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Motor (Gasoline, Diesel or Electric)
- Pressure Pump
- Pressure Hose
- Trigger Gun
- Unloader Valve
- Pressure Wand or Lance
- Wand or Lance Tip
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THE PRESSURE WASHER MOTOR
Different sorts of motors are used for different types of pressure washers. It may also depend on the type and location of the applications. Most high power washers used in industrial works, commonly use gasoline or diesel motors. Because most industrial cleaning requires great amount of time, these motors could run much longer without overheating compared to their electric counterpart. And since most industrial works are done outdoors; and sometimes or mostly offsite, where there are no available electricity. The ones with electric motors are mostly used for light to moderate washing works (e.g. house, car, and small boats) and are the most excellent used for indoor applications because these motors do not emit harmful fumes.
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HIGH PRESSURE PUMP
You've now arrived at the "core" of the system, the high pressure pump. All are positive displacement reciprocating pumps either piston or plunger types. Plunger pumps are the most efficient and have a longer life, therefore they are the most commonly employed pumps found on a quality power washer today.
There are duplex and triplex plunger pumps. Plungers are typically made of ceramic, a very hard material with excellent wear resistant characteristics. The triplex pump has become the most popular due to the smoother flow it creates.
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These pumps are incredibly robust and virtually trouble free when properly maintained. Most people suspect the pump first when experiencing a problem but amazingly 90% of problems can be traced to causes other than the pump.
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HIGH PRESSURE HOSE
A high pressure hose is composed of an inner tube in which the water flows. This is wrapped in either a single or a double braid of wire mesh. This is in turn surrounded by a rubber outer cover. The cheaper hoses are covered in a thermoplastic material the better hoses have rubber covers. Most hoses are manufactured with burst ratings 4X their rated working pressure. When matching hoses to machines try to use a hose rated slightly higher than the psi rating of your machine. It will last longer. Typical psi ratings are 3000psi, 4000 psi, 4500 psi, 5000psi and 6,000 psi. 3,000 and 4,000 psi hoses are generally single braid while 5,000 psi and above are virtually always double braided (2-wire).
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A good pressure washer hose is the same design principle as a hydraulic hose. The basic construction is as follows:
- Inner Core - This is the inner core in which the water actually flows.
- Wire Wrap - This is the wire wrapper that surrounds the inner core and protects it from damage. This wrap is in a braided configuration which allows the hose to bend freely while having ample protection. Most Hoses under 4500 psi ratings have single wire wraps and are referred to as "single wire or R-1" hoses. Hoses designed for psi ratings of 5,000 or above and hoses designed for hot water use have two wire braids and are referred to as "2-wire or R-2" hoses.
- Outer Cover - The best covers are rubber, thermoplastic covered hoses are widely used on pressure washers that are designed to be sold at a cheap price. If quality is important to you I would be skeptical of machines that are sold with a thermoplastic hose as standard.
Exception: The most notable exception is in the case of sewer jetting. In this case the pressure washer is designed to unblock and clean sewer lines. For this application 1/4" and 1/8" thermoplastic hoses are an advantage due to their ability to make extreme bends within pipes.
The standard size for pressure washer hoses is 3/8"OD (outside diameter). This is because the vast majority of pressure washers are rated between 3-5 gallons per minute flow rates. If your system exceeds a flow rate of 5gpm or if you are planning on using more than 100' of hose continuously then consider 1/2"OD hose. Many lesser pressure washers of dubious quality market pressure washers with 1/4" thermoplastic covered hoses in 25' lengths. For me this has always been a tipoff to investigate quality issues further prior to any purchase. Standard quality hoses come in 50 ft lengths.
TIP: If you are planning to use 100 ft or more hose continuously don't buy a 100 ft hose, buy two or more 50 ft hoses and link them together the reason being that if a hose goes bad or wears out you can keep working and you don't lose an extremely expensive hose. A black or red rubber hose can leave marks on surfaces, this can be a concern when pressure washing roof tiles or when doing flat work on concrete. In these cases use blue or gray covers these do not leave marks or scuffs and are referred to as "non-marking hose". Yellow coverings are typically made so that the hose is more resistant to the effects of oil, grease, and animal fats these are often used in rendering plants and other industrial applications. If you are working at heights, remember that all the weight of the pressure washer hoses when filled with water can be pulling on the hose fitting. The best manufacturers sell pressure washer hoses that are skived before coupling. Skiving means the outside rubber cover is partially removed to allow the metal fitting to be crimped to the wire braiding of the hose. This process provides a solid metal to metal solution with good strength.
