I do they run a considerable time in minimally conditioned spaces (including the garage or outside). Only one of the compressors has a full-time filter/separator, and neither has an intercooler or dryer. I always open the drain valve and blow out condensate before I trundle them back to their storage location. Both compressors are 20+ years old and I haven't had any problems.

Amazon lists a number of options for "air compressor auto drain," ranging from $30 – $145 in the U.S. Amazon UK has the electrical ones for £20 – £35, and a float version for £8.29 (Float Drain Valve air compressor automatic drain valve condensate drainer Automatic Drain Float Drain no noise Automatic drainage Air compressor drainage : Amazon.co.uk: DIY & Tools). You can get this one in the U.S. (including the 1/2BSP connections) for $29.
 

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