pgtruspace's blog

about things that interest me.

Category Archives: AirWasher

The Completed, New Old Project

The completed New Airwasher, a miniature Industrial fume scrubber .

see our patent. and patent drawings

We want to put these units out on long term loan to those that donate to our R&D effort, please indicate any interest in this comment thread below…pg


7inch x 12.5inch x 12inch high – 175 x 320mm x 300mm high T6c-Airwasher

The project of the last 2 years  is completed and several of these miniature industrial Airwashers are now being used by my family members. They are testing it’s operation under real conditions of cleaning the air in their homes and to offer their critique on it.

The funnel to the left of the scrubber power  head is for an upended 2 liter soda pop bottle to supply additional makeup water as it evaporates and to maintain the proper operating water level within the machine. see below.

T6c Airwasher

With the supply bottle in operation the machine draws 58 watts of power as it cleans about 60 cubic feet of air a minute, while trapping the pollutants in the 4 liters of water in the clear acrylic plastic tank  bellow it.

With the exception of the water tank and the 2 Liter “pop” bottle, all of the plastic parts were created out of about 1 kilogram 2+ pounds of ABS plastic on a small Desktop 3D Printer from files created with a desktop computer. Truly a manufacturing empire on my kitchen table! …pg

Any interest in this device should be added to the comments below…pg

The New Old Project – multiplication

The song of the little Robot is silent for the moment as I consider my kitchen table of little fume scrubbers and contemplate, my NEXT number.

A multiplicity of scrubbers

A multiplicity of scrubbers

The Black Airwasher on the left has been working for me for a couple of weeks as We , the robot and I, create new additions to it’s family. The Blue and Whites are nearly ready to go out into the world. All spiffy in their livery and labels. They just need motors and containment tubs to be completed.  There is a also a box, a Large Box, full of scrap and failures to show for my learning experience along the way. I am pleased with both the appearance and function of these tiny industrial fume scrubbing machines.

( man I have got to get a better camera or learn how to better use this one)

As this is an R & D effort, completed Blue and Whites will be sent out on permanent loan to those that donate $250 to my effort, so that they can evaluate, under real world conditions,  and offer their wisdom for needed improvements.  And I can continue to buy coffee for me and filament & electricity for the robot.

If interested in this device,  click on: Comments  and inter your remarks…pg

Next is to design and create a better water management system and base to replace that food container. This thing is getting too big for the little printer’s build bed. I must section and then glue up this next addition that will make the Airwasher more user friendly. Adding 16 oz. of water every 4 hours is a necessary thing,  but an annoyance. A 2 liter water supply bottle or even two of them would make servicing only a daily chore. The hand made ones of 25 years ago had this feature and it was planned on in the consumer model, but this little printer was just too small for the needed build footprint…pg


February 22,2019  update

i1035 FW1.1

And there it is ! I will need to rework the files for a better and easier to print addition to the Airwasher but it works!  😎  hurrah !

If interested in this device,  click on: Comments  and inter your remarks…pg

My adventure in 3D printing

monoprice iiip

Monoprice 3D Printer IIIPv2

This Little 3D printer is about the minimum usable, as well as inexpensive, machine available.   $250 at this date.

2 years ago I purchased this little machine, with it’s 200mm x 200mm ( 7.8″ x 7.8″) build plate, so my grandson could get acquainted with this new technology along with his computer abilities. Last fall with the nearby Camp Fire and attendant bad air quality, I was reminded of the need for my  water based air cleaners. I REALLY needed to get new ones built! even if just for me and other family members. So I set the printer up next to my computer and began the design. see: A new old project & The new old project continues. My sister prevailed on me to help launch this new business, it became important to share what I have learned, so she and her son could become familiar with the technology without starting from total

The question of the cost to be a part of using 3D printing was posed and after some thought I replied; “ I am amazed at how little I have spent for the things that this little IIIPv2 printer, Optiplex780 computer and I have accomplished over the last 3 months. For less then a thousand dollars we have created things that would cost me tens of thousands and 2 years, 25 years ago. The 21st century is an Amazing place to this 20th century man…pg