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TRIGGER GUNS
Considering there are numerous styles of pressure washers, the appropriate trigger gun should complement the whole pressure washer to maximize it for best use and there are also different styles available to pressure washers today.
• Pistol Style Guns
• Straight-Through Guns
• Front Entry Guns
• Rear Entry Guns
• Dump/ Weep guns
• Open Guns
Trigger guns that stop the water flow are the most commonly used guns in power washer systems equipped with unloader valves. Front entry guns are common on the lesser priced units and rear entry guns are far and away the most popular. Rear entry guns do a better job of keeping the hose out of the operators' way and are better balanced. These guns control the water flow via a spring, ball and seat which are actuated by the trigger. When the trigger is released the ball is pressed against the seat by the spring and water, aided by a check valve in the outlet of the unloader. Water is "trapped" in the hose under pressure and the pump enters bypass mode. With this setup you will experience some "kickback" when you squeeze the trigger so be careful when using ladders and other types of access equipment. Dump Guns and open guns are operated without unloader valves because they don’t stop water flow.
The standard pressure washer trigger gun which almost every manufacturer supplies, either a front or rear style pistol gun which stops the flow of water and necessitates the need for an unloader valve. These guns have long been considered to be the industry the standard.
HOW PRESSURE WASHER TRIGGER GUNS WORK
Generally the gun will have a 3/8" inlet port where the hose is attached and a 1/4" outlet port to the wand/lance.(this is when 3/8" pressure hose is used.) When the trigger is released the gun is said to be in “closed” position stopping the flow of water. When the trigger is squeezed it is in “open” position directing water to the nozzle once again.
These trigger guns control water flow by means of a spring, ball and seat. The trigger controls the on/off of the water flow. When the trigger is released the ball inside the gun is forced to seal in the seat by the spring and the water flow. This effectively stops the flow of water and sends the unloader valve into bypass mode. When the trigger is again squeezed the flow of water and spring force the ball from the seat and water is once again directed to the high pressure nozzle.
Pressure washer trigger guns are designed for safety. The design of a trigger gun allows it to go to closed position if the operator loses control or drops it. This is the safety mechanism of the trigger gun. Pressure washers, especially that of industrial type can discharge fluid at a whopping 31,000 psi, and if you happen to drop and lose control of a trigger gun, this may have damaging consequences.
There was once a report that a Pressure Washer rental was sued by a renter who claimed he lost control of the gun and was “cut open” from mid-thigh to his chest causing him to be unable to work for an extended period of time. As a result we had 25+ trigger guns impounded as evidence. Investigators later learned that this “roof cleaner” regularly used tennis balls to keep the trigger gun open to avoid the “hand fatigue” that can be caused by squeezing a trigger for an extended period of time. Although today’s pressure washer trigger guns are well designed for safety, don’t negate these safety features by using tennis balls, duct tape or some other method to artificially hold the trigger. Instead look into purchasing an “easy pull” pistol style trigger gun. These are designed to require a much lesser force to pull the trigger than a standard style gun.
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THE UNLOADER VALVE
This is the main "safety" in your power washer system. The most commonly used is the "pressure actuated" type valve. When the pressure gun trigger is released the valve senses the pressure build up and like a "traffic cop" it diverts the water flow from the pump outlet back into the inlet side of the pump this is called "bypass mode." Without this critical component this closed-gun situation would build pressure to the point where it would stall the power source, rupture the gun, hose or even the pump itself.
The most basic function of the unloader is to act as a "traffic cop" to the water flow in your system. Depending on the type of valve it will either sense "pressure build" or "reduction in flow". Depending on the type, when one of these conditions is met the unloader will then actuate to divert the water flow back to the inlet side of the pressure pump, where it will circulate through the pump back to the inlet side of the valve to the inlet side of the pump again in what is called a bypass loop when this is occurring the pump is said to be in "bypass mode" and the unloader valve is said to be "cycling". This scenario ends when the trigger is squeezed alerting the unloader valve to redirect the flow to the high pressure nozzle once again. While this may seem to be problem solved it is not without risks. When the water flow is in bypass new cool water is not entering the system. The moving parts in the pump are creating friction which produces heat that is transferred to the water flow in bypass. Since a limited amount of water is in bypass this transfer of heat can occur quickly.
