It appears to me that two problems have been raised. Problem 1 is rust while problem 2, which Ann raised is residue left in the nozzle. When dealing with problem two, just spray air through it until the air is discharged clean. You should do this even with the cheap nozzle on spray cans. The instructions will always tell you to invert can and spray a few seconds until clear.
Now problem Number 1 is more complicated and it was never clear to me if the problem was the tube or the nozzle. I think the author described tapping the nozzle on a hard surface and something that looked like rust came out. This was repeated in the store with other units. If that is the case there was nothing wrong with the tube, but with the nozzle assembly itself. That sounds like a simple manufacturing problem and a lax quality/inspection procedure. While that does not help the end user, it should be the case that once the nozzle is properly cleaned, the problem will be eliminated.
It is often the case that items in production are cleaned with compressed air, which can be filthy if not properly filtered. Some of the orfices got clogged early on and it was only during use that sufficient particulates got moved into place to cause the clog. The author does not mention the tank, but that could also be the source of contmination. Think dirty gas and fuel filter.
JimT wrote: " "Critic" stated the same thing, (below, on 11/20 10:06AM). You both obviously have extensive plating experience, and I can appreciate your expertise."
Sorry about the redundant post--a consequence of using the Threaded view. I don't have extensive experience, but cI spent a lot of time with close friends who run a plating shop in eastern NC. The owner researched the process and devised and built his own equipment to do electroless nickel plating. Loosely speaking, you make a supersaturated nickel solution and when you insert the objects to be plated, it plates out uniformly on every surface. Their shop was doing zinc plating and other processes, but the nickel was so popular and so robust and their quality was so high that they could charge a premium for it. Ultimately they shut down all the other lines and just did nickel. Now they are looking at retirement and their customers won't let them do it.
Chrome plating is tricky. Chrome doesn't want to stick to anything except copper, so chrome plating, e.g., an automobile bumper, involves at least one intermediate layer. It's delicate and brittle. The least scratch or flexing of the substrate violates the integrity of the plating and causes substrate corrosion and delamination of the plating.
Nickel is not as attractive--it's a shiny bright gray instead of shiny silver--but far more robust. Since it's hard and lacks the soft copper underlayer it can withstand scratches and flexing. It's often used for bearing surfaces as well as marine (salt-water exposed) components.
I'm not an expert, but it sure seems to me that electroless nickel would have been better for this application.
Larry- "Critic" stated the same thing, (below, on 11/20 10:06AM). You both obviously have extensive plating experience, and I can appreciate your expertise. So what's the answer-? There are situations in harsh environments where internal volumes such as this one described will need a robust anti-corrosion plate. How do you recommend that be handled-?
JimT wrote: "That was also my impression – the tube was chrome plated – EXTERNALLY ! What's the point of skipping the working side of the plating-?"
You cannot electroplate the inside of an object--a tube or a bore or any concavity. The electric field isn't right.
You can do a great job of electroless plating--a completely uniform coating over 100% of the object. I don't know if chrome is suitable for this process, but nickel certainly is, and it's a more robust (and cheaper) process. Seems to me that a bad choice was made.
William, that's what I thought: that your sprayer has a metal spray head, which would allow that storing process. I did notice the oil rinse after the mineral spirits rinse, but the hardware store guys, as well as my own experience, make me loath to use any of that on plastic, especially PE. Heavy-duty PE? Not the low-end one I bought. Yet another product that should not have been sold, which is, of course, the entire point.
Most of the sprayers used for deck sealer are made from fairly heavy duty polyethylene, and so are the pumps. There may possibly be an issue with the "O" ring seals, but not rapid damage. Cleaning out the sealer should not take very long, and so any deterioration would be minimal. Leaving mineral spirits in for an extended period of time is an entirely different story. That would probably cause damage on most sprayers. You notice that I did say to use some sort of oil after rinsing it with the mineral spirits, which is because it is not a good idea to leave them in the sprayer. In fact, I neglected to mention that only a metal spray head could be stored on a container of mineral spirits. Sorry about that.
The "Binks" sprayer that I mentioned is indeed an all metal spray gun intended for auto,otive paints and lacquers. It is made of aluminum and brass, and the tank only holds about a pint of paint. It is totally different from the sprayers for spraying a deck. You would see sprayers like it in auto body repair shops.
William, thanks for the ideas on cleaning. I was told I couldn't use that approach, i.e., use mineral spirits for cleaning or storage, because it would damage the plastic. The $40 sprayers must be made of much more fragile plastic than your $110 version.
That was also my impression – the tube was chrome plated – EXTERNALLY ! What's the point of skipping the working side of the plating-? Making junk, selling junk. You would think they would be going out-of-business, and deservedly so. But the points raised of one-time use are probably the whopping majority of their sales figures, so they will never feel the pain of losing repeat sales. I think its Bad business, but unfortunately (probably) a very common scenario,,,,
Ann, actually it is quite possible to clean the plastic deck sealer sprayers, I have done it a few times. After the first coat is applied and all of the sealer used up, run some mineral spirits through the spray tube and spray head. Use the cheapest spirits that you can buy. And you can save them in a sealed jar for cleaning the second time. But running a cup or so through the spray head , wand, and control valve does a fairly good cleaning out. Then store the nozzel in a small jar submerged in mineral spirits. That keeps any residue from hardening. After the last use and cleaning you can run some cheap oil into the sprayer. Even used deep-fryer oil, if you filter out the crumbs. Then rinse it with detergent and water before using it the next time. The same approach also works for my $110 Binks sprayer.
The first Tacoma Narrows Bridge was a Washington State suspension bridge that opened in 1940 and spanned the Tacoma Narrows strait of Puget Sound between Tacoma and the Kitsap Peninsula. It opened to traffic on July 1, 1940, and dramatically collapsed into Puget Sound on November 7, just four months after it opened.
Noting that we now live in an era of “confusion and ill-conceived stuff,” Ammunition design studio founder Robert Brunner, speaking at Gigaom Roadmap, said that by adding connectivity to everything and its mother, we aren't necessarily doing ourselves any favors, with many ‘things’ just fine in their unconnected state.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.