An excellent pdf on filament printing for a beginner starting out…pg

Back in 1986 I took a temporary job fabricating equipment for the Silicon Valley electronics industry. Equipment such as tanks, containment trays, fume duct work and fume scrubbers created from shaped plastic sheet stock parts Hot air welded together with a hot air welder and plastic rod.  Plastic welding requires that the material be heated to the point that it will flow and stick, but not yet a fluid as one uses in metal welding. Plastic is made up of long chain hydrocarbons much like spaghetti that must be heated to the point that it is much like wet cooked pasta that will flow and stick but not break up or have it’s structure destroyed, a rather fine line of temperature that is particular to that type of plastic or alloy of plastics. 3D printing of plastic filaments is carried out under much the same conditions. In this case a miniature extruder under the control of a computer directed robot is laying down “welding rod” to create an object.

The job of the operator is to evaluate the conditions, manage the heat energy and material applied, to create the conditions for a good weld buildup of the part.

Due to the nature of the device being used the building part must remain solidly in place on the build bed during it’s creation. Much of the problems encountered in 3D printing center around keeping the building part in stuck in place. Then, at the end of the build the part should be easily removed so that the bed alignment is not disturbed, the bed surface is not damaged or warped, and the next part can be started.


Printer Notes:

New printer setup:

First thing, check all fasteners for tightness, Modestly tight, not finger tight, not OMG tight, but well fastened. All attachments must remain stable. The software assumes a stable machine and the printer does not self correct for any displacement during operation.

Set printer on a resilient bed such as ridged foam, hard rubber foam, etc. This will greatly reduce noise transfer and reduce resonant movements as the build bed and the mass of the printed object is rapidly moved under the Extruder head. Tie down the “Z” towers solid to frame, with angle braces or attachments to enclosure frame. The towers MUST be stable to the frame, there must be no chance of induced wobble during print bed movements. Any wobble can result in the nozzle encountering the solid work piece, causing a displacement that will ruin the work and may damage the printer.

We will be using ABS so heat management is critical for best results. The operating printer bed must be in a very warm, draft free environment, so an enclosure of some kind is important for consistent results. Being able to see the results of the printer’s operations as they happen is valuable, so the operator can observe, make any adjustments needed is very useful, so a “window” should be considered.

Periodic service before printing:

To insure that the part remains “stuck” to the print bed during it’s creation is critical to success. Be sure to clean bed covering of all dust and oils. Isopropal Alcohol works best, Acetone will work but will damage PEI coverings. Or add a glass covering, glass will require additional time to heat up ( 15-20min.), any glass will work and is less likely to be damaged by use, thicker glass will be less likely to warp, but glass will need additional fasteners to prevent movement on the bed table. Glass adds to the mass of the bed that will be in motion as well as it requires changes in the bottom limit switch position due to it’s additional thickness. We are using a Borosilicate glass covering as that has the best”stick” while hot and best release when cooled. Do not touch the bed covering after cleaning. To improve “stick” of the part to the build bed, various materials are often used to act as temporary “glue”. We are using ABS dissolved in Acetone as our sticking agent for most parts and sometimes Painters tape for really difficult to stick, critical large parts. The Painters Tape is the last resort as it is difficult to remove after the completion of the print. Also used by others are Hair Spray, paper glue stick, as well as salt and sugar. All water based that will stick hot and pop lose on cooling. many people print small and light pieces with no glue and others use special build plate coverings that seem to work with no additional adhesion.  When printing with ABS it is critical that the piece remain warm and well adhered to the build bed during the build process. Any draft that might cool the bed, part or Extruder can ruin the work as well as the “stick”to the bed. Temperature MANAGEMENT is critical while working with ABS!

It is critical to adjust the machinery to be properly aligned, the Extruder must move parallel to the bed to lay even layers onto the surface of the build. In our type of printer the part creation bed moves back and forth in the “Y” plain under the Extruder. The Extruder moves in the side to side motion of the “X” plain and is supported by it’s carriage that is moved in the “Z” direction up to lay down the layers. In our case the Extruder carriage  is controlled by two stepper motors that sometimes get out of synchronization, measure the distance of the carriage rods over the bed to be sure they are parallel to the bed. If not, they can easily be rotated into alignment while the printer is off. While energized they are electrically locked together.