Most pumps are designed to handle water temperatures of 140 F. When the water in bypass reaches 155? F damage to the pump will begin. Damage can occur to the pump packings, plungers and seals and even to the short bypass hose in external bypass setups. It is a good idea to have a pump with a thermal relief valve to offer some protection against excessive heat buildup. It is a better idea not to leave a pump in bypass mode for more than 2-3 minutes, by simply squeezing the trigger gun you will introduce new cool water into the system.
There are three types of pressure washer unloader valves.
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- The "Trapped Pressure" These are commonly referred to as just "Pressure" type. This type of valve opens to bypass when it senses the pressure build up of the pump output having nowhere to go. The main characteristic of this the most commonly used valve is how it traps the pressure in the hose when the trigger of the pressure gun is released. The disadvantage of this type of valve is the spike of pressure felt by the operator and pressure washer components when the trigger is again squeezed. This creates a "kickback" effect on the gun/wand so be careful when using ladders or other types of access equipment.
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The "Flow Type" unloader valves activate the bypass loop when it senses the lessening of flow between the valve and trigger gun. The major characteristic of this valve is that no pressure is trapped in the hose thereby eliminating the pressure spike created by the "trapped pressure" valves. The main disadvantage of the flow type unloader is that you can't change the pressure by downsizing the orifice size of your nozzles. The valve senses the loss in flow and begins to cycle repeatedly.
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- The “Compensating Type” Unloader Valve is a most recent addition to the world of unloaders is the compensating type unloader. This concept is a hybrid between the flow and trapped pressure unloader types. Basically this is a trapped pressure unloader with a compensating feature which radically lessens the pressure spike typically felt with the standard trapped pressure unloader. The concept of this unloader is to have the smoothness typical of a flow type unloader without the inherent disadvantages.
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HIGH PRESSURE NOZZLES
These simple seemingly insignificant components are what make the whole high pressure system work. Pressure washer nozzles contain a small orifice which is sized to create the desired pressure at a specific flow. This orifice is a restriction in the water flow. When the flow from the pump is forced through this restriction pressure is created. It is only now that you have a pressure washing system. Pressure washer nozzles with an orifice that is most closely sized to the specs of your pump will give you the optimum performance. The high pressure nozzle is a much more important component to the power washer than most realize. This creates the restriction that allows the water flow to become "pressurized" and delivered with such force. A worn nozzle will reduce pressure noticeably. A mismatched orifice can have the same effect. A nozzle with little to no wear and one with an orifice properly sized to your pumps' output will get the most performance from your machine.
 
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These pressure washer nozzles are color coded to indicate what pattern (degree) of fan spray they produce. Although colors may vary depending on the manufacturers, described below are what is commonly used as the industry standard.
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The red tip is the zero degree nozzles - these pressure washer nozzles produce a pencil point pattern, there is no fan created so this is not the tip to use when cleaning coverage is desired. The red tip does deliver the highest impact as it concentrates the pressure into the smallest area. Avoid damaging wood or other fragile surfaces. This is an ideal tool for cleaning under the deck of a lawnmower, removing caked on mud from equipment, cleaning stains from concrete, masonry, steel and aluminum even removing the grass from cracks in the sidewalk.
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The yellow tip creates a 15 degree fan pattern. These pressure washer nozzles are referred to as chiseling tips. Held at a 45 degree angle you can use it like a scraper to remove peeling paint or mildew. It is also used for other tasks where breaking the bond is harder than average. Of your different pressure washer nozzles, you will find yourself using this one the most often when the task is tough. This is the only situation I know where you'll find that when the going gets tough the tough gets yellow.
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The green tip produces a 25 degree fan pattern. This is a wash tip. These pressure washer nozzles are the ones to use when breaking the bond between the grime and substrate is reasonably easy. These can also be used for sweeping leaves or debris from flat surfaces or curbing. These pressure washer nozzles have the widest variety of applications as the fan degree allows for good impact pressure and cleaning coverage.
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The white tip is the 40 degree fan tip. The wider dispersion of the impact pressure limits these pressure washer nozzles to rinsing and delicate washing. These are the tips to use for washing/rinsing glass or washing vehicles. These are great tips for wooden decks and all delicate substrates.
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This is the last post is from a series of six on
Everything You Ever Wanted To Know About Pressure Washing.
Part One : What Is A Pressure Washer
Part Two : How Does The High Pressure Washing Work
Part Three : What Can A Pressure Washer Used For?
Part Four : How To Use A Pressure Washer
Part Five : What Are The Different Types Of Pressure Washer
Part Six : Parts Of A Pressure Washer
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The easiest way to learn how to use a power washer is to first understand how the power washing systems work. There are four basic elements of the power-washing process regardless of what machine or method you use. The four elements and power washer tips are: pressure, water flow rate, cleaning solution and heat. If we take out just one of these four elements, the cleaning characteristics will change. For example, if you can only afford a cold water pressure washer instead of hot water washer, you will have to compensate for that loss. In other words, pressure washer basics tell you that you will have to add more chemicals, apply higher pressure and use more water to achieve better power wash results. Therefore, you will always have to make adjustments combining these four elements in order to achieve the ideal cleaning atmosphere for your particular job. Nevertheless, when learning how power washing systems work and how to power wash, keep in mind that detergents emulsify the dirt better and faster as the temperature increases. This is especially true when cleaning oil and grease from a concrete surface. That's why hot water power washing systems are perfect for such jobs.
This is the fourth post is from a series of six on
Everything You Ever Wanted To Know About Pressure Washing.
Part One : What Is A Pressure Washer
Part Two : How Does The High Pressure Washing Work
Part Three : What Can A Pressure Washer Used For?
Part Four : How To Use A Pressure Washer
Part Five : What Are The Different Types Of Pressure Washer
Part Six : Parts Of A Pressure Washer
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USES OF PRESSURE WASHER
- A pressure washer cleaning oil-logged asphalt
- Graffiti removal
- Car Wash
- House Washing
- Industrial Washing
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In its extreme high pressure form, water is used in many industrial cleaning applications requiring the removal of surface layers as well as dust-free cutting of some metals and concrete. For exterior applications, gas or propane powered pressure washers provide enhanced mobility not available in electric models, as they do not require use in proximity to an electrical outlet. However, for indoor applications, electric pressure washers produce no exhaust and are much quieter than their gas or propane powered counterparts.High-pressure water at medium pressure, in combination with special chemicals, aids in the removal of graffiti. This process (especially when the water is hot) is used as a quick rinser of the softened graffiti. Sometimes people use a pressurized mixture of air/sand or water/sand to blast off the surface of the vandalized area, thus etching the surface and therefore making it extremely difficult for anyone to ever use high-pressure cleaning as a follow-up process. Sandblasting, when used in graffiti removals, often over cleans a surface and is capable of leaving a permanent scar on the building surface.
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SOME USES OF PRESSURE WASHERS ACCORDING TO CATEGORY OF APPLICATION :
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RESIDENTIAL:
Car Washing
Driveway Cleaning
House, Garage, Porch
Boat, Jet ski
Motorcycle, ATV
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COMMERCIAL:
Graffiti & Pool Cleaning
Constructions (e.g. Bricks, Tiles)
Ship Deck & Engine Room Pressure Cleaning
Farm & Construction Equipment
Buses, Trailer Homes
Airlines, Trains
Schools, Restaurants, Parks & Recreational Areas
Roof, Gutters, Sidewalks & Sewer Drain Jetting
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INDUSTRIAL :
Silos, Smoke Stacks & Vessels
Storage Tanks, Fuel Depot
Live Stocks, Poultry Farm, Livestock Pen & Stables
Gas Station, Refineries, Tanker Trucks
Off-Shore Platforms, Oil Rigs & Refineries
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This is the third post is from a series of six on
Part One : What Is A Pressure Washer
Part Two : How Does The High Pressure Washing Work
Part Three : What Can A Pressure Washer Used For?