To “level” or trammel the bed to printer nozzle there are adjusting thumb wheels or nuts in each corner of the bed. These are adjusted corner to corner, at least 3 times around. As you adjust one corner the diagonally opposite one will change as the bed teeters on the other two corners. Typewriter paper works well as a thickness gauge. Nozzle should just barely “grip” the paper to the bed. This must be completed on a “Hot” bed to be true for heated operation. It is very important that the first layer be properly stuck to the bed. We use “brim” as an attachment enhancement, as it adds no additional height to the parts, something that is critical to maintain measurements when several parts are assembled together. Once the printer begins the “Brim” the first deposition from the Extruder can be examined for good attachment to the build plate as well as the proper “squish”width and thickness.
It is at this time that I do final adjustment of the bed.

There are also now add-ons that will test the bed surface distances and read into the Gcode the needed nozzle position to properly stick that first layer.

After the print is completed and the print bed cools I slide a sharp thin blade under it to help release it from the bed. The more gently you can remove the part the better to prevent warpage or displacement of the bed adjustments.

Sharp thin blade tool:

I took a good quality, flexible putty knife and ground one side into a wood chisel like sharp edge. To assist lifting the part or for scraping the build plate I use it bevel side up to get under the brim and part to begin lifting them. Caution! Do not use this on a warm soft build plate cover material such as PEI, it will cut right through them, use only on glass or other hard materials.

Software We are using:

Acad 17 is being used to model the parts and export them as stl ‘s. There is also 360 Fusion available to private users as well as several free 3D modeling programs. These stl’s are actually cross-sections of the parts that are being exported into the Slicer that reads these files and then computes the needed instructions that the printer carries out. Printers are dumb, they are a very simple computer that only handle specific movements and temperature. Slicers convert the object into step-by-step directions for the printer to follow. Things like, maintain temperature, start extruding, move x-axis 10 mm and y-axis 2mm, and so on. Most of those commands start with a G, hence the name Gcode. A slicer translates the model slices into the needed movements, speeds and temperatures that are set in configuration instructions which the printer understands.

“Repetier-Host”, A freeware program, is being used to import the stl files and manage the “slicer” that creates the Gcode files and serves those instructions to the printer. Cura, A freeware program, is a slicer that is used to create the needed Gcode files that instruct the printer on how to execute the creation of the required piece. These Gcode files are the instructions that operate the “printer” to build the object one layer at a time by depositing material in amounts and position as dictated by the results of information developed by the “Slicer” program . The needed Gcode is specific to the printer being used and the slicer instructions are set in configuration before the slicer is engaged. The Gcode files are served to the printer through WiFi, or a USB connection or via. a SD card by Repetier-Host the server program that the “slicer” it is embedded in.


Early problem was prints were so porous that water would readily go through the walls but the tops and bottoms were quite solid. Found that tops & bottoms set were default set at 3x and the walls at 1x. I reset the tops & bottoms to 2x as well as set the walls to 2x. This increased the time required and material used but resulted in a substantial improvement in part quality.

increased the extrusion rate 10% to get a stronger more solid part and the result was…

As I was attempting to print the third of 3 motor bases, again I hear this pop and the printer dislocates the “X” axis at about the 1.1 inch line, What the heck! This was 3 times in a row at about the same point, damaging the print. now I will have to section off the top quarter of an inch of the model and print 3 of those and repair all 3 motor bases. But why ?  I sleep on this problem and…  of course! the extrusion is too high. We have been making the layers just a bit too thick and after an inch of layers the build was too high and during a travel move from side to side the no longer high enough nozzle impacted the build so hard that the “X” belt jumped the sprocket and the machine lost it’s registry of position, always at about the same spot.  Reduced the extrusion rate, end of that problem.

notes from 3D Printing:

Pg Sharrow One of the things I learned during years of plastic welding is that every formulation of plastic and COLOR behaves differently. White is different from Black. Blue or Red. Every time you change supplier or color you must change your technique.
Rob Smith I would print a temp tower… Believe it or not, every spool has its own ideal temperature, even if it’s the same material in the same color from the same manufacturer. Cura has a plugin called “ChangeAtZ” that makes it easy to change the temperature at specific layers, and there are dozens of models on Thingiverse to choose from. A good temp tower will have features that highlight bridging quality, overhangs, stringing control, and of course, surface finish. I like this one:

Rob Smith No problem! Protip: the temp tower is a great diagnostic tool, but it’s not the only one. There are a bunch of prints that are popular for “benchmarking” your printer’s performance… Lately Benchy has been the most popular ( and before that it was Marvin (… but if you’re really looking to fine-tune your printer, there’s a collection of carefully-chosen calibration prints to challenge your sanity:
If you have the chutzpah to try printing all of them a) remember each one is a unique purpose-built test, and it’s designed to be challenging, and b) post pictures!


#3DBenchy – The jolly 3D printing torture-test by by CreativeTools
 for setup of the IIIPv2 in Curia

Aaron Greengrass Printers are different enough from each other that there are no ‘standard’ settings. My hotend has had 4 different layer cooling fans. Each one requires a number of changes to print settings to get a good print. Of the 9 printers I’ve owned so far, only 2 have even been vaguely similar, and even they didn’t have identical settings. Test, adjust, and test again. Print slower. Watch a lot of youtube videos about dialing in printer settings. Look at the print troubleshooting pages (the one simplify3d has is pretty good). Expect this to require trial and error. Expect also that whatever settings you get working will require changes not only for different types of filament, but in many cases for different colors (ie translucent vs solid color print very differently)

Todd Saltzman The way you have to approach it is when your print comes out bad you need to identify what exactly is bad about it. Such as is it over extruding or being too stringy etc. then you need to look at the solutions to your problem and just adjust small things at a time.
advise and links I greatly appreciate…pg
link to hot end assembly and PID tuning :

The New old project continues.

T6b Airwasher

T6B Airwasher

There it is, Airwasher T6B that now sits on my kitchen floor quietly humming away cleaning about 60 cubic feet a minute of air while using 60watts of power. Made of Grey ABS plastic. on a little Monoprice IIIP printer (see below). It sits in a 1 gallon food container and took about 40 hrs of print time and most of a spool of filament. Quite a learning experience in Acad and 3D printing.

Monoprice 3D Printer IIIPv2

Now that it is reality, I can contemplate and easily create improvements. I must say, having a manufacturing facility in my tiny Computer Lab is amazing to me. Quite literally, the magic of the 21st Century that I read about in the mid 20th SiFi pulps, is now real.

This morning I sat here marveling at the magic of modern technology that makes this possible. A tiny Hurricane that I have trapped in a container, is cleaning the air in my room while I sit here communicating that fact with the rest of world.  Tesla’s rotating electrical energy system, mass produced computers systems and the World Wide Web of communication makes all of this possible, even for a poor man living in a cabin out in the middle of the woods.

the first post on this project A New Old Project.

January 21 201 the latest Airwasher T6 c; blue & white

This one in black, is operating on my kitchen floor next to my computer 😎 lab. I think This model incorporates all of the improvements that it needs…………..for now.

The bucket is a semi-clear 1 gallon food container. Nice to be able to see the interior operations and water levels.

Airwasher T6 blowup

T6 Genii Whirlwind Airwasher

lots of parts. Uses the motor from a high quality swamp cooler circulation pump.