Part Four : How To Use A Pressure Washer
Part Five : What Are The Different Types Of Pressure Washer
Part Six : Parts Of A Pressure Washer
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It is in fact the process of breaking the bond between the dirt and the surface being cleaned. As we mentioned earlier, for the best results you will combine four essential elements. However, shortfalls do exist. Here is another example of how pressure washers work: let's say you notice you have a little detergent left and you decide to decrease the amount injected through pressure washer. A cleaning solution decrease in this case will have a less effect on the debris being cleaned. Because of that, now you must work with other elements to make up for that loss. You have to increase the pressure, water temperature and the water volume. Even though, you are less likely to reach the same level of efficiency (by decreasing the amount of detergent), you will somewhat neutralize that loss.
This is the second post is from a series of six on
Everything You Ever Wanted To Know About Pressure Washing.
Part One : What Is A Pressure Washer
Part Two : How Does The High Pressure Washing Work
Part Three : What Can A Pressure Washer Used For?
Part Four : How To Use A Pressure Washer
Part Five : What Are The Different Types Of Pressure Washer
Part Six : Parts Of A Pressure Washer
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| A pressure washer is a mechanical sprayer that uses high-pressure water to clean and remove mold, grime, dust, mud, and dirt from surfaces and objects such as buildings, vehicles, and concrete road surfaces. Equipment can be rented or bought that produces pressures from 50 bars (750psi) up to 1200 bars (30,000psi) or more. |
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The most basic pressure washer consists of:
- A motor which directly drives a water pump
- High-pressure hose
- Trigger gun-style switch
- Nozzle Tips (Depends on the intended applications)
Just as a garden hose nozzle is used to increase the out flowing dynamic pressure of the liquid, a pressure washer adds its own power to force high-dynamic pressure. Note that the pump does not draw more water from the pipe to which the washer is connected than that source can provide; therefore, the water supply must be adequate for a given machine to be connected to it: its flow must be equal or superior to that of the washer, so that the pump is never starved (which can damage it).
Several different types of nozzles are available, each useful for a particular application. Some nozzles cause the water jet to be ejected in a triangular plane, while others emit a pencil-thin jet of water, which spirals around rapidly. Most nozzles attach directly to the trigger gun.
Some pressure washers, in combination with a particular nozzle, allow detergent to be introduced into the water stream, assisting in the cleaning process. Two types of chemical injectors are available: a low-pressure injector and a high-pressure injector.
Pressure washers are dangerous tools and should be operated with due regard to safety instructions. The water pressure near the nozzle is powerful enough to strip flesh from bone. Objects in the water supply can be ejected from the nozzle at great velocities. The cleaning process can propel objects from the surface being cleaned, also at great velocities. Pressure washers have a tendency to break up asphalt if aimed directly at it, due to high pressure water entering cracks and voids in the surface.
Most readily available consumer units (commonly found online or at hardware stores) are electric or gas-powered. The electric ones plug into a normal outlet and use/produce cold water, and typically deliver pressure up to about 2000psi. Gas-powered units can often deliver twice that pressure, though due to the hazardous nature of the gasoline exhaust they are unsuitable for enclosed and/or indoor areas. Some models can generate hot water, which can be ideal for loosening and removing oil and grease.
This is the first post is from a series of six on
Everything You Ever Wanted To Know About Pressure Washing.
Part One : What Is A Pressure Washer
Part Two : How Does The High Pressure Washing Work
Part Three : What Can A Pressure Washer Used For?
Part Four : How To Use A Pressure Washer
Part Five : What Are The Different Types Of Pressure Washer
Part Six : Parts Of A Pressure Washer
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With a compact design and inovative design, this Ryobi is ideal for cleaning around the home and garden. This model has a large 1600w motor and a flow rate of 360l per hour. Onboard storage. Usually comes with a 2 year warranty as standard.
* 120 bar Pressure
* Powerful 1600 watt motor
* Compact design for easy transportation
* Lance with adjustable spray nozzles
* Sturdy housing for added stability
* Spray gun and detergent tank included
Technical Specification of the Ryobi RPW-120E Pressure Washer
* Power input: 1600 watt
* Water flow rate: 360L/hr
* Pressure: 120bar
* Hose length: 6m
* Weight: 8Kg
The Ryobi RPW1400E Pressure Washer is the new model from Ryobi. It has a 1400W motor and operates at a maximum pressure of 100 bar with a maximum flow rate of 360 litres per hour.
Although lightweight at only 8kg, this domestic washer (which comes with a 2 Year Warranty) is ideal for smaller cleaning applications. Due to the unique design it is a sturdy tool. The variable jet lance is fed by the 5m hose. It is usually supplied complete with detergent gun for the tougher jobs you may face.
Pressure Washing Companies work with pretty extreme pressure, temperatures, and some pretty nasty chemicals to do their jobs.
Take into consideration that some deck strippers are rated at 13 on the Ph scale. Some of the acids used are rated at 1 or 2 on the Ph scale.
Think about the amount of damage that 4,000 PSI can cause in inexperienced hands to wood, siding and concrete. Shouldn’t there be some type of protection for consumers against these extremes?
Consumers are protected when legitimate companies share information with each other, work together and help each other. Car trunk pressure washers don’t even have a BUSINESS license now and they don’t care. Misdemeanor? So what? What do they care? They eventually have a breakdown and can’t afford to fix the equipment and go out of business. It’s just like gun laws, make a law against it and the only ones breaking the law are the ones who don’t care about the law anyway.
Does this have more to do with drawing a fence around established companies to make it extremely difficult for someone young like DJ with a lot of ambition, but no money to get into the business? I’m not saying that is your motive Henry, I’m just saying that is the first most obvious motive for anyone suggesting licensing.
When it all boils down there are only a couple of reasons to even consider licensing PW companies. Which of these do you agree with?
1) To raise more money through the state the same way licensing does now. That is why licensing fees are considered a TAX.
2) To make it difficult for entry into the business to protect existing interests.
When will we learn?
How many guys who’ve built up good profitable businesses will be knocked out because of past legal problems? How many good, honest businessmen will be regulated out of business? How much more will we have to pay for supplies when your talk about harsh chemicals results in the interference of the government making them almost impossible to get?
What about freon? Anybody used to be able to buy freon. Someone with no evidence claimed it harmed the ozone layer. It was almost 20 years before the claim was proven to be 100% FALSE, but an entire section of government had already been created to deal with a non-existent threat and because of that I can’t even juice up my own air conditioner anymore. AND LOOK AT WHAT HAPPENED TO THE PRICE!!!
You’re asking for the wind. If you get it you will reap the whirlwind.
The chemicals you are speaking of can be purchased by anyone. Licensing pressure washers will do nothing but add another tax that you have to pay each year. This is an open end tax that will do nothing but go up.
Any Joe homeowner can buy a 4000 psi pressure washer. How is licensing PW’ers going to protect them? Because if you have to raise your prices to cover legal expenses and training required by licensing more and more of those poor consumers are going to resort to doing it themselves.
What’s keeping you from getting a contractors license now and pointing out to your customers how more “legit” you are because you are licensed?
I vote no. This is one industry where some one with a little money, a lot of integrity and a lot of ambition can start with nothing and go a long way.
Is licensing currently in the talks or on the agenda? An official stance on this from the UAMCC would be appreciated.
My house is 40 years old. The exterior trim – between the brick facing and the eaves – is painted wood, a dentil-molding. The trim has probably been painted 4 or 5 times, last time ten years ago. This trim is filthy and I’d like to clean it before winter. Can I use a pressure washer to clean it? Or is there a better way? Thanks.
A ryobi pressure washer will do fine. An experienced user will know what chemicals to use for cleaning as well as the pressure and jet sizes to use. To DIY just be careful and try to stay even with your cleaning.
Yesterday I went to Sears and they had a floor model pressure washer (ie, used) 2550psi Craftsman for $203. Came with everything and appears new, but when I got it home and tried to start it, it failed About 40 pulls later my arm was too sore to continue and I gave up.
With pressure washers, more than any other product I can think of, you can’t go cheap. You need to spend more than $200 (new) to get something decent. I went through two that were under $200 in the SAME DAY. One broke after about five minutes, and the second broke just after I finished my job (thankfully).
I haven’t purchased one since, but if I ever have a need, I’ll put up the money for a good one.
Should I use my ryobi pressure washer to wash a previously stained cedar fence?
As there are many different PSI washers available, there are different tips you can use. Just don’t use a 0 tip and don’t get too close to the fence with the wand.
The hotter it is, the faster you have to work. Try to work in the shade when staining and keep a wet edge. If the material dries and you overlap you will get what we call a “flash mark” – meaning that the material will be shiny in the overlapped area.