Any interest in the codes to build one for yourself should be voiced in comments below….pg

A New Old Project

The Genii Whirlwind Airwasher

While blogging in the dark of smoke and power outage of the Camp Fire. I struck up conversation through an Internet Link with my youngest sister about my need for one of my fume scrubbers. The last of the hand made ones died last year. My grandson and I had purchased a small 3D printer last year to begin creating a new model. Something some of us need from time to time to breath and sleep during periods of poor air quality. My sister , a recently retired educator was interested in helping her brother in creating a business to manufacture and market this consumer market Airwasher that I had developed over 25 years ago and had failed to successfully bring to market.

old airwashers

People that used the hand made units really loved them, including myself but the unknown changes in motor quality by the motor manufacture right after I started creating them doomed that effort and often caused premature failure of the devices. An economic down turn at a critical time caused my prospective investors to backout and the effort collapsed.  The Proposed consumer model was abandoned. Oh well, I moved on.

With the Internet and 3D printers we might be able get this going for something less then the $500,000 that I was looking at the last time and if my sister and her adult son take an interest they might be able to create a real business for themselves and I can continue my other projects. Finance and business management are among her talents and her son is an independent craftsman/tradesman type. This might even work out and I won’t have to do everything myself like the last time.     Ok ! lets go for it!

Once again I am digging into Acad and creating files to be printed for test models that can evolve into Beta units that will result in injection molded retail consumer units.

Quality, Swamp cooler water pumps are providing the motors for the new effort and the possibility of designing around the right kind of motors for the job. I need to set up a printer cabinet in my cozy computer Lab.  😉 Lol while doing test work in the kitchen. Getting the water pickup, air flow and effective scrub action while making efficient use of the motor without overloading it will be the next challenge.  Every part must be laid out so it can be created by the printer, no small thing. This requires 3 dimensional visualization and planning. Luckily with Acad, the computer can Show me the proposed part  before I print my mistakes.  Next learn about how to operate a 3D printer to print this 4 part power head that is the motor enclosure, water pickup and scrub blower.

1 airwasher

Wow! that is close to actual size on my monitor, 5 inch blower ring and 6 inch motor mount disk. While I’m resting I will need to figure out the scrubbing scroll and air guides …pg


December 9  I just got the Acad file done on the above, looks good enough to print. All of the internal parts are laid out. Now to set up the printer and figure out how it works. Take these Drawings apart and rasterize the individual parts for the printer to render into plastic. The AirWasher box is 7 inches square, as large as the little 3D printer can make, I would prefer 10 inches for better scrub action. I may attempt a glueup for later testing or we may set up a larger printer later.

Then I can test to see if 25 year old memories are still valid. Only took 2 weeks to get fairly comfortable in Acad again. It certainly renders nice visuals, Almost as good as a real picture….pg

January 2 2019 update……you can see the improvement in my CAD abilities as well as the design improvements in the proposed Airwasher as well as my grasp of 3D printer use.

Airwasher T6 blowup

T6 Genii Whirlwind Airwasher

The white container is an off the shelf, semi-clear poly, 1 gallon food container. The motor is from a quality swamp cooler water pump. The rest of the scrubber parts are all printed on a small 200mm x 200mm deck printer. The real device is not quite as colorful as we only have one color of filament, but HR remarked about how color coding being a real help in CAD work. While peering into a complex 3D CAD file can be very confusing, the contrasting colors are a big help, as is the ability to move from wireform drawings to realistic renderings as needed, this is a wonderful improvement in doing CAD work.

As you can see the power head and scrub sections lift out of the bucket for ease in daily cleaning. No screens, no filters, no added chemicals, just water and 60 watts of power to really clean the air in a large, 300 square foot room. Dust, pollen, chemical vapors, nearly anything that can harm you can be removed with this Industrial fume scrubber. Wow! I have impressed myself this time.

monoprice iiip

Monoprice 3D Printer IIIPv2

About the smallest, most inexpensive, usable printer on the market, $250 on Amazon

This little robot is quite an impressive toy as well.  My small closet sized computer lab is now a manufacturing Empire!   😉  …pg

January 8 2019  I now have a test unit running for 2 days. So nice to have an Airwasher running in my space again. Dust levels inside already are decreasing and smell is freshened. Needs improvements, but at least it works. My Lady, my sister, my daughter, all want a copy of their own. Still having problems mastering the printer to get dependable results. Seems to require some spell or secret knowledge. Maybe a bigger better printer would solve my problems?  Maybe, someday,